On 02/10/2019 09:52 PM, Alexei Starovoitov wrote:
> Lockdep warns about false positive:
> [ 11.211460] ------------[ cut here ]------------
> [ 11.211936] DEBUG_LOCKS_WARN_ON(depth <= 0)
> [ 11.211985] WARNING: CPU: 0 PID: 141 at ../kernel/locking/lockdep.c:3592
> lock_release+0x1ad/0x280
> [ 11.213134] Modules linked in:
> [ 11.214954] RIP: 0010:lock_release+0x1ad/0x280
> [ 11.223508] Call Trace:
> [ 11.223705] <IRQ>
> [ 11.223874] ? __local_bh_enable+0x7a/0x80
> [ 11.224199] up_read+0x1c/0xa0
> [ 11.224446] do_up_read+0x12/0x20
> [ 11.224713] irq_work_run_list+0x43/0x70
> [ 11.225030] irq_work_run+0x26/0x50
> [ 11.225310] smp_irq_work_interrupt+0x57/0x1f0
> [ 11.225662] irq_work_interrupt+0xf/0x20
>
> since rw_semaphore is released in a different task vs task that locked the
> sema.
> It is expected behavior.
> Fix the warning with up_read_non_owner() and rwsem_release() annotation.
>
> Fixes: bae77c5eb5b2 ("bpf: enable stackmap with build_id in nmi context")
> Signed-off-by: Alexei Starovoitov <[email protected]>
Applied, thanks!
