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Test PR : Update README#37

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Test PR : Update README#37
sgaud-quic wants to merge 1 commit intoqualcomm-linux:tech/bsp/pinctrlfrom
sgaud-quic:tech/bsp/pinctrl

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Signed-off-by: sgaud-quic <sgaud@qti.qualcomm.com>
@sgaud-quic sgaud-quic closed this Jun 2, 2025
shashim-quic pushed a commit that referenced this pull request Aug 11, 2025
A kernel panic can be triggered by reading /proc/fs/cifs/debug_dirs.
The crash is a null-ptr-deref inside spin_lock(), caused by the use of the
uninitialized global spinlock cifs_tcp_ses_lock.

init_cifs()
 └── cifs_proc_init()
      └── // User can access /proc/fs/cifs/debug_dirs here
           └── cifs_debug_dirs_proc_show()
                └── spin_lock(&cifs_tcp_ses_lock); // Uninitialized!

KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
Mem abort info:
ESR = 0x0000000096000005
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x05: level 1 translation fault
Data abort info:
ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
CM = 0, WnR = 0, TnD = 0, TagAccess = 0
GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[dfff800000000000] address between user and kernel address ranges
Internal error: Oops: 0000000096000005 [#1] SMP
Modules linked in:
CPU: 3 UID: 0 PID: 16435 Comm: stress-ng-procf Not tainted 6.16.0-10385-g79f14b5d84c6 #37 PREEMPT
Hardware name: QEMU KVM Virtual Machine, BIOS 2025.02-8ubuntu1 06/11/2025
pstate: 23400005 (nzCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : do_raw_spin_lock+0x84/0x2cc
lr : _raw_spin_lock+0x24/0x34
sp : ffff8000966477e0
x29: ffff800096647860 x28: ffff800096647b88 x27: ffff0001c0c22070
x26: ffff0003eb2b60c8 x25: ffff0001c0c22018 x24: dfff800000000000
x23: ffff0000f624e000 x22: ffff0003eb2b6020 x21: ffff0000f624e768
x20: 0000000000000004 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000804b9600 x15: ffff700012cc8f04
x14: 1ffff00012cc8f04 x13: 0000000000000004 x12: ffffffffffffffff
x11: 1ffff00012cc8f00 x10: ffff80008d9af0d2 x9 : f3f3f304f1f1f1f1
x8 : 0000000000000000 x7 : 7365733c203e6469 x6 : 20656572743c2023
x5 : ffff0000e0ce0044 x4 : ffff80008a4deb6e x3 : ffff8000804b9718
x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
do_raw_spin_lock+0x84/0x2cc (P)
_raw_spin_lock+0x24/0x34
cifs_debug_dirs_proc_show+0x1ac/0x4c0
seq_read_iter+0x3b0/0xc28
proc_reg_read_iter+0x178/0x2a8
vfs_read+0x5f8/0x88c
ksys_read+0x120/0x210
__arm64_sys_read+0x7c/0x90
invoke_syscall+0x98/0x2b8
el0_svc_common+0x130/0x23c
do_el0_svc+0x48/0x58
el0_svc+0x40/0x140
el0t_64_sync_handler+0x84/0x12c
el0t_64_sync+0x1ac/0x1b0
Code: aa0003f3 f9000feb f2fe7e69 f8386969 (38f86908)
---[ end trace 0000000000000000 ]---

The root cause is an initialization order problem. The lock is declared
as a global variable and intended to be initialized during module startup.
However, the procfs entry that uses this lock can be accessed by userspace
before the spin_lock_init() call has run. This creates a race window where
reading the proc file will attempt to use the lock before it is
initialized, leading to the crash.

For a global lock with a static lifetime, the correct and robust approach
is to use compile-time initialization.

Fixes: 844e5c0 ("smb3 client: add way to show directory leases for improved debugging")
Signed-off-by: Yunseong Kim <ysk@kzalloc.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
loicpoulain pushed a commit that referenced this pull request Mar 2, 2026
[ Upstream commit 87bf646 ]

I encontered the following warning:
 WARNING: drivers/infiniband/sw/rxe/rxe_task.c:249 at rxe_sched_task+0x1c8/0x238 [rdma_rxe], CPU#0: swapper/0/0
...
  libsha1 [last unloaded: ip6_udp_tunnel]
 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G         C          6.19.0-rc5-64k-v8+ #37 PREEMPT
 Tainted: [C]=CRAP
 Hardware name: Raspberry Pi 4 Model B Rev 1.2
 Call trace:
  rxe_sched_task+0x1c8/0x238 [rdma_rxe] (P)
  retransmit_timer+0x130/0x188 [rdma_rxe]
  call_timer_fn+0x68/0x4d0
  __run_timers+0x630/0x888
...
 WARNING: drivers/infiniband/sw/rxe/rxe_task.c:38 at rxe_sched_task+0x1c0/0x238 [rdma_rxe], CPU#0: swapper/0/0
...
 WARNING: drivers/infiniband/sw/rxe/rxe_task.c:111 at do_work+0x488/0x5c8 [rdma_rxe], CPU#3: kworker/u17:4/93400
...
 refcount_t: underflow; use-after-free.
 WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x138/0x1a0, CPU#3: kworker/u17:4/93400

The issue is caused by a race condition between retransmit_timer() and
rxe_destroy_qp, leading to the Queue Pair's (QP) reference count dropping
to zero during timer handler execution.

It seems this warning is harmless because rxe_qp_do_cleanup() will flush
all pending timers and requests.

Example of flow causing the issue:

CPU0                                   CPU1
retransmit_timer() {
    spin_lock_irqsave
                           rxe_destroy_qp()
                            __rxe_cleanup()
                              __rxe_put() // qp->ref_count decrease to 0
                            rxe_qp_do_cleanup() {
    if (qp->valid) {
        rxe_sched_task() {
            WARN_ON(rxe_read(task->qp) <= 0);
        }
    }
    spin_unlock_irqrestore
}
                              spin_lock_irqsave
                              qp->valid = 0
                              spin_unlock_irqrestore
                            }

Ensure the QP's reference count is maintained and its validity is checked
within the timer callbacks by adding calls to rxe_get(qp) and corresponding
rxe_put(qp) after use.

Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Fixes: d946716 ("RDMA/rxe: Rewrite rxe_task.c")
Link: https://patch.msgid.link/20260120074437.623018-1-lizhijian@fujitsu.com
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sgaud-quic pushed a commit that referenced this pull request Mar 31, 2026
The napi_consume_skb() function is not intended to be called in an IRQ
disabled context. However, after commit 6bc8a50 ("net: macb: Fix
tx_ptr_lock locking"), the freeing of TX SKBs is performed with IRQs
disabled. To resolve the following call trace, use dev_consume_skb_any()
for freeing TX SKBs:
   WARNING: kernel/softirq.c:430 at __local_bh_enable_ip+0x174/0x188, CPU#0: ksoftirqd/0/15
   Modules linked in:
   CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 7.0.0-rc4-next-20260319-yocto-standard-dirty #37 PREEMPT
   Hardware name: ZynqMP ZCU102 Rev1.1 (DT)
   pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
   pc : __local_bh_enable_ip+0x174/0x188
   lr : local_bh_enable+0x24/0x38
   sp : ffff800082b3bb10
   x29: ffff800082b3bb10 x28: ffff0008031f3c00 x27: 000000000011ede0
   x26: ffff000800a7ff00 x25: ffff800083937ce8 x24: 0000000000017a80
   x23: ffff000803243a78 x22: 0000000000000040 x21: 0000000000000000
   x20: ffff000800394c80 x19: 0000000000000200 x18: 0000000000000001
   x17: 0000000000000001 x16: ffff000803240000 x15: 0000000000000000
   x14: ffffffffffffffff x13: 0000000000000028 x12: ffff000800395650
   x11: ffff8000821d1528 x10: ffff800081c2bc08 x9 : ffff800081c1e258
   x8 : 0000000100000301 x7 : ffff8000810426ec x6 : 0000000000000000
   x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000000
   x2 : 0000000000000008 x1 : 0000000000000200 x0 : ffff8000810428dc
   Call trace:
    __local_bh_enable_ip+0x174/0x188 (P)
    local_bh_enable+0x24/0x38
    skb_attempt_defer_free+0x190/0x1d8
    napi_consume_skb+0x58/0x108
    macb_tx_poll+0x1a4/0x558
    __napi_poll+0x50/0x198
    net_rx_action+0x1f4/0x3d8
    handle_softirqs+0x16c/0x560
    run_ksoftirqd+0x44/0x80
    smpboot_thread_fn+0x1d8/0x338
    kthread+0x120/0x150
    ret_from_fork+0x10/0x20
   irq event stamp: 29751
   hardirqs last  enabled at (29750): [<ffff8000813be184>] _raw_spin_unlock_irqrestore+0x44/0x88
   hardirqs last disabled at (29751): [<ffff8000813bdf60>] _raw_spin_lock_irqsave+0x38/0x98
   softirqs last  enabled at (29150): [<ffff8000800f1aec>] handle_softirqs+0x504/0x560
   softirqs last disabled at (29153): [<ffff8000800f2fec>] run_ksoftirqd+0x44/0x80

Fixes: 6bc8a50 ("net: macb: Fix tx_ptr_lock locking")
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260321-macb-tx-v1-1-b383a58dd4e6@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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