Hi Davidlohr and Paul,
On 2016/3/3 9:37, Kefeng Wang wrote:
>
>
> On 2016/3/3 5:12, Paul E. McKenney wrote:
>> On Wed, Mar 02, 2016 at 11:55:43AM -0800, Davidlohr Bueso wrote:
>>> On Tue, 02 Feb 2016, Davidlohr Bueso wrote:
>>>
>>> I've just hit this issue myself and remembered this thread :)
>>>
>>> Paul, folks, does the below patch look reasonable to you? If so
>>> I can properly resend. thanks.
>>
>> If it works for Kefeng Wang, I would be happy to take it.
>
> Yes, it works for me, tested on my board.
>
Even if we merge Davidlohr's patch, I think we still need my v2 patch,
here is a scene,
----------
cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL);
if (cxt.lwsa == NULL) {
goto unwind;
}
or
cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL);
if (cxt.lrsa == NULL) {
VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory");
firsterr = -ENOMEM;
kfree(cxt.lwsa);
goto unwind;
}
----------
we will get cxt.lwsa = NULL, and go to cleanup, then in
static void __torture_print_stats(char *page,
struct lock_stress_stats *statp, bool write)
{
bool fail = 0;
int i, n_stress;
long max = 0;
long min = statp[0].n_lock_acquired; // here, *we will meet NULL
pointer dereference*
}
and my patch v2 solve this issue too, so it is still needed.
Thanks,
Kefeng
>
>>
>> Thanx, Paul
>>
>
