@@ -73,12 +73,8 @@ static void luring_resubmit(LuringState *s, LuringAIOCB *luringcb)
/**
* luring_resubmit_short_read:
*
- * Before Linux commit 9d93a3f5a0c ("io_uring: punt short reads to async
- * context") a buffered I/O request with the start of the file range in the
- * page cache could result in a short read. Applications need to resubmit the
- * remaining read request.
- *
- * This is a slow path but recent kernels never take it.
+ * Short reads are rare but may occur. The remaining read request needs to be
+ * resubmitted.
*/
static void luring_resubmit_short_read(LuringState *s, LuringAIOCB *luringcb,
int nread)
Jens Axboe has confirmed that short reads are rare but can happen: https://lore.kernel.org/io-uring/YsU%2FCGkl9ZXUI+Tj@stefanha-x1.localdomain/T/#m729963dc577d709b709c191922e98ec79d7eef54 The luring_resubmit_short_read() comment claimed they were only due to a specific io_uring bug that was fixed in Linux commit 9d93a3f5a0c ("io_uring: punt short reads to async context"), which is wrong. Dominique Martinet found that a btrfs bug also causes short reads. There may be more kernel code paths that result in short reads. Let's consider short reads fair game. Cc: Dominique Martinet <dominique.martinet@atmark-techno.com> Based-on: <20220630010137.2518851-1-dominique.martinet@atmark-techno.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Message-id: 20220706080341.1206476-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> --- block/io_uring.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)