From patchwork Tue Jun 17 08:43:59 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 897516 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 89DB528FFE5; Tue, 17 Jun 2025 08:44:50 +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=1750149890; cv=none; b=Z4IBZD0ueJeaco9ph7Wfdbr9yUy1ZWLJTeP61eiQeJ+kpzx2gJrLC1da2zPsPA52HZ+H4UJp7NkXmAn/HoqGF9tacYOpvrGEkJyYuZMRdABkUJ+bVwEXrNAlkm29UJj7JyMdvpiavAZVmGQ6PkaLB88pb7U1kPoV9lL6O5HYR9U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750149890; c=relaxed/simple; bh=SvXAxL/4I1X7cvYUjcC80e7Q09OqTbdWtCdJhyx3ICY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YvK5CPwJ71K46anFTi3rb7sDUpgnmg/8mtoFat/UqheYUM1Ksw+7TVHCOcNVmNUkuxFvrWLlhJ09xsCjP9XX+DxV+2H8R5cmKiBVYV9ZQD1EXOI0xC+70T2R+hkll8TtNc9tW64C8t5s+symknefBheN2SnL60xgF7sasjucMDg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dA0zexcY; 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="dA0zexcY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2ECCDC4CEF0; Tue, 17 Jun 2025 08:44:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750149890; bh=SvXAxL/4I1X7cvYUjcC80e7Q09OqTbdWtCdJhyx3ICY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dA0zexcYVRjaBlixv11jjYTmBY8aLGf3clA5ljYPzD+L3DcSBUaP7lQz2Ca/MhVix 2+G/ZxLKUORNOMolJYDGVKGnT4e1hJu3FC/uU7w2YLWZHA7wtH+MQZwYOeqdpj6G7m 4duIoBHbcJf4QCzl8eotBjZoqwuzWYleB0FjaLrgqgcDqI83v5AgGuBgXeFPfVekjy teUc3s3VuurpvINNr9XvLrhnncH2TRbIHahqSXqpiVnks0dfXB4sKK5OFJo3A1DLn2 lCoR/CaVan3pgKyHJxLZuqJs2KkFg88MDRzR44bPocGt651Nl0pC7yo5WuqjPRkxF1 t+rfCizdHCpJg== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1uRRw0-000000003mn-0BRJ; Tue, 17 Jun 2025 10:44:48 +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 v3 1/4] wifi: ath12k: fix dest ring-buffer corruption Date: Tue, 17 Jun 2025 10:43:59 +0200 Message-ID: <20250617084402.14475-2-johan+linaro@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617084402.14475-1-johan+linaro@kernel.org> References: <20250617084402.14475-1-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(). 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 3f3439262cf4..f7c15b547504 100644 --- a/drivers/net/wireless/ath/ath12k/ce.c +++ b/drivers/net/wireless/ath/ath12k/ce.c @@ -433,9 +433,6 @@ 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 a301898e5849..f8bd3837b9dc 100644 --- a/drivers/net/wireless/ath/ath12k/hal.c +++ b/drivers/net/wireless/ath/ath12k/hal.c @@ -2143,13 +2143,24 @@ 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()