The correct folio replacement for "set_page_dirty()" is
"folio_mark_dirty()", not "folio_set_dirty()". Using the latter won't
properly inform the FS using the dirty_folio() callback.
This has been found by code inspection, but likely this can result in
some real trouble when zapping dirty PTEs that point at clean pagecache
folios.
Reported-by: Ryan Roberts <[email protected]>
Closes: https://lkml.kernel.org/r/[email protected]
Fixes: c46265030b0f ("mm/memory: page_remove_rmap() -> folio_remove_rmap_pte()")
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Andrew Morton <[email protected]>
Signed-off-by: David Hildenbrand <[email protected]>
---
mm/memory.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/memory.c b/mm/memory.c
index 7e1f4849463aa..89bcae0b224d6 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1464,7 +1464,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
delay_rmap = 0;
if (!folio_test_anon(folio)) {
if (pte_dirty(ptent)) {
- folio_set_dirty(folio);
+ folio_mark_dirty(folio);
if (tlb_delay_rmap(tlb)) {
delay_rmap = 1;
force_flush = 1;
--
2.43.0
On 22/01/2024 17:17, David Hildenbrand wrote:
> The correct folio replacement for "set_page_dirty()" is
> "folio_mark_dirty()", not "folio_set_dirty()". Using the latter won't
> properly inform the FS using the dirty_folio() callback.
That set_page_dirty() naming is pretty nasty, hey.
>
> This has been found by code inspection, but likely this can result in
> some real trouble when zapping dirty PTEs that point at clean pagecache
> folios.
>
> Reported-by: Ryan Roberts <[email protected]>
> Closes: https://lkml.kernel.org/r/[email protected]
> Fixes: c46265030b0f ("mm/memory: page_remove_rmap() -> folio_remove_rmap_pte()")
> Cc: Matthew Wilcox (Oracle) <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Signed-off-by: David Hildenbrand <[email protected]>
Reviewed-by: Ryan Roberts <[email protected]>
> ---
> mm/memory.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index 7e1f4849463aa..89bcae0b224d6 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -1464,7 +1464,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
> delay_rmap = 0;
> if (!folio_test_anon(folio)) {
> if (pte_dirty(ptent)) {
> - folio_set_dirty(folio);
> + folio_mark_dirty(folio);
> if (tlb_delay_rmap(tlb)) {
> delay_rmap = 1;
> force_flush = 1;
Reviewed-by: Yuezhang Mo <[email protected]>
Without this fix, testing the latest exfat with xfstests, test cases generic/029
and generic/030 will fail.
> -----Original Message-----
> From: [email protected] <[email protected]> On Behalf
> Of David Hildenbrand
> Sent: Tuesday, January 23, 2024 1:18 AM
> To: [email protected]
> Cc: [email protected]; David Hildenbrand <[email protected]>; Ryan
> Roberts <[email protected]>; Matthew Wilcox <[email protected]>;
> Andrew Morton <[email protected]>
> Subject: [PATCH v1] mm/memory: fix folio_set_dirty() vs. folio_mark_dirty() in
> zap_pte_range()
>
> The correct folio replacement for "set_page_dirty()" is
> "folio_mark_dirty()", not "folio_set_dirty()". Using the latter won't
> properly inform the FS using the dirty_folio() callback.
>
> This has been found by code inspection, but likely this can result in
> some real trouble when zapping dirty PTEs that point at clean pagecache
> folios.
>
> Reported-by: Ryan Roberts <[email protected]>
> Closes:
> https://lkml.kernel.org/r/[email protected]
> Fixes: c46265030b0f ("mm/memory: page_remove_rmap() ->
> folio_remove_rmap_pte()")
> Cc: Matthew Wilcox (Oracle) <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Signed-off-by: David Hildenbrand <[email protected]>
> Reviewed-by: Ryan Roberts <[email protected]>
> ---
> mm/memory.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index 7e1f4849463aa..89bcae0b224d6 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -1464,7 +1464,7 @@ static unsigned long zap_pte_range(struct
> mmu_gather *tlb,
> delay_rmap = 0;
> if (!folio_test_anon(folio)) {
> if (pte_dirty(ptent)) {
> - folio_set_dirty(folio);
> + folio_mark_dirty(folio);
> if (tlb_delay_rmap(tlb)) {
> delay_rmap = 1;
> force_flush = 1;
On 23.01.24 09:49, [email protected] wrote:
> Reviewed-by: Yuezhang Mo <[email protected]>
>
> Without this fix, testing the latest exfat with xfstests, test cases generic/029
> and generic/030 will fail.
Great, thanks for testing and for providing actual reproducers!
--
Cheers,
David / dhildenb