发件人: Matthew Wilcox <willy@xxxxxxxxxxxxx>
发送时间: 星期日, 七月 11, 2021 05:10
收件人: Andrew Morton
抄送: Zhang, Qiang; mgorman@xxxxxxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
主题: Re: [PATCH] mm/page_alloc: avoid hard lockups in __alloc_pages_bulk()
发送时间: 星期日, 七月 11, 2021 05:10
收件人: Andrew Morton
抄送: Zhang, Qiang; mgorman@xxxxxxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
主题: Re: [PATCH] mm/page_alloc: avoid hard lockups in __alloc_pages_bulk()
[Please note: This e-mail is from an EXTERNAL e-mail address]
On Sat, Jul 10, 2021 at 11:46:13AM -0700, Andrew Morton wrote:
> On Sat, 10 Jul 2021 19:29:29 +0800 qiang.zhang@xxxxxxxxxxxxx wrote:
>
> > From: Zqiang <qiang.zhang@xxxxxxxxxxxxx>
> >
> > The __alloc_pages_bulk() mainly used for batch allocation of
> > order-0 pages, in the case of holding pagesets.lock, if too
> > many pages are required, maybe trigger hard lockup watchdog.
>
> Ouch. Has this been observed in testing? If so, can you please share
> the kernel debug output from that event?
>This should be fixed in the caller by asking for fewer pages.
>The NFS and vmalloc cases have already been fixed for this.
On Sat, Jul 10, 2021 at 11:46:13AM -0700, Andrew Morton wrote:
> On Sat, 10 Jul 2021 19:29:29 +0800 qiang.zhang@xxxxxxxxxxxxx wrote:
>
> > From: Zqiang <qiang.zhang@xxxxxxxxxxxxx>
> >
> > The __alloc_pages_bulk() mainly used for batch allocation of
> > order-0 pages, in the case of holding pagesets.lock, if too
> > many pages are required, maybe trigger hard lockup watchdog.
>
> Ouch. Has this been observed in testing? If so, can you please share
> the kernel debug output from that event?
>This should be fixed in the caller by asking for fewer pages.
>The NFS and vmalloc cases have already been fixed for this.
The NFS and vmalloc cases haven been fixed？
I don’t see if there is any information about that?
Thanks
Qiang
