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AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D58E6307CDEA; Fri, 13 Sep 2019 22:26:32 +0000 (UTC) Received: from [10.18.17.38] (dhcp-17-38.bos.redhat.com [10.18.17.38]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8F3195D9CD; Fri, 13 Sep 2019 22:26:31 +0000 (UTC) To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20190911150054.90936-1-vsementsov@virtuozzo.com> <20190911150054.90936-4-vsementsov@virtuozzo.com> From: John Snow Openpgp: preference=signencrypt Autocrypt: addr=jsnow@redhat.com; prefer-encrypt=mutual; keydata= mQINBFTKefwBEAChvwqYC6saTzawbih87LqBYq0d5A8jXYXaiFMV/EvMSDqqY4EY6whXliNO IYzhgrPEe7ZmPxbCSe4iMykjhwMh5byIHDoPGDU+FsQty2KXuoxto+ZdrP9gymAgmyqdk3aV vzzmCa3cOppcqKvA0Kqr10UeX/z4OMVV390V+DVWUvzXpda45/Sxup57pk+hyY52wxxjIqef rj8u5BN93s5uCVTus0oiVA6W+iXYzTvVDStMFVqnTxSxlpZoH5RGKvmoWV3uutByQyBPHW2U 1Y6n6iEZ9MlP3hcDqlo0S8jeP03HaD4gOqCuqLceWF5+2WyHzNfylpNMFVi+Hp0H/nSDtCvQ 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2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fam@euphon.net, kwolf@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com, mreitz@redhat.com, den@openvz.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 9/11/19 11:00 AM, Vladimir Sementsov-Ogievskiy wrote: > qmp_block_dirty_bitmap_add and do_block_dirty_bitmap_remove do acquire > aio context since 0a6c86d024c52b. But this is not enough: we also must > lock qcow2 mutex when access in-image metadata. Especially it concerns > freeing qcow2 clusters. > > To achieve this, move qcow2_can_store_new_dirty_bitmap and > qcow2_remove_persistent_dirty_bitmap to coroutine context. > > Since we work in coroutines in correct aio context, we don't need > context acquiring in blockdev.c anymore, drop it. > > Signed-off-by: Vladimir Sementsov-Ogievskiy It makes sense to me given the context, but I'll want Kevin or Max to eye it over for locking correctness, admittedly. Here's my good faith RB: Reviewed-by: John Snow (I'm not so sure about the aio_wait_kick. Why is that needed here? ... oh, 4720cbeea1f42fd905fc69338fd42b191e58b412 explains why. I suppose any synchronous caller of a co_ function needs to make sure that the entry shim kicks on the way out. This seems very easy to get wrong, doesn't it?)