On 11/13/23 10:27, Tom Yan wrote:
So I realized that I mixed up the queue write_cache and the sd
cache_type sysfs files. cache_type is working fine.
But then I noticed that in commit
43c9835b144c7ce29efe142d662529662a9eb376, you define QUEUE_FLAG_HW_WC
as 18, which is also the value of QUEUE_FLAG_FUA. Was it intentional?
If so, what's the reason behind it?
Does the untested patch below help?
Thanks,
Bart.
[PATCH] block: Make sure that all queue flags have a different value
Queue flags QUEUE_FLAG_HW_WC has the same numerical value as
QUEUE_FLAG_FUA. Fix this by changing the QUEUE_FLAG_HW_WC definition.
Cc: Christoph Hellwig <hch@xxxxxx>
Reported-by: Tom Yan <tom.ty89@xxxxxxxxx>
Fixes: 43c9835b144c ("block: don't allow enabling a cache on devices that don't support it")
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
include/linux/blkdev.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index eef450f25982..f59fcd5b499a 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -538,7 +538,7 @@ struct request_queue {
#define QUEUE_FLAG_ADD_RANDOM 10 /* Contributes to random pool */
#define QUEUE_FLAG_SYNCHRONOUS 11 /* always completes in submit context */
#define QUEUE_FLAG_SAME_FORCE 12 /* force complete on same CPU */
-#define QUEUE_FLAG_HW_WC 18 /* Write back caching supported */
+#define QUEUE_FLAG_HW_WC 13 /* Write back caching supported */
#define QUEUE_FLAG_INIT_DONE 14 /* queue is initialized */
#define QUEUE_FLAG_STABLE_WRITES 15 /* don't modify blks until WB is done */
#define QUEUE_FLAG_POLL 16 /* IO polling enabled if set */
