6.15-stable review patch. If anyone has any objections, please let me know.
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From: John Garry john.g.garry@oracle.com
[ Upstream commit 1de67e8e28fc47d71ee06ffa0185da549b378ffb ]
Currently we just ensure that a non-zero value in chunk_sectors aligns with any atomic write boundary, as the blk boundary functionality uses both these values.
However it is also improper to have atomic write unit max > chunk_sectors (for non-zero chunk_sectors), as this would lead to splitting of atomic write bios (which is disallowed).
Sanitize atomic write unit max against chunk_sectors to avoid any potential problems.
Fixes: d00eea91deaf3 ("block: Add extra checks in blk_validate_atomic_write_limits()") Reviewed-by: Nilay Shroff nilay@linux.ibm.com Signed-off-by: John Garry john.g.garry@oracle.com Reviewed-by: Martin K. Petersen martin.petersen@oracle.com Link: https://lore.kernel.org/r/20250711105258.3135198-3-john.g.garry@oracle.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-settings.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/block/blk-settings.c b/block/blk-settings.c index 4817e7ca03f8..d8c79e5112b4 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -186,6 +186,8 @@ static void blk_atomic_writes_update_limits(struct queue_limits *lim) static void blk_validate_atomic_write_limits(struct queue_limits *lim) { unsigned int boundary_sectors; + unsigned int atomic_write_hw_max_sectors = + lim->atomic_write_hw_max >> SECTOR_SHIFT;
if (!(lim->features & BLK_FEAT_ATOMIC_WRITES)) goto unsupported; @@ -207,6 +209,10 @@ static void blk_validate_atomic_write_limits(struct queue_limits *lim) lim->atomic_write_hw_max)) goto unsupported;
+ if (WARN_ON_ONCE(lim->chunk_sectors && + atomic_write_hw_max_sectors > lim->chunk_sectors)) + goto unsupported; + boundary_sectors = lim->atomic_write_hw_boundary >> SECTOR_SHIFT;
if (boundary_sectors) {