Re: [PATCH] sample-trace-array: Fix sleeping function called from invalid context

[Steven Rostedt]

On Mon, 8 Jun 2020 07:54:37 +0000
Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:

>  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935
>  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/5
>  1 lock held by swapper/5/0:
>   #0: ffff80001002bd90 (samples/ftrace/sample-trace-array.c:38){+.-.}-{0:0}, at: call_timer_fn+0x8/0x3e0
>  CPU: 5 PID: 0 Comm: swapper/5 Not tainted 5.7.0+ #8
>  Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
>  Call trace:
>   dump_backtrace+0x0/0x1a0
>   show_stack+0x20/0x30
>   dump_stack+0xe4/0x150
>   ___might_sleep+0x160/0x200
>   __might_sleep+0x58/0x90
>   __mutex_lock+0x64/0x948
>   mutex_lock_nested+0x3c/0x58
>   __ftrace_set_clr_event+0x44/0x88
>   trace_array_set_clr_event+0x24/0x38
>   mytimer_handler+0x34/0x40 [sample_trace_array]
> 
> mutex_lock() will be called in interrupt context, using workqueueu to fix it.
> 
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
> 

Divya,

Can you give a Reviewed-by for this?

-- Steve