From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 929A82773F4; Tue, 21 Oct 2025 20:11:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761077497; cv=none; b=jW6Z8KbP5Le2zXRtBOn2fM82c0HFC7vyMiZqCR/TvEvVmFO1qqVYLYt2XUZX3NaLXrIBZ7/Y1oIHMODJxBUCUCbYOAiz/Ld1DDSM/fSZZsXbv/e3aQydl4496S/onamVRKkytvOOR91RZoItYr0PlQM/7Ati7oNxiCiNCVjlL9o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761077497; c=relaxed/simple; bh=DSoZoE3mCwUPkPg+d2UA/+B/whXQpF2R22NW0TGSWmA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EOUF9bbJbDUU7zDnuouRGsqrkNEK0bvzZ5x6NUTvfc34OIh0qnaYPBEnU8KDPxXHJwVK+c/G9hx4Fv7evGUOE61zatg2NV4nc4fs1Q5vhuBgfIB+i27DTDurlyoDcNPd2Kv1pJai09KDJ1AniTn8ZuwlZADYUSbBCSUxkhKvWSQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yjVQ9TU7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="yjVQ9TU7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EFFB9C4CEF7; Tue, 21 Oct 2025 20:11:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1761077497; bh=DSoZoE3mCwUPkPg+d2UA/+B/whXQpF2R22NW0TGSWmA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yjVQ9TU7OfGX6I9SH8xo2zjNC067q+bXEScHiXYLqvnpfe2z81XHkubN9Sg32NlEr R33p1FZnL1xUfq/7M6YGouecVM3yjTc+XlKyf51iRNBoybGrZUqC0rTqtFNKM8lBhm RpQRAEoaaNw20jzZgF5d3jAffbRl/vzduO++GtF8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Pranjal Ramajor Asha Kanojiya , Youssef Samir , Jeff Hugo , Carl Vanderlip , Sasha Levin Subject: [PATCH 6.17 123/159] accel/qaic: Synchronize access to DBC request queue head & tail pointer Date: Tue, 21 Oct 2025 21:51:40 +0200 Message-ID: <20251021195046.114565555@linuxfoundation.org> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20251021195043.182511864@linuxfoundation.org> References: <20251021195043.182511864@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pranjal Ramajor Asha Kanojiya [ Upstream commit 52e59f7740ba23bbb664914967df9a00208ca10c ] Two threads of the same process can potential read and write parallelly to head and tail pointers of the same DBC request queue. This could lead to a race condition and corrupt the DBC request queue. Fixes: ff13be830333 ("accel/qaic: Add datapath") Signed-off-by: Pranjal Ramajor Asha Kanojiya Signed-off-by: Youssef Samir Reviewed-by: Jeff Hugo Reviewed-by: Carl Vanderlip [jhugo: Add fixes tag] Signed-off-by: Jeff Hugo Link: https://lore.kernel.org/r/20251007061837.206132-1-youssef.abdulrahman@oss.qualcomm.com Signed-off-by: Sasha Levin --- drivers/accel/qaic/qaic.h | 2 ++ drivers/accel/qaic/qaic_data.c | 12 ++++++++++-- drivers/accel/qaic/qaic_drv.c | 3 +++ 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/accel/qaic/qaic.h b/drivers/accel/qaic/qaic.h index c31081e42cee0..820d133236dd1 100644 --- a/drivers/accel/qaic/qaic.h +++ b/drivers/accel/qaic/qaic.h @@ -97,6 +97,8 @@ struct dma_bridge_chan { * response queue's head and tail pointer of this DBC. */ void __iomem *dbc_base; + /* Synchronizes access to Request queue's head and tail pointer */ + struct mutex req_lock; /* Head of list where each node is a memory handle queued in request queue */ struct list_head xfer_list; /* Synchronizes DBC readers during cleanup */ diff --git a/drivers/accel/qaic/qaic_data.c b/drivers/accel/qaic/qaic_data.c index 797289e9d7806..c4f117edb266e 100644 --- a/drivers/accel/qaic/qaic_data.c +++ b/drivers/accel/qaic/qaic_data.c @@ -1356,13 +1356,17 @@ static int __qaic_execute_bo_ioctl(struct drm_device *dev, void *data, struct dr goto release_ch_rcu; } + ret = mutex_lock_interruptible(&dbc->req_lock); + if (ret) + goto release_ch_rcu; + head = readl(dbc->dbc_base + REQHP_OFF); tail = readl(dbc->dbc_base + REQTP_OFF); if (head == U32_MAX || tail == U32_MAX) { /* PCI link error */ ret = -ENODEV; - goto release_ch_rcu; + goto unlock_req_lock; } queue_level = head <= tail ? tail - head : dbc->nelem - (head - tail); @@ -1370,11 +1374,12 @@ static int __qaic_execute_bo_ioctl(struct drm_device *dev, void *data, struct dr ret = send_bo_list_to_device(qdev, file_priv, exec, args->hdr.count, is_partial, dbc, head, &tail); if (ret) - goto release_ch_rcu; + goto unlock_req_lock; /* Finalize commit to hardware */ submit_ts = ktime_get_ns(); writel(tail, dbc->dbc_base + REQTP_OFF); + mutex_unlock(&dbc->req_lock); update_profiling_data(file_priv, exec, args->hdr.count, is_partial, received_ts, submit_ts, queue_level); @@ -1382,6 +1387,9 @@ static int __qaic_execute_bo_ioctl(struct drm_device *dev, void *data, struct dr if (datapath_polling) schedule_work(&dbc->poll_work); +unlock_req_lock: + if (ret) + mutex_unlock(&dbc->req_lock); release_ch_rcu: srcu_read_unlock(&dbc->ch_lock, rcu_id); unlock_dev_srcu: diff --git a/drivers/accel/qaic/qaic_drv.c b/drivers/accel/qaic/qaic_drv.c index e31bcb0ecfc94..e162f4b8a262a 100644 --- a/drivers/accel/qaic/qaic_drv.c +++ b/drivers/accel/qaic/qaic_drv.c @@ -454,6 +454,9 @@ static struct qaic_device *create_qdev(struct pci_dev *pdev, return NULL; init_waitqueue_head(&qdev->dbc[i].dbc_release); INIT_LIST_HEAD(&qdev->dbc[i].bo_lists); + ret = drmm_mutex_init(drm, &qdev->dbc[i].req_lock); + if (ret) + return NULL; } return qdev; -- 2.51.0