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 B31AD159583; Mon, 29 Jan 2024 17:10:21 +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=1706548221; cv=none; b=IlzWMWtujipvyS6W1rFYbPKKHl4c40/6AOOIyJ2T8XXttnblQNM4OV8I71PG3ajrK91sSZRPFN6//qM+mrKl6CS8H7N4UhB0cP7HtIZFIr6iPFue9AVeWD50ItPhznvBUXSZHZEFq7uTZ8VzAwJFlxuf5+6DbqcRu8tNop67uSk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706548221; c=relaxed/simple; bh=v0KrcLPEFfxaiEkK9DE5a9bE3d/LIWrpUMuaQWYCGbQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SnV63Ie/HGb6j4hRpe6G2E3G5ZSY4nM2cUYBR0uXKd5W1jervSDx9vZ9+kbvRSUF2pOFJVrMoxQ1sAJc7GWzTjS4bFy2WXOuwdc3GkyLEEb4cy2j1nmq/D61bg8I2ktxXgTGE3By0UrqWI/PnJx/7gRX8UNUkQJgTjvXE0dXRm8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Gl3f1sJD; 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="Gl3f1sJD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7836FC433C7; Mon, 29 Jan 2024 17:10:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1706548221; bh=v0KrcLPEFfxaiEkK9DE5a9bE3d/LIWrpUMuaQWYCGbQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Gl3f1sJD5T73ImLVdo2cuBLl8BeIV4e7plDaNnwdlGVwz9h6+lawPT96C9Cyjp4X9 USi+2voYEy70Eq1Uw0572YqSzJb5ayCKr55aL4IvPDPk6UBTb0qOQs0WUH1qw9RGjB XxuwsL4552cXfXSg0jEaRYrE1VDNBoOWQvyzmdIc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bhaumik Bhatt , Qiang Yu , Jeffrey Hugo , Manivannan Sadhasivam Subject: [PATCH 6.1 026/185] bus: mhi: host: Add spinlock to protect WP access when queueing TREs Date: Mon, 29 Jan 2024 09:03:46 -0800 Message-ID: <20240129165959.443249554@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240129165958.589924174@linuxfoundation.org> References: <20240129165958.589924174@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bhaumik Bhatt commit b89b6a863dd53bc70d8e52d50f9cfaef8ef5e9c9 upstream. Protect WP accesses such that multiple threads queueing buffers for incoming data do not race. Meanwhile, if CONFIG_TRACE_IRQFLAGS is enabled, irq will be enabled once __local_bh_enable_ip is called as part of write_unlock_bh. Hence, let's take irqsave lock after TRE is generated to avoid running write_unlock_bh when irqsave lock is held. Cc: stable@vger.kernel.org Fixes: 189ff97cca53 ("bus: mhi: core: Add support for data transfer") Signed-off-by: Bhaumik Bhatt Signed-off-by: Qiang Yu Reviewed-by: Jeffrey Hugo Tested-by: Jeffrey Hugo Reviewed-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/1702276972-41296-2-git-send-email-quic_qianyu@quicinc.com Signed-off-by: Manivannan Sadhasivam Signed-off-by: Greg Kroah-Hartman --- drivers/bus/mhi/host/main.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) --- a/drivers/bus/mhi/host/main.c +++ b/drivers/bus/mhi/host/main.c @@ -1124,17 +1124,15 @@ static int mhi_queue(struct mhi_device * if (unlikely(MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))) return -EIO; - read_lock_irqsave(&mhi_cntrl->pm_lock, flags); - ret = mhi_is_ring_full(mhi_cntrl, tre_ring); - if (unlikely(ret)) { - ret = -EAGAIN; - goto exit_unlock; - } + if (unlikely(ret)) + return -EAGAIN; ret = mhi_gen_tre(mhi_cntrl, mhi_chan, buf_info, mflags); if (unlikely(ret)) - goto exit_unlock; + return ret; + + read_lock_irqsave(&mhi_cntrl->pm_lock, flags); /* Packet is queued, take a usage ref to exit M3 if necessary * for host->device buffer, balanced put is done on buffer completion @@ -1154,7 +1152,6 @@ static int mhi_queue(struct mhi_device * if (dir == DMA_FROM_DEVICE) mhi_cntrl->runtime_put(mhi_cntrl); -exit_unlock: read_unlock_irqrestore(&mhi_cntrl->pm_lock, flags); return ret; @@ -1206,6 +1203,9 @@ int mhi_gen_tre(struct mhi_controller *m int eot, eob, chain, bei; int ret; + /* Protect accesses for reading and incrementing WP */ + write_lock_bh(&mhi_chan->lock); + buf_ring = &mhi_chan->buf_ring; tre_ring = &mhi_chan->tre_ring; @@ -1223,8 +1223,10 @@ int mhi_gen_tre(struct mhi_controller *m if (!info->pre_mapped) { ret = mhi_cntrl->map_single(mhi_cntrl, buf_info); - if (ret) + if (ret) { + write_unlock_bh(&mhi_chan->lock); return ret; + } } eob = !!(flags & MHI_EOB); @@ -1241,6 +1243,8 @@ int mhi_gen_tre(struct mhi_controller *m mhi_add_ring_element(mhi_cntrl, tre_ring); mhi_add_ring_element(mhi_cntrl, buf_ring); + write_unlock_bh(&mhi_chan->lock); + return 0; }