From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90C3AC04EB8 for ; Fri, 7 Dec 2018 03:04:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4DEF52083D for ; Fri, 7 Dec 2018 03:04:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4DEF52083D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-block-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725939AbeLGDEE (ORCPT ); Thu, 6 Dec 2018 22:04:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55546 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725948AbeLGDEE (ORCPT ); Thu, 6 Dec 2018 22:04:04 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D4C559F754; Fri, 7 Dec 2018 03:04:03 +0000 (UTC) Received: from localhost (ovpn-8-23.pek2.redhat.com [10.72.8.23]) by smtp.corp.redhat.com (Postfix) with ESMTP id 006A260C5C; Fri, 7 Dec 2018 03:03:58 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Ming Lei , Christoph Hellwig , linux-nvme@lists.infradead.org, David Milburn Subject: [PATCH V2] blk-mq: re-build queue map in case of kdump kernel Date: Fri, 7 Dec 2018 11:03:53 +0800 Message-Id: <20181207030353.27575-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Fri, 07 Dec 2018 03:04:03 +0000 (UTC) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Now almost all .map_queues() implementation based on managed irq affinity doesn't update queue mapping and it just retrieves the old built mapping, so if nr_hw_queues is changed, the mapping talbe includes stale mapping. And only blk_mq_map_queues() may rebuild the mapping talbe. One case is that we limit .nr_hw_queues as 1 in case of kdump kernel. However, drivers often builds queue mapping before allocating tagset via pci_alloc_irq_vectors_affinity(), but set->nr_hw_queues can be set as 1 in case of kdump kernel, so wrong queue mapping is used, and kernel panic[1] is observed during booting. This patch fixes the kernel panic triggerd on nvme by rebulding the mapping table via blk_mq_map_queues(). [1] kernel panic log [ 4.438371] nvme nvme0: 16/0/0 default/read/poll queues [ 4.443277] BUG: unable to handle kernel NULL pointer dereference at 0000000000000098 [ 4.444681] PGD 0 P4D 0 [ 4.445367] Oops: 0000 [#1] SMP NOPTI [ 4.446342] CPU: 3 PID: 201 Comm: kworker/u33:10 Not tainted 4.20.0-rc5-00664-g5eb02f7ee1eb-dirty #459 [ 4.447630] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-2.fc27 04/01/2014 [ 4.448689] Workqueue: nvme-wq nvme_scan_work [nvme_core] [ 4.449368] RIP: 0010:blk_mq_map_swqueue+0xfb/0x222 [ 4.450596] Code: 04 f5 20 28 ef 81 48 89 c6 39 55 30 76 93 89 d0 48 c1 e0 04 48 03 83 f8 05 00 00 48 8b 00 42 8b 3c 28 48 8b 43 58 48 8b 04 f8 <48> 8b b8 98 00 00 00 4c 0f a3 37 72 42 f0 4c 0f ab 37 66 8b b8 f6 [ 4.453132] RSP: 0018:ffffc900023b3cd8 EFLAGS: 00010286 [ 4.454061] RAX: 0000000000000000 RBX: ffff888174448000 RCX: 0000000000000001 [ 4.456480] RDX: 0000000000000001 RSI: ffffe8feffc506c0 RDI: 0000000000000001 [ 4.458750] RBP: ffff88810722d008 R08: ffff88817647a880 R09: 0000000000000002 [ 4.464580] R10: ffffc900023b3c10 R11: 0000000000000004 R12: ffff888174448538 [ 4.467803] R13: 0000000000000004 R14: 0000000000000001 R15: 0000000000000001 [ 4.469220] FS: 0000000000000000(0000) GS:ffff88817bac0000(0000) knlGS:0000000000000000 [ 4.471554] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4.472464] CR2: 0000000000000098 CR3: 0000000174e4e001 CR4: 0000000000760ee0 [ 4.474264] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4.476007] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4.477061] PKRU: 55555554 [ 4.477464] Call Trace: [ 4.478731] blk_mq_init_allocated_queue+0x36a/0x3ad [ 4.479595] blk_mq_init_queue+0x32/0x4e [ 4.480178] nvme_validate_ns+0x98/0x623 [nvme_core] [ 4.480963] ? nvme_submit_sync_cmd+0x1b/0x20 [nvme_core] [ 4.481685] ? nvme_identify_ctrl.isra.8+0x70/0xa0 [nvme_core] [ 4.482601] nvme_scan_work+0x23a/0x29b [nvme_core] [ 4.483269] ? _raw_spin_unlock_irqrestore+0x25/0x38 [ 4.483930] ? try_to_wake_up+0x38d/0x3b3 [ 4.484478] ? process_one_work+0x179/0x2fc [ 4.485118] process_one_work+0x1d3/0x2fc [ 4.485655] ? rescuer_thread+0x2ae/0x2ae [ 4.486196] worker_thread+0x1e9/0x2be [ 4.486841] kthread+0x115/0x11d [ 4.487294] ? kthread_park+0x76/0x76 [ 4.487784] ret_from_fork+0x3a/0x50 [ 4.488322] Modules linked in: nvme nvme_core qemu_fw_cfg virtio_scsi ip_tables [ 4.489428] Dumping ftrace buffer: [ 4.489939] (ftrace buffer empty) [ 4.490492] CR2: 0000000000000098 [ 4.491052] ---[ end trace 03cd268ad5a86ff7 ]--- Cc: Christoph Hellwig Cc: linux-nvme@lists.infradead.org Cc: David Milburn Signed-off-by: Ming Lei --- block/blk-mq.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 900550594651..65770da99159 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2960,7 +2960,7 @@ static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) static int blk_mq_update_queue_map(struct blk_mq_tag_set *set) { - if (set->ops->map_queues) { + if (set->ops->map_queues && !is_kdump_kernel()) { int i; /* @@ -3030,6 +3030,7 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) */ if (is_kdump_kernel()) { set->nr_hw_queues = 1; + set->nr_maps = 1; set->queue_depth = min(64U, set->queue_depth); } /* @@ -3051,7 +3052,7 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) GFP_KERNEL, set->numa_node); if (!set->map[i].mq_map) goto out_free_mq_map; - set->map[i].nr_queues = set->nr_hw_queues; + set->map[i].nr_queues = is_kdump_kernel() ? 1 : set->nr_hw_queues; } ret = blk_mq_update_queue_map(set); -- 2.9.5