lkml.org 
[lkml]   [2012]   [Jan]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Patch] lkdtm: avoid calling lkdtm_do_action() with spin lock held
On 01/28/2012 08:52 PM, Cong Wang wrote:

> lkdtm_do_action() may call sleeping functions like kmalloc(),
> so do not call it with spin lock held.
>
> Cc: Prarit Bhargava <prarit@redhat.com>
> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>


Reviewed-by: Dave Young <dyoung@redhat.com>

>
> ---
> diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c
> index 150cd70..28adefe 100644
> --- a/drivers/misc/lkdtm.c
> +++ b/drivers/misc/lkdtm.c
> @@ -354,6 +354,7 @@ static void lkdtm_do_action(enum ctype which)
> static void lkdtm_handler(void)
> {
> unsigned long flags;
> + bool do_it = false;
>
> spin_lock_irqsave(&count_lock, flags);
> count--;
> @@ -361,10 +362,13 @@ static void lkdtm_handler(void)
> cp_name_to_str(cpoint), cp_type_to_str(cptype), count);
>
> if (count == 0) {
> - lkdtm_do_action(cptype);
> + do_it = true;
> count = cpoint_count;
> }
> spin_unlock_irqrestore(&count_lock, flags);
> +
> + if (do_it)
> + lkdtm_do_action(cptype);
> }
>
> static int lkdtm_register_cpoint(enum cname which)
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/



--
Thanks
Dave


\
 
 \ /
  Last update: 2012-01-29 02:15    [W:0.347 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site