Re: Arm64 crash while reading memory sysfs

From: Andrew Morton
Date: Wed May 26 2021 - 20:31:46 EST


On Wed, 26 May 2021 20:16:14 -0400 Qian Cai <quic_qiancai@xxxxxxxxxxx> wrote:

>
>
> On 5/26/2021 1:24 PM, Mike Rapoport wrote:
> > On Wed, May 26, 2021 at 12:09:14PM +0000, Qian Cai (QUIC) wrote:
> >>>
> >>> On Tue, May 25, 2021 at 03:25:59PM +0000, Qian Cai (QUIC) wrote:
> >>>> Reverting the patchset "arm64: drop pfn_valid_within() and simplify pfn_valid()" [1] from today's linux-next fixed a crash while
> >>> reading files under /sys/devices/system/memory.
> >
> > Does the issue persist of you only revert the latest patch in the series?
> > In next-20210525 it would be commit
> > 89fb47db72f2 ("arm64-drop-pfn_valid_within-and-simplify-pfn_valid-fix")
> > and commit
> > dfe215e9bac2 ("arm64: drop pfn_valid_within() and simplify pfn_valid()").
>
> Reverting those two commits alone is enough to fix the issue.

(cc Stephen)

Thanks, I'll drop

arm64-drop-pfn_valid_within-and-simplify-pfn_valid.patch
arm64-drop-pfn_valid_within-and-simplify-pfn_valid-fix.patch