Re: [PATCH 04/47] LoongArch: Set _PAGE_DIRTY only if _PAGE_WRITE is set in {pmd,pte}_mkdirty()

[Xi Ruoyao]

On Thu, 2022-11-17 at 21:59 +0800, Xi Ruoyao wrote:
> Hi Huacai,
> 
> On Thu, 2022-11-17 at 12:25 +0800, Huacai Chen wrote:
> > Now {pmd,pte}_mkdirty() set _PAGE_DIRTY bit unconditionally, this causes
> > random segmentation fault after commit 0ccf7f168e17bb7e ("mm/thp: carry
> > over dirty bit when thp splits on pmd").
> 
> Hmm, the pte_mkdirty call is already removed in commit 624a2c94f5b7a081
> ("Partly revert \"mm/thp: carry over dirty bit when thp splits on
> pmd\"").
> 
> Not sure if this issue is related to some random segfaults I've observed
> recently though.  My last kernel build contains 0ccf7f168e17bb7e but
> does not contain 624a2c94f5b7a081.

I can confirm this patch alone (without 624a2c94f5b7a081) fixes the
random segfaults I've recently encountered running GCC testsuite.

Link: https://gcc.gnu.org/pipermail/gcc/2022-November/239857.html
Tested-by: Xi Ruoyao <xry111@xxxxxxxxxxx>

-- 
Xi Ruoyao <xry111@xxxxxxxxxxx>
School of Aerospace Science and Technology, Xidian University