From patchwork Wed Jun 4 14:34:53 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 894410 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 33794290D97; Wed, 4 Jun 2025 14:36:11 +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=1749047772; cv=none; b=HVkBAoti+kR/WxIRO+fggV/BJETn07QdoGanFYAmZDIkKa8Nk2wRCjYrLCVT3QCIjrIYNo7VxJMZwaOQ4XAlOXBBPXT/tisxU42Fk3VsHBTbZSdAppwxSwi2FWPPM+0ZVqd4Z/sIoFfOwF/ozq75rVCID+EA7eH/btGRWD+UsFQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749047772; c=relaxed/simple; bh=Gd8bNH4eeleNqcHxXwFWJ/GaXC03Dj2GFIogXH8ZkaU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VqPDqzntr6f/Pd1Y6xv0M2v0gvHMfoaaS3u4RaYEYCOhIuqfge6SVdjZr5GY9MGjSiid+Piidei1SM9BksoRrz1gL5KL9jXj1qQPjWHFvRjDwYVeAysIe79anyJp7SMAujZqBGNhNukicW2/GOAV3TksNqDZ/6jdGN+diiDpsYM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=j00OG5J5; 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="j00OG5J5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1301C4CEF1; Wed, 4 Jun 2025 14:36:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749047771; bh=Gd8bNH4eeleNqcHxXwFWJ/GaXC03Dj2GFIogXH8ZkaU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j00OG5J5HF4kj/561Bz1sf5az8cyRrRHdNZ43EQB0S/0LcALd9ZRMd0C/yt1skJVm yuuX7WEfkV65KZ+RRzSy0PTG7S4hLHxbOsLhctKlqa18SADU1yfr0CF0aSICdYMsvP rMVKTufQESH3r5OmHxq6ee1MY/3dIxUTpJB7MKZMJz2vlXAVuXNW6hfcnIQapyT9x8 GzoJs1v/B0UztuE+cNRpDISfg3lawMCIrIUrXrBNJgfJFL22df03IXij4qMk9H7s4k x08mWS4hoE0mDCc6oMRqYvUDjVCRq9TI1Q4MvBcNLyAH9eH5rwOHy5mqLqLZHpr0ym 2hwiWSPeS4pkw== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1uMpDt-000000006nI-2OJP; Wed, 04 Jun 2025 16:36:09 +0200 From: Johan Hovold To: Jeff Johnson Cc: Miaoqing Pan , Baochen Qiang , linux-wireless@vger.kernel.org, ath11k@lists.infradead.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH v2 1/5] wifi: ath11k: fix dest ring-buffer corruption Date: Wed, 4 Jun 2025 16:34:53 +0200 Message-ID: <20250604143457.26032-2-johan+linaro@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250604143457.26032-1-johan+linaro@kernel.org> References: <20250604143457.26032-1-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 ath11k_hal_srng_access_begin() helper for symmetry with follow-on fixes for source ring buffer corruption which will add barriers to ath11k_hal_srng_access_end(). Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41 Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices") Cc: stable@vger.kernel.org # 5.6 Signed-off-by: Johan Hovold --- drivers/net/wireless/ath/ath11k/ce.c | 3 --- drivers/net/wireless/ath/ath11k/dp_rx.c | 3 --- drivers/net/wireless/ath/ath11k/hal.c | 12 +++++++++++- 3 files changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/net/wireless/ath/ath11k/ce.c b/drivers/net/wireless/ath/ath11k/ce.c index 9d8efec46508..39d9aad33bc6 100644 --- a/drivers/net/wireless/ath/ath11k/ce.c +++ b/drivers/net/wireless/ath/ath11k/ce.c @@ -393,9 +393,6 @@ static int ath11k_ce_completed_recv_next(struct ath11k_ce_pipe *pipe, goto err; } - /* Make sure descriptor is read after the head pointer. */ - dma_rmb(); - *nbytes = ath11k_hal_ce_dst_status_get_length(desc); *skb = pipe->dest_ring->skb[sw_index]; diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c index ea2959305dec..d8dab182a9af 100644 --- a/drivers/net/wireless/ath/ath11k/dp_rx.c +++ b/drivers/net/wireless/ath/ath11k/dp_rx.c @@ -2650,9 +2650,6 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, try_again: ath11k_hal_srng_access_begin(ab, srng); - /* Make sure descriptor is read after the head pointer. */ - dma_rmb(); - while (likely(desc = (struct hal_reo_dest_ring *)ath11k_hal_srng_dst_get_next_entry(ab, srng))) { diff --git a/drivers/net/wireless/ath/ath11k/hal.c b/drivers/net/wireless/ath/ath11k/hal.c index 8cb1505a5a0c..921114686ba3 100644 --- a/drivers/net/wireless/ath/ath11k/hal.c +++ b/drivers/net/wireless/ath/ath11k/hal.c @@ -823,13 +823,23 @@ u32 *ath11k_hal_srng_src_peek(struct ath11k_base *ab, struct hal_srng *srng) void ath11k_hal_srng_access_begin(struct ath11k_base *ab, struct hal_srng *srng) { + u32 hp; + lockdep_assert_held(&srng->lock); 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); + 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(); + } /* Try to prefetch the next descriptor in the ring */ if (srng->flags & HAL_SRNG_FLAGS_CACHED)