Re: [Qemu-devel] [PATCH v5] blockdev: acquire aio_context for bitmap add/remove

[John Snow <jsnow@redhat.com>]

On 2/19/19 9:59 AM, Eric Blake wrote:
> On 2/18/19 5:31 PM, John Snow wrote:
>> When bitmaps are persistent, they may incur a disk read or write when bitmaps
>> are added or removed. For configurations like virtio-dataplane, failing to
>> acquire this lock will abort QEMU when disk IO occurs.
>>
>> We used to acquire aio_context as part of the bitmap lookup, so re-introduce
>> the lock for just the cases that have an IO penalty. Commit 2119882c removed
>> these locks, and I failed to notice this when we committed fd5ae4cc, so this
>> has been broken since persistent bitmaps were introduced.
>>
>> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1672010
>> Reported-By: Aihua Liang <aliang@redhat.com>
>> Signed-off-by: John Snow <jsnow@redhat.com>
>> ---
>> v5: I'm having a really bad day. This version actually has the semicolon.
>> ---
>>  blockdev.c | 26 ++++++++++++++++++++------
>>  1 file changed, 20 insertions(+), 6 deletions(-)
> 
> Reviewed-by: Eric Blake <eblake@redhat.com>
> 
> and yes, this time it builds.
> 

I am really very sorry for the noise on this simple series. Thank you
for the review and your patience.

--John