hi, Mel Gorman,
On Wed, Jul 06, 2022 at 10:55:35AM +0100, Mel Gorman wrote:
> On Tue, Jul 05, 2022 at 09:51:25PM +0800, Oliver Sang wrote:
> > Hi Andrew Morton,
> >
> > On Sun, Jul 03, 2022 at 01:22:09PM -0700, Andrew Morton wrote:
> > > On Sun, 3 Jul 2022 17:44:30 +0800 kernel test robot <oliver.sang@xxxxxxxxx> wrote:
> > >
> > > > FYI, we noticed the following commit (built with gcc-11):
> > > >
> > > > commit: 2bd8eec68f740608db5ea58ecff06965228764cb ("[PATCH 7/7] mm/page_alloc: Replace local_lock with normal spinlock")
> > > > url: https://github.com/intel-lab-lkp/linux/commits/Mel-Gorman/Drain-remote-per-cpu-directly/20220613-230139
> > > > base: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git b13baccc3850ca8b8cccbf8ed9912dbaa0fdf7f3
> > > > patch link: https://lore.kernel.org/lkml/20220613125622.18628-8-mgorman@xxxxxxxxxxxxxxxxxxx
> > > >
> > >
> > > Did this test include the followup patch
> > > mm-page_alloc-replace-local_lock-with-normal-spinlock-fix.patch?
> >
> > no, we just fetched original patch set and test upon it.
> >
> > now we applied the patch you pointed to us upon 2bd8eec68f and found the issue
> > still exist.
> > (attached dmesg FYI)
> >
>
> Thanks Oliver.
>
> The trace is odd in that it hits in GUP when the page allocator is no
> longer active and the context is a syscall. First, is this definitely
> the first patch the problem occurs?
>
> Second, it's possible for IRQs to be enabled and an IRQ delivered before
> preemption is enabled. It's not clear why that would be a problem other
> than lacking symmetry or how it could result in the reported BUG but
> might as well rule it out. This is build tested only
do you want us test below patch?
if so, should we apply it upon the patch
"mm/page_alloc: Replace local_lock with normal spinlock"
or
"mm/page_alloc: replace local_lock with normal spinlock -fix"?
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 934d1b5a5449..d0141e51e613 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -192,14 +192,14 @@ static DEFINE_MUTEX(pcp_batch_high_lock);
>
> #define pcpu_spin_unlock(member, ptr) \
> ({ \
> - spin_unlock(&ptr->member); \
> pcpu_task_unpin(); \
> + spin_unlock(&ptr->member); \
> })
>
> #define pcpu_spin_unlock_irqrestore(member, ptr, flags) \
> ({ \
> - spin_unlock_irqrestore(&ptr->member, flags); \
> pcpu_task_unpin(); \
> + spin_unlock_irqrestore(&ptr->member, flags); \
> })
>
> /* struct per_cpu_pages specific helpers. */
>
>
>
