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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 61E1FF01806 for ; Fri, 6 Mar 2026 07:25:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=fjlemuBfXmF8h4exbANL83Qw2QHTnRIeuxbf0LQ3vgg=; b=B21R301mJQYsgt gGWXrYrdqt3bkkr4jZpzWQ666pC8LcUOe+sNTmoCSfuzsy/2Jt354v2YLPTzam2PiiKIZFIS0iyfw lkYozAYukVfhUyZ3bC8furfVizYRetO8uL8ndestVUPJiT2u4PYT3lAWZMEnJw/8E/P148xcBVl+i H2qLdsFCJRopCe0DzSim3bsc2z6tluLm2VE9ucm7lx/i5XCZa5QdBgOpS+T/OQ1rK0yGLuaEHy8hn ayang/gHzV1C4l25COtwZi0hQ7TPy0PmhOfEdAiLmAL/CEN3U0rg9bkHzKhT6b6UM3trF3jDXnlPh oVvtbE9SG102UQCyFfLQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vyPYg-0000000398J-3b5l; Fri, 06 Mar 2026 07:25:14 +0000 Received: from mgamail.intel.com ([192.198.163.8]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vyPYf-0000000395H-1A2e for linux-i3c@lists.infradead.org; Fri, 06 Mar 2026 07:25:14 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1772781913; x=1804317913; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0ZKJ2GScSnamMEAgJfgAqhRME5OwF+42tWNsFg9y+X0=; b=haMqbAX9cB3N2J5hPDBMcXY7Un4UCzpAizBTLgyZtUzmnsTgQPTXV9qL 7aHq/kI3eacyS6iVuhtQxAqfREJJCt99S5EowmK60CTAZCRSkt32bo/JJ U/Atsk1yepPwTHaLaxrmNEcPO8qe8uHKyy/8H+sWOARLka24SfyvvdeYU lr0Jr9XXNki0ZUjag4TroEA2RlxYGOcyU5kaJJLymBs5iiKJYURntxlXp EN5ndtGGL0LhEUf2FRqHe4vNUAfZZs424atjxrw56+gAROiJFrPdsNOtL MB10DMNJkOjW5dIXZb+buZdido0fa7L59YTMktHmu2fe1vEycLR214plj A==; X-CSE-ConnectionGUID: OM4gRhoMS6yRnSDYyWJNhQ== X-CSE-MsgGUID: 97R1Fi0XQjSVKX0PhBb+Zg== X-IronPort-AV: E=McAfee;i="6800,10657,11720"; a="91461336" X-IronPort-AV: E=Sophos;i="6.23,104,1770624000"; d="scan'208";a="91461336" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Mar 2026 23:25:13 -0800 X-CSE-ConnectionGUID: dOct7xh2SGOqYM4PIGB/7Q== X-CSE-MsgGUID: Nbi2tx6ERYuMUAI+lXJYPw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,104,1770624000"; d="scan'208";a="223419921" Received: from dhhellew-desk2.ger.corp.intel.com (HELO ahunter6-desk) ([10.245.244.171]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Mar 2026 23:25:11 -0800 From: Adrian Hunter To: alexandre.belloni@bootlin.com Cc: Frank.Li@nxp.com, linux-i3c@lists.infradead.org Subject: [PATCH V3 06/14] i3c: mipi-i3c-hci: Fix race in DMA ring dequeue Date: Fri, 6 Mar 2026 09:24:43 +0200 Message-ID: <20260306072451.11131-7-adrian.hunter@intel.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260306072451.11131-1-adrian.hunter@intel.com> References: <20260306072451.11131-1-adrian.hunter@intel.com> MIME-Version: 1.0 Organization: Intel Finland Oy, Registered Address: c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo, Business Identity Code: 0357606 - 4, Domiciled in Helsinki X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260305_232513_327458_C125CA62 X-CRM114-Status: GOOD ( 11.17 ) X-BeenThere: linux-i3c@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-i3c" Errors-To: linux-i3c-bounces+linux-i3c=archiver.kernel.org@lists.infradead.org The HCI DMA dequeue path (hci_dma_dequeue_xfer()) may be invoked for multiple transfers that timeout around the same time. However, the function is not serialized and can race with itself. When a timeout occurs, hci_dma_dequeue_xfer() stops the ring, processes incomplete transfers, and then restarts the ring. If another timeout triggers a parallel call into the same function, the two instances may interfere with each other - stopping or restarting the ring at unexpected times. Add a mutex so that hci_dma_dequeue_xfer() is serialized with respect to itself. Fixes: 9ad9a52cce282 ("i3c/master: introduce the mipi-i3c-hci driver") Cc: stable@vger.kernel.org Signed-off-by: Adrian Hunter Reviewed-by: Frank Li --- Changes in V3: Add Frank's Rev'd-by Changes in V2: Mutex now defined in struct i3c_hci instead of struct hci_rh_data drivers/i3c/master/mipi-i3c-hci/core.c | 1 + drivers/i3c/master/mipi-i3c-hci/dma.c | 2 ++ drivers/i3c/master/mipi-i3c-hci/hci.h | 1 + 3 files changed, 4 insertions(+) diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c index faf5eae2409f..061e84a5c412 100644 --- a/drivers/i3c/master/mipi-i3c-hci/core.c +++ b/drivers/i3c/master/mipi-i3c-hci/core.c @@ -927,6 +927,7 @@ static int i3c_hci_probe(struct platform_device *pdev) return -ENOMEM; spin_lock_init(&hci->lock); + mutex_init(&hci->control_mutex); /* * Multi-bus instances share the same MMIO address range, but not diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c index 74b255ad6d0f..f7d411e5e11f 100644 --- a/drivers/i3c/master/mipi-i3c-hci/dma.c +++ b/drivers/i3c/master/mipi-i3c-hci/dma.c @@ -547,6 +547,8 @@ static bool hci_dma_dequeue_xfer(struct i3c_hci *hci, unsigned int i; bool did_unqueue = false; + guard(mutex)(&hci->control_mutex); + /* stop the ring */ rh_reg_write(RING_CONTROL, RING_CTRL_ABORT); if (wait_for_completion_timeout(&rh->op_done, HZ) == 0) { diff --git a/drivers/i3c/master/mipi-i3c-hci/hci.h b/drivers/i3c/master/mipi-i3c-hci/hci.h index f1dd502c071f..9c63d80f7fc4 100644 --- a/drivers/i3c/master/mipi-i3c-hci/hci.h +++ b/drivers/i3c/master/mipi-i3c-hci/hci.h @@ -51,6 +51,7 @@ struct i3c_hci { void *io_data; const struct hci_cmd_ops *cmd; spinlock_t lock; + struct mutex control_mutex; atomic_t next_cmd_tid; bool irq_inactive; u32 caps; -- 2.51.0 -- linux-i3c mailing list linux-i3c@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-i3c