On 01.02.23 16:27, Stefan Hajnoczi wrote:
When a write request is converted into a write zeroes request by the
detect-zeroes= feature, it is no longer associated with an I/O buffer.
The BDRV_REQ_REGISTERED_BUF flag doesn't make sense without an I/O
buffer and must be cleared because bdrv_co_do_pwrite_zeroes() fails with
-EINVAL when it's set.
Fiona Ebner <[email protected]> bisected and diagnosed this QEMU 7.2
regression where writes containing zeroes to a blockdev with
discard=unmap,detect-zeroes=unmap fail.
Buglink: https://gitlab.com/qemu-project/qemu/-/issues/1404
Fixes: e8b6535533be ("block: add BDRV_REQ_REGISTERED_BUF request flag")
Tested-by: Fiona Ebner <[email protected]>
Cc: [email protected]
Reviewed-by: Eric Blake <[email protected]>
Signed-off-by: Stefan Hajnoczi <[email protected]>
---
block/io.c | 3 +++
1 file changed, 3 insertions(+)
Reviewed-by: Hanna Czenczek <[email protected]>
