Re: xfs/folio splat with v6.14-rc1

[Qi Zheng <zhengqi.arch@bytedance.com>]

Hi Zi,

On 2025/2/10 11:35, Zi Yan wrote:
> On 7 Feb 2025, at 17:17, Matthew Wilcox wrote:
> 
>> On Fri, Feb 07, 2025 at 04:29:36PM +0100, Christian Brauner wrote:
>>> while true; do ./xfs.run.sh "generic/437"; done
>>>
>>> allows me to reproduce this fairly quickly.
>>
>> on holiday, back monday
> 
> git bisect points to commit
> 4817f70c25b6 ("x86: select ARCH_SUPPORTS_PT_RECLAIM if X86_64").
> Qi is cc'd.
> 
> After deselect PT_RECLAIM on v6.14-rc1, the issue is gone.
> At least, no splat after running for more than 300s,
> whereas the splat is usually triggered after ~20s with
> PT_RECLAIM set.

The PT_RECLAIM mainly made the following two changes:

1) try to reclaim page table pages during madvise(MADV_DONTNEED)
2) Unconditionally select MMU_GATHER_RCU_TABLE_FREE

Will ./xfs.run.sh "generic/437" perform the madvise(MADV_DONTNEED)?

Anyway, I will try to reproduce it locally and troubleshoot it.

Thanks!

> 
> --
> Best Regards,
> Yan, Zi