Commit df87bdf6 authored by Huacai Chen's avatar Huacai Chen Committed by Hongchen Zhang
Browse files

LoongArch: Set _PAGE_DIRTY only if _PAGE_MODIFIED is set in {pmd,pte}_mkwrite() 

mainline inclusion
from mainline-v6.1-rc7
commit 54e6cd42
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7362E
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/arch/loongarch?id=54e6cd42a183b602e3627ad3aaeeed44f7443e67



--------------------------------

Set _PAGE_DIRTY only if _PAGE_MODIFIED is set in {pmd,pte}_mkwrite().
Otherwise, _PAGE_DIRTY silences the TLB modify exception and make us
have no chance to mark a pmd/pte dirty (_PAGE_MODIFIED) for software.

Reviewed-by: default avatarGuo Ren <guoren@kernel.org>
Signed-off-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
Change-Id: I05f95f28b6c2a18c44b41f253a2f4cbb987521b9
parent 1267d8f9

arch/loongarch/include/asm/pgtable.h

+6 −2
Original line number Diff line number Diff line
@@ -369,7 +369,9 @@ static inline pte_t pte_mkdirty(pte_t pte) 


static inline pte_t pte_mkwrite(pte_t pte)

{

	pte_val(pte) |= (_PAGE_WRITE | _PAGE_DIRTY);

	pte_val(pte) |= _PAGE_WRITE;

	if (pte_val(pte) & _PAGE_MODIFIED)

		pte_val(pte) |= _PAGE_DIRTY;

	return pte;

}
@@ -466,7 +468,9 @@ static inline int pmd_write(pmd_t pmd) 


static inline pmd_t pmd_mkwrite(pmd_t pmd)

{

	pmd_val(pmd) |= (_PAGE_WRITE | _PAGE_DIRTY);

	pmd_val(pmd) |= _PAGE_WRITE;

	if (pmd_val(pmd) & _PAGE_MODIFIED)

		pmd_val(pmd) |= _PAGE_DIRTY;

	return pmd;

}