* [PULL for-6.1 1/3] MAINTAINERS: add Stefano Garzarella as io_uring reviewer
2021-07-29 16:22 [PULL for-6.1 0/3] Block patches Stefan Hajnoczi
@ 2021-07-29 16:22 ` Stefan Hajnoczi
2021-07-29 16:22 ` [PULL for-6.1 2/3] block/io_uring: resubmit when result is -EAGAIN Stefan Hajnoczi
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Stefan Hajnoczi @ 2021-07-29 16:22 UTC (permalink / raw)
To: Peter Maydell, qemu-devel
Cc: Kevin Wolf, qemu-block, Julia Suvorova, Max Reitz,
Stefan Hajnoczi, Aarushi Mehta, Stefano Garzarella
From: Stefano Garzarella <sgarzare@redhat.com>
I've been working with io_uring for a while so I'd like to help
with reviews.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20210728131515.131045-1-sgarzare@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
MAINTAINERS | 1 +
1 file changed, 1 insertion(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 42ac45c3e5..1776d0950b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3257,6 +3257,7 @@ Linux io_uring
M: Aarushi Mehta <mehta.aaru20@gmail.com>
M: Julia Suvorova <jusual@redhat.com>
M: Stefan Hajnoczi <stefanha@redhat.com>
+R: Stefano Garzarella <sgarzare@redhat.com>
L: qemu-block@nongnu.org
S: Maintained
F: block/io_uring.c
--
2.31.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PULL for-6.1 2/3] block/io_uring: resubmit when result is -EAGAIN
2021-07-29 16:22 [PULL for-6.1 0/3] Block patches Stefan Hajnoczi
2021-07-29 16:22 ` [PULL for-6.1 1/3] MAINTAINERS: add Stefano Garzarella as io_uring reviewer Stefan Hajnoczi
@ 2021-07-29 16:22 ` Stefan Hajnoczi
2021-07-29 16:22 ` [PULL for-6.1 3/3] MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver Stefan Hajnoczi
2021-07-30 11:05 ` [PULL for-6.1 0/3] Block patches Peter Maydell
3 siblings, 0 replies; 5+ messages in thread
From: Stefan Hajnoczi @ 2021-07-29 16:22 UTC (permalink / raw)
To: Peter Maydell, qemu-devel
Cc: Kevin Wolf, qemu-block, Stefan Hajnoczi, Julia Suvorova,
Max Reitz, Stefan Hajnoczi, Fabian Ebner, Aarushi Mehta,
Stefano Garzarella
From: Fabian Ebner <f.ebner@proxmox.com>
Linux SCSI can throw spurious -EAGAIN in some corner cases in its
completion path, which will end up being the result in the completed
io_uring request.
Resubmitting such requests should allow block jobs to complete, even
if such spurious errors are encountered.
Co-authored-by: Stefan Hajnoczi <stefanha@gmail.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
Message-id: 20210729091029.65369-1-f.ebner@proxmox.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
block/io_uring.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/block/io_uring.c b/block/io_uring.c
index 00a3ee9fb8..dfa475cc87 100644
--- a/block/io_uring.c
+++ b/block/io_uring.c
@@ -165,7 +165,21 @@ static void luring_process_completions(LuringState *s)
total_bytes = ret + luringcb->total_read;
if (ret < 0) {
- if (ret == -EINTR) {
+ /*
+ * Only writev/readv/fsync requests on regular files or host block
+ * devices are submitted. Therefore -EAGAIN is not expected but it's
+ * known to happen sometimes with Linux SCSI. Submit again and hope
+ * the request completes successfully.
+ *
+ * For more information, see:
+ * https://lore.kernel.org/io-uring/20210727165811.284510-3-axboe@kernel.dk/T/#u
+ *
+ * If the code is changed to submit other types of requests in the
+ * future, then this workaround may need to be extended to deal with
+ * genuine -EAGAIN results that should not be resubmitted
+ * immediately.
+ */
+ if (ret == -EINTR || ret == -EAGAIN) {
luring_resubmit(s, luringcb);
continue;
}
--
2.31.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PULL for-6.1 3/3] MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver
2021-07-29 16:22 [PULL for-6.1 0/3] Block patches Stefan Hajnoczi
2021-07-29 16:22 ` [PULL for-6.1 1/3] MAINTAINERS: add Stefano Garzarella as io_uring reviewer Stefan Hajnoczi
2021-07-29 16:22 ` [PULL for-6.1 2/3] block/io_uring: resubmit when result is -EAGAIN Stefan Hajnoczi
@ 2021-07-29 16:22 ` Stefan Hajnoczi
2021-07-30 11:05 ` [PULL for-6.1 0/3] Block patches Peter Maydell
3 siblings, 0 replies; 5+ messages in thread
From: Stefan Hajnoczi @ 2021-07-29 16:22 UTC (permalink / raw)
To: Peter Maydell, qemu-devel
Cc: Kevin Wolf, qemu-block, Julia Suvorova, Max Reitz,
Stefan Hajnoczi, Philippe Mathieu-Daudé,
Aarushi Mehta, Stefano Garzarella
From: Philippe Mathieu-Daudé <philmd@redhat.com>
I'm interested in following the activity around the NVMe bdrv.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210728183340.2018313-1-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
MAINTAINERS | 1 +
1 file changed, 1 insertion(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1776d0950b..a3d598459a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3178,6 +3178,7 @@ F: block/null.c
NVMe Block Driver
M: Stefan Hajnoczi <stefanha@redhat.com>
R: Fam Zheng <fam@euphon.net>
+R: Philippe Mathieu-Daudé <philmd@redhat.com>
L: qemu-block@nongnu.org
S: Supported
F: block/nvme*
--
2.31.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PULL for-6.1 0/3] Block patches
2021-07-29 16:22 [PULL for-6.1 0/3] Block patches Stefan Hajnoczi
` (2 preceding siblings ...)
2021-07-29 16:22 ` [PULL for-6.1 3/3] MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver Stefan Hajnoczi
@ 2021-07-30 11:05 ` Peter Maydell
3 siblings, 0 replies; 5+ messages in thread
From: Peter Maydell @ 2021-07-30 11:05 UTC (permalink / raw)
To: Stefan Hajnoczi
Cc: Kevin Wolf, Qemu-block, Julia Suvorova, QEMU Developers,
Max Reitz, Aarushi Mehta, Stefano Garzarella
On Thu, 29 Jul 2021 at 17:23, Stefan Hajnoczi <stefanha@redhat.com> wrote:
>
> The following changes since commit 3521ade3510eb5cefb2e27a101667f25dad89935:
>
> Merge remote-tracking branch 'remotes/thuth-gitlab/tags/pull-request-2021-07-29' into staging (2021-07-29 13:17:20 +0100)
>
> are available in the Git repository at:
>
> https://gitlab.com/stefanha/qemu.git tags/block-pull-request
>
> for you to fetch changes up to cc8eecd7f105a1dff5876adeb238a14696061a4a:
>
> MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver (2021-07-29 17:17:34 +0100)
>
> ----------------------------------------------------------------
> Pull request
>
> The main fix here is for io_uring. Spurious -EAGAIN errors can happen and the
> request needs to be resubmitted.
>
> The MAINTAINERS changes carry no risk and we might as well include them in QEMU
> 6.1.
Applied, thanks.
Please update the changelog at https://wiki.qemu.org/ChangeLog/6.1
for any user-visible changes.
-- PMM
^ permalink raw reply [flat|nested] 5+ messages in thread