Series comparison

-[Qemu-devel] [PULL 0/1] Block patches
+[PULL for-6.1 0/3] Block patches
-The following changes since commit 0b5e750bea635b167eb03d86c3d9a09bbd43bc06:
+The following changes since commit 3521ade3510eb5cefb2e27a101667f25dad89935:
-  Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging (2019-02-12 10:53:37 +0000)
+  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:
-  git://github.com/stefanha/qemu.git tags/block-pull-request
+  https://gitlab.com/stefanha/qemu.git tags/block-pull-request
-for you to fetch changes up to 42824b4d16da56a50ff4027f6cd22378e0e2666e:
+for you to fetch changes up to cc8eecd7f105a1dff5876adeb238a14696061a4a:
-  virtio-blk: set correct config size for the host driver (2019-02-13 16:18:17 +0800)
+  MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver (2021-07-29 17:17:34 +0100)
 ----------------------------------------------------------------
 Pull request
-Fix a virtio-blk migration regression.
+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
 .1.
 ----------------------------------------------------------------
-Changpeng Liu (1):
+Fabian Ebner (1):
-  virtio-blk: set correct config size for the host driver
+  block/io_uring: resubmit when result is -EAGAIN
- hw/block/virtio-blk.c | 13 +++++++++----
+Philippe Mathieu-Daudé (1):
-file changed, 9 insertions(+), 4 deletions(-)
+  MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver
 Stefano Garzarella (1):
   MAINTAINERS: add Stefano Garzarella as io_uring reviewer
  MAINTAINERS      |  2 ++
  block/io_uring.c | 16 +++++++++++++++-
 files changed, 17 insertions(+), 1 deletion(-)
 --
-.20.1
+.31.1

-New patch
+[PULL for-6.1 1/3] MAINTAINERS: add Stefano Garzarella as io_uring reviewer
+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 +
+file changed, 1 insertion(+)
+diff --git a/MAINTAINERS b/MAINTAINERS
+index XXXXXXX..XXXXXXX 100644
+--- a/MAINTAINERS
++++ b/MAINTAINERS
+@@ -XXX,XX +XXX,XX @@ 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
+--
+.31.1

-New patch
+[PULL for-6.1 2/3] block/io_uring: resubmit when result is -EAGAIN
+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 +++++++++++++++-
+file changed, 15 insertions(+), 1 deletion(-)
+diff --git a/block/io_uring.c b/block/io_uring.c
+index XXXXXXX..XXXXXXX 100644
+--- a/block/io_uring.c
++++ b/block/io_uring.c
+@@ -XXX,XX +XXX,XX @@ 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;
+             }
+--
+.31.1

-[Qemu-devel] [PULL 1/1] virtio-blk: set correct config size for the host driver
+[PULL for-6.1 3/3] MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver
-From: Changpeng Liu <changpeng.liu@intel.com>
+From: Philippe Mathieu-Daudé <philmd@redhat.com>
-Commit caa1ee43 "vhost-user-blk: add discard/write zeroes features
+I'm interested in following the activity around the NVMe bdrv.
 support" added fields to struct virtio_blk_config. This changes
 the size of the config space and breaks migration from QEMU 3.1
 and older:
-qemu-system-ppc64: get_pci_config_device: Bad config data: i=0x10 read: 41 device: 1 cmask: ff wmask: 80 w1cmask:0
+Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
-qemu-system-ppc64: Failed to load PCIDevice:config
+Message-id: 20210728183340.2018313-1-philmd@redhat.com
 qemu-system-ppc64: Failed to load virtio-blk:virtio
 qemu-system-ppc64: error while loading state for instance 0x0 of device 'pci@800000020000000:01.0/virtio-blk'
 qemu-system-ppc64: load of migration failed: Invalid argument
 Since virtio-blk doesn't support the "discard" and "write zeroes"
 features, it shouldn't even expose the associated fields in the
 config space actually. Just include all fields up to num_queues to
 match QEMU 3.1 and older.
 Signed-off-by: Changpeng Liu <changpeng.liu@intel.com>
 Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
 Message-id: 1550022537-27565-1-git-send-email-changpeng.liu@intel.com
 Message-Id: <1550022537-27565-1-git-send-email-changpeng.liu@intel.com>
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
- hw/block/virtio-blk.c | 13 +++++++++----
+ MAINTAINERS | 1 +
-file changed, 9 insertions(+), 4 deletions(-)
+file changed, 1 insertion(+)
-diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
+diff --git a/MAINTAINERS b/MAINTAINERS
 index XXXXXXX..XXXXXXX 100644
---- a/hw/block/virtio-blk.c
+--- a/MAINTAINERS
-+++ b/hw/block/virtio-blk.c
++++ b/MAINTAINERS
-@@ -XXX,XX +XXX,XX @@
+@@ -XXX,XX +XXX,XX @@ F: block/null.c
- #include "hw/virtio/virtio-bus.h"
+ NVMe Block Driver
- #include "hw/virtio/virtio-access.h"
+ M: Stefan Hajnoczi <stefanha@redhat.com>
+ R: Fam Zheng <fam@euphon.net>
-+/* We don't support discard yet, hide associated config fields. */
++R: Philippe Mathieu-Daudé <philmd@redhat.com>
-+#define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \
+ L: qemu-block@nongnu.org
-+                                     max_discard_sectors)
+ S: Supported
-+
+ F: block/nvme*
  static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq,
                                      VirtIOBlockReq *req)
  {
@@ -XXX,XX +XXX,XX @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
      blkcfg.alignment_offset = 0;
      blkcfg.wce = blk_enable_write_cache(s->blk);
      virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues);
 -    memcpy(config, &blkcfg, sizeof(struct virtio_blk_config));
 +    memcpy(config, &blkcfg, VIRTIO_BLK_CFG_SIZE);
 +    QEMU_BUILD_BUG_ON(VIRTIO_BLK_CFG_SIZE > sizeof(blkcfg));
  }
  static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
@@ -XXX,XX +XXX,XX @@ static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
      VirtIOBlock *s = VIRTIO_BLK(vdev);
      struct virtio_blk_config blkcfg;
 -    memcpy(&blkcfg, config, sizeof(blkcfg));
 +    memcpy(&blkcfg, config, VIRTIO_BLK_CFG_SIZE);
 +    QEMU_BUILD_BUG_ON(VIRTIO_BLK_CFG_SIZE > sizeof(blkcfg));
      aio_context_acquire(blk_get_aio_context(s->blk));
      blk_set_enable_write_cache(s->blk, blkcfg.wce != 0);
@@ -XXX,XX +XXX,XX @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
          return;
      }
 -    virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK,
 -                sizeof(struct virtio_blk_config));
 +    virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, VIRTIO_BLK_CFG_SIZE);
      s->blk = conf->conf.blk;
      s->rq = NULL;
 --
-.20.1
+.31.1

From: Changpeng Liu <changpeng.liu@intel.com>

Commit caa1ee43 "vhost-user-blk: add discard/write zeroes features
support" added fields to struct virtio_blk_config. This changes
the size of the config space and breaks migration from QEMU 3.1
and older:

qemu-system-ppc64: get_pci_config_device: Bad config data: i=0x10 read: 41 device: 1 cmask: ff wmask: 80 w1cmask:0
qemu-system-ppc64: Failed to load PCIDevice:config
qemu-system-ppc64: Failed to load virtio-blk:virtio
qemu-system-ppc64: error while loading state for instance 0x0 of device 'pci@800000020000000:01.0/virtio-blk'
qemu-system-ppc64: load of migration failed: Invalid argument

Since virtio-blk doesn't support the "discard" and "write zeroes"
features, it shouldn't even expose the associated fields in the
config space actually. Just include all fields up to num_queues to
match QEMU 3.1 and older.

Signed-off-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 1550022537-27565-1-git-send-email-changpeng.liu@intel.com
Message-Id: <1550022537-27565-1-git-send-email-changpeng.liu@intel.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hw/block/virtio-blk.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index XXXXXXX..XXXXXXX 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -XXX,XX +XXX,XX @@
 #include "hw/virtio/virtio-bus.h"
 #include "hw/virtio/virtio-access.h"
 
+/* We don't support discard yet, hide associated config fields. */
+#define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \
+                                     max_discard_sectors)
+
 static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq,
                                     VirtIOBlockReq *req)
 {
@@ -XXX,XX +XXX,XX @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
     blkcfg.alignment_offset = 0;
     blkcfg.wce = blk_enable_write_cache(s->blk);
     virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues);
-    memcpy(config, &blkcfg, sizeof(struct virtio_blk_config));
+    memcpy(config, &blkcfg, VIRTIO_BLK_CFG_SIZE);
+    QEMU_BUILD_BUG_ON(VIRTIO_BLK_CFG_SIZE > sizeof(blkcfg));
 }
 
 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
@@ -XXX,XX +XXX,XX @@ static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
     VirtIOBlock *s = VIRTIO_BLK(vdev);
     struct virtio_blk_config blkcfg;
 
-    memcpy(&blkcfg, config, sizeof(blkcfg));
+    memcpy(&blkcfg, config, VIRTIO_BLK_CFG_SIZE);
+    QEMU_BUILD_BUG_ON(VIRTIO_BLK_CFG_SIZE > sizeof(blkcfg));
 
     aio_context_acquire(blk_get_aio_context(s->blk));
     blk_set_enable_write_cache(s->blk, blkcfg.wce != 0);
@@ -XXX,XX +XXX,XX @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
         return;
     }
 
-    virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK,
-                sizeof(struct virtio_blk_config));
+    virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, VIRTIO_BLK_CFG_SIZE);
 
     s->blk = conf->conf.blk;
     s->rq = NULL;
-- 
2.20.1

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.

----------------------------------------------------------------

Fabian Ebner (1):
  block/io_uring: resubmit when result is -EAGAIN

Philippe Mathieu-Daudé (1):
  MAINTAINERS: Added myself as a reviewer for the NVMe Block Driver

Stefano Garzarella (1):
  MAINTAINERS: add Stefano Garzarella as io_uring reviewer

MAINTAINERS      |  2 ++
 block/io_uring.c | 16 +++++++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

-- 
2.31.1

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 XXXXXXX..XXXXXXX 100644
--- a/block/io_uring.c
+++ b/block/io_uring.c
@@ -XXX,XX +XXX,XX @@ 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