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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D92AEC433EF for ; Fri, 8 Jul 2022 17:08:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238517AbiGHRIS (ORCPT ); Fri, 8 Jul 2022 13:08:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232885AbiGHRIR (ORCPT ); Fri, 8 Jul 2022 13:08:17 -0400 Received: from mail-wm1-x336.google.com (mail-wm1-x336.google.com [IPv6:2a00:1450:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C12A675A0 for ; Fri, 8 Jul 2022 10:08:16 -0700 (PDT) Received: by mail-wm1-x336.google.com with SMTP id v67-20020a1cac46000000b003a1888b9d36so1535365wme.0 for ; Fri, 08 Jul 2022 10:08:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=rjtnXjJTM76a8uBuPAjTSUIAKlaLeiPacD9QEtS4qDw=; b=MDtkeEsInPqXPzZim3GXqcRJnQOfNrk0zyh69sg/F7vVFzZs7k4LbrmXCyoJMhe+pk hV6nsVlhB1c8j3aePLXYPVgjfKdkU6l80MZxTr3QLcbG11/Pkn1zcGUlv8v9uLrr+Y2R zUbnawCQw1MwEaiv2QUN9UWeC6sUxoBqBUMkGsmZnfBgcqnehNvhJ6lSuElTcEB5F4ov fnl76H5vXeqI5YM0r2YMAhMa7Oe2ouD2XUJMLO8XC02bnjHKvz8/Z/bRDT6kP06yvLlp E3VxyeGZdW978yMpMTQWBWvM8vblfY6+0by9evAAG1hP2wYpL7l/LhvUnhkHrHW2V5+B TUHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=rjtnXjJTM76a8uBuPAjTSUIAKlaLeiPacD9QEtS4qDw=; b=3L8NGcXQ6EPv81Jp1J2AKHed0UpIECxCEhXXM3qORX/aKr6JrUDrMw0EbwU0jBBwMm 2jZtDcvdKXLr/WUL1ywKZsFDIn9HKIgEn8+AJmwzS/vumnCz5+HUw/FTxHTixLsYv0Pc tAKiDUX1j0lP9Z5OilUZ0jcmuXjTv/LqIKzoYSTU7fwOg2XnH7tE9n98frhvPmt0IhKX YS6qBlLCDrzydaeuHsPzQJGqqsBOHLlgrgs6lUVmrgnJZz77F5b5SeTFp1CxgM1H4FY/ JgOLxey5ElbZMPjLsK2tu2OFUuuuC9CL3hKNerJWNydcDfvbUIgRggyH1emdednMDtWj PzHg== X-Gm-Message-State: AJIora/vj+m/CCnUwDtNL6TrDhCbiIQnt6RJnxXOQbp8LTExv1QZdqXm dUsno99dHaf473w+zDfvDAJMO58+pltzh6AU X-Google-Smtp-Source: AGRyM1uLwrXqWANfQe+1Wila+2ISVN7BYY7M0YDfWZQ2VfUWRzFwS//um4Nxt9sS7P6MX4Tl60U/tQ== X-Received: by 2002:a1c:7405:0:b0:3a2:de4f:5f07 with SMTP id p5-20020a1c7405000000b003a2de4f5f07mr840272wmc.117.1657300094872; Fri, 08 Jul 2022 10:08:14 -0700 (PDT) Received: from rainbowdash.office.codethink.co.uk ([167.98.27.226]) by smtp.gmail.com with ESMTPSA id k9-20020a5d4289000000b0021d9591c64fsm92701wrq.33.2022.07.08.10.08.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 08 Jul 2022 10:08:14 -0700 (PDT) From: Ben Dooks To: linux-kernel@vger.kernel.org, iommu@lists.linux.dev, iommu@lists.linux-foundation.org Cc: Sudip Mukherjee , Jude Onyenegecha , Ben Dooks Subject: [PATCH] swiotlb: ensure io_tlb_default_mem spinlock always initialised Date: Fri, 8 Jul 2022 18:08:11 +0100 Message-Id: <20220708170811.270589-1-ben.dooks@sifive.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the io_tlb_default_mem is used by a device that then gets used by the swiotlb code, the spinlock warning is triggered causing a lot of stack-trace. Fix this by making the structure's lock initialised at build time. Avoids the following BUG trigger: [ 3.046401] BUG: spinlock bad magic on CPU#3, kworker/u8:0/7 [ 3.046689] lock: io_tlb_default_mem+0x30/0x60, .magic: 00000000, .owner: /-1, .owner_cpu: 0 [ 3.047217] CPU: 3 PID: 7 Comm: kworker/u8:0 Not tainted 5.17.0-00056-g1e9bac738084-dirty #310 [ 3.048363] Workqueue: events_unbound deferred_probe_work_func [ 3.048892] Call Trace: [ 3.049224] [] dump_backtrace+0x1c/0x24 [ 3.049576] [] show_stack+0x2c/0x38 [ 3.049898] [] dump_stack_lvl+0x40/0x58 [ 3.050216] [] dump_stack+0x14/0x1c [ 3.050460] [] spin_dump+0x62/0x6e [ 3.050681] [] do_raw_spin_lock+0xb0/0xd0 [ 3.050934] [] _raw_spin_lock_irqsave+0x20/0x2c [ 3.051157] [] swiotlb_tbl_map_single+0xce/0x3da [ 3.051372] [] swiotlb_map+0x3a/0x15c [ 3.051668] [] dma_map_page_attrs+0x76/0x162 [ 3.051975] [] dw_pcie_host_init+0x326/0x3f2 Signed-off-by: Ben Dooks --- kernel/dma/swiotlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index cb50f8d38360..a707a944c39a 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -65,7 +65,7 @@ static bool swiotlb_force_bounce; static bool swiotlb_force_disable; -struct io_tlb_mem io_tlb_default_mem; +struct io_tlb_mem io_tlb_default_mem = { .lock = __SPIN_LOCK_UNLOCKED(io_tlb_default_mem.lock) } ; phys_addr_t swiotlb_unencrypted_base; -- 2.35.1