Re: [PATCH] tracing/rb: init the CPU mask on allocation

[Tetsuo Handa]

Sebastian Andrzej Siewior wrote:
> Before commit b32614c03413 ("tracing/rb: Convert to hotplug state
> machine") the allocated cpumask was initialized to the mask of ONLINE or
> POSSIBLE CPUs. After the CPU hotplug changes the buffer initialisation
> moved to trace_rb_cpu_prepare() but I forgot to initially set the
> cpumask to zero. This is done now.
> 
> Fixes: b32614c03413 ("tracing/rb: Convert to hotplug state machine")
> Reported-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>

The system can boot now. Thank you.

Tested-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>

> ---
>  kernel/trace/ring_buffer.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
> index 67da107e5712..a85739efcc30 100644
> --- a/kernel/trace/ring_buffer.c
> +++ b/kernel/trace/ring_buffer.c
> @@ -1297,7 +1297,7 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
>  	if (!buffer)
>  		return NULL;
>  
> -	if (!alloc_cpumask_var(&buffer->cpumask, GFP_KERNEL))
> +	if (!zalloc_cpumask_var(&buffer->cpumask, GFP_KERNEL))
>  		goto fail_free_buffer;
>  
>  	nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
> -- 
> 2.11.0