From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58783) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZsC3m-0007h8-Vd for qemu-devel@nongnu.org; Fri, 30 Oct 2015 11:57:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZsC3m-0001iJ-7g for qemu-devel@nongnu.org; Fri, 30 Oct 2015 11:57:46 -0400 From: Stefan Hajnoczi Date: Fri, 30 Oct 2015 15:57:41 +0000 Message-Id: <1446220661-18792-1-git-send-email-stefanha@redhat.com> Subject: [Qemu-devel] [PATCH] blockdev: acquire AioContext in hmp_commit() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , "Denis V. Lunev" , Stefan Hajnoczi , Markus Armbruster , qemu-block@nongnu.org This one slipped through. Although we acquire AioContext when committing all devices we don't for just a single device. AioContext must be acquired before calling bdrv_*() functions to synchronize access with other threads that may be using the AioContext. Signed-off-by: Stefan Hajnoczi --- blockdev.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/blockdev.c b/blockdev.c index 18712d2..d611779 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1120,6 +1120,9 @@ void hmp_commit(Monitor *mon, const QDict *qdict) if (!strcmp(device, "all")) { ret = bdrv_commit_all(); } else { + BlockDriverState *bs; + AioContext *aio_context; + blk = blk_by_name(device); if (!blk) { monitor_printf(mon, "Device '%s' not found\n", device); @@ -1129,7 +1132,14 @@ void hmp_commit(Monitor *mon, const QDict *qdict) monitor_printf(mon, "Device '%s' has no medium\n", device); return; } - ret = bdrv_commit(blk_bs(blk)); + + bs = blk_bs(blk); + aio_context = bdrv_get_aio_context(bs); + aio_context_acquire(aio_context); + + ret = bdrv_commit(bs); + + aio_context_release(aio_context); } if (ret < 0) { monitor_printf(mon, "'commit' error for '%s': %s\n", device, -- 2.4.3