From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Date: Tue, 19 Feb 2019 18:37:09 -0800 Subject: [Cluster-devel] [dm-devel] [PATCH V15 00/18] block: support multi-page bvec In-Reply-To: <20190220011719.GA13035@ming.t460p> References: <20190215111324.30129-1-ming.lei@redhat.com> <1550250855.31902.102.camel@acm.org> <20190217131128.GB7296@ming.t460p> <1550593699.31902.115.camel@acm.org> <20190220011719.GA13035@ming.t460p> Message-ID: <8253d52d-a77a-b008-1fbd-f2f0a794a022@acm.org> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On 2/19/19 5:17 PM, Ming Lei wrote: > On Tue, Feb 19, 2019 at 08:28:19AM -0800, Bart Van Assche wrote: >> With this patch applied test nvmeof-mp/002 fails as follows: >> >> [ 694.700400] kernel BUG at lib/sg_pool.c:103! >> [ 694.705932] invalid opcode: 0000 [#1] PREEMPT SMP KASAN >> [ 694.708297] CPU: 2 PID: 349 Comm: kworker/2:1H Tainted: G B 5.0.0-rc6-dbg+ #2 >> [ 694.711730] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 >> [ 694.715113] Workqueue: kblockd blk_mq_run_work_fn >> [ 694.716894] RIP: 0010:sg_alloc_table_chained+0xe5/0xf0 >> [ 694.758222] Call Trace: >> [ 694.759645] nvme_rdma_queue_rq+0x2aa/0xcc0 [nvme_rdma] >> [ 694.764915] blk_mq_try_issue_directly+0x2a5/0x4b0 >> [ 694.771779] blk_insert_cloned_request+0x11e/0x1c0 >> [ 694.778417] dm_mq_queue_rq+0x3d1/0x770 >> [ 694.793400] blk_mq_dispatch_rq_list+0x5fc/0xb10 >> [ 694.798386] blk_mq_sched_dispatch_requests+0x2f7/0x300 >> [ 694.803180] __blk_mq_run_hw_queue+0xd6/0x180 >> [ 694.808933] blk_mq_run_work_fn+0x27/0x30 >> [ 694.810315] process_one_work+0x4f1/0xa40 >> [ 694.813178] worker_thread+0x67/0x5b0 >> [ 694.814487] kthread+0x1cf/0x1f0 >> [ 694.819134] ret_from_fork+0x24/0x30 >> >> The code in sg_pool.c that triggers the BUG() statement is as follows: >> >> int sg_alloc_table_chained(struct sg_table *table, int nents, >> struct scatterlist *first_chunk) >> { >> int ret; >> >> BUG_ON(!nents); >> [ ... ] >> >> Bart. > > I can reproduce this issue("kernel BUG at lib/sg_pool.c:103") without mp-bvec patches, > so looks it isn't the fault of this patchset. Thanks Ming for your feedback. Jens, I don't see that issue with kernel v5.0-rc6. Does that mean that the sg_pool BUG() is a regression in your for-next branch that predates Ming's multi-page bvec patch series? Thanks, Bart.