Re: [PATCH v4 26/54] scsi: fnic: Enable lock context analysis

[Nathan Chancellor <nathan@kernel.org>]

Hi Bart,

On Fri, Sep 25, 2026 at 11:26:04AM -0700, Bart Van Assche wrote:
> Document locking requirements with __must_hold(). Suppress complaints
> about conditional locking in fnic_device_reset() with __acquire() and
> __release().
> 
> Cc: Karan Tilak Kumar <kartilak@cisco.com>
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>

I am seeing the following warnings/errors with LLVM 23.1.3 after this
change in -next as commit 70d2304ae575 ("scsi: fnic: Enable lock context
analysis"):

  $ make -skj"$(nproc)" ARCH=x86_64 LLVM=1 mrproper allmodconfig drivers/scsi/fnic/
  drivers/scsi/fnic/fnic_nvme.c:1332:2: error: releasing spinlock 'iport->fnic->fnic_lock' that was not held [-Werror,-Wthread-safety-analysis]
   1332 |         spin_unlock_irqrestore(&fnic->fnic_lock, fnic->lock_flags);
        |         ^
  drivers/scsi/fnic/fnic_nvme.c:1336:1: error: spinlock 'iport->fnic->fnic_lock' is not held on every path through here [-Werror,-Wthread-safety-analysis]
   1336 | }
        | ^
  drivers/scsi/fnic/fnic_nvme.c:1335:2: note: spinlock acquired here
   1335 |         spin_lock_irqsave(&fnic->fnic_lock, fnic->lock_flags);
        |         ^
  include/linux/spinlock.h:389:35: note: expanded from macro 'spin_lock_irqsave'
    389 |         __release(spinlock_check(lock)); __acquire(lock);       \
        |                                          ^
  include/linux/compiler-context-analysis.h:375:23: note: expanded from macro '__acquire'
    375 | #define __acquire(x)            __acquire_ctx_lock(x)
        |                                 ^
  drivers/scsi/fnic/fnic_nvme.c:1445:2: error: releasing spinlock 'iport->fnic->fnic_lock' that was not held [-Werror,-Wthread-safety-analysis]
   1445 |         spin_unlock_irqrestore(&fnic->fnic_lock, fnic->lock_flags);
        |         ^
  drivers/scsi/fnic/fnic_nvme.c:1449:1: error: spinlock 'iport->fnic->fnic_lock' is not held on every path through here [-Werror,-Wthread-safety-analysis]
   1449 | }
        | ^
  drivers/scsi/fnic/fnic_nvme.c:1448:2: note: spinlock acquired here
   1448 |         spin_lock_irqsave(&fnic->fnic_lock, fnic->lock_flags);
        |         ^
  include/linux/spinlock.h:389:35: note: expanded from macro 'spin_lock_irqsave'
    389 |         __release(spinlock_check(lock)); __acquire(lock);       \
        |                                          ^
  include/linux/compiler-context-analysis.h:375:23: note: expanded from macro '__acquire'
    375 | #define __acquire(x)            __acquire_ctx_lock(x)
        |                                 ^
  drivers/scsi/fnic/fnic_nvme.c:2120:2: error: releasing spinlock 'iport->fnic->fnic_lock' that was not held [-Werror,-Wthread-safety-analysis]
   2120 |         spin_unlock_irqrestore(&fnic->fnic_lock, flags);
        |         ^
  drivers/scsi/fnic/fnic_nvme.c:2178:1: error: spinlock 'iport->fnic->fnic_lock' is not held on every path through here [-Werror,-Wthread-safety-analysis]
   2178 | }
        | ^
  drivers/scsi/fnic/fnic_nvme.c:2144:2: note: spinlock acquired here
   2144 |         spin_lock_irqsave(&fnic->fnic_lock, flags);
        |         ^
  include/linux/spinlock.h:389:35: note: expanded from macro 'spin_lock_irqsave'
    389 |         __release(spinlock_check(lock)); __acquire(lock);       \
        |                                          ^
  include/linux/compiler-context-analysis.h:375:23: note: expanded from macro '__acquire'
    375 | #define __acquire(x)            __acquire_ctx_lock(x)
        |                                 ^
  drivers/scsi/fnic/fnic_nvme.c:2199:2: error: releasing spinlock 'fnic->fnic_lock' that was not held [-Werror,-Wthread-safety-analysis]
   2199 |         spin_unlock_irqrestore(&fnic->fnic_lock, flags);
        |         ^
  drivers/scsi/fnic/fnic_nvme.c:2215:1: error: spinlock 'fnic->fnic_lock' is still held at the end of function [-Werror,-Wthread-safety-analysis]
   2215 | }
        | ^
  drivers/scsi/fnic/fnic_nvme.c:2202:2: note: spinlock acquired here
   2202 |         spin_lock_irqsave(&fnic->fnic_lock, flags);
        |         ^
  include/linux/spinlock.h:389:35: note: expanded from macro 'spin_lock_irqsave'
    389 |         __release(spinlock_check(lock)); __acquire(lock);       \
        |                                          ^
  include/linux/compiler-context-analysis.h:375:23: note: expanded from macro '__acquire'
    375 | #define __acquire(x)            __acquire_ctx_lock(x)
        |                                 ^
  8 errors generated.

-- 
Cheers,
Nathan