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 378E66F062; Mon, 29 Jan 2024 17:14:17 +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=1706548457; cv=none; b=klOeP83JmL7ybOSZTaR8qoXd7cMmc+LAZ+px3S0velSC0tXgN9/HCBl08Ls2OEvBRa8Jjzm6n2lByJl2ErU5ygPJFc743Rmj3Jv2HTF2zdYUMsZRx5zqXzSxyrsM46wp5eSD09BDVmql/eIN3zI2baAfRIAdmDm4FVZUiTbF8+Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706548457; c=relaxed/simple; bh=/RVfp5prStTJF0adS/CjGVF1PJLp1AlpxJS7me7SVl4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZQelEuoL+u3gL3OiMoKCafPJ8LP/vVaCMDBx+wPtOpBOa5EO/mDOSYLvx+SLMcpkAA5HWBX1SlZzAFw+g/ClgVeAXZti15jZFhh/9hSIW0ono8gakTJN4vMv3WjPOv/l+1U+wkmwSkZj9/ALCfGTDWVNRqTCH1ScAl+OGMO+g3c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jLP9LX3i; 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="jLP9LX3i" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F26A6C433C7; Mon, 29 Jan 2024 17:14:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1706548457; bh=/RVfp5prStTJF0adS/CjGVF1PJLp1AlpxJS7me7SVl4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jLP9LX3iqMz2K18TOiR/VxeE9voQ7zyprGtujir2BwiBwrChLc4+6CBNlQJgt2e/i yCyETzHLo3l9YuFtY3Lsf3xlWJimpb2nsQj6kX9sdFStSdJC9TCfKxPNNE3cidFe8Y ADv1ICaJOoeULSEnzm45fMF1GoP1VJSMdInjWqqE= 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 6.6 069/331] bus: mhi: host: Add spinlock to protect WP access when queueing TREs Date: Mon, 29 Jan 2024 09:02:13 -0800 Message-ID: <20240129170016.945886064@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240129170014.969142961@linuxfoundation.org> References: <20240129170014.969142961@linuxfoundation.org> User-Agent: quilt/0.67 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 6.6-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 @@ -1127,17 +1127,15 @@ 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 @@ -1157,7 +1155,6 @@ 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; @@ -1209,6 +1206,9 @@ 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; @@ -1226,8 +1226,10 @@ 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); @@ -1244,6 +1246,8 @@ 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; }