From patchwork Wed Aug 12 21:01:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 11711351 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4225413B6 for ; Wed, 12 Aug 2020 21:01:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 239F6221E2 for ; Wed, 12 Aug 2020 21:01:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b="UD0VLXTj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726030AbgHLVB2 (ORCPT ); Wed, 12 Aug 2020 17:01:28 -0400 Received: from ale.deltatee.com ([204.191.154.188]:38418 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726564AbgHLVB2 (ORCPT ); Wed, 12 Aug 2020 17:01:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:Content-Transfer-Encoding:MIME-Version: Message-Id:Date:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=kGiEj/z+vdf+Ey+9R6ahin3vijWbPQNp/8asyFRpxHo=; b=UD0VLXTjuHTts8bUCzA8XKl0vD 15m73oV6oKBtjBUKkziwo3hSYECesrbvwqPYp9djMlLGyslrSKAxU41EK1ODx8Ekc4p3mIhqLTs1Y YR8jzADiMdicWWk/tvdBdAnWJ3AJCx+jfyrg+qvXjnRH51kRl9PEUb8rKHYhGPNK7zGzYrbezcdDv PzOCj/b0gV5S2k2kFG7etvvYkBGFqSFKBg99x13NG5bO7WODqzzqITOLr55JGuWFH3p/UuhAClPX2 +ZwllEa+NSgwbF5v+ZY8j2Oukezs+lKG6qB5cXBfJUkn9rrLRP4HsBe9q9ozcMW2HHKbmzX8PpH2R rmQkjdNQ==; Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1k5xsD-0003Wb-D4; Wed, 12 Aug 2020 15:01:26 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.92) (envelope-from ) id 1k5xsB-0001s9-84; Wed, 12 Aug 2020 15:01:23 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, Keith Busch Cc: Christoph Hellwig , Sagi Grimberg , Keith Busch , Jens Axboe , Logan Gunthorpe Date: Wed, 12 Aug 2020 15:01:19 -0600 Message-Id: <20200812210119.7155-1-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me, keith.busch@wdc.com, axboe@kernel.dk, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on ale.deltatee.com X-Spam-Level: X-Spam-Status: No, score=-8.7 required=5.0 tests=ALL_TRUSTED,BAYES_00, GREYLIST_ISWHITE,MYRULES_NO_TEXT,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Subject: [RESEND PATCH] nvme: Use spin_lock_irqsave() when taking the ctrl->lock X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org When locking the ctrl->lock spinlock IRQs need to be disabled to avoid a dead lock. The new spin_lock() calls recently added produce the following lockdep warning when running the blktest nvme/003: ================================ WARNING: inconsistent lock state -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. ksoftirqd/2/22 [HC0[0]:SC1[1]:HE0:SE0] takes: ffff888276a8c4c0 (&ctrl->lock){+.?.}-{2:2}, at: nvme_keep_alive_end_io+0x50/0xc0 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x164/0x500 _raw_spin_lock+0x28/0x40 nvme_get_effects_log+0x37/0x1c0 nvme_init_identify+0x9e4/0x14f0 nvme_reset_work+0xadd/0x2360 process_one_work+0x66b/0xb70 worker_thread+0x6e/0x6c0 kthread+0x1e7/0x210 ret_from_fork+0x22/0x30 irq event stamp: 1449221 hardirqs last enabled at (1449220): [] ktime_get+0xf9/0x140 hardirqs last disabled at (1449221): [] _raw_spin_lock_irqsave+0x25/0x60 softirqs last enabled at (1449210): [] __do_softirq+0x447/0x595 softirqs last disabled at (1449215): [] run_ksoftirqd+0x35/0x50 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&ctrl->lock); lock(&ctrl->lock); *** DEADLOCK *** no locks held by ksoftirqd/2/22. stack backtrace: CPU: 2 PID: 22 Comm: ksoftirqd/2 Not tainted 5.8.0-rc4-eid-vmlocalyes-dbg-00157-g7236657c6b3a #1450 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack+0xc8/0x11a print_usage_bug.cold.63+0x235/0x23e mark_lock+0xa9c/0xcf0 __lock_acquire+0xd9a/0x2b50 lock_acquire+0x164/0x500 _raw_spin_lock_irqsave+0x40/0x60 nvme_keep_alive_end_io+0x50/0xc0 blk_mq_end_request+0x158/0x210 nvme_complete_rq+0x146/0x500 nvme_loop_complete_rq+0x26/0x30 [nvme_loop] blk_done_softirq+0x187/0x1e0 __do_softirq+0x118/0x595 run_ksoftirqd+0x35/0x50 smpboot_thread_fn+0x1d3/0x310 kthread+0x1e7/0x210 ret_from_fork+0x22/0x30 Fixes: be93e87e7802 ("nvme: support for multiple Command Sets Supported and Effects log pages") Signed-off-by: Logan Gunthorpe --- drivers/nvme/host/core.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) base-commit: 4d3c0eaf0d44a4f8f7d53b7835e670eafc96c450 -- 2.20.1 diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 15abc00db3d3..312614467adb 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2971,15 +2971,16 @@ int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp, u8 csi, static struct nvme_cel *nvme_find_cel(struct nvme_ctrl *ctrl, u8 csi) { struct nvme_cel *cel, *ret = NULL; + unsigned long flags; - spin_lock(&ctrl->lock); + spin_lock_irqsave(&ctrl->lock, flags); list_for_each_entry(cel, &ctrl->cels, entry) { if (cel->csi == csi) { ret = cel; break; } } - spin_unlock(&ctrl->lock); + spin_unlock_irqrestore(&ctrl->lock, flags); return ret; } @@ -2988,6 +2989,7 @@ static int nvme_get_effects_log(struct nvme_ctrl *ctrl, u8 csi, struct nvme_effects_log **log) { struct nvme_cel *cel = nvme_find_cel(ctrl, csi); + unsigned long flags; int ret; if (cel) @@ -3006,9 +3008,9 @@ static int nvme_get_effects_log(struct nvme_ctrl *ctrl, u8 csi, cel->csi = csi; - spin_lock(&ctrl->lock); + spin_lock_irqsave(&ctrl->lock, flags); list_add_tail(&cel->entry, &ctrl->cels); - spin_unlock(&ctrl->lock); + spin_unlock_irqrestore(&ctrl->lock, flags); out: *log = &cel->log; return 0;