From patchwork Wed Jun 4 14:45:06 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 894407 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 5DFDF32C85; Wed, 4 Jun 2025 14:45:49 +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=1749048349; cv=none; b=T03IIDVE1Pd1yhydhlCSWGJI9J5mnl5UcQe/YhAqcAYFnV7DnjtOEaG3Yz0Dh9iS6nmYePx5AJ15X/VVNQPtvqKI3yjCvpK0r5J1/M8Y+gBGNBt4f9QVXw8q4AyX3dR4wHKQtOKPfsQutHrC45zZoWZlQki7i/CSeJUXLMnMfNk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749048349; c=relaxed/simple; bh=AahTbiL0j1lHqgp6tMq8JeHQ5K8h8e6zfnJJYbWsUc0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fcEMHvQ5TgjxBkZhS/41HSjePhOpBYtZ66UgPhso+GvDvmcVl7YaEIW1GBetKLXz9Wn9PdQsnuf4kaID6vOzW2b2rUwcvoUBBE4L89+7v1vwJWM0XcWuxNwZNlfQpvXbRXrG35D69oYa93HXFVG8uQaj7dGtivTMm2+fpKQrzc8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bHv8Tzxa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bHv8Tzxa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E2ABC4CEF1; Wed, 4 Jun 2025 14:45:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749048349; bh=AahTbiL0j1lHqgp6tMq8JeHQ5K8h8e6zfnJJYbWsUc0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bHv8TzxaZHukiEWdht1QcuRlHO9xmK/M+5GLLPyEstC2Ehyn++Usz8tx2FV+mpjG2 pXjvObsHHKorU8W6CbN1kGvZUi1Z+7Ca+bqSJQBBF+ZuvwwgexQhA9wi/zoSn1Fq8l Nw12m1EGo6aFwPdBtLI7LaAiPafjAgw6ihZo38dYkyH4aI3JjO2cseTSyDE3vujzBY nK+s0LzaLKlEmdqBPKpsGp+8sgySANx3/FEhDOmslVL6MLYTR78ymUNI6IA57rTDXs 0sGtzvH5Ih1CroG5x+HEZUu5peIjVsE7P/i0C8XXeREs/rGW5etxoFbTHOdXkwNyWy VRqWXddF2Qbbg== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1uMpND-000000007OY-0oJh; Wed, 04 Jun 2025 16:45:47 +0200 From: Johan Hovold To: Jeff Johnson Cc: Miaoqing Pan , Remi Pommarel , Baochen Qiang , linux-wireless@vger.kernel.org, ath12k@lists.infradead.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH v2 1/4] wifi: ath12k: fix dest ring-buffer corruption Date: Wed, 4 Jun 2025 16:45:06 +0200 Message-ID: <20250604144509.28374-2-johan+linaro@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250604144509.28374-1-johan+linaro@kernel.org> References: <20250604144509.28374-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add the missing memory barrier to make sure that destination ring descriptors are read after the head pointers to avoid using stale data on weakly ordered architectures like aarch64. The barrier is added to the ath12k_hal_srng_access_begin() helper for symmetry with follow-on fixes for source ring buffer corruption which will add barriers to ath12k_hal_srng_access_end(). Note that this may fix the empty descriptor issue recently worked around by commit 51ad34a47e9f ("wifi: ath12k: Add drop descriptor handling for monitor ring"). Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Cc: stable@vger.kernel.org # 6.3 Signed-off-by: Johan Hovold --- drivers/net/wireless/ath/ath12k/ce.c | 3 --- drivers/net/wireless/ath/ath12k/hal.c | 17 ++++++++++++++--- 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/ath/ath12k/ce.c b/drivers/net/wireless/ath/ath12k/ce.c index 740586fe49d1..b66d23d6b2bd 100644 --- a/drivers/net/wireless/ath/ath12k/ce.c +++ b/drivers/net/wireless/ath/ath12k/ce.c @@ -343,9 +343,6 @@ static int ath12k_ce_completed_recv_next(struct ath12k_ce_pipe *pipe, goto err; } - /* Make sure descriptor is read after the head pointer. */ - dma_rmb(); - *nbytes = ath12k_hal_ce_dst_status_get_length(desc); *skb = pipe->dest_ring->skb[sw_index]; diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c index 91d5126ca149..9eea13ed5565 100644 --- a/drivers/net/wireless/ath/ath12k/hal.c +++ b/drivers/net/wireless/ath/ath12k/hal.c @@ -2126,13 +2126,24 @@ void *ath12k_hal_srng_src_get_next_reaped(struct ath12k_base *ab, void ath12k_hal_srng_access_begin(struct ath12k_base *ab, struct hal_srng *srng) { + u32 hp; + lockdep_assert_held(&srng->lock); - if (srng->ring_dir == HAL_SRNG_DIR_SRC) + if (srng->ring_dir == HAL_SRNG_DIR_SRC) { srng->u.src_ring.cached_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; - else - srng->u.dst_ring.cached_hp = READ_ONCE(*srng->u.dst_ring.hp_addr); + } else { + hp = READ_ONCE(*srng->u.dst_ring.hp_addr); + + if (hp != srng->u.dst_ring.cached_hp) { + srng->u.dst_ring.cached_hp = hp; + /* Make sure descriptor is read after the head + * pointer. + */ + dma_rmb(); + } + } } /* Update cached ring head/tail pointers to HW. ath12k_hal_srng_access_begin() From patchwork Wed Jun 4 14:45:07 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 894406 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 8177228F51B; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="lPpZExvU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CC2FC4AF09; Wed, 4 Jun 2025 14:45:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749048349; bh=y9HygGfhYvQ4+bq3qESNXQX/H9b1zgxy9prCNKq4TX4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lPpZExvUaF9XWORXR5+H4kYbKMlp+Y50XA50lzLec3PlOtXC82GB9RDeYBgpvzW95 djGdlXdHZNz1qHAkRPmLpKSjbfegSpqZUdzytcZFQBiFERWt/rl+N7D8ziivuqpuZm mWigyDPy7k1Kt5eIdvobRbb0o8V9wBeI/JFGgYQjfkUekVtGJS2pMMtMz/FGdG+f/j qidmwuHJXXXQe5sRXyXQ/FX0u/3dCgUva2EIliy3FdYgaR7xMBR42BMlfi4fFXsjC5 W95dApUrxlqtIWHi6h3oJo1qVYs9nibizMWPjH2z1SWxBgchzNunZs6/kdMeSRL3qC 8EPZUv1AK1itA== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1uMpND-000000007Oa-1Apm; Wed, 04 Jun 2025 16:45:47 +0200 From: Johan Hovold To: Jeff Johnson Cc: Miaoqing Pan , Remi Pommarel , Baochen Qiang , linux-wireless@vger.kernel.org, ath12k@lists.infradead.org, linux-kernel@vger.kernel.org, Johan Hovold Subject: [PATCH v2 2/4] wifi: ath12k: use plain access for descriptor length Date: Wed, 4 Jun 2025 16:45:07 +0200 Message-ID: <20250604144509.28374-3-johan+linaro@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250604144509.28374-1-johan+linaro@kernel.org> References: <20250604144509.28374-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The read memory barrier added by commit 6b67d2cf14ea ("wifi: ath12k: fix ring-buffer corruption") is enough to guarantee ordering also for plain descriptor accesses if the length helper is ever inlined so drop the unnecessary READ_ONCE(). Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 Signed-off-by: Johan Hovold --- drivers/net/wireless/ath/ath12k/hal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c index 9eea13ed5565..8615578bb802 100644 --- a/drivers/net/wireless/ath/ath12k/hal.c +++ b/drivers/net/wireless/ath/ath12k/hal.c @@ -1962,7 +1962,7 @@ u32 ath12k_hal_ce_dst_status_get_length(struct hal_ce_srng_dst_status_desc *desc { u32 len; - len = le32_get_bits(READ_ONCE(desc->flags), HAL_CE_DST_STATUS_DESC_FLAGS_LEN); + len = le32_get_bits(desc->flags, HAL_CE_DST_STATUS_DESC_FLAGS_LEN); desc->flags &= ~cpu_to_le32(HAL_CE_DST_STATUS_DESC_FLAGS_LEN); return len; From patchwork Wed Jun 4 14:45:08 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 894161 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 7752F28ECF0; Wed, 4 Jun 2025 14:45:49 +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=1749048349; cv=none; b=Gy25B95cz44VH/YZOPS0iL6e5S0dlJuuAYm6Gs1noT2dFkcq8hWQh0h2Xo7RHvxBBfDe6cWYTyqk5ad5ZyY1BiVtHbMrI1FLXqXFT1SdLwZRgbRVnNHaL2L7M4vYgQzs2w+GRjbu0Z9KBmp1gp1PI7WPCCb0ZBdMWoqOZw7jNW8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749048349; c=relaxed/simple; bh=BgxRJHC6oF+kTQhHO5k63lZHrNXK0+LyXcoaTmPrZAw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DClt9UkFyOfdhwZvsWTHua1P+MmFlFXo+SPaitcQxfm3ym7d3aUtJ6pk3W5Fe8bMEXnRbZlxHFjwg+iaknrK7zRNnyWOP4rf190XB0cpNdXcH79e1XoOICaXd6IN3sXNErhB2M46/L9VlkyRhztZo+WFtMqv4gob0iLLcAHy4aU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ilomGt0v; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ilomGt0v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36462C4AF0B; Wed, 4 Jun 2025 14:45:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749048349; bh=BgxRJHC6oF+kTQhHO5k63lZHrNXK0+LyXcoaTmPrZAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ilomGt0vO7G0ZKfNt9shwPqg1z2eu3gj4KxKipyJrApnoMZAXv8SbnhdgQisKqfDV 4eI2vhV8dwVK8/7vx5GcikdI4DFHVV9wHsca+7pypVYjXQ7jqXVDLHjK0mRJ6noK+B p8Mg5/eT4uc3Xvxeq24S8rvwdBgn1OGRUzi2ldq4ILg+ZztsvrIvz42FQCDQM+mHG7 QQUSixi7xWA8KfhS0c/lP6vjmaJOyApxOtZFGkO7lQAWN9hIEP7lJzagKMopW/wYjQ ripE/n4T/QHD2yFpDvkBN4fjedDsilTX6dOpRy/wqmJBzqjl4EzsEFfqFmMt89pPvw EnmGNbvtXumNw== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1uMpND-000000007Od-1Vqg; Wed, 04 Jun 2025 16:45:47 +0200 From: Johan Hovold To: Jeff Johnson Cc: Miaoqing Pan , Remi Pommarel , Baochen Qiang , linux-wireless@vger.kernel.org, ath12k@lists.infradead.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH v2 3/4] wifi: ath12k: fix source ring-buffer corruption Date: Wed, 4 Jun 2025 16:45:08 +0200 Message-ID: <20250604144509.28374-4-johan+linaro@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250604144509.28374-1-johan+linaro@kernel.org> References: <20250604144509.28374-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add the missing memory barrier to make sure that LMAC source ring descriptors are written before updating the head pointer to avoid passing stale data to the firmware on weakly ordered architectures like aarch64. Note that non-LMAC rings use MMIO write accessors which have the required write memory barrier. Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Cc: stable@vger.kernel.org # 6.3 Signed-off-by: Johan Hovold --- drivers/net/wireless/ath/ath12k/hal.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c index 8615578bb802..1e2d13cc2d19 100644 --- a/drivers/net/wireless/ath/ath12k/hal.c +++ b/drivers/net/wireless/ath/ath12k/hal.c @@ -2161,7 +2161,11 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng) if (srng->ring_dir == HAL_SRNG_DIR_SRC) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; - *srng->u.src_ring.hp_addr = srng->u.src_ring.hp; + /* Make sure descriptor is written before updating the + * head pointer. + */ + dma_wmb(); + WRITE_ONCE(*srng->u.src_ring.hp_addr, srng->u.src_ring.hp); } else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; *srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp; @@ -2170,6 +2174,10 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng) if (srng->ring_dir == HAL_SRNG_DIR_SRC) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; + /* Assume implementation use an MMIO write accessor + * which has the required wmb() so that the descriptor + * is written before the updating the head pointer. + */ ath12k_hif_write32(ab, (unsigned long)srng->u.src_ring.hp_addr - (unsigned long)ab->mem, From patchwork Wed Jun 4 14:45:09 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 894405 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 C1FD529186E; Wed, 4 Jun 2025 14:45:49 +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=1749048349; cv=none; b=VSCdfsVtOgtcWJfpwedXX1mkRFf6/D8PUaV++nCva93RmLW91MgFFFz4ByopT1TnW7nB0Z6McJr/EhqEwrv3DO8S0G7/LAM/oGFSDfdWZBY421UmMBxdlqehyxOQFehsYTaPJ4KSgxD03+nZGRU2MfWB7uNko8EmpQbHaTPfUvk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749048349; c=relaxed/simple; bh=w++DUul6WcS0rSeeNY1gMqZO7ksu6qS8oACYN9qdE9g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JwiYjGMqfFCHi9ypkQnQEcpaLO4yXnA5RhPRpwLlHzwHY7erut5oVt8hG+HF6WQbeKXpbv0JNgGbpgpvQq8UwqF/7kXxPMrDA3WDsmpjDXgxX2zSqF/PQNow2ltBGqqh7xzAKWqAAgFfj+Tz5C/MQtQmjlaaG/xlmnQLJwY7yrg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IkrLm8Ky; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IkrLm8Ky" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5051CC4CEF2; Wed, 4 Jun 2025 14:45:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749048349; bh=w++DUul6WcS0rSeeNY1gMqZO7ksu6qS8oACYN9qdE9g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IkrLm8KyEgBIdcnPkUh6cZBTFEjtbBHQX++sOEqB/pzXthf3AHJqb/zAXTT8E/Lgd pI8TfaFYm3T8ElVMgZ+DWjX87LuF0790VA9kIVn3+e8RtTP4zIl0jtjkd03W5jWIEB ikt5zblFvelL8rd8/sBkuOitWX/M4BN5nLHA5Z8y3ep1RKTiG3GihM54cF/6FSdpRG ugPZbiMhztgLJJnqY6WlD2rimfEAQqGwDOpQk3ucXncIcrtprdkqFaeLQwi9a4Z0Q5 zBiyfpShGcoreRT+lkGwjIkn6gGTZ2Ila/eL8apzfzrsZWmsO7AojJMPd0KTyUf6l9 6071CGX5zPpLw== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1uMpND-000000007Of-1tJZ; Wed, 04 Jun 2025 16:45:47 +0200 From: Johan Hovold To: Jeff Johnson Cc: Miaoqing Pan , Remi Pommarel , Baochen Qiang , linux-wireless@vger.kernel.org, ath12k@lists.infradead.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH v2 4/4] wifi: ath12k: fix dest ring-buffer corruption when ring is full Date: Wed, 4 Jun 2025 16:45:09 +0200 Message-ID: <20250604144509.28374-5-johan+linaro@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250604144509.28374-1-johan+linaro@kernel.org> References: <20250604144509.28374-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add the missing memory barriers to make sure that destination ring descriptors are read before updating the tail pointer (and passing ownership to the device) to avoid memory corruption on weakly ordered architectures like aarch64 when the ring is full. Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Cc: stable@vger.kernel.org # 6.3 Signed-off-by: Johan Hovold --- drivers/net/wireless/ath/ath12k/hal.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c index 1e2d13cc2d19..4da354e86a75 100644 --- a/drivers/net/wireless/ath/ath12k/hal.c +++ b/drivers/net/wireless/ath/ath12k/hal.c @@ -2153,7 +2153,6 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng) { lockdep_assert_held(&srng->lock); - /* TODO: See if we need a write memory barrier here */ if (srng->flags & HAL_SRNG_FLAGS_LMAC_RING) { /* For LMAC rings, ring pointer updates are done through FW and * hence written to a shared memory location that is read by FW @@ -2168,7 +2167,11 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng) WRITE_ONCE(*srng->u.src_ring.hp_addr, srng->u.src_ring.hp); } else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; - *srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp; + /* Make sure descriptor is read before updating the + * tail pointer. + */ + dma_mb(); + WRITE_ONCE(*srng->u.dst_ring.tp_addr, srng->u.dst_ring.tp); } } else { if (srng->ring_dir == HAL_SRNG_DIR_SRC) { @@ -2184,6 +2187,10 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng) srng->u.src_ring.hp); } else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; + /* Make sure descriptor is read before updating the + * tail pointer. + */ + mb(); ath12k_hif_write32(ab, (unsigned long)srng->u.dst_ring.tp_addr - (unsigned long)ab->mem,