[PULL,01/11] io_uring: retry io_uring_submit() if it fails with errno=EINTR

Commit Message

Stefan Hajnoczi June 5, 2020, 9:47 a.m. UTC

From: Stefano Garzarella <[e-mail]>

As recently documented [1], io_uring_enter(2) syscall can return an
error (errno=EINTR) if the operation was interrupted by a delivery
of a signal before it could complete.

This should happen when IORING_ENTER_GETEVENTS flag is used, for
example during io_uring_submit_and_wait() or during io_uring_submit()
when IORING_SETUP_IOPOLL is enabled.

We shouldn't have this problem for now, but it's better to prevent it.

[1] https://github.com/axboe/liburing/commit/344355ec6619de8f4e64584c9736530b5346e4f4

Signed-off-by: Stefano Garzarella <[e-mail]>
Message-id: [e-mail]
Signed-off-by: Stefan Hajnoczi <[e-mail]>
---
 block/io_uring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/block/io_uring.c b/block/io_uring.c
index a3142ca989..9765681f7c 100644
--- a/block/io_uring.c
+++ b/block/io_uring.c
@@ -231,7 +231,7 @@  static int ioq_submit(LuringState *s)
         trace_luring_io_uring_submit(s, ret);
         /* Prevent infinite loop if submission is refused */
         if (ret <= 0) {
-            if (ret == -EAGAIN) {
+            if (ret == -EAGAIN || ret == -EINTR) {
                 continue;
             }
             break;