diff mbox series

[v3,33/46] kmsan: block: skip bio block merging logic for KMSAN

Message ID 20220426164315.625149-34-glider@google.com (mailing list archive)
State New
Headers show
Series Add KernelMemorySanitizer infrastructure | expand

Commit Message

Alexander Potapenko April 26, 2022, 4:43 p.m. UTC 
KMSAN doesn't allow treating adjacent memory pages as such, if they were
allocated by different alloc_pages() calls.
The block layer however does so: adjacent pages end up being used
together. To prevent this, make page_is_mergeable() return false under
KMSAN.

Suggested-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>

---

Link: https://linux-review.googlesource.com/id/Ie29cc2464c70032347c32ab2a22e1e7a0b37b905
---
 block/bio.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/block/bio.c b/block/bio.c
index 4259125e16ab2..db56090c00bae 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -836,6 +836,8 @@  static inline bool page_is_mergeable(const struct bio_vec *bv,
 		return false;
 
 	*same_page = ((vec_end_addr & PAGE_MASK) == page_addr);
+	if (!*same_page && IS_ENABLED(CONFIG_KMSAN))
+		return false;
 	if (*same_page)
 		return true;
 	return (bv->bv_page + bv_end / PAGE_SIZE) == (page + off / PAGE_SIZE);