From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:59850 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751342AbcBBBDM (ORCPT ); Mon, 1 Feb 2016 20:03:12 -0500 Subject: Patch "block: Always check queue limits for cloned requests" has been added to the 4.3-stable tree To: hare@suse.de, axboe@fb.com, emilne@redhat.com, gregkh@linuxfoundation.org, jmoyer@redhat.com, snitzer@redhat.com Cc: , From: Date: Mon, 01 Feb 2016 17:03:11 -0800 Message-ID: <1454374991120219@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled block: Always check queue limits for cloned requests to the 4.3-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: block-always-check-queue-limits-for-cloned-requests.patch and it can be found in the queue-4.3 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From bf4e6b4e757488dee1b6a581f49c7ac34cd217f8 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Thu, 26 Nov 2015 08:46:57 +0100 Subject: block: Always check queue limits for cloned requests From: Hannes Reinecke commit bf4e6b4e757488dee1b6a581f49c7ac34cd217f8 upstream. When a cloned request is retried on other queues it always needs to be checked against the queue limits of that queue. Otherwise the calculations for nr_phys_segments might be wrong, leading to a crash in scsi_init_sgtable(). To clarify this the patch renames blk_rq_check_limits() to blk_cloned_rq_check_limits() and removes the symbol export, as the new function should only be used for cloned requests and never exported. Cc: Mike Snitzer Cc: Ewan Milne Cc: Jeff Moyer Signed-off-by: Hannes Reinecke Fixes: e2a60da74 ("block: Clean up special command handling logic") Acked-by: Mike Snitzer Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- block/blk-core.c | 21 +++++++-------------- include/linux/blkdev.h | 1 - 2 files changed, 7 insertions(+), 15 deletions(-) --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2023,7 +2023,8 @@ void submit_bio(int rw, struct bio *bio) EXPORT_SYMBOL(submit_bio); /** - * blk_rq_check_limits - Helper function to check a request for the queue limit + * blk_cloned_rq_check_limits - Helper function to check a cloned request + * for new the queue limits * @q: the queue * @rq: the request being checked * @@ -2034,20 +2035,13 @@ EXPORT_SYMBOL(submit_bio); * after it is inserted to @q, it should be checked against @q before * the insertion using this generic function. * - * This function should also be useful for request stacking drivers - * in some cases below, so export this function. * Request stacking drivers like request-based dm may change the queue - * limits while requests are in the queue (e.g. dm's table swapping). - * Such request stacking drivers should check those requests against - * the new queue limits again when they dispatch those requests, - * although such checkings are also done against the old queue limits - * when submitting requests. + * limits when retrying requests on other queues. Those requests need + * to be checked against the new queue limits again during dispatch. */ -int blk_rq_check_limits(struct request_queue *q, struct request *rq) +static int blk_cloned_rq_check_limits(struct request_queue *q, + struct request *rq) { - if (!rq_mergeable(rq)) - return 0; - if (blk_rq_sectors(rq) > blk_queue_get_max_sectors(q, rq->cmd_flags)) { printk(KERN_ERR "%s: over max size limit.\n", __func__); return -EIO; @@ -2067,7 +2061,6 @@ int blk_rq_check_limits(struct request_q return 0; } -EXPORT_SYMBOL_GPL(blk_rq_check_limits); /** * blk_insert_cloned_request - Helper for stacking drivers to submit a request @@ -2079,7 +2072,7 @@ int blk_insert_cloned_request(struct req unsigned long flags; int where = ELEVATOR_INSERT_BACK; - if (blk_rq_check_limits(q, rq)) + if (blk_cloned_rq_check_limits(q, rq)) return -EIO; if (rq->rq_disk && --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -767,7 +767,6 @@ extern void blk_rq_set_block_pc(struct r extern void blk_requeue_request(struct request_queue *, struct request *); extern void blk_add_request_payload(struct request *rq, struct page *page, unsigned int len); -extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); extern int blk_lld_busy(struct request_queue *q); extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, struct bio_set *bs, gfp_t gfp_mask, Patches currently in stable-queue which might be from hare@suse.de are queue-4.3/block-always-check-queue-limits-for-cloned-requests.patch