raspi/linux
1
0
Fork 1
mirror of https://github.com/raspberrypi/linux.git synced 2025-12-06 01:49:46 +00:00
Code Issues Projects Releases Wiki Activity

LoongArch: Let {pte,pmd}_modify() record the status of _PAGE_DIRTY

Browse Source 
commit a073d637c8 upstream.

Now if the PTE/PMD is dirty with _PAGE_DIRTY but without _PAGE_MODIFIED,
after {pte,pmd}_modify() we lose _PAGE_DIRTY, then {pte,pmd}_dirty()
return false and lead to data loss. This can happen in certain scenarios
such as HW PTW doesn't set _PAGE_MODIFIED automatically, so here we need
_PAGE_MODIFIED to record the dirty status (_PAGE_DIRTY).

The new modification involves checking whether the original PTE/PMD has
the _PAGE_DIRTY flag. If it exists, the _PAGE_MODIFIED bit is also set,
ensuring that the {pte,pmd}_dirty() interface can always return accurate
information.

Cc: stable@vger.kernel.org
Co-developed-by: Liupu Wang <wangliupu@loongson.cn>
Signed-off-by: Liupu Wang <wangliupu@loongson.cn>
Signed-off-by: Tianyang Zhang <zhangtianyang@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tianyang Zhang
2025-11-09 16:02:01 +08:00
committed by Greg Kroah-Hartman
parent 5476ceb41c
commit 0c5579294c
1 changed files with 8 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
arch/loongarch/include/asm/pgtable.h
View File

@@ -431,6 +431,9 @@ static inline unsigned long pte_accessible(struct mm_struct *mm, pte_t a)
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
if (pte_val(pte) & _PAGE_DIRTY)
pte_val(pte) |= _PAGE_MODIFIED;
return __pte((pte_val(pte) & _PAGE_CHG_MASK) |
(pgprot_val(newprot) & ~_PAGE_CHG_MASK));
}
@@ -565,9 +568,11 @@ static inline struct page *pmd_page(pmd_t pmd)
static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
{
pmd_val(pmd) = (pmd_val(pmd) & _HPAGE_CHG_MASK) |
(pgprot_val(newprot) & ~_HPAGE_CHG_MASK);
return pmd;
if (pmd_val(pmd) & _PAGE_DIRTY)
pmd_val(pmd) |= _PAGE_MODIFIED;
return __pmd((pmd_val(pmd) & _HPAGE_CHG_MASK) |
(pgprot_val(newprot) & ~_HPAGE_CHG_MASK));
}
static inline pmd_t pmd_mkinvalid(pmd_t pmd)