Re: [PATCH 1/7] mm: fix the deadlock in finish_fault()

From: Qi Zheng
Date: Tue Jul 20 2021 - 22:23:00 EST




On 7/21/21 7:14 AM, Andrew Morton wrote:
On Mon, 19 Jul 2021 17:53:12 +0800 Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> wrote:



On 7/19/21 5:28 AM, Kirill A. Shutemov wrote:
On Sun, Jul 18, 2021 at 12:30:27PM +0800, Qi Zheng wrote:
The commit 63f3655f9501(mm, memcg: fix reclaim deadlock with writeback)
fix a deadlock bug by pre-allocating the pte page table outside of the
page lock, the commit f9ce0be71d1f(mm: Cleanup faultaround and
finish_fault() codepaths) rework the relevant code but ignore this race,
fix it.

Fixes: f9ce0be71d1f(mm: Cleanup faultaround and finish_fault() codepaths)
Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>

Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>

and add stable@, please.


OK, I will add these in the patch v2, thanks.

Please send this as a separate standalone patch, not as a part of the
main series.

Also, please include in the changelog a description of the user-visible
impact of the bug which is being fixed.


OK, I will do this.

Thanks,
Qi