From patchwork Fri Aug 6 10:35:09 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Loic Poulain X-Patchwork-Id: 12423177 X-Patchwork-Delegate: kuba@kernel.org 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 B8616C4338F for ; Fri, 6 Aug 2021 10:25:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 945B061163 for ; Fri, 6 Aug 2021 10:25:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245052AbhHFKZO (ORCPT ); Fri, 6 Aug 2021 06:25:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58740 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244928AbhHFKZM (ORCPT ); Fri, 6 Aug 2021 06:25:12 -0400 Received: from mail-wr1-x42d.google.com (mail-wr1-x42d.google.com [IPv6:2a00:1450:4864:20::42d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98A66C061798 for ; Fri, 6 Aug 2021 03:24:56 -0700 (PDT) Received: by mail-wr1-x42d.google.com with SMTP id k4so10464904wrc.0 for ; Fri, 06 Aug 2021 03:24:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=1M+kjBe5LJfHMKPYebEvjyNaiKWDMDU0Hnt7bpr7e5A=; b=SyY5P3/3fn3OPSGo81KmIl2K9Y502cNWmKbU9aTw7C+3CMdbgYAMOdrU0sphIJVJaf A4qkFfiU+075rWAkUPF3xkwV0v2K2kvwD+XgvgHliCYW5CBMvwzm4nf0TwECQvZMVV10 LvGbpOrinF4IpxYj6+F9M69H0Gm5I0JD81bhT+SeiEXkqUUbAZwP0alzGz/76+D1vv0/ 8QvQA7FyThN88MOFBp8GCCfY9iuTZMPRCaxyQR6Ro6b+Je1y96jRbrdn2rcKG5cXUaxx Iq3cSXTbP7T75vjY22yR7POqfg2iumeMN8q3svM7RijFlkg134qZKrZQ/kRs3+IWsXi9 g2pQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=1M+kjBe5LJfHMKPYebEvjyNaiKWDMDU0Hnt7bpr7e5A=; b=A8x84wlAQGYFno1sNdzuOnr9KEnxcEOgvSUV8WYV2hsyaaXfSmB1cG4JtuSJhvqvWy luazIH3HUYF0G9FlXXBs1di8nc2fbnoP4K13CuHBnOk/pIFoZOZvY1+PcqlaEmm81y61 O9i59exDKDiBgWBCSUuOeaC9TZyI3io5qi+b3yaowd4rBRwAa6f9NBbYRh8YeXCRaoiq lyyPG1F4vkl5mw4cv7IRWZMSPuCgyj9U9N8DJeDZ+yd2CMgrHYnKA5IkX3TF5J6nqzb0 38wFHL0qZd5qiCGJk/UA+uiMikSLQLNVAaW7JRkijswyr1/uOrO8plISM2Mjamu5228r geMA== X-Gm-Message-State: AOAM533kyt7Xmh2FzvyZP9ILDU+9fcpomPAAJA9NNFs9nyDR1EJAqu1N 6LyHnuIdRsdhDaHgY7H8a6WRkg== X-Google-Smtp-Source: ABdhPJxSzwnrWJd6HOIHDdO0i5FgxOaiJVWQPX9HROVajB1M+Pbg6yh5sjgRNWN0X88hjVAkTPTQvQ== X-Received: by 2002:a5d:4a84:: with SMTP id o4mr9729993wrq.273.1628245495152; Fri, 06 Aug 2021 03:24:55 -0700 (PDT) Received: from localhost.localdomain ([2a01:e0a:82c:5f0:69b5:b274:5cfc:ef2]) by smtp.gmail.com with ESMTPSA id k17sm9046540wrw.53.2021.08.06.03.24.54 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 06 Aug 2021 03:24:54 -0700 (PDT) From: Loic Poulain To: davem@davemloft.net, kuba@kernel.org Cc: netdev@vger.kernel.org, ryazanov.s.a@gmail.com, Loic Poulain , stable@vger.kernel.org Subject: [PATCH net-next] net: wwan: mhi_wwan_ctrl: Fix possible deadlock Date: Fri, 6 Aug 2021 12:35:09 +0200 Message-Id: <1628246109-27425-1-git-send-email-loic.poulain@linaro.org> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Lockdep detected possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mhiwwan->rx_lock); local_irq_disable(); lock(&mhi_cntrl->pm_lock); lock(&mhiwwan->rx_lock); lock(&mhi_cntrl->pm_lock); *** DEADLOCK *** To prevent this we need to disable the soft-interrupts when taking the rx_lock. Cc: stable@vger.kernel.org Fixes: fa588eba632d ("net: Add Qcom WWAN control driver") Reported-by: Thomas Perrot Signed-off-by: Loic Poulain Reviewed-by: Sergey Ryazanov --- drivers/net/wwan/mhi_wwan_ctrl.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/net/wwan/mhi_wwan_ctrl.c b/drivers/net/wwan/mhi_wwan_ctrl.c index 1e18420..d0a98f3 100644 --- a/drivers/net/wwan/mhi_wwan_ctrl.c +++ b/drivers/net/wwan/mhi_wwan_ctrl.c @@ -41,14 +41,14 @@ struct mhi_wwan_dev { /* Increment RX budget and schedule RX refill if necessary */ static void mhi_wwan_rx_budget_inc(struct mhi_wwan_dev *mhiwwan) { - spin_lock(&mhiwwan->rx_lock); + spin_lock_bh(&mhiwwan->rx_lock); mhiwwan->rx_budget++; if (test_bit(MHI_WWAN_RX_REFILL, &mhiwwan->flags)) schedule_work(&mhiwwan->rx_refill); - spin_unlock(&mhiwwan->rx_lock); + spin_unlock_bh(&mhiwwan->rx_lock); } /* Decrement RX budget if non-zero and return true on success */ @@ -56,7 +56,7 @@ static bool mhi_wwan_rx_budget_dec(struct mhi_wwan_dev *mhiwwan) { bool ret = false; - spin_lock(&mhiwwan->rx_lock); + spin_lock_bh(&mhiwwan->rx_lock); if (mhiwwan->rx_budget) { mhiwwan->rx_budget--; @@ -64,7 +64,7 @@ static bool mhi_wwan_rx_budget_dec(struct mhi_wwan_dev *mhiwwan) ret = true; } - spin_unlock(&mhiwwan->rx_lock); + spin_unlock_bh(&mhiwwan->rx_lock); return ret; } @@ -130,9 +130,9 @@ static void mhi_wwan_ctrl_stop(struct wwan_port *port) { struct mhi_wwan_dev *mhiwwan = wwan_port_get_drvdata(port); - spin_lock(&mhiwwan->rx_lock); + spin_lock_bh(&mhiwwan->rx_lock); clear_bit(MHI_WWAN_RX_REFILL, &mhiwwan->flags); - spin_unlock(&mhiwwan->rx_lock); + spin_unlock_bh(&mhiwwan->rx_lock); cancel_work_sync(&mhiwwan->rx_refill);