Re: [Qemu-devel] [PATCH v6] qcow2: Buffer L1 table in snapshot refcount update

[Max Reitz <mreitz@redhat.com>]

On 2014-11-20 at 15:32, Max Reitz wrote:
> On 2014-11-11 at 16:27, Max Reitz wrote:
>> From: Zhang Haoyu <zhanghy@sangfor.com>
>>
>> Buffer the active L1 table in qcow2_update_snapshot_refcount() in order
>> to prevent in-place conversion of the L1 table buffer in the
>> BDRVQcowState to big endian and back, which would lead to data
>> corruption if that buffer was accessed concurrently. This should not
>> happen but better being safe than sorry.
>>
>> Signed-off-by: Zhang Haoyu <zhanghy@sangfor.com>
>> Signed-off-by: Max Reitz <mreitz@redhat.com>
>> ---
>> v6 for "snapshot: use local variable to bdrv_pwrite_sync L1 table" (I
>> changed the commit message wording to make it more clear what this patch
>> does and why we want it).
>>
>> Changes in v6:
>> - Only copy the local buffer back into s->l1_table if we are indeed
>>    accessing the local L1 table
>> - Use qemu_vfree() instead of g_free()
>> ---
>>   block/qcow2-refcount.c | 30 ++++++++++++++----------------
>>   1 file changed, 14 insertions(+), 16 deletions(-)
>
> Ping

-(Png)²

(got it? because i² = -1, ha-ha-haa)