From patchwork Thu Jan 14 17:10:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 12020367 X-Patchwork-Delegate: kvalo@adurom.com 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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 D22E6C4332B for ; Thu, 14 Jan 2021 17:11:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9B0123B40 for ; Thu, 14 Jan 2021 17:11:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728044AbhANRLj (ORCPT ); Thu, 14 Jan 2021 12:11:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:55674 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727153AbhANRLj (ORCPT ); Thu, 14 Jan 2021 12:11:39 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id A284123B1C; Thu, 14 Jan 2021 17:10:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1610644257; bh=mcVu179EQmQ2dsA/z1BhV+rbOBlPLXyi4n0Y+HZHha0=; h=From:To:Cc:Subject:Date:From; b=K2hlPoOCN+xzq7zdAJB3cMUa8hagwcdRO8ttj6B+JDxp1Ap0eMSULvElg6TZUT4Y2 aN2jOpyeOqItenVvJU+C9jh6mvo06O1ANJRg/ylvroXVbGb+btdMQ8Rlq4iE/NOVaH oFfcKmmfgJO9SJ7iY5BJ4qsEK4E2HbL1/bIcIB3djDkMwOx+wYGQnbH72bU7CK5b54 c8FWYhHBFKQ3hoOmqVLJToQHlu0ipoV4UF+Brqb8syDR4AAnvOAopxSVMw8CQDQ3bZ 8t8S8N+IiURRLQQxuQnUTxaPtRw0uNoZ8eMsMTp/PxMRPw9Htb9riZ30SdRjQw1rHa B/ZRtWeOFtWiQ== From: Lorenzo Bianconi To: linux-wireless@vger.kernel.org Cc: lorenzo.bianconi@redhat.com, kuba@kernel.org, nbd@nbd.name, matthias_berndt@gmx.de, mozlima@gmail.com Subject: [PATCH wireless-drivers] mt7601u: fix rx buffer refcounting Date: Thu, 14 Jan 2021 18:10:52 +0100 Message-Id: <62b2380c8c2091834cfad05e1059b55f945bd114.1610643952.git.lorenzo@kernel.org> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Fix the following crash due to erroneous page refcounting: [ 32.445919] BUG: Bad page state in process swapper/1 pfn:11f65a [ 32.447409] page:00000000938f0632 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x11f65a [ 32.449605] flags: 0x8000000000000000() [ 32.450421] raw: 8000000000000000 ffffffff825b0148 ffffea00045ae988 0000000000000000 [ 32.451795] raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000 [ 32.452999] page dumped because: nonzero mapcount [ 32.453888] Modules linked in: [ 32.454492] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.11.0-rc2+ #1976 [ 32.455695] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-1.fc33 04/01/2014 [ 32.457157] Call Trace: [ 32.457636] [ 32.457993] dump_stack+0x77/0x97 [ 32.458576] bad_page.cold+0x65/0x96 [ 32.459198] get_page_from_freelist+0x46a/0x11f0 [ 32.460008] __alloc_pages_nodemask+0x10a/0x2b0 [ 32.460794] mt7601u_rx_tasklet+0x651/0x720 [ 32.461505] tasklet_action_common.constprop.0+0x6b/0xd0 [ 32.462343] __do_softirq+0x152/0x46c [ 32.462928] asm_call_irq_on_stack+0x12/0x20 [ 32.463610] [ 32.463953] do_softirq_own_stack+0x5b/0x70 [ 32.464582] irq_exit_rcu+0x9f/0xe0 [ 32.465028] common_interrupt+0xae/0x1a0 [ 32.465536] asm_common_interrupt+0x1e/0x40 [ 32.466071] RIP: 0010:default_idle+0x18/0x20 [ 32.468981] RSP: 0018:ffffc90000077f00 EFLAGS: 00000246 [ 32.469648] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 [ 32.470550] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff81aac3dd [ 32.471463] RBP: ffff88810022ab00 R08: 0000000000000001 R09: 0000000000000001 [ 32.472335] R10: 0000000000000046 R11: 0000000000005aa0 R12: 0000000000000000 [ 32.473235] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 32.474139] ? default_idle_call+0x4d/0x200 [ 32.474681] default_idle_call+0x74/0x200 [ 32.475192] do_idle+0x1d5/0x250 [ 32.475612] cpu_startup_entry+0x19/0x20 [ 32.476114] secondary_startup_64_no_verify+0xb0/0xbb [ 32.476765] Disabling lock debugging due to kernel taint Fixes: c869f77d6abb ("add mt7601u driver") Co-developed-by: Felix Fietkau Signed-off-by: Felix Fietkau Signed-off-by: Lorenzo Bianconi Acked-by: Jakub Kicinski --- drivers/net/wireless/mediatek/mt7601u/dma.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt7601u/dma.c b/drivers/net/wireless/mediatek/mt7601u/dma.c index 5f99054f535b..47710da5b2a5 100644 --- a/drivers/net/wireless/mediatek/mt7601u/dma.c +++ b/drivers/net/wireless/mediatek/mt7601u/dma.c @@ -152,8 +152,7 @@ mt7601u_rx_process_entry(struct mt7601u_dev *dev, struct mt7601u_dma_buf_rx *e) if (new_p) { /* we have one extra ref from the allocator */ - __free_pages(e->p, MT_RX_ORDER); - + put_page(e->p); e->p = new_p; } }