Message ID | 20170510173945.11819-1-jsnow@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On 05/10/2017 12:39 PM, John Snow wrote: > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1447551 > > If one tries to issue a block_resize while a guest is busy > accessing the disk, it is possible that qemu may deadlock > when invoking aio_poll from both the main loop and the iothread. > > Replace another instance of bdrv_drain_all that doesn't > quite belong. > > Suggested-by: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: John Snow <jsnow@redhat.com> > --- > blockdev.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > Reviewed-by: Eric Blake <eblake@redhat.com> > diff --git a/blockdev.c b/blockdev.c > index 0b38c3d..9ff06f3 100644 > --- a/blockdev.c > +++ b/blockdev.c > @@ -2923,10 +2923,9 @@ void qmp_block_resize(bool has_device, const char *device, > goto out; > } > > - /* complete all in-flight operations before resizing the device */ > - bdrv_drain_all(); > - > + bdrv_drained_begin(bs); > ret = blk_truncate(blk, size, errp); > + bdrv_drained_end(bs); > > out: > blk_unref(blk); >
On 10/05/2017 19:39, John Snow wrote: > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1447551 > > If one tries to issue a block_resize while a guest is busy > accessing the disk, it is possible that qemu may deadlock > when invoking aio_poll from both the main loop and the iothread. > > Replace another instance of bdrv_drain_all that doesn't > quite belong. > > Suggested-by: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: John Snow <jsnow@redhat.com> > --- > blockdev.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/blockdev.c b/blockdev.c > index 0b38c3d..9ff06f3 100644 > --- a/blockdev.c > +++ b/blockdev.c > @@ -2923,10 +2923,9 @@ void qmp_block_resize(bool has_device, const char *device, > goto out; > } > > - /* complete all in-flight operations before resizing the device */ > - bdrv_drain_all(); > - > + bdrv_drained_begin(bs); > ret = blk_truncate(blk, size, errp); > + bdrv_drained_end(bs); > > out: > blk_unref(blk); > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Am 10.05.2017 um 19:39 hat John Snow geschrieben: > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1447551 > > If one tries to issue a block_resize while a guest is busy > accessing the disk, it is possible that qemu may deadlock > when invoking aio_poll from both the main loop and the iothread. > > Replace another instance of bdrv_drain_all that doesn't > quite belong. > > Suggested-by: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: John Snow <jsnow@redhat.com> Thanks, applied to the block branch. Kevin
diff --git a/blockdev.c b/blockdev.c index 0b38c3d..9ff06f3 100644 --- a/blockdev.c +++ b/blockdev.c @@ -2923,10 +2923,9 @@ void qmp_block_resize(bool has_device, const char *device, goto out; } - /* complete all in-flight operations before resizing the device */ - bdrv_drain_all(); - + bdrv_drained_begin(bs); ret = blk_truncate(blk, size, errp); + bdrv_drained_end(bs); out: blk_unref(blk);
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1447551 If one tries to issue a block_resize while a guest is busy accessing the disk, it is possible that qemu may deadlock when invoking aio_poll from both the main loop and the iothread. Replace another instance of bdrv_drain_all that doesn't quite belong. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: John Snow <jsnow@redhat.com> --- blockdev.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)