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4.9 2.3.x imx #46

Merged
merged 1,123 commits into from
Mar 28, 2019
Merged

4.9 2.3.x imx #46

merged 1,123 commits into from
Mar 28, 2019

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GustavoARSilva and others added 30 commits March 13, 2019 14:04
commit d7ac3c6 upstream.

IndexCard is indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

drivers/char/applicom.c:418 ac_write() warn: potential spectre issue 'apbs' [r]
drivers/char/applicom.c:728 ac_ioctl() warn: potential spectre issue 'apbs' [r] (local cap)

Fix this by sanitizing IndexCard before using it to index apbs.

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://lore.kernel.org/lkml/[email protected]/

Cc: [email protected]
Signed-off-by: Gustavo A. R. Silva <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 72faa7a upstream.

The irq_pages is the number of pages for irq stack, but not the
order which is needed by __get_free_pages().
We can use get_order() to calculate the accurate order.

Signed-off-by: Liu Xiang <[email protected]>
Signed-off-by: Paul Burton <[email protected]>
Fixes: fe8bd18 ("MIPS: Introduce irq_stack")
Cc: [email protected]
Cc: [email protected] # v4.11+
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit cb6acd0 upstream.

hugetlb pages should only be migrated if they are 'active'.  The
routines set/clear_page_huge_active() modify the active state of hugetlb
pages.

When a new hugetlb page is allocated at fault time, set_page_huge_active
is called before the page is locked.  Therefore, another thread could
race and migrate the page while it is being added to page table by the
fault code.  This race is somewhat hard to trigger, but can be seen by
strategically adding udelay to simulate worst case scheduling behavior.
Depending on 'how' the code races, various BUG()s could be triggered.

To address this issue, simply delay the set_page_huge_active call until
after the page is successfully added to the page table.

Hugetlb pages can also be leaked at migration time if the pages are
associated with a file in an explicitly mounted hugetlbfs filesystem.
For example, consider a two node system with 4GB worth of huge pages
available.  A program mmaps a 2G file in a hugetlbfs filesystem.  It
then migrates the pages associated with the file from one node to
another.  When the program exits, huge page counts are as follows:

  node0
  1024    free_hugepages
  1024    nr_hugepages

  node1
  0       free_hugepages
  1024    nr_hugepages

  Filesystem                         Size  Used Avail Use% Mounted on
  nodev                              4.0G  2.0G  2.0G  50% /var/opt/hugepool

That is as expected.  2G of huge pages are taken from the free_hugepages
counts, and 2G is the size of the file in the explicitly mounted
filesystem.  If the file is then removed, the counts become:

  node0
  1024    free_hugepages
  1024    nr_hugepages

  node1
  1024    free_hugepages
  1024    nr_hugepages

  Filesystem                         Size  Used Avail Use% Mounted on
  nodev                              4.0G  2.0G  2.0G  50% /var/opt/hugepool

Note that the filesystem still shows 2G of pages used, while there
actually are no huge pages in use.  The only way to 'fix' the filesystem
accounting is to unmount the filesystem

If a hugetlb page is associated with an explicitly mounted filesystem,
this information in contained in the page_private field.  At migration
time, this information is not preserved.  To fix, simply transfer
page_private from old to new page at migration time if necessary.

There is a related race with removing a huge page from a file and
migration.  When a huge page is removed from the pagecache, the
page_mapping() field is cleared, yet page_private remains set until the
page is actually freed by free_huge_page().  A page could be migrated
while in this state.  However, since page_mapping() is not set the
hugetlbfs specific routine to transfer page_private is not called and we
leak the page count in the filesystem.

To fix that, check for this condition before migrating a huge page.  If
the condition is detected, return EBUSY for the page.

Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Fixes: bcc5422 ("mm: hugetlb: introduce page_huge_active")
Signed-off-by: Mike Kravetz <[email protected]>
Reviewed-by: Naoya Horiguchi <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: "Kirill A . Shutemov" <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: <[email protected]>
[[email protected]: v2]
  Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: update comment and changelog]
  Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit f612acf upstream.

syzkaller report this:
BUG: memory leak
unreferenced object 0xffffc9000488d000 (size 9195520):
  comm "syz-executor.0", pid 2752, jiffies 4294787496 (age 18.757s)
  hex dump (first 32 bytes):
    ff ff ff ff ff ff ff ff a8 00 00 00 01 00 00 00  ................
    02 00 00 00 00 00 00 00 80 a1 7a c1 ff ff ff ff  ..........z.....
  backtrace:
    [<000000000863775c>] __vmalloc_node mm/vmalloc.c:1795 [inline]
    [<000000000863775c>] __vmalloc_node_flags mm/vmalloc.c:1809 [inline]
    [<000000000863775c>] vmalloc+0x8c/0xb0 mm/vmalloc.c:1831
    [<000000003f668111>] kernel_read_file+0x58f/0x7d0 fs/exec.c:924
    [<000000002385813f>] kernel_read_file_from_fd+0x49/0x80 fs/exec.c:993
    [<0000000011953ff1>] __do_sys_finit_module+0x13b/0x2a0 kernel/module.c:3895
    [<000000006f58491f>] do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
    [<00000000ee78baf4>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<00000000241f889b>] 0xffffffffffffffff

It should goto 'out_free' lable to free allocated buf while kernel_read
fails.

Fixes: 39d637a ("vfs: forbid write access when reading a file into memory")
Signed-off-by: YueHaibing <[email protected]>
Signed-off-by: Al Viro <[email protected]>
Cc: Thibaut Sautereau <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 47bb117 upstream.

When initially testing the Camera Terminal Descriptor wTerminalType
field (buffer[4]), no mask is used. Later in the function, the MSB is
overloaded to store the descriptor subtype, and so a mask of 0x7fff
is used to check the type.

If a descriptor is specially crafted to set this overloaded bit in the
original wTerminalType field, the initial type check will fail (falling
through, without adjusting the buffer size), but the later type checks
will pass, assuming the buffer has been made suitably large, causing an
overflow.

Avoid this problem by checking for the MSB in the wTerminalType field.
If the bit is set, assume the descriptor is bad, and abort parsing it.

Originally reported here:
https://groups.google.com/forum/#!topic/syzkaller/Ot1fOE6v1d8
A similar (non-compiling) patch was provided at that time.

Reported-by: syzbot <[email protected]>
Signed-off-by: Alistair Strachan <[email protected]>
Signed-off-by: Laurent Pinchart <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
[ Upstream commit dd9ee34 ]

Recently we run a network test over ipcomp virtual tunnel.We find that
if a ipv4 packet needs fragment, then the peer can't receive
it.

We deep into the code and find that when packet need fragment the smaller
fragment will be encapsulated by ipip not ipcomp. So when the ipip packet
goes into xfrm, it's skb->dev is not properly set. The ipv4 reassembly code
always set skb'dev to the last fragment's dev. After ipv4 defrag processing,
when the kernel rp_filter parameter is set, the skb will be drop by -EXDEV
error.

This patch adds compatible support for the ipip process in ipcomp virtual tunnel.

Signed-off-by: Su Yanjun <[email protected]>
Signed-off-by: Steffen Klassert <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 1a51c5d ]

The perf_proc_update_handler() handles /proc/sys/kernel/perf_event_max_sample_rate
syctl variable.  When the PMU IRQ handler timing monitoring is disabled, i.e,
when /proc/sys/kernel/perf_cpu_time_max_percent is equal to 0 or 100,
then no modification to sysctl_perf_event_sample_rate is allowed to prevent
possible hang from wrong values.

The problem is that the test to prevent modification is made after the
sysctl variable is modified in perf_proc_update_handler().

You get an error:

  $ echo 10001 >/proc/sys/kernel/perf_event_max_sample_rate
  echo: write error: invalid argument

But the value is still modified causing all sorts of inconsistencies:

  $ cat /proc/sys/kernel/perf_event_max_sample_rate
  10001

This patch fixes the problem by moving the parsing of the value after
the test.

Committer testing:

  # echo 100 > /proc/sys/kernel/perf_cpu_time_max_percent
  # echo 10001 > /proc/sys/kernel/perf_event_max_sample_rate
  -bash: echo: write error: Invalid argument
  # cat /proc/sys/kernel/perf_event_max_sample_rate
  10001
  #

Signed-off-by: Stephane Eranian <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Reviewed-by: Jiri Olsa <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 1497e80 ]

This patch fixes an issue in cpumap.c when used with the TOPOLOGY
header. In some configurations, some NUMA nodes may have no CPU (empty
cpulist). Yet a cpumap map must be created otherwise perf abort with an
error. This patch handles this case by creating a dummy map.

  Before:

  $ perf record -o - -e cycles noploop 2 | perf script -i -
  0x6e8 [0x6c]: failed to process type: 80

  After:

  $ perf record -o - -e cycles noploop 2 | perf script -i -
  noploop for 2 seconds

Signed-off-by: Stephane Eranian <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 904bba2 ]

The work completion length for a receiving a UD send with immediate is
short by 4 bytes causing application using this opcode to fail.

The UD receive logic incorrectly subtracts 4 bytes for immediate
value. These bytes are already included in header length and are used to
calculate header/payload split, so the result is these 4 bytes are
subtracted twice, once when the header length subtracted from the overall
length and once again in the UD opcode specific path.

Remove the extra subtraction when handling the opcode.

Fixes: 7724105 ("IB/hfi1: add driver files")
Reviewed-by: Michael J. Ruhl <[email protected]>
Signed-off-by: Brian Welty <[email protected]>
Signed-off-by: Mike Marciniszyn <[email protected]>
Signed-off-by: Dennis Dalessandro <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 51d8838 ]

In the error path of map_sg, free_iova_fast is being called with
address instead of the pfn. This results in a bad value getting into
the rcache, and can result in hitting a BUG_ON when
iova_magazine_free_pfns is called.

Cc: Joerg Roedel <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Signed-off-by: Jerry Snitselaar <[email protected]>
Fixes: 80187fd ("iommu/amd: Optimize map_sg and unmap_sg")
Signed-off-by: Joerg Roedel <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit f1724c0 ]

In the error path of map_sg there is an incorrect if condition
for breaking out of the loop that searches the scatterlist
for mapped pages to unmap. Instead of breaking out of the
loop once all the pages that were mapped have been unmapped,
it will break out of the loop after it has unmapped 1 page.
Fix the condition, so it breaks out of the loop only after
all the mapped pages have been unmapped.

Fixes: 80187fd ("iommu/amd: Optimize map_sg and unmap_sg")
Cc: Joerg Roedel <[email protected]>
Signed-off-by: Jerry Snitselaar <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 53ab60b ]

There is a UBSAN bug report as below:
UBSAN: Undefined behaviour in net/netfilter/ipvs/ip_vs_ctl.c:2227:21
signed integer overflow:
-2147483647 * 1000 cannot be represented in type 'int'

Reproduce program:
	#include <stdio.h>
	#include <sys/types.h>
	#include <sys/socket.h>

	#define IPPROTO_IP 0
	#define IPPROTO_RAW 255

	#define IP_VS_BASE_CTL		(64+1024+64)
	#define IP_VS_SO_SET_TIMEOUT	(IP_VS_BASE_CTL+10)

	/* The argument to IP_VS_SO_GET_TIMEOUT */
	struct ipvs_timeout_t {
		int tcp_timeout;
		int tcp_fin_timeout;
		int udp_timeout;
	};

	int main() {
		int ret = -1;
		int sockfd = -1;
		struct ipvs_timeout_t to;

		sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
		if (sockfd == -1) {
			printf("socket init error\n");
			return -1;
		}

		to.tcp_timeout = -2147483647;
		to.tcp_fin_timeout = -2147483647;
		to.udp_timeout = -2147483647;

		ret = setsockopt(sockfd,
				 IPPROTO_IP,
				 IP_VS_SO_SET_TIMEOUT,
				 (char *)(&to),
				 sizeof(to));

		printf("setsockopt return %d\n", ret);
		return ret;
	}

Return -EINVAL if the timeout value is negative or max than 'INT_MAX / HZ'.

Signed-off-by: ZhangXiaoxu <[email protected]>
Acked-by: Simon Horman <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 9825bd9 ]

When a VM is terminated, the VFIO driver detaches all pass-through
devices from VFIO domain by clearing domain id and page table root
pointer from each device table entry (DTE), and then invalidates
the DTE. Then, the VFIO driver unmap pages and invalidate IOMMU pages.

Currently, the IOMMU driver keeps track of which IOMMU and how many
devices are attached to the domain. When invalidate IOMMU pages,
the driver checks if the IOMMU is still attached to the domain before
issuing the invalidate page command.

However, since VFIO has already detached all devices from the domain,
the subsequent INVALIDATE_IOMMU_PAGES commands are being skipped as
there is no IOMMU attached to the domain. This results in data
corruption and could cause the PCI device to end up in indeterministic
state.

Fix this by invalidate IOMMU pages when detach a device, and
before decrementing the per-domain device reference counts.

Cc: Boris Ostrovsky <[email protected]>
Suggested-by: Joerg Roedel <[email protected]>
Co-developed-by: Brijesh Singh <[email protected]>
Signed-off-by: Brijesh Singh <[email protected]>
Signed-off-by: Suravee Suthikulpanit <[email protected]>
Fixes: 6de8ad9 ('x86/amd-iommu: Make iommu_flush_pages aware of multiple IOMMUs')
Signed-off-by: Joerg Roedel <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 4fe8713 ]

ccount_timer_shutdown is called from the atomic context in the
secondary_start_kernel, resulting in the following BUG:

BUG: sleeping function called from invalid context
in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/1
Preemption disabled at:
  secondary_start_kernel+0xa1/0x130
Call Trace:
  ___might_sleep+0xe7/0xfc
  __might_sleep+0x41/0x44
  synchronize_irq+0x24/0x64
  disable_irq+0x11/0x14
  ccount_timer_shutdown+0x12/0x20
  clockevents_switch_state+0x82/0xb4
  clockevents_exchange_device+0x54/0x60
  tick_check_new_device+0x46/0x70
  clockevents_register_device+0x8c/0xc8
  clockevents_config_and_register+0x1d/0x2c
  local_timer_setup+0x75/0x7c
  secondary_start_kernel+0xb4/0x130
  should_never_return+0x32/0x35

Use disable_irq_nosync instead of disable_irq to avoid it.
This is safe because the ccount timer IRQ is per-CPU, and once IRQ is
masked the ISR will not be called.

Signed-off-by: Max Filippov <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 32a7726 ]

- add missing memory barriers to the secondary CPU synchronization spin
  loops; add comment to the matching memory barrier in the boot_secondary
  and __cpu_die functions;
- use READ_ONCE/WRITE_ONCE to access cpu_start_id/cpu_start_ccount
  instead of reading/writing them directly;
- re-initialize cpu_running every time before starting secondary CPU to
  flush possible previous CPU startup results.

Signed-off-by: Max Filippov <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 306b383 ]

Secondary CPU reset vector overlaps part of the double exception handler
code, resulting in weird crashes and hangups when running user code.
Move exception vectors one page up so that they don't clash with the
secondary CPU reset vector.

Signed-off-by: Max Filippov <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 8b1c42c ]

Otherwise it is impossible to enable CPUs after booting with 'maxcpus'
parameter.

Signed-off-by: Max Filippov <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 25384ce ]

This fixes the following warning at boot when the kernel is booted on a
board with more CPU cores than was configured in NR_CPUS:

  smp_init_cpus: Core Count = 8
  smp_init_cpus: Core Id = 0
  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 0 at include/linux/cpumask.h:121 smp_init_cpus+0x54/0x74
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 5.0.0-rc3-00015-g1459333f88a0 Freescale#124
  Call Trace:
    __warn$part$3+0x6a/0x7c
    warn_slowpath_null+0x35/0x3c
    smp_init_cpus+0x54/0x74
    setup_arch+0x1c0/0x1d0
    start_kernel+0x44/0x310
    _startup+0x107/0x107

Signed-off-by: Max Filippov <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 6571ebc ]

If fill_level was not zero and status was not BUSY,
result of "tx_prod - tx_cons - inuse" might be zero.
Subtracting 1 unconditionally results invalid negative return value
on this case.
Make sure not to return an negative value.

Signed-off-by: Tomonori Sakita <[email protected]>
Signed-off-by: Atsushi Nemoto <[email protected]>
Reviewed-by: Dalon L Westergreen <[email protected]>
Acked-by: Thor Thayer <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 263c6d7 ]

In hns enet driver, we use of_parse_handle() to get hold of the
device node related to "ae-handle" but we have missed to put
the node reference using of_node_put() after we are done using
the node. This patch fixes it.

Note:
This problem is stated in Link: https://lkml.org/lkml/2018/12/22/217

Fixes: 48189d6 ("net: hns: enet specifies a reference to dsaf")
Reported-by: Alexey Khoroshilov <[email protected]>
Signed-off-by: Yonglong Liu <[email protected]>
Signed-off-by: Peng Li <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit cec8abb ]

When reading phy registers via Clause 45 MDIO protocol, after write
address operation, the driver use another write address operation, so
can not read the right value of any phy registers. This patch fixes it.

Signed-off-by: Yonglong Liu <[email protected]>
Signed-off-by: Peng Li <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit c69c29a ]

If phy_power_on() fails in rk_gmac_powerup(), clocks are left enabled.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 7ae710f ]

On SoC reset all GPIO interrupts are disable. However, if kexec is
used to boot into a new kernel, the SoC does not experience a
reset. Hence GPIO interrupts can be left enabled from the previous
kernel. It is then possible for the interrupt to fire before an
interrupt handler is registered, resulting in the kernel complaining
of an "unexpected IRQ trap", the interrupt is never cleared, and so
fires again, resulting in an interrupt storm.

Disable all GPIO interrupts before registering the GPIO IRQ chip.

Fixes: 7f2691a ("gpio: vf610: add gpiolib/IRQ chip driver for Vybrid")
Signed-off-by: Andrew Lunn <[email protected]>
Acked-by: Stefan Agner <[email protected]>
Signed-off-by: Linus Walleij <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 80ff001 ]

There is a NULL pointer dereference of dev_name in nfs_parse_devname()

The oops looks something like:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
  ...
  RIP: 0010:nfs_fs_mount+0x3b6/0xc20 [nfs]
  ...
  Call Trace:
   ? ida_alloc_range+0x34b/0x3d0
   ? nfs_clone_super+0x80/0x80 [nfs]
   ? nfs_free_parsed_mount_data+0x60/0x60 [nfs]
   mount_fs+0x52/0x170
   ? __init_waitqueue_head+0x3b/0x50
   vfs_kern_mount+0x6b/0x170
   do_mount+0x216/0xdc0
   ksys_mount+0x83/0xd0
   __x64_sys_mount+0x25/0x30
   do_syscall_64+0x65/0x220
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fix this by adding a NULL check on dev_name

Signed-off-by: Yao Liu <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 327852e ]

VFs may hit VF-PF channel timeout while probing, as in some
cases it was observed that VF FLR and VF "acquire" message
transaction (i.e first message from VF to PF in VF's probe flow)
could occur simultaneously which could lead VF to fail sending
"acquire" message to PF as VF is marked disabled from HW perspective
due to FLR, which will result into channel timeout and VF probe failure.

In such cases, try retrying VF "acquire" message so that in later
attempts it could be successful to pass message to PF after the VF
FLR is completed and can be probed successfully.

Signed-off-by: Manish Chopra <[email protected]>
Signed-off-by: Ariel Elior <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 5d8fc4a ]

The issue to be fixed in this commit is when libfc found it received a
invalid FLOGI response from FC switch, it would return without freeing the
fc frame, which is just the skb data. This would cause memory leak if FC
switch keeps sending invalid FLOGI responses.

This fix is just to make it execute `fc_frame_free(fp)` before returning
from function `fc_lport_flogi_resp`.

Signed-off-by: Ming Lu <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 0ee4b5f ]

Add BACKLIGHT_LCD_SUPPORT for SAMSUNG_Q10 to fix the
warning: unmet direct dependencies detected for BACKLIGHT_CLASS_DEVICE.

SAMSUNG_Q10 selects BACKLIGHT_CLASS_DEVICE but BACKLIGHT_CLASS_DEVICE
depends on BACKLIGHT_LCD_SUPPORT.

Copy BACKLIGHT_LCD_SUPPORT dependency into SAMSUNG_Q10 to fix:

WARNING: unmet direct dependencies detected for BACKLIGHT_CLASS_DEVICE
  Depends on [n]: HAS_IOMEM [=y] && BACKLIGHT_LCD_SUPPORT [=n]
  Selected by [y]:
  - SAMSUNG_Q10 [=y] && X86 [=y] && X86_PLATFORM_DEVICES [=y] && ACPI [=y]

Signed-off-by: Sinan Kaya <[email protected]>
Acked-by: Andy Shevchenko <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 58d15ed ]

The size of the fixed part of the create response is 88 bytes not 56.

Signed-off-by: Ronnie Sahlberg <[email protected]>
Signed-off-by: Steve French <[email protected]>
Reviewed-by: Pavel Shilovsky <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit f2b3d85 ]

On systems with VHE the kernel and KVM's world-switch code run at the
same exception level. Code that is only used on a VHE system does not
need to be annotated as __hyp_text as it can reside anywhere in the
 kernel text.

__hyp_text was also used to prevent kprobes from patching breakpoint
instructions into this region, as this code runs at a different
exception level. While this is no longer true with VHE, KVM still
switches VBAR_EL1, meaning a kprobe's breakpoint executed in the
world-switch code will cause a hyp-panic.

Move the __hyp_text check in the kprobes blacklist so it applies on
VHE systems too, to cover the common code and guest enter/exit
assembly.

Fixes: 888b3c8 ("arm64: Treat all entry code as non-kprobe-able")
Reviewed-by: Christoffer Dall <[email protected]>
Signed-off-by: James Morse <[email protected]>
Acked-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
[ Upstream commit 2aa958c ]

Kexec-ing a kernel with "efi=noruntime" on the first kernel's command
line causes the following null pointer dereference:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
  #PF error: [normal kernel read fault]
  Call Trace:
   efi_runtime_map_copy+0x28/0x30
   bzImage64_load+0x688/0x872
   arch_kexec_kernel_image_load+0x6d/0x70
   kimage_file_alloc_init+0x13e/0x220
   __x64_sys_kexec_file_load+0x144/0x290
   do_syscall_64+0x55/0x1a0
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

Just skip the EFI info setup if EFI runtime services are not enabled.

 [ bp: Massage commit message. ]

Suggested-by: Dave Young <[email protected]>
Signed-off-by: Kairui Song <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Acked-by: Dave Young <[email protected]>
Cc: AKASHI Takahiro <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: [email protected]
Cc: David Howells <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: Philipp Rudo <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Thomas Gleixner <[email protected]>
Cc: x86-ml <[email protected]>
Cc: Yannik Sembritzki <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
Al Viro and others added 12 commits March 27, 2019 14:13
commit 81be24d upstream.

It's not hard to trigger a bunch of d_invalidate() on the same
dentry in parallel.  They end up fighting each other - any
dentry picked for removal by one will be skipped by the rest
and we'll go for the next iteration through the entire
subtree, even if everything is being skipped.  Morevoer, we
immediately go back to scanning the subtree.  The only thing
we really need is to dissolve all mounts in the subtree and
as soon as we've nothing left to do, we can just unhash the
dentry and bugger off.

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 6f44a0b upstream.

In current die(), the irq is disabled for __die() handle, not
including the possible panic() handling. Since the log in __die()
can take several hundreds ms, new irq might come and interrupt
current die().

If the process calling die() holds some critical resource, and some
other process scheduled later also needs it, then it would deadlock.
The first panic will not be executed.

So here disable irq for the whole flow of die().

Signed-off-by: Qiao Zhou <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 4350782 upstream.

On Spreadtrum's serial device, nearly all of interrupts would be cleared
by hardware except timeout interrupt.  This patch removed the operation
of clearing all interrupt in irq handler, instead added an if statement
to check if the timeout interrupt is supposed to be cleared.

Wrongly clearing timeout interrupt would lead to uart data stay in rx
fifo, that means the driver cannot read them out anymore.

Signed-off-by: Lanqing Liu <[email protected]>
Signed-off-by: Chunyan Zhang <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 3f32957 upstream.

The current int_sqrt() computation is sub-optimal for the case of small
@x.  Which is the interesting case when we're going to do cumulative
distribution functions on idle times, which we assume to be a random
variable, where the target residency of the deepest idle state gives an
upper bound on the variable (5e6ns on recent Intel chips).

In the case of small @x, the compute loop:

	while (m != 0) {
		b = y + m;
		y >>= 1;

		if (x >= b) {
			x -= b;
			y += m;
		}
		m >>= 2;
	}

can be reduced to:

	while (m > x)
		m >>= 2;

Because y==0, b==m and until x>=m y will remain 0.

And while this is computationally equivalent, it runs much faster
because there's less code, in particular less branches.

      cycles:                 branches:              branch-misses:

OLD:

hot:   45.109444 +- 0.044117  44.333392 +- 0.002254  0.018723 +- 0.000593
cold: 187.737379 +- 0.156678  44.333407 +- 0.002254  6.272844 +- 0.004305

PRE:

hot:   67.937492 +- 0.064124  66.999535 +- 0.000488  0.066720 +- 0.001113
cold: 232.004379 +- 0.332811  66.999527 +- 0.000488  6.914634 +- 0.006568

POST:

hot:   43.633557 +- 0.034373  45.333132 +- 0.002277  0.023529 +- 0.000681
cold: 207.438411 +- 0.125840  45.333132 +- 0.002277  6.976486 +- 0.004219

Averages computed over all values <128k using a LFSR to generate order.
Cold numbers have a LFSR based branch trace buffer 'confuser' ran between
each int_sqrt() invocation.

Link: http://lkml.kernel.org/r/[email protected]
Fixes: 30493cc ("lib/int_sqrt.c: optimize square root algorithm")
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Suggested-by: Anshul Garg <[email protected]>
Acked-by: Linus Torvalds <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: David Miller <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Michael Davidson <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 32fd87b upstream.

When cleaning up the configurations, make sure we only free the number
of configurations and interfaces that we could have allocated.

Reported-by: Andrey Konovalov <[email protected]>
Cc: stable <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 83dc7e3 upstream.

Since the command type of UTRD in UFS 2.1 specification is the same with
UFS 2.0. And it assumes the future UFS specification will follow the
same definition.

Signed-off-by: kehuanlin <[email protected]>
Reviewed-by: Subhash Jadavani <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 36d46cd upstream.

If we convert one large time values to rtc_time, in the original formula
'days * 86400' can be overflowed in 'unsigned int' type to make the formula
get one incorrect remain seconds value. Thus we can use div_s64_rem()
function to avoid this situation.

Signed-off-by: Baolin Wang <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Signed-off-by: Alexandre Belloni <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 5fb5cae upstream.

Before this patch the enable signal was set before the PWM signal and
vice-versa on power off. This sequence is wrong, at least, it is on
the different panels datasheets that I checked, so I inverted the sequence
to follow the specs.

For reference the following panels have the mentioned sequence:
  - N133HSE-EA1 (Innolux)
  - N116BGE (Innolux)
  - N156BGE-L21 (Innolux)
  - B101EAN0 (Auo)
  - B101AW03 (Auo)
  - LTN101NT05 (Samsung)
  - CLAA101WA01A (Chunghwa)

Signed-off-by: Enric Balletbo i Serra <[email protected]>
Acked-by: Daniel Thompson <[email protected]>
Acked-by: Jingoo Han <[email protected]>
Acked-by: Thierry Reding <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit f25a646 upstream.

Fix incorrect return value.

Signed-off-by: Baolin Wang <[email protected]>
Signed-off-by: Sebastian Reichel <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
commit 6707ba0 upstream.

The way that 'strncat' is used here raised a warning in gcc-8:

drivers/net/wireless/ath/ath10k/wmi.c: In function 'ath10k_wmi_tpc_stats_final_disp_tables':
drivers/net/wireless/ath/ath10k/wmi.c:4649:4: error: 'strncat' output truncated before terminating nul copying as many bytes from a string as its length [-Werror=stringop-truncation]

Effectively, this is simply a strcat() but the use of strncat() suggests
some form of overflow check. Regardless of whether this might actually
overflow, using strlcat() instead of strncat() avoids the warning and
makes the code more robust.

Fixes: bc64d05 ("ath10k: debugfs support to get final TPC stats for 10.4 variants")
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This is the 4.9.166 stable release
ziswiler pushed a commit to toradex/linux-fslc that referenced this pull request Mar 28, 2019
commit 90cc55f upstream.

Otherwise we introduce a race condition where userspace can request input
before we're ready leading to null pointer dereference such as

input: bma150 as /devices/platform/i2c-gpio-2/i2c-5/5-0038/input/input3
Unable to handle kernel NULL pointer dereference at virtual address 00000018
pgd = (ptrval)
[00000018] *pgd=55dac831, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [Freescale#1] PREEMPT ARM
Modules linked in: bma150 input_polldev [last unloaded: bma150]
CPU: 0 PID: 2870 Comm: accelerometer Not tainted 5.0.0-rc3-dirty Freescale#46
Hardware name: Samsung S5PC110/S5PV210-based board
PC is at input_event+0x8/0x60
LR is at bma150_report_xyz+0x9c/0xe0 [bma150]
pc : [<80450f70>]    lr : [<7f0a614c>]    psr: 800d0013
sp : a4c1fd78  ip : 00000081  fp : 00020000
r10: 00000000  r9 : a5e2944c  r8 : a7455000
r7 : 00000016  r6 : 00000101  r5 : a7617940  r4 : 80909048
r3 : fffffff2  r2 : 00000000  r1 : 00000003  r0 : 00000000
Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 10c5387d  Table: 54e34019  DAC: 00000051
Process accelerometer (pid: 2870, stack limit = 0x(ptrval))
Stackck: (0xa4c1fd78 to 0xa4c20000)
fd60:                                                       fffffff3 fc813f6c
fd80: 40410581 d7530ce3 a5e2817c a7617f00 a5e29404 a5e2817c 00000000 7f008324
fda0: a5e28000 8044f59c a5fdd9d0 a5e2945c a46a4a00 a5e29668 a7455000 80454f10
fdc0: 80909048 a5e29668 a5fdd9d0 a46a4a00 806316d0 00000000 a46a4a00 801df5f0
fde0: 00000000 d7530ce3 a4c1fec0 a46a4a00 00000000 a5fdd9d0 a46a4a08 801df53c
fe00: 00000000 801d74bc a4c1fec0 00000000 a4c1ff70 00000000 a7038da8 00000000
fe20: a46a4a00 801e91fc a411bbe0 801f2e88 00000004 00000000 80909048 00000041
fe40: 00000000 00020000 00000000 dead4ead a6a88da0 00000000 ffffe000 806fcae8
fe60: a4c1fec8 00000000 80909048 00000002 a5fdd9d0 a7660110 a411bab0 00000001
fe80: dead4ead ffffffff ffffffff a4c1fe8c a4c1fe8c d7530ce3 20000013 80909048
fea0: 80909048 a4c1ff70 00000001 fffff000 a4c1e000 00000005 00026038 801eabd8
fec0: a7660110 a411bab0 b9394901 00000006 a696201b 76fb3000 00000000 a7039720
fee0: a5fdd9d0 00000101 00000002 00000096 00000000 00000000 00000000 a4c1ff00
ff00: a6b310f4 805cb174 a6b310f4 00000010 00000fe0 00000010 a4c1e000 d7530ce3
ff20: 00000003 a5f41400 a5f41424 00000000 a6962000 00000000 00000003 00000002
ff40: ffffff9c 000a0000 80909048 d7530ce3 a6962000 00000003 80909048 ffffff9c
ff60: a6962000 801d890c 00000000 00000000 00020000 a7590000 00000004 00000100
ff80: 00000001 d7530ce3 000288b8 00026320 000288b8 00000005 80101204 a4c1e000
ffa0: 00000005 80101000 000288b8 00026320 000288b8 000a0000 00000000 00000000
ffc0: 000288b8 00026320 000288b8 00000005 7eef3bac 000264e8 00028ad8 00026038
ffe0: 00000005 7eef3300 76f76e91 76f78546 800d0030 000288b8 00000000 00000000
[<80450f70>] (input_event) from [<a5e2817c>] (0xa5e2817c)
Code: e1a08148 eaffffa8 e351001f 812fff1e (e590c018)
---[ end trace 1c691ee85f2ff243 ]---

Signed-off-by: Jonathan Bakker <[email protected]>
Signed-off-by: Paweł Chmiel <[email protected]>
Cc: [email protected]
Signed-off-by: Dmitry Torokhov <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
@otavio otavio merged commit 0a8ab17 into Freescale:4.9-2.3.x-imx Mar 28, 2019
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Nov 24, 2020
[ Upstream commit 3d51794 ]

When removing the driver we would hit BUG_ON(!list_empty(&dev->ptype_specific))
in net/core/dev.c due to still having the NC-SI packet handler
registered.

 # echo 1e660000.ethernet > /sys/bus/platform/drivers/ftgmac100/unbind
  ------------[ cut here ]------------
  kernel BUG at net/core/dev.c:10254!
  Internal error: Oops - BUG: 0 [Freescale#1] SMP ARM
  CPU: 0 PID: 115 Comm: sh Not tainted 5.10.0-rc3-next-20201111-00007-g02e0365710c4 Freescale#46
  Hardware name: Generic DT based system
  PC is at netdev_run_todo+0x314/0x394
  LR is at cpumask_next+0x20/0x24
  pc : [<806f5830>]    lr : [<80863cb0>]    psr: 80000153
  sp : 855bbd58  ip : 00000001  fp : 855bbdac
  r10: 80c03d00  r9 : 80c06228  r8 : 81158c54
  r7 : 00000000  r6 : 80c05dec  r5 : 80c05d18  r4 : 813b9280
  r3 : 813b9054  r2 : 8122c470  r1 : 00000002  r0 : 00000002
  Flags: Nzcv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment none
  Control: 00c5387d  Table: 85514008  DAC: 00000051
  Process sh (pid: 115, stack limit = 0x7cb5703d)
 ...
  Backtrace:
  [<806f551c>] (netdev_run_todo) from [<80707eec>] (rtnl_unlock+0x18/0x1c)
   r10:00000051 r9:854ed710 r8:81158c54 r7:80c76bb0 r6:81158c10 r5:8115b410
   r4:813b9000
  [<80707ed4>] (rtnl_unlock) from [<806f5db8>] (unregister_netdev+0x2c/0x30)
  [<806f5d8c>] (unregister_netdev) from [<805a8180>] (ftgmac100_remove+0x20/0xa8)
   r5:8115b410 r4:813b9000
  [<805a8160>] (ftgmac100_remove) from [<805355e4>] (platform_drv_remove+0x34/0x4c)

Fixes: bd466c3 ("net/faraday: Support NCSI mode")
Signed-off-by: Joel Stanley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
LeBlue pushed a commit to LeBlue/linux-fslc that referenced this pull request May 1, 2021
[ Upstream commit 3d51794 ]

When removing the driver we would hit BUG_ON(!list_empty(&dev->ptype_specific))
in net/core/dev.c due to still having the NC-SI packet handler
registered.

 # echo 1e660000.ethernet > /sys/bus/platform/drivers/ftgmac100/unbind
  ------------[ cut here ]------------
  kernel BUG at net/core/dev.c:10254!
  Internal error: Oops - BUG: 0 [Freescale#1] SMP ARM
  CPU: 0 PID: 115 Comm: sh Not tainted 5.10.0-rc3-next-20201111-00007-g02e0365710c4 Freescale#46
  Hardware name: Generic DT based system
  PC is at netdev_run_todo+0x314/0x394
  LR is at cpumask_next+0x20/0x24
  pc : [<806f5830>]    lr : [<80863cb0>]    psr: 80000153
  sp : 855bbd58  ip : 00000001  fp : 855bbdac
  r10: 80c03d00  r9 : 80c06228  r8 : 81158c54
  r7 : 00000000  r6 : 80c05dec  r5 : 80c05d18  r4 : 813b9280
  r3 : 813b9054  r2 : 8122c470  r1 : 00000002  r0 : 00000002
  Flags: Nzcv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment none
  Control: 00c5387d  Table: 85514008  DAC: 00000051
  Process sh (pid: 115, stack limit = 0x7cb5703d)
 ...
  Backtrace:
  [<806f551c>] (netdev_run_todo) from [<80707eec>] (rtnl_unlock+0x18/0x1c)
   r10:00000051 r9:854ed710 r8:81158c54 r7:80c76bb0 r6:81158c10 r5:8115b410
   r4:813b9000
  [<80707ed4>] (rtnl_unlock) from [<806f5db8>] (unregister_netdev+0x2c/0x30)
  [<806f5d8c>] (unregister_netdev) from [<805a8180>] (ftgmac100_remove+0x20/0xa8)
   r5:8115b410 r4:813b9000
  [<805a8160>] (ftgmac100_remove) from [<805355e4>] (platform_drv_remove+0x34/0x4c)

Fixes: bd466c3 ("net/faraday: Support NCSI mode")
Signed-off-by: Joel Stanley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request May 14, 2021
[ Upstream commit 0f20615 ]

Fix BPF_CORE_READ_BITFIELD() macro used for reading CO-RE-relocatable
bitfields. Missing breaks in a switch caused 8-byte reads always. This can
confuse libbpf because it does strict checks that memory load size corresponds
to the original size of the field, which in this case quite often would be
wrong.

After fixing that, we run into another problem, which quite subtle, so worth
documenting here. The issue is in Clang optimization and CO-RE relocation
interactions. Without that asm volatile construct (also known as
barrier_var()), Clang will re-order BYTE_OFFSET and BYTE_SIZE relocations and
will apply BYTE_OFFSET 4 times for each switch case arm. This will result in
the same error from libbpf about mismatch of memory load size and original
field size. I.e., if we were reading u32, we'd still have *(u8 *), *(u16 *),
*(u32 *), and *(u64 *) memory loads, three of which will fail. Using
barrier_var() forces Clang to apply BYTE_OFFSET relocation first (and once) to
calculate p, after which value of p is used without relocation in each of
switch case arms, doing appropiately-sized memory load.

Here's the list of relevant relocations and pieces of generated BPF code
before and after this patch for test_core_reloc_bitfields_direct selftests.

BEFORE
=====
 Freescale#45: core_reloc: insn Freescale#160 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32
 Freescale#46: core_reloc: insn Freescale#167 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#47: core_reloc: insn Freescale#174 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#48: core_reloc: insn Freescale#178 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#49: core_reloc: insn Freescale#182 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32

     157:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     159:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     160:       b7 02 00 00 04 00 00 00 r2 = 4
; BYTE_SIZE relocation here                 ^^^
     161:       66 02 07 00 03 00 00 00 if w2 s> 3 goto +7 <LBB0_63>
     162:       16 02 0d 00 01 00 00 00 if w2 == 1 goto +13 <LBB0_65>
     163:       16 02 01 00 02 00 00 00 if w2 == 2 goto +1 <LBB0_66>
     164:       05 00 12 00 00 00 00 00 goto +18 <LBB0_69>

0000000000000528 <LBB0_66>:
     165:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     167:       69 11 08 00 00 00 00 00 r1 = *(u16 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     168:       05 00 0e 00 00 00 00 00 goto +14 <LBB0_69>

0000000000000548 <LBB0_63>:
     169:       16 02 0a 00 04 00 00 00 if w2 == 4 goto +10 <LBB0_67>
     170:       16 02 01 00 08 00 00 00 if w2 == 8 goto +1 <LBB0_68>
     171:       05 00 0b 00 00 00 00 00 goto +11 <LBB0_69>

0000000000000560 <LBB0_68>:
     172:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     174:       79 11 08 00 00 00 00 00 r1 = *(u64 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     175:       05 00 07 00 00 00 00 00 goto +7 <LBB0_69>

0000000000000580 <LBB0_65>:
     176:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     178:       71 11 08 00 00 00 00 00 r1 = *(u8 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     179:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

00000000000005a0 <LBB0_67>:
     180:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     182:       61 11 08 00 00 00 00 00 r1 = *(u32 *)(r1 + 8)
; BYTE_OFFSET relo here w/ RIGHT size        ^^^^^^^^^^^^^^^^

00000000000005b8 <LBB0_69>:
     183:       67 01 00 00 20 00 00 00 r1 <<= 32
     184:       b7 02 00 00 00 00 00 00 r2 = 0
     185:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     186:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     187:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000005e0 <LBB0_71>:
     188:       77 01 00 00 20 00 00 00 r1 >>= 32

AFTER
=====

 Freescale#30: core_reloc: insn Freescale#132 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#31: core_reloc: insn Freescale#134 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32

     129:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     131:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     132:       b7 01 00 00 08 00 00 00 r1 = 8
; BYTE_OFFSET relo here                     ^^^
; no size check for non-memory dereferencing instructions
     133:       0f 12 00 00 00 00 00 00 r2 += r1
     134:       b7 03 00 00 04 00 00 00 r3 = 4
; BYTE_SIZE relocation here                 ^^^
     135:       66 03 05 00 03 00 00 00 if w3 s> 3 goto +5 <LBB0_63>
     136:       16 03 09 00 01 00 00 00 if w3 == 1 goto +9 <LBB0_65>
     137:       16 03 01 00 02 00 00 00 if w3 == 2 goto +1 <LBB0_66>
     138:       05 00 0a 00 00 00 00 00 goto +10 <LBB0_69>

0000000000000458 <LBB0_66>:
     139:       69 21 00 00 00 00 00 00 r1 = *(u16 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     140:       05 00 08 00 00 00 00 00 goto +8 <LBB0_69>

0000000000000468 <LBB0_63>:
     141:       16 03 06 00 04 00 00 00 if w3 == 4 goto +6 <LBB0_67>
     142:       16 03 01 00 08 00 00 00 if w3 == 8 goto +1 <LBB0_68>
     143:       05 00 05 00 00 00 00 00 goto +5 <LBB0_69>

0000000000000480 <LBB0_68>:
     144:       79 21 00 00 00 00 00 00 r1 = *(u64 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     145:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

0000000000000490 <LBB0_65>:
     146:       71 21 00 00 00 00 00 00 r1 = *(u8 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     147:       05 00 01 00 00 00 00 00 goto +1 <LBB0_69>

00000000000004a0 <LBB0_67>:
     148:       61 21 00 00 00 00 00 00 r1 = *(u32 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^

00000000000004a8 <LBB0_69>:
     149:       67 01 00 00 20 00 00 00 r1 <<= 32
     150:       b7 02 00 00 00 00 00 00 r2 = 0
     151:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     152:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     153:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000004d0 <LBB0_71>:
     154:       77 01 00 00 20 00 00 00 r1 >>= 323

Fixes: ee26dad ("libbpf: Add support for relocatable bitfields")
Signed-off-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Lorenz Bauer <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request May 14, 2021
[ Upstream commit 0f20615 ]

Fix BPF_CORE_READ_BITFIELD() macro used for reading CO-RE-relocatable
bitfields. Missing breaks in a switch caused 8-byte reads always. This can
confuse libbpf because it does strict checks that memory load size corresponds
to the original size of the field, which in this case quite often would be
wrong.

After fixing that, we run into another problem, which quite subtle, so worth
documenting here. The issue is in Clang optimization and CO-RE relocation
interactions. Without that asm volatile construct (also known as
barrier_var()), Clang will re-order BYTE_OFFSET and BYTE_SIZE relocations and
will apply BYTE_OFFSET 4 times for each switch case arm. This will result in
the same error from libbpf about mismatch of memory load size and original
field size. I.e., if we were reading u32, we'd still have *(u8 *), *(u16 *),
*(u32 *), and *(u64 *) memory loads, three of which will fail. Using
barrier_var() forces Clang to apply BYTE_OFFSET relocation first (and once) to
calculate p, after which value of p is used without relocation in each of
switch case arms, doing appropiately-sized memory load.

Here's the list of relevant relocations and pieces of generated BPF code
before and after this patch for test_core_reloc_bitfields_direct selftests.

BEFORE
=====
 Freescale#45: core_reloc: insn Freescale#160 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32
 Freescale#46: core_reloc: insn Freescale#167 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#47: core_reloc: insn Freescale#174 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#48: core_reloc: insn Freescale#178 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#49: core_reloc: insn Freescale#182 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32

     157:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     159:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     160:       b7 02 00 00 04 00 00 00 r2 = 4
; BYTE_SIZE relocation here                 ^^^
     161:       66 02 07 00 03 00 00 00 if w2 s> 3 goto +7 <LBB0_63>
     162:       16 02 0d 00 01 00 00 00 if w2 == 1 goto +13 <LBB0_65>
     163:       16 02 01 00 02 00 00 00 if w2 == 2 goto +1 <LBB0_66>
     164:       05 00 12 00 00 00 00 00 goto +18 <LBB0_69>

0000000000000528 <LBB0_66>:
     165:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     167:       69 11 08 00 00 00 00 00 r1 = *(u16 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     168:       05 00 0e 00 00 00 00 00 goto +14 <LBB0_69>

0000000000000548 <LBB0_63>:
     169:       16 02 0a 00 04 00 00 00 if w2 == 4 goto +10 <LBB0_67>
     170:       16 02 01 00 08 00 00 00 if w2 == 8 goto +1 <LBB0_68>
     171:       05 00 0b 00 00 00 00 00 goto +11 <LBB0_69>

0000000000000560 <LBB0_68>:
     172:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     174:       79 11 08 00 00 00 00 00 r1 = *(u64 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     175:       05 00 07 00 00 00 00 00 goto +7 <LBB0_69>

0000000000000580 <LBB0_65>:
     176:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     178:       71 11 08 00 00 00 00 00 r1 = *(u8 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     179:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

00000000000005a0 <LBB0_67>:
     180:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     182:       61 11 08 00 00 00 00 00 r1 = *(u32 *)(r1 + 8)
; BYTE_OFFSET relo here w/ RIGHT size        ^^^^^^^^^^^^^^^^

00000000000005b8 <LBB0_69>:
     183:       67 01 00 00 20 00 00 00 r1 <<= 32
     184:       b7 02 00 00 00 00 00 00 r2 = 0
     185:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     186:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     187:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000005e0 <LBB0_71>:
     188:       77 01 00 00 20 00 00 00 r1 >>= 32

AFTER
=====

 Freescale#30: core_reloc: insn Freescale#132 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 Freescale#31: core_reloc: insn Freescale#134 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32

     129:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     131:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     132:       b7 01 00 00 08 00 00 00 r1 = 8
; BYTE_OFFSET relo here                     ^^^
; no size check for non-memory dereferencing instructions
     133:       0f 12 00 00 00 00 00 00 r2 += r1
     134:       b7 03 00 00 04 00 00 00 r3 = 4
; BYTE_SIZE relocation here                 ^^^
     135:       66 03 05 00 03 00 00 00 if w3 s> 3 goto +5 <LBB0_63>
     136:       16 03 09 00 01 00 00 00 if w3 == 1 goto +9 <LBB0_65>
     137:       16 03 01 00 02 00 00 00 if w3 == 2 goto +1 <LBB0_66>
     138:       05 00 0a 00 00 00 00 00 goto +10 <LBB0_69>

0000000000000458 <LBB0_66>:
     139:       69 21 00 00 00 00 00 00 r1 = *(u16 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     140:       05 00 08 00 00 00 00 00 goto +8 <LBB0_69>

0000000000000468 <LBB0_63>:
     141:       16 03 06 00 04 00 00 00 if w3 == 4 goto +6 <LBB0_67>
     142:       16 03 01 00 08 00 00 00 if w3 == 8 goto +1 <LBB0_68>
     143:       05 00 05 00 00 00 00 00 goto +5 <LBB0_69>

0000000000000480 <LBB0_68>:
     144:       79 21 00 00 00 00 00 00 r1 = *(u64 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     145:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

0000000000000490 <LBB0_65>:
     146:       71 21 00 00 00 00 00 00 r1 = *(u8 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     147:       05 00 01 00 00 00 00 00 goto +1 <LBB0_69>

00000000000004a0 <LBB0_67>:
     148:       61 21 00 00 00 00 00 00 r1 = *(u32 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^

00000000000004a8 <LBB0_69>:
     149:       67 01 00 00 20 00 00 00 r1 <<= 32
     150:       b7 02 00 00 00 00 00 00 r2 = 0
     151:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     152:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     153:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000004d0 <LBB0_71>:
     154:       77 01 00 00 20 00 00 00 r1 >>= 323

Fixes: ee26dad ("libbpf: Add support for relocatable bitfields")
Signed-off-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Lorenz Bauer <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request May 22, 2021
[ Upstream commit d5027ca ]

Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 Freescale#26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 Freescale#27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 Freescale#28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 Freescale#40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 Freescale#44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 Freescale#45 0x00007f8990968b85 in __getgrnam_r [...]
 Freescale#46 0x00007f89909d6b77 in grantpt [...]
 Freescale#47 0x00007f8990a9394e in __GI_openpty [...]
 Freescale#48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 Freescale#49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 Freescale#50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 Freescale#51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 Freescale#52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
Acked-By: Anton Ivanov <[email protected]>
Tested-By: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request May 22, 2021
[ Upstream commit d5027ca ]

Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 Freescale#26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 Freescale#27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 Freescale#28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 Freescale#40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 Freescale#44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 Freescale#45 0x00007f8990968b85 in __getgrnam_r [...]
 Freescale#46 0x00007f89909d6b77 in grantpt [...]
 Freescale#47 0x00007f8990a9394e in __GI_openpty [...]
 Freescale#48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 Freescale#49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 Freescale#50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 Freescale#51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 Freescale#52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
Acked-By: Anton Ivanov <[email protected]>
Tested-By: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request May 22, 2021
[ Upstream commit d5027ca ]

Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 Freescale#26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 Freescale#27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 Freescale#28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 Freescale#40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 Freescale#44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 Freescale#45 0x00007f8990968b85 in __getgrnam_r [...]
 Freescale#46 0x00007f89909d6b77 in grantpt [...]
 Freescale#47 0x00007f8990a9394e in __GI_openpty [...]
 Freescale#48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 Freescale#49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 Freescale#50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 Freescale#51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 Freescale#52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
Acked-By: Anton Ivanov <[email protected]>
Tested-By: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Jul 20, 2021
commit 7c6986a upstream.

In raise_backtrace_ipi() we iterate through the cpumask of CPUs, sending
each an IPI asking them to do a backtrace, but we don't wait for the
backtrace to happen.

We then iterate through the CPU mask again, and if any CPU hasn't done
the backtrace and cleared itself from the mask, we print a trace on its
behalf, noting that the trace may be "stale".

This works well enough when a CPU is not responding, because in that
case it doesn't receive the IPI and the sending CPU is left to print the
trace. But when all CPUs are responding we are left with a race between
the sending and receiving CPUs, if the sending CPU wins the race then it
will erroneously print a trace.

This leads to spurious "stale" traces from the sending CPU, which can
then be interleaved messily with the receiving CPU, note the CPU
numbers, eg:

  [ 1658.929157][    C7] rcu: Stack dump where RCU GP kthread last ran:
  [ 1658.929223][    C7] Sending NMI from CPU 7 to CPUs 1:
  [ 1658.929303][    C1] NMI backtrace for cpu 1
  [ 1658.929303][    C7] CPU 1 didn't respond to backtrace IPI, inspecting paca.
  [ 1658.929362][    C1] CPU: 1 PID: 325 Comm: kworker/1:1H Tainted: G        W   E     5.13.0-rc2+ Freescale#46
  [ 1658.929405][    C7] irq_soft_mask: 0x01 in_mce: 0 in_nmi: 0 current: 325 (kworker/1:1H)
  [ 1658.929465][    C1] Workqueue: events_highpri test_work_fn [test_lockup]
  [ 1658.929549][    C7] Back trace of paca->saved_r1 (0xc0000000057fb400) (possibly stale):
  [ 1658.929592][    C1] NIP:  c00000000002cf50 LR: c008000000820178 CTR: c00000000002cfa0

To fix it, change the logic so that the sending CPU waits 5s for the
receiving CPU to print its trace. If the receiving CPU prints its trace
successfully then the sending CPU just continues, avoiding any spurious
"stale" trace.

This has the added benefit of allowing all CPUs to print their traces in
order and avoids any interleaving of their output.

Fixes: 5cc0591 ("powerpc/64s: Wire up arch_trigger_cpumask_backtrace()")
Cc: [email protected] # v4.18+
Reported-by: Nathan Lynch <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Jul 20, 2021
commit 7c6986a upstream.

In raise_backtrace_ipi() we iterate through the cpumask of CPUs, sending
each an IPI asking them to do a backtrace, but we don't wait for the
backtrace to happen.

We then iterate through the CPU mask again, and if any CPU hasn't done
the backtrace and cleared itself from the mask, we print a trace on its
behalf, noting that the trace may be "stale".

This works well enough when a CPU is not responding, because in that
case it doesn't receive the IPI and the sending CPU is left to print the
trace. But when all CPUs are responding we are left with a race between
the sending and receiving CPUs, if the sending CPU wins the race then it
will erroneously print a trace.

This leads to spurious "stale" traces from the sending CPU, which can
then be interleaved messily with the receiving CPU, note the CPU
numbers, eg:

  [ 1658.929157][    C7] rcu: Stack dump where RCU GP kthread last ran:
  [ 1658.929223][    C7] Sending NMI from CPU 7 to CPUs 1:
  [ 1658.929303][    C1] NMI backtrace for cpu 1
  [ 1658.929303][    C7] CPU 1 didn't respond to backtrace IPI, inspecting paca.
  [ 1658.929362][    C1] CPU: 1 PID: 325 Comm: kworker/1:1H Tainted: G        W   E     5.13.0-rc2+ Freescale#46
  [ 1658.929405][    C7] irq_soft_mask: 0x01 in_mce: 0 in_nmi: 0 current: 325 (kworker/1:1H)
  [ 1658.929465][    C1] Workqueue: events_highpri test_work_fn [test_lockup]
  [ 1658.929549][    C7] Back trace of paca->saved_r1 (0xc0000000057fb400) (possibly stale):
  [ 1658.929592][    C1] NIP:  c00000000002cf50 LR: c008000000820178 CTR: c00000000002cfa0

To fix it, change the logic so that the sending CPU waits 5s for the
receiving CPU to print its trace. If the receiving CPU prints its trace
successfully then the sending CPU just continues, avoiding any spurious
"stale" trace.

This has the added benefit of allowing all CPUs to print their traces in
order and avoids any interleaving of their output.

Fixes: 5cc0591 ("powerpc/64s: Wire up arch_trigger_cpumask_backtrace()")
Cc: [email protected] # v4.18+
Reported-by: Nathan Lynch <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Jul 20, 2021
commit 7c6986a upstream.

In raise_backtrace_ipi() we iterate through the cpumask of CPUs, sending
each an IPI asking them to do a backtrace, but we don't wait for the
backtrace to happen.

We then iterate through the CPU mask again, and if any CPU hasn't done
the backtrace and cleared itself from the mask, we print a trace on its
behalf, noting that the trace may be "stale".

This works well enough when a CPU is not responding, because in that
case it doesn't receive the IPI and the sending CPU is left to print the
trace. But when all CPUs are responding we are left with a race between
the sending and receiving CPUs, if the sending CPU wins the race then it
will erroneously print a trace.

This leads to spurious "stale" traces from the sending CPU, which can
then be interleaved messily with the receiving CPU, note the CPU
numbers, eg:

  [ 1658.929157][    C7] rcu: Stack dump where RCU GP kthread last ran:
  [ 1658.929223][    C7] Sending NMI from CPU 7 to CPUs 1:
  [ 1658.929303][    C1] NMI backtrace for cpu 1
  [ 1658.929303][    C7] CPU 1 didn't respond to backtrace IPI, inspecting paca.
  [ 1658.929362][    C1] CPU: 1 PID: 325 Comm: kworker/1:1H Tainted: G        W   E     5.13.0-rc2+ Freescale#46
  [ 1658.929405][    C7] irq_soft_mask: 0x01 in_mce: 0 in_nmi: 0 current: 325 (kworker/1:1H)
  [ 1658.929465][    C1] Workqueue: events_highpri test_work_fn [test_lockup]
  [ 1658.929549][    C7] Back trace of paca->saved_r1 (0xc0000000057fb400) (possibly stale):
  [ 1658.929592][    C1] NIP:  c00000000002cf50 LR: c008000000820178 CTR: c00000000002cfa0

To fix it, change the logic so that the sending CPU waits 5s for the
receiving CPU to print its trace. If the receiving CPU prints its trace
successfully then the sending CPU just continues, avoiding any spurious
"stale" trace.

This has the added benefit of allowing all CPUs to print their traces in
order and avoids any interleaving of their output.

Fixes: 5cc0591 ("powerpc/64s: Wire up arch_trigger_cpumask_backtrace()")
Cc: [email protected] # v4.18+
Reported-by: Nathan Lynch <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Jan 4, 2022
[ Upstream commit ffb76a8 ]

Hi,

When testing install and uninstall of ipmi_si.ko and ipmi_msghandler.ko,
the system crashed.

The log as follows:
[  141.087026] BUG: unable to handle kernel paging request at ffffffffc09b3a5a
[  141.087241] PGD 8fe4c0d067 P4D 8fe4c0d067 PUD 8fe4c0f067 PMD 103ad89067 PTE 0
[  141.087464] Oops: 0010 [Freescale#1] SMP NOPTI
[  141.087580] CPU: 67 PID: 668 Comm: kworker/67:1 Kdump: loaded Not tainted 4.18.0.x86_64 Freescale#47
[  141.088009] Workqueue: events 0xffffffffc09b3a40
[  141.088009] RIP: 0010:0xffffffffc09b3a5a
[  141.088009] Code: Bad RIP value.
[  141.088009] RSP: 0018:ffffb9094e2c3e88 EFLAGS: 00010246
[  141.088009] RAX: 0000000000000000 RBX: ffff9abfdb1f04a0 RCX: 0000000000000000
[  141.088009] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  141.088009] RBP: 0000000000000000 R08: ffff9abfffee3cb8 R09: 00000000000002e1
[  141.088009] R10: ffffb9094cb73d90 R11: 00000000000f4240 R12: ffff9abfffee8700
[  141.088009] R13: 0000000000000000 R14: ffff9abfdb1f04a0 R15: ffff9abfdb1f04a8
[  141.088009] FS:  0000000000000000(0000) GS:ffff9abfffec0000(0000) knlGS:0000000000000000
[  141.088009] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  141.088009] CR2: ffffffffc09b3a30 CR3: 0000008fe4c0a001 CR4: 00000000007606e0
[  141.088009] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  141.088009] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  141.088009] PKRU: 55555554
[  141.088009] Call Trace:
[  141.088009]  ? process_one_work+0x195/0x390
[  141.088009]  ? worker_thread+0x30/0x390
[  141.088009]  ? process_one_work+0x390/0x390
[  141.088009]  ? kthread+0x10d/0x130
[  141.088009]  ? kthread_flush_work_fn+0x10/0x10
[  141.088009]  ? ret_from_fork+0x35/0x40] BUG: unable to handle kernel paging request at ffffffffc0b28a5a
[  200.223240] PGD 97fe00d067 P4D 97fe00d067 PUD 97fe00f067 PMD a580cbf067 PTE 0
[  200.223464] Oops: 0010 [Freescale#1] SMP NOPTI
[  200.223579] CPU: 63 PID: 664 Comm: kworker/63:1 Kdump: loaded Not tainted 4.18.0.x86_64 Freescale#46
[  200.224008] Workqueue: events 0xffffffffc0b28a40
[  200.224008] RIP: 0010:0xffffffffc0b28a5a
[  200.224008] Code: Bad RIP value.
[  200.224008] RSP: 0018:ffffbf3c8e2a3e88 EFLAGS: 00010246
[  200.224008] RAX: 0000000000000000 RBX: ffffa0799ad6bca0 RCX: 0000000000000000
[  200.224008] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  200.224008] RBP: 0000000000000000 R08: ffff9fe43fde3cb8 R09: 00000000000000d5
[  200.224008] R10: ffffbf3c8cb53d90 R11: 00000000000f4240 R12: ffff9fe43fde8700
[  200.224008] R13: 0000000000000000 R14: ffffa0799ad6bca0 R15: ffffa0799ad6bca8
[  200.224008] FS:  0000000000000000(0000) GS:ffff9fe43fdc0000(0000) knlGS:0000000000000000
[  200.224008] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  200.224008] CR2: ffffffffc0b28a30 CR3: 00000097fe00a002 CR4: 00000000007606e0
[  200.224008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  200.224008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  200.224008] PKRU: 55555554
[  200.224008] Call Trace:
[  200.224008]  ? process_one_work+0x195/0x390
[  200.224008]  ? worker_thread+0x30/0x390
[  200.224008]  ? process_one_work+0x390/0x390
[  200.224008]  ? kthread+0x10d/0x130
[  200.224008]  ? kthread_flush_work_fn+0x10/0x10
[  200.224008]  ? ret_from_fork+0x35/0x40
[  200.224008] kernel fault(0x1) notification starting on CPU 63
[  200.224008] kernel fault(0x1) notification finished on CPU 63
[  200.224008] CR2: ffffffffc0b28a5a
[  200.224008] ---[ end trace c82a412d93f57412 ]---

The reason is as follows:
T1: rmmod ipmi_si.
    ->ipmi_unregister_smi()
        -> ipmi_bmc_unregister()
            -> __ipmi_bmc_unregister()
                -> kref_put(&bmc->usecount, cleanup_bmc_device);
                    -> schedule_work(&bmc->remove_work);

T2: rmmod ipmi_msghandler.
    ipmi_msghander module uninstalled, and the module space
    will be freed.

T3: bmc->remove_work doing cleanup the bmc resource.
    -> cleanup_bmc_work()
        -> platform_device_unregister(&bmc->pdev);
            -> platform_device_del(pdev);
                -> device_del(&pdev->dev);
                    -> kobject_uevent(&dev->kobj, KOBJ_REMOVE);
                        -> kobject_uevent_env()
                            -> dev_uevent()
                                -> if (dev->type && dev->type->name)

   'dev->type'(bmc_device_type) pointer space has freed when uninstall
    ipmi_msghander module, 'dev->type->name' cause the system crash.

drivers/char/ipmi/ipmi_msghandler.c:
2820 static const struct device_type bmc_device_type = {
2821         .groups         = bmc_dev_attr_groups,
2822 };

Steps to reproduce:
Add a time delay in cleanup_bmc_work() function,
and uninstall ipmi_si and ipmi_msghandler module.

2910 static void cleanup_bmc_work(struct work_struct *work)
2911 {
2912         struct bmc_device *bmc = container_of(work, struct bmc_device,
2913                                               remove_work);
2914         int id = bmc->pdev.id; /* Unregister overwrites id */
2915
2916         msleep(3000);   <---
2917         platform_device_unregister(&bmc->pdev);
2918         ida_simple_remove(&ipmi_bmc_ida, id);
2919 }

Use 'remove_work_wq' instead of 'system_wq' to solve this issues.

Fixes: b2cfd8a ("ipmi: Rework device id and guid handling to catch changing BMCs")
Signed-off-by: Wu Bo <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Corey Minyard <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Jan 4, 2022
[ Upstream commit ffb76a8 ]

Hi,

When testing install and uninstall of ipmi_si.ko and ipmi_msghandler.ko,
the system crashed.

The log as follows:
[  141.087026] BUG: unable to handle kernel paging request at ffffffffc09b3a5a
[  141.087241] PGD 8fe4c0d067 P4D 8fe4c0d067 PUD 8fe4c0f067 PMD 103ad89067 PTE 0
[  141.087464] Oops: 0010 [Freescale#1] SMP NOPTI
[  141.087580] CPU: 67 PID: 668 Comm: kworker/67:1 Kdump: loaded Not tainted 4.18.0.x86_64 Freescale#47
[  141.088009] Workqueue: events 0xffffffffc09b3a40
[  141.088009] RIP: 0010:0xffffffffc09b3a5a
[  141.088009] Code: Bad RIP value.
[  141.088009] RSP: 0018:ffffb9094e2c3e88 EFLAGS: 00010246
[  141.088009] RAX: 0000000000000000 RBX: ffff9abfdb1f04a0 RCX: 0000000000000000
[  141.088009] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  141.088009] RBP: 0000000000000000 R08: ffff9abfffee3cb8 R09: 00000000000002e1
[  141.088009] R10: ffffb9094cb73d90 R11: 00000000000f4240 R12: ffff9abfffee8700
[  141.088009] R13: 0000000000000000 R14: ffff9abfdb1f04a0 R15: ffff9abfdb1f04a8
[  141.088009] FS:  0000000000000000(0000) GS:ffff9abfffec0000(0000) knlGS:0000000000000000
[  141.088009] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  141.088009] CR2: ffffffffc09b3a30 CR3: 0000008fe4c0a001 CR4: 00000000007606e0
[  141.088009] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  141.088009] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  141.088009] PKRU: 55555554
[  141.088009] Call Trace:
[  141.088009]  ? process_one_work+0x195/0x390
[  141.088009]  ? worker_thread+0x30/0x390
[  141.088009]  ? process_one_work+0x390/0x390
[  141.088009]  ? kthread+0x10d/0x130
[  141.088009]  ? kthread_flush_work_fn+0x10/0x10
[  141.088009]  ? ret_from_fork+0x35/0x40] BUG: unable to handle kernel paging request at ffffffffc0b28a5a
[  200.223240] PGD 97fe00d067 P4D 97fe00d067 PUD 97fe00f067 PMD a580cbf067 PTE 0
[  200.223464] Oops: 0010 [Freescale#1] SMP NOPTI
[  200.223579] CPU: 63 PID: 664 Comm: kworker/63:1 Kdump: loaded Not tainted 4.18.0.x86_64 Freescale#46
[  200.224008] Workqueue: events 0xffffffffc0b28a40
[  200.224008] RIP: 0010:0xffffffffc0b28a5a
[  200.224008] Code: Bad RIP value.
[  200.224008] RSP: 0018:ffffbf3c8e2a3e88 EFLAGS: 00010246
[  200.224008] RAX: 0000000000000000 RBX: ffffa0799ad6bca0 RCX: 0000000000000000
[  200.224008] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  200.224008] RBP: 0000000000000000 R08: ffff9fe43fde3cb8 R09: 00000000000000d5
[  200.224008] R10: ffffbf3c8cb53d90 R11: 00000000000f4240 R12: ffff9fe43fde8700
[  200.224008] R13: 0000000000000000 R14: ffffa0799ad6bca0 R15: ffffa0799ad6bca8
[  200.224008] FS:  0000000000000000(0000) GS:ffff9fe43fdc0000(0000) knlGS:0000000000000000
[  200.224008] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  200.224008] CR2: ffffffffc0b28a30 CR3: 00000097fe00a002 CR4: 00000000007606e0
[  200.224008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  200.224008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  200.224008] PKRU: 55555554
[  200.224008] Call Trace:
[  200.224008]  ? process_one_work+0x195/0x390
[  200.224008]  ? worker_thread+0x30/0x390
[  200.224008]  ? process_one_work+0x390/0x390
[  200.224008]  ? kthread+0x10d/0x130
[  200.224008]  ? kthread_flush_work_fn+0x10/0x10
[  200.224008]  ? ret_from_fork+0x35/0x40
[  200.224008] kernel fault(0x1) notification starting on CPU 63
[  200.224008] kernel fault(0x1) notification finished on CPU 63
[  200.224008] CR2: ffffffffc0b28a5a
[  200.224008] ---[ end trace c82a412d93f57412 ]---

The reason is as follows:
T1: rmmod ipmi_si.
    ->ipmi_unregister_smi()
        -> ipmi_bmc_unregister()
            -> __ipmi_bmc_unregister()
                -> kref_put(&bmc->usecount, cleanup_bmc_device);
                    -> schedule_work(&bmc->remove_work);

T2: rmmod ipmi_msghandler.
    ipmi_msghander module uninstalled, and the module space
    will be freed.

T3: bmc->remove_work doing cleanup the bmc resource.
    -> cleanup_bmc_work()
        -> platform_device_unregister(&bmc->pdev);
            -> platform_device_del(pdev);
                -> device_del(&pdev->dev);
                    -> kobject_uevent(&dev->kobj, KOBJ_REMOVE);
                        -> kobject_uevent_env()
                            -> dev_uevent()
                                -> if (dev->type && dev->type->name)

   'dev->type'(bmc_device_type) pointer space has freed when uninstall
    ipmi_msghander module, 'dev->type->name' cause the system crash.

drivers/char/ipmi/ipmi_msghandler.c:
2820 static const struct device_type bmc_device_type = {
2821         .groups         = bmc_dev_attr_groups,
2822 };

Steps to reproduce:
Add a time delay in cleanup_bmc_work() function,
and uninstall ipmi_si and ipmi_msghandler module.

2910 static void cleanup_bmc_work(struct work_struct *work)
2911 {
2912         struct bmc_device *bmc = container_of(work, struct bmc_device,
2913                                               remove_work);
2914         int id = bmc->pdev.id; /* Unregister overwrites id */
2915
2916         msleep(3000);   <---
2917         platform_device_unregister(&bmc->pdev);
2918         ida_simple_remove(&ipmi_bmc_ida, id);
2919 }

Use 'remove_work_wq' instead of 'system_wq' to solve this issues.

Fixes: b2cfd8a ("ipmi: Rework device id and guid handling to catch changing BMCs")
Signed-off-by: Wu Bo <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Corey Minyard <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Jan 4, 2022
[ Upstream commit ffb76a8 ]

Hi,

When testing install and uninstall of ipmi_si.ko and ipmi_msghandler.ko,
the system crashed.

The log as follows:
[  141.087026] BUG: unable to handle kernel paging request at ffffffffc09b3a5a
[  141.087241] PGD 8fe4c0d067 P4D 8fe4c0d067 PUD 8fe4c0f067 PMD 103ad89067 PTE 0
[  141.087464] Oops: 0010 [Freescale#1] SMP NOPTI
[  141.087580] CPU: 67 PID: 668 Comm: kworker/67:1 Kdump: loaded Not tainted 4.18.0.x86_64 Freescale#47
[  141.088009] Workqueue: events 0xffffffffc09b3a40
[  141.088009] RIP: 0010:0xffffffffc09b3a5a
[  141.088009] Code: Bad RIP value.
[  141.088009] RSP: 0018:ffffb9094e2c3e88 EFLAGS: 00010246
[  141.088009] RAX: 0000000000000000 RBX: ffff9abfdb1f04a0 RCX: 0000000000000000
[  141.088009] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  141.088009] RBP: 0000000000000000 R08: ffff9abfffee3cb8 R09: 00000000000002e1
[  141.088009] R10: ffffb9094cb73d90 R11: 00000000000f4240 R12: ffff9abfffee8700
[  141.088009] R13: 0000000000000000 R14: ffff9abfdb1f04a0 R15: ffff9abfdb1f04a8
[  141.088009] FS:  0000000000000000(0000) GS:ffff9abfffec0000(0000) knlGS:0000000000000000
[  141.088009] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  141.088009] CR2: ffffffffc09b3a30 CR3: 0000008fe4c0a001 CR4: 00000000007606e0
[  141.088009] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  141.088009] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  141.088009] PKRU: 55555554
[  141.088009] Call Trace:
[  141.088009]  ? process_one_work+0x195/0x390
[  141.088009]  ? worker_thread+0x30/0x390
[  141.088009]  ? process_one_work+0x390/0x390
[  141.088009]  ? kthread+0x10d/0x130
[  141.088009]  ? kthread_flush_work_fn+0x10/0x10
[  141.088009]  ? ret_from_fork+0x35/0x40] BUG: unable to handle kernel paging request at ffffffffc0b28a5a
[  200.223240] PGD 97fe00d067 P4D 97fe00d067 PUD 97fe00f067 PMD a580cbf067 PTE 0
[  200.223464] Oops: 0010 [Freescale#1] SMP NOPTI
[  200.223579] CPU: 63 PID: 664 Comm: kworker/63:1 Kdump: loaded Not tainted 4.18.0.x86_64 Freescale#46
[  200.224008] Workqueue: events 0xffffffffc0b28a40
[  200.224008] RIP: 0010:0xffffffffc0b28a5a
[  200.224008] Code: Bad RIP value.
[  200.224008] RSP: 0018:ffffbf3c8e2a3e88 EFLAGS: 00010246
[  200.224008] RAX: 0000000000000000 RBX: ffffa0799ad6bca0 RCX: 0000000000000000
[  200.224008] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  200.224008] RBP: 0000000000000000 R08: ffff9fe43fde3cb8 R09: 00000000000000d5
[  200.224008] R10: ffffbf3c8cb53d90 R11: 00000000000f4240 R12: ffff9fe43fde8700
[  200.224008] R13: 0000000000000000 R14: ffffa0799ad6bca0 R15: ffffa0799ad6bca8
[  200.224008] FS:  0000000000000000(0000) GS:ffff9fe43fdc0000(0000) knlGS:0000000000000000
[  200.224008] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  200.224008] CR2: ffffffffc0b28a30 CR3: 00000097fe00a002 CR4: 00000000007606e0
[  200.224008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  200.224008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  200.224008] PKRU: 55555554
[  200.224008] Call Trace:
[  200.224008]  ? process_one_work+0x195/0x390
[  200.224008]  ? worker_thread+0x30/0x390
[  200.224008]  ? process_one_work+0x390/0x390
[  200.224008]  ? kthread+0x10d/0x130
[  200.224008]  ? kthread_flush_work_fn+0x10/0x10
[  200.224008]  ? ret_from_fork+0x35/0x40
[  200.224008] kernel fault(0x1) notification starting on CPU 63
[  200.224008] kernel fault(0x1) notification finished on CPU 63
[  200.224008] CR2: ffffffffc0b28a5a
[  200.224008] ---[ end trace c82a412d93f57412 ]---

The reason is as follows:
T1: rmmod ipmi_si.
    ->ipmi_unregister_smi()
        -> ipmi_bmc_unregister()
            -> __ipmi_bmc_unregister()
                -> kref_put(&bmc->usecount, cleanup_bmc_device);
                    -> schedule_work(&bmc->remove_work);

T2: rmmod ipmi_msghandler.
    ipmi_msghander module uninstalled, and the module space
    will be freed.

T3: bmc->remove_work doing cleanup the bmc resource.
    -> cleanup_bmc_work()
        -> platform_device_unregister(&bmc->pdev);
            -> platform_device_del(pdev);
                -> device_del(&pdev->dev);
                    -> kobject_uevent(&dev->kobj, KOBJ_REMOVE);
                        -> kobject_uevent_env()
                            -> dev_uevent()
                                -> if (dev->type && dev->type->name)

   'dev->type'(bmc_device_type) pointer space has freed when uninstall
    ipmi_msghander module, 'dev->type->name' cause the system crash.

drivers/char/ipmi/ipmi_msghandler.c:
2820 static const struct device_type bmc_device_type = {
2821         .groups         = bmc_dev_attr_groups,
2822 };

Steps to reproduce:
Add a time delay in cleanup_bmc_work() function,
and uninstall ipmi_si and ipmi_msghandler module.

2910 static void cleanup_bmc_work(struct work_struct *work)
2911 {
2912         struct bmc_device *bmc = container_of(work, struct bmc_device,
2913                                               remove_work);
2914         int id = bmc->pdev.id; /* Unregister overwrites id */
2915
2916         msleep(3000);   <---
2917         platform_device_unregister(&bmc->pdev);
2918         ida_simple_remove(&ipmi_bmc_ida, id);
2919 }

Use 'remove_work_wq' instead of 'system_wq' to solve this issues.

Fixes: b2cfd8a ("ipmi: Rework device id and guid handling to catch changing BMCs")
Signed-off-by: Wu Bo <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Corey Minyard <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
LeBlue pushed a commit to LeBlue/linux-fslc that referenced this pull request Jan 20, 2022
[ Upstream commit d5027ca ]

Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 Freescale#26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 Freescale#27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 Freescale#28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 Freescale#40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 Freescale#44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 Freescale#45 0x00007f8990968b85 in __getgrnam_r [...]
 Freescale#46 0x00007f89909d6b77 in grantpt [...]
 Freescale#47 0x00007f8990a9394e in __GI_openpty [...]
 Freescale#48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 Freescale#49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 Freescale#50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 Freescale#51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 Freescale#52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
Acked-By: Anton Ivanov <[email protected]>
Tested-By: Ritesh Raj Sarraf <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Nov 28, 2023
[ Upstream commit 5104fdf ]

In certain types of chips, such as VEGA20, reading the amdgpu_regs_smc file could result in an abnormal null pointer access when the smc_rreg pointer is NULL. Below are the steps to reproduce this issue and the corresponding exception log:

1. Navigate to the directory: /sys/kernel/debug/dri/0
2. Execute command: cat amdgpu_regs_smc
3. Exception Log::
[4005007.702554] BUG: kernel NULL pointer dereference, address: 0000000000000000
[4005007.702562] #PF: supervisor instruction fetch in kernel mode
[4005007.702567] #PF: error_code(0x0010) - not-present page
[4005007.702570] PGD 0 P4D 0
[4005007.702576] Oops: 0010 [Freescale#1] SMP NOPTI
[4005007.702581] CPU: 4 PID: 62563 Comm: cat Tainted: G           OE     5.15.0-43-generic Freescale#46-Ubunt       u
[4005007.702590] RIP: 0010:0x0
[4005007.702598] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[4005007.702600] RSP: 0018:ffffa82b46d27da0 EFLAGS: 00010206
[4005007.702605] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffa82b46d27e68
[4005007.702609] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9940656e0000
[4005007.702612] RBP: ffffa82b46d27dd8 R08: 0000000000000000 R09: ffff994060c07980
[4005007.702615] R10: 0000000000020000 R11: 0000000000000000 R12: 00007f5e06753000
[4005007.702618] R13: ffff9940656e0000 R14: ffffa82b46d27e68 R15: 00007f5e06753000
[4005007.702622] FS:  00007f5e0755b740(0000) GS:ffff99479d300000(0000) knlGS:0000000000000000
[4005007.702626] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[4005007.702629] CR2: ffffffffffffffd6 CR3: 00000003253fc000 CR4: 00000000003506e0
[4005007.702633] Call Trace:
[4005007.702636]  <TASK>
[4005007.702640]  amdgpu_debugfs_regs_smc_read+0xb0/0x120 [amdgpu]
[4005007.703002]  full_proxy_read+0x5c/0x80
[4005007.703011]  vfs_read+0x9f/0x1a0
[4005007.703019]  ksys_read+0x67/0xe0
[4005007.703023]  __x64_sys_read+0x19/0x20
[4005007.703028]  do_syscall_64+0x5c/0xc0
[4005007.703034]  ? do_user_addr_fault+0x1e3/0x670
[4005007.703040]  ? exit_to_user_mode_prepare+0x37/0xb0
[4005007.703047]  ? irqentry_exit_to_user_mode+0x9/0x20
[4005007.703052]  ? irqentry_exit+0x19/0x30
[4005007.703057]  ? exc_page_fault+0x89/0x160
[4005007.703062]  ? asm_exc_page_fault+0x8/0x30
[4005007.703068]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[4005007.703075] RIP: 0033:0x7f5e07672992
[4005007.703079] Code: c0 e9 b2 fe ff ff 50 48 8d 3d fa b2 0c 00 e8 c5 1d 02 00 0f 1f 44 00 00 f3 0f        1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 e       c 28 48 89 54 24
[4005007.703083] RSP: 002b:00007ffe03097898 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[4005007.703088] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f5e07672992
[4005007.703091] RDX: 0000000000020000 RSI: 00007f5e06753000 RDI: 0000000000000003
[4005007.703094] RBP: 00007f5e06753000 R08: 00007f5e06752010 R09: 00007f5e06752010
[4005007.703096] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000022000
[4005007.703099] R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
[4005007.703105]  </TASK>
[4005007.703107] Modules linked in: nf_tables libcrc32c nfnetlink algif_hash af_alg binfmt_misc nls_       iso8859_1 ipmi_ssif ast intel_rapl_msr intel_rapl_common drm_vram_helper drm_ttm_helper amd64_edac t       tm edac_mce_amd kvm_amd ccp mac_hid k10temp kvm acpi_ipmi ipmi_si rapl sch_fq_codel ipmi_devintf ipm       i_msghandler msr parport_pc ppdev lp parport mtd pstore_blk efi_pstore ramoops pstore_zone reed_solo       mon ip_tables x_tables autofs4 ib_uverbs ib_core amdgpu(OE) amddrm_ttm_helper(OE) amdttm(OE) iommu_v       2 amd_sched(OE) amdkcl(OE) drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec rc_core        drm igb ahci xhci_pci libahci i2c_piix4 i2c_algo_bit xhci_pci_renesas dca
[4005007.703184] CR2: 0000000000000000
[4005007.703188] ---[ end trace ac65a538d240da39 ]---
[4005007.800865] RIP: 0010:0x0
[4005007.800871] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[4005007.800874] RSP: 0018:ffffa82b46d27da0 EFLAGS: 00010206
[4005007.800878] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffa82b46d27e68
[4005007.800881] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9940656e0000
[4005007.800883] RBP: ffffa82b46d27dd8 R08: 0000000000000000 R09: ffff994060c07980
[4005007.800886] R10: 0000000000020000 R11: 0000000000000000 R12: 00007f5e06753000
[4005007.800888] R13: ffff9940656e0000 R14: ffffa82b46d27e68 R15: 00007f5e06753000
[4005007.800891] FS:  00007f5e0755b740(0000) GS:ffff99479d300000(0000) knlGS:0000000000000000
[4005007.800895] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[4005007.800898] CR2: ffffffffffffffd6 CR3: 00000003253fc000 CR4: 00000000003506e0

Signed-off-by: Qu Huang <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
zandrey pushed a commit to zandrey/linux-fslc that referenced this pull request Feb 8, 2025
[ Upstream commit 3fff5da ]

Prevent adding a device which is already a team device lower,
e.g. adding veth0 if vlan1 was already added and veth0 is a lower of
vlan1.

This is not useful in practice and can lead to recursive locking:

$ ip link add veth0 type veth peer name veth1
$ ip link set veth0 up
$ ip link set veth1 up
$ ip link add link veth0 name veth0.1 type vlan protocol 802.1Q id 1
$ ip link add team0 type team
$ ip link set veth0.1 down
$ ip link set veth0.1 master team0
team0: Port device veth0.1 added
$ ip link set veth0 down
$ ip link set veth0 master team0

============================================
WARNING: possible recursive locking detected
6.13.0-rc2-virtme-00441-ga14a429069bb Freescale#46 Not tainted
--------------------------------------------
ip/7684 is trying to acquire lock:
ffff888016848e00 (team->team_lock_key){+.+.}-{4:4}, at: team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)

but task is already holding lock:
ffff888016848e00 (team->team_lock_key){+.+.}-{4:4}, at: team_add_slave (drivers/net/team/team_core.c:1147 drivers/net/team/team_core.c:1977)

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
----
lock(team->team_lock_key);
lock(team->team_lock_key);

*** DEADLOCK ***

May be due to missing lock nesting notation

2 locks held by ip/7684:

stack backtrace:
CPU: 3 UID: 0 PID: 7684 Comm: ip Not tainted 6.13.0-rc2-virtme-00441-ga14a429069bb Freescale#46
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:122)
print_deadlock_bug.cold (kernel/locking/lockdep.c:3040)
__lock_acquire (kernel/locking/lockdep.c:3893 kernel/locking/lockdep.c:5226)
? netlink_broadcast_filtered (net/netlink/af_netlink.c:1548)
lock_acquire.part.0 (kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851)
? team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)
? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 2))
? team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)
? lock_acquire (kernel/locking/lockdep.c:5822)
? team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)
__mutex_lock (kernel/locking/mutex.c:587 kernel/locking/mutex.c:735)
? team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)
? team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)
? fib_sync_up (net/ipv4/fib_semantics.c:2167)
? team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)
team_device_event (drivers/net/team/team_core.c:2928 drivers/net/team/team_core.c:2951 drivers/net/team/team_core.c:2973)
notifier_call_chain (kernel/notifier.c:85)
call_netdevice_notifiers_info (net/core/dev.c:1996)
__dev_notify_flags (net/core/dev.c:8993)
? __dev_change_flags (net/core/dev.c:8975)
dev_change_flags (net/core/dev.c:9027)
vlan_device_event (net/8021q/vlan.c:85 net/8021q/vlan.c:470)
? br_device_event (net/bridge/br.c:143)
notifier_call_chain (kernel/notifier.c:85)
call_netdevice_notifiers_info (net/core/dev.c:1996)
dev_open (net/core/dev.c:1519 net/core/dev.c:1505)
team_add_slave (drivers/net/team/team_core.c:1219 drivers/net/team/team_core.c:1977)
? __pfx_team_add_slave (drivers/net/team/team_core.c:1972)
do_set_master (net/core/rtnetlink.c:2917)
do_setlink.isra.0 (net/core/rtnetlink.c:3117)

Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=3c47b5843403a45aef57
Fixes: 3d249d4 ("net: introduce ethernet teaming device")
Signed-off-by: Octavian Purdila <[email protected]>
Reviewed-by: Hangbin Liu <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
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