From patchwork Thu Apr 14 22:56:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Wang X-Patchwork-Id: 561495 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 4AD8EC433EF for ; Thu, 14 Apr 2022 22:56:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347387AbiDNW6o (ORCPT ); Thu, 14 Apr 2022 18:58:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347377AbiDNW6n (ORCPT ); Thu, 14 Apr 2022 18:58:43 -0400 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 48F469399E for ; Thu, 14 Apr 2022 15:56:13 -0700 (PDT) X-UUID: dc81b414a0ba4fb197bfe0ee06e92b9d-20220415 X-UUID: dc81b414a0ba4fb197bfe0ee06e92b9d-20220415 Received: from mtkmbs10n1.mediatek.inc [(172.21.101.34)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 224464746; Fri, 15 Apr 2022 06:56:08 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.3; Fri, 15 Apr 2022 06:56:06 +0800 Received: from mtkswgap22.mediatek.inc (172.21.77.33) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Fri, 15 Apr 2022 06:56:06 +0800 From: To: , CC: , , , , , , , , , , , , , , , , , , , , , , , , "Deren Wu" Subject: [PATCH] mt76: mt7921: fix kernel crash at mt7921_pci_remove Date: Fri, 15 Apr 2022 06:56:05 +0800 Message-ID: X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org From: Sean Wang The crash log shown it is possible that mt7921_irq_handler is called while devm_free_irq is being handled so mt76_free_device need to be postponed until devm_free_irq is completed to solve the crash we free the mt76 device too early. [ 9299.339655] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 9299.339705] #PF: supervisor read access in kernel mode [ 9299.339735] #PF: error_code(0x0000) - not-present page [ 9299.339768] PGD 0 P4D 0 [ 9299.339786] Oops: 0000 [#1] SMP PTI [ 9299.339812] CPU: 1 PID: 1624 Comm: prepare-suspend Not tainted 5.15.14-1.fc32.qubes.x86_64 #1 [ 9299.339863] Hardware name: Xen HVM domU, BIOS 4.14.3 01/20/2022 [ 9299.339901] RIP: 0010:mt7921_irq_handler+0x1e/0x70 [mt7921e] [ 9299.340048] RSP: 0018:ffffa81b80c27cb0 EFLAGS: 00010082 [ 9299.340081] RAX: 0000000000000000 RBX: ffff98a4cb752020 RCX: ffffffffa96211c5 [ 9299.340123] RDX: 0000000000000000 RSI: 00000000000d4204 RDI: ffff98a4cb752020 [ 9299.340165] RBP: ffff98a4c28a62a4 R08: ffff98a4c37a96c0 R09: 0000000080150011 [ 9299.340207] R10: 0000000040000000 R11: 0000000000000000 R12: ffff98a4c4eaa080 [ 9299.340249] R13: ffff98a4c28a6360 R14: ffff98a4cb752020 R15: ffff98a4c28a6228 [ 9299.340297] FS: 00007260840d3740(0000) GS:ffff98a4ef700000(0000) knlGS:0000000000000000 [ 9299.340345] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9299.340383] CR2: 0000000000000008 CR3: 0000000004c56001 CR4: 0000000000770ee0 [ 9299.340432] PKRU: 55555554 [ 9299.340449] Call Trace: [ 9299.340467] [ 9299.340485] __free_irq+0x221/0x350 [ 9299.340527] free_irq+0x30/0x70 [ 9299.340553] devm_free_irq+0x55/0x80 [ 9299.340579] mt7921_pci_remove+0x2f/0x40 [mt7921e] [ 9299.340616] pci_device_remove+0x3b/0xa0 [ 9299.340651] __device_release_driver+0x17a/0x240 [ 9299.340686] device_driver_detach+0x3c/0xa0 [ 9299.340714] unbind_store+0x113/0x130 [ 9299.340740] kernfs_fop_write_iter+0x124/0x1b0 [ 9299.340775] new_sync_write+0x15c/0x1f0 [ 9299.340806] vfs_write+0x1d2/0x270 [ 9299.340831] ksys_write+0x67/0xe0 [ 9299.340857] do_syscall_64+0x3b/0x90 [ 9299.340887] entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: 5c14a5f944b9 ("mt76: mt7921: introduce mt7921e support") Reported-by: ThinerLogoer Signed-off-by: Deren Wu Signed-off-by: Sean Wang --- drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c index 062e2b422478..b5fb22b8e086 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c @@ -119,7 +119,6 @@ static void mt7921e_unregister_device(struct mt7921_dev *dev) mt7921_mcu_exit(dev); tasklet_disable(&dev->irq_tasklet); - mt76_free_device(&dev->mt76); } static u32 __mt7921_reg_addr(struct mt7921_dev *dev, u32 addr) @@ -356,6 +355,7 @@ static void mt7921_pci_remove(struct pci_dev *pdev) mt7921e_unregister_device(dev); devm_free_irq(&pdev->dev, pdev->irq, dev); + mt76_free_device(&dev->mt76); pci_free_irq_vectors(pdev); }