Hi Andrew,

On Wed, 26 May 2021 17:31:41 -0700 Andrew Morton [off-list ref] wrote:

On Wed, 26 May 2021 20:16:14 -0400 Qian Cai [off-list ref] wrote:

quoted

On 5/26/2021 1:24 PM, Mike Rapoport wrote:  

quoted

On Wed, May 26, 2021 at 12:09:14PM +0000, Qian Cai (QUIC) wrote:  

quoted

quoted

On Tue, May 25, 2021 at 03:25:59PM +0000, Qian Cai (QUIC) wrote:  

quoted

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

Reverted from linux-next for today as well.

-- 
Cheers,
Stephen Rothwell