qemu-kvm/SOURCES/kvm-block-blkio-enable-the-completion-eventfd.patch
2023-11-07 09:43:59 +00:00

55 lines
2.2 KiB
Diff

From ef99db21e9469f3fc946b7bf3edc1837d7b24e0b Mon Sep 17 00:00:00 2001
From: Stefano Garzarella <sgarzare@redhat.com>
Date: Tue, 25 Jul 2023 12:37:44 +0200
Subject: [PATCH 01/14] block/blkio: enable the completion eventfd
RH-Author: Stefano Garzarella <sgarzare@redhat.com>
RH-MergeRequest: 194: block/blkio: backport latest fixes for virtio-blk-* drivers
RH-Bugzilla: 2225354 2225439
RH-Acked-by: Hanna Czenczek <hreitz@redhat.com>
RH-Acked-by: Alberto Faria <None>
RH-Commit: [1/6] d91b3a465942863550130105ae2f38f47a82a360 (sgarzarella/qemu-kvm-c-9-s)
Until libblkio 1.3.0, virtio-blk drivers had completion eventfd
notifications enabled from the start, but from the next releases
this is no longer the case, so we have to explicitly enable them.
In fact, the libblkio documentation says they could be disabled,
so we should always enable them at the start if we want to be
sure to get completion eventfd notifications:
By default, the driver might not generate completion events for
requests so it is necessary to explicitly enable the completion
file descriptor before use:
void blkioq_set_completion_fd_enabled(struct blkioq *q, bool enable);
I discovered this while trying a development version of libblkio:
the guest kernel hangs during boot, while probing the device.
Fixes: fd66dbd424f5 ("blkio: add libblkio block driver")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20230725103744.77343-1-sgarzare@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
(cherry picked from commit 9359c459889fce1804c4e1b2a2ff8f182b4a9ae8)
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
---
block/blkio.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/block/blkio.c b/block/blkio.c
index afcec359f2..3ea9841bd8 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -844,6 +844,7 @@ static int blkio_file_open(BlockDriverState *bs, QDict *options, int flags,
QLIST_INIT(&s->bounce_bufs);
s->blkioq = blkio_get_queue(s->blkio, 0);
s->completion_fd = blkioq_get_completion_fd(s->blkioq);
+ blkioq_set_completion_fd_enabled(s->blkioq, true);
blkio_attach_aio_context(bs, bdrv_get_aio_context(bs));
return 0;
--
2.39.3