The following changes since commit 560009f2c8b57b7cdd31a5693ea86ab369382f49:

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging (2019-10-07 15:40:53 +0100)

https://github.com/stefanha/qemu.git tags/block-pull-request

for you to fetch changes up to 4d804b5305ffb4d5fa414c38d4f1bdfb987c8d0b:

iotests/262: Switch source/dest VM launch order (2019-10-08 14:28:25 +0100)

This pull request also contains the two commits from the previous pull request

that was dropped due to a mingw compilation error. The compilation should now

be fixed.

Max Reitz (2):

block: Skip COR for inactive nodes

iotests/262: Switch source/dest VM launch order

Sergio Lopez (1):

virtio-blk: schedule virtio_notify_config to run on main context

Vladimir Sementsov-Ogievskiy (1):

util/ioc.c: try to reassure Coverity about qemu_iovec_init_extended

block/io.c | 41 +++++++++++++++++++++++++-------------

hw/block/virtio-blk.c | 16 ++++++++++++++-

util/iov.c | 5 +++--

tests/qemu-iotests/262 | 12 +++++------

tests/qemu-iotests/262.out | 6 +++---

5 files changed, 54 insertions(+), 26 deletions(-)

2.21.0

From: Max Reitz <mreitz@redhat.com>

Launching the destination VM before the source VM gives us a regression

test for HEAD^:

The guest device causes a read from the disk image through

guess_disk_lchs(). This will not work if the first sector (containing

the partition table) is yet unallocated, we use COR, and the node is

inactive.

tests/qemu-iotests/262 | 12 ++++++------

tests/qemu-iotests/262.out | 6 +++---

2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/tests/qemu-iotests/262 b/tests/qemu-iotests/262

index XXXXXXX..XXXXXXX 100755

--- a/tests/qemu-iotests/262

+++ b/tests/qemu-iotests/262

@@ -XXX,XX +XXX,XX @@ with iotests.FilePath('img') as img_path, \

os.mkfifo(fifo)

- iotests.log('Launching source VM...')

- add_opts(vm_a)

- vm_a.launch()

-

- vm_a.enable_migration_events('A')

-

iotests.log('Launching destination VM...')

add_opts(vm_b)

vm_b.add_incoming("exec: cat '%s'" % (fifo))

@@ -XXX,XX +XXX,XX @@ with iotests.FilePath('img') as img_path, \

vm_b.enable_migration_events('B')

+ iotests.log('Launching source VM...')

+ add_opts(vm_a)

+ vm_a.launch()

+ vm_a.enable_migration_events('A')

iotests.log('Starting migration to B...')

iotests.log(vm_a.qmp('migrate', uri='exec:cat >%s' % (fifo)))

with iotests.Timeout(3, 'Migration does not complete'):

diff --git a/tests/qemu-iotests/262.out b/tests/qemu-iotests/262.out

index XXXXXXX..XXXXXXX 100644

--- a/tests/qemu-iotests/262.out

+++ b/tests/qemu-iotests/262.out

@@ -XXX,XX +XXX,XX @@

-Launching source VM...

-Enabling migration QMP events on A...

-{"return": {}}

Launching destination VM...

Enabling migration QMP events on B...

{"return": {}}

+Launching source VM...

+Enabling migration QMP events on A...

+{"return": {}}

Starting migration to B...

{"return": {}}

{"data": {"status": "setup"}, "event": "MIGRATION", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}

2.21.0

From: Max Reitz <mreitz@redhat.com>

We must not write data to inactive nodes, and a COR is certainly

something we can simply not do without upsetting anyone. So skip COR

operations on inactive nodes.

Signed-off-by: Max Reitz <mreitz@redhat.com>

Reviewed-by: Eric Blake <eblake@redhat.com>

Message-id: 20191001174827.11081-2-mreitz@redhat.com

Message-Id: <20191001174827.11081-2-mreitz@redhat.com>

block/io.c | 41 +++++++++++++++++++++++++++--------------

1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/block/io.c b/block/io.c

--- a/block/io.c

+++ b/block/io.c

@@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,

int max_transfer = MIN_NON_ZERO(bs->bl.max_transfer,

BDRV_REQUEST_MAX_BYTES);

unsigned int progress = 0;

+ bool skip_write;

if (!drv) {

return -ENOMEDIUM;

}

+ /*

+ * Do not write anything when the BDS is inactive. That is not

+ * allowed, and it would not help.

+ */

+ skip_write = (bs->open_flags & BDRV_O_INACTIVE);

+

/* FIXME We cannot require callers to have write permissions when all they

* are doing is a read request. If we did things right, write permissions

* would be obtained anyway, but internally by the copy-on-read code. As

@@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,

while (cluster_bytes) {

int64_t pnum;

- ret = bdrv_is_allocated(bs, cluster_offset,

- MIN(cluster_bytes, max_transfer), &pnum);

- if (ret < 0) {

- /* Safe to treat errors in querying allocation as if

- * unallocated; we'll probably fail again soon on the

- * read, but at least that will set a decent errno.

- */

+ if (skip_write) {

+ ret = 1; /* "already allocated", so nothing will be copied */

pnum = MIN(cluster_bytes, max_transfer);

- }

+ } else {

+ ret = bdrv_is_allocated(bs, cluster_offset,

+ MIN(cluster_bytes, max_transfer), &pnum);

+ if (ret < 0) {

+ /*

+ * Safe to treat errors in querying allocation as if

+ * unallocated; we'll probably fail again soon on the

+ * read, but at least that will set a decent errno.

+ */

+ pnum = MIN(cluster_bytes, max_transfer);

+ }

- /* Stop at EOF if the image ends in the middle of the cluster */

- if (ret == 0 && pnum == 0) {

- assert(progress >= bytes);

- break;

- }

+ /* Stop at EOF if the image ends in the middle of the cluster */

+ if (ret == 0 && pnum == 0) {

+ assert(progress >= bytes);

+ break;

+ }

- assert(skip_bytes < pnum);

+ assert(skip_bytes < pnum);

+ }

if (ret <= 0) {

QEMUIOVector local_qiov;

2.21.0

From: Sergio Lopez <slp@redhat.com>

virtio_notify_config() needs to acquire the global mutex, which isn't

allowed from an iothread, and may lead to a deadlock like this:

- main thead

* Has acquired: qemu_global_mutex.

* Is trying the acquire: iothread AioContext lock via

AIO_WAIT_WHILE (after aio_poll).

- iothread

* Has acquired: AioContext lock.

* Is trying to acquire: qemu_global_mutex (via

virtio_notify_config->prepare_mmio_access).

If virtio_blk_resize() is called from an iothread, schedule

virtio_notify_config() to be run in the main context BH.

[Removed unnecessary newline as suggested by Kevin Wolf

<kwolf@redhat.com>.

hw/block/virtio-blk.c | 16 +++++++++++++++-

1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c

--- a/hw/block/virtio-blk.c

+++ b/hw/block/virtio-blk.c

@@ -XXX,XX +XXX,XX @@

#include "qemu/iov.h"

#include "qemu/module.h"

#include "qemu/error-report.h"

+#include "qemu/main-loop.h"

#include "trace.h"

#include "hw/block/block.h"

#include "hw/qdev-properties.h"

@@ -XXX,XX +XXX,XX @@ static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,

return 0;

2.21.0