blockdev.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
If the bitmap can't be used for whatever reason, we skip putting down
the reference. Fix that.
In practice, this means that if you attempt to gracefully exit QEMU
after a backup command being rejected, bdrv_close_all will fail and
tell you some unpleasant things via assert().
Reported-by: aihua liang <aliang@redhat.com>
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1703916
Signed-off-by: John Snow <jsnow@redhat.com>
---
blockdev.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/blockdev.c b/blockdev.c
index 79fbac8450..278ecdd122 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3525,8 +3525,7 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
if (set_backing_hd) {
bdrv_set_backing_hd(target_bs, source, &local_err);
if (local_err) {
- bdrv_unref(target_bs);
- goto out;
+ goto unref;
}
}
@@ -3534,11 +3533,10 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
if (!bmap) {
error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
- bdrv_unref(target_bs);
- goto out;
+ goto unref;
}
if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_DEFAULT, errp)) {
- goto out;
+ goto unref;
}
}
if (!backup->auto_finalize) {
@@ -3552,12 +3550,12 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
backup->sync, bmap, backup->compress,
backup->on_source_error, backup->on_target_error,
job_flags, NULL, NULL, txn, &local_err);
- bdrv_unref(target_bs);
if (local_err != NULL) {
error_propagate(errp, local_err);
- goto out;
}
+unref:
+ bdrv_unref(target_bs);
out:
aio_context_release(aio_context);
return job;
--
2.20.1
Am 10.05.2019 um 23:52 hat John Snow geschrieben:
> If the bitmap can't be used for whatever reason, we skip putting down
> the reference. Fix that.
>
> In practice, this means that if you attempt to gracefully exit QEMU
> after a backup command being rejected, bdrv_close_all will fail and
> tell you some unpleasant things via assert().
>
> Reported-by: aihua liang <aliang@redhat.com>
> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1703916
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
> blockdev.c | 12 +++++-------
> 1 file changed, 5 insertions(+), 7 deletions(-)
>
> diff --git a/blockdev.c b/blockdev.c
> index 79fbac8450..278ecdd122 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -3525,8 +3525,7 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
> if (set_backing_hd) {
> bdrv_set_backing_hd(target_bs, source, &local_err);
> if (local_err) {
> - bdrv_unref(target_bs);
> - goto out;
> + goto unref;
> }
> }
>
> @@ -3534,11 +3533,10 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
> bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
> if (!bmap) {
> error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
> - bdrv_unref(target_bs);
> - goto out;
> + goto unref;
> }
> if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_DEFAULT, errp)) {
> - goto out;
> + goto unref;
> }
> }
> if (!backup->auto_finalize) {
> @@ -3552,12 +3550,12 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
> backup->sync, bmap, backup->compress,
> backup->on_source_error, backup->on_target_error,
> job_flags, NULL, NULL, txn, &local_err);
> - bdrv_unref(target_bs);
> if (local_err != NULL) {
> error_propagate(errp, local_err);
> - goto out;
Please leave a 'goto unref' here so we can later add more code without
modifying unrelated error paths (or, more likely, forgetting to modify
them).
> }
>
> +unref:
> + bdrv_unref(target_bs);
> out:
> aio_context_release(aio_context);
> return job;
With this fixed:
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
On 5/13/19 7:13 AM, Kevin Wolf wrote:
> Am 10.05.2019 um 23:52 hat John Snow geschrieben:
>> If the bitmap can't be used for whatever reason, we skip putting down
>> the reference. Fix that.
>>
>> In practice, this means that if you attempt to gracefully exit QEMU
>> after a backup command being rejected, bdrv_close_all will fail and
>> tell you some unpleasant things via assert().
>>
>> Reported-by: aihua liang <aliang@redhat.com>
>> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1703916
>> Signed-off-by: John Snow <jsnow@redhat.com>
>> ---
>> blockdev.c | 12 +++++-------
>> 1 file changed, 5 insertions(+), 7 deletions(-)
>>
>> diff --git a/blockdev.c b/blockdev.c
>> index 79fbac8450..278ecdd122 100644
>> --- a/blockdev.c
>> +++ b/blockdev.c
>> @@ -3525,8 +3525,7 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
>> if (set_backing_hd) {
>> bdrv_set_backing_hd(target_bs, source, &local_err);
>> if (local_err) {
>> - bdrv_unref(target_bs);
>> - goto out;
>> + goto unref;
>> }
>> }
>>
>> @@ -3534,11 +3533,10 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
>> bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
>> if (!bmap) {
>> error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
>> - bdrv_unref(target_bs);
>> - goto out;
>> + goto unref;
>> }
>> if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_DEFAULT, errp)) {
>> - goto out;
>> + goto unref;
>> }
>> }
>> if (!backup->auto_finalize) {
>> @@ -3552,12 +3550,12 @@ static BlockJob *do_drive_backup(DriveBackup *backup, JobTxn *txn,
>> backup->sync, bmap, backup->compress,
>> backup->on_source_error, backup->on_target_error,
>> job_flags, NULL, NULL, txn, &local_err);
>> - bdrv_unref(target_bs);
>> if (local_err != NULL) {
>> error_propagate(errp, local_err);
>> - goto out;
>
> Please leave a 'goto unref' here so we can later add more code without
> modifying unrelated error paths (or, more likely, forgetting to modify
> them).
>
Oh, that makes sense.
>> }
>>
>> +unref:
>> + bdrv_unref(target_bs);
>> out:
>> aio_context_release(aio_context);
>> return job;
>
> With this fixed:
> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
>
Thanks!
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