From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=39685 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pwcrt-0002uD-T7 for qemu-devel@nongnu.org; Mon, 07 Mar 2011 11:01:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pwcrs-0001Vz-V4 for qemu-devel@nongnu.org; Mon, 07 Mar 2011 11:01:09 -0500 Received: from e1.ny.us.ibm.com ([32.97.182.141]:43694) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pwcrs-0001Vp-S3 for qemu-devel@nongnu.org; Mon, 07 Mar 2011 11:01:08 -0500 Received: from d01dlp01.pok.ibm.com (d01dlp01.pok.ibm.com [9.56.224.56]) by e1.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p27FpJ3G005655 for ; Mon, 7 Mar 2011 10:51:19 -0500 Received: from d01relay04.pok.ibm.com (d01relay04.pok.ibm.com [9.56.227.236]) by d01dlp01.pok.ibm.com (Postfix) with ESMTP id 54F8F38C803C for ; Mon, 7 Mar 2011 11:01:06 -0500 (EST) Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p27G17HM183334 for ; Mon, 7 Mar 2011 11:01:08 -0500 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p27FwhW3032345 for ; Mon, 7 Mar 2011 08:58:44 -0700 Date: Mon, 7 Mar 2011 10:01:04 -0600 From: Ryan Harper Message-ID: <20110307160104.GW23238@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Qemu-devel] [PATCH v2] Don't allow multiwrites against a block device without underlying medium List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Stefan Hajnoczi If the block device has been closed, we no longer have a medium to submit IO against, check for this before submitting io. This prevents a segfault further in the code where we dereference elements of the block driver. Signed-off-by: Ryan Harper --- v1->v2: - move bs->drv check to top of function to match other bdrv_ functions - fill out reqs response with error code before returning -1. block.c | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-) diff --git a/block.c b/block.c index f7d91a2..1544d81 100644 --- a/block.c +++ b/block.c @@ -2398,6 +2398,14 @@ int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) MultiwriteCB *mcb; int i; + /* don't submit writes if we don't have a medium */ + if (bs->drv == NULL) { + for (i = 0; i < num_reqs; i++) { + reqs[i].error = -ENOMEDIUM; + } + return -1; + } + if (num_reqs == 0) { return 0; } -- 1.7.1 -- Ryan Harper Software Engineer; Linux Technology Center IBM Corp., Austin, Tx ryanh@us.ibm.com