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 D864F1DF72C; Fri, 9 Jan 2026 12:43:31 +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=1767962611; cv=none; b=NYQrFo+vCN1I/ISZof3z/t7UyrbQX8jHycsC541/rqaIVg8r84+aqM7QTAewZ7yhrRIvVf//rLEDEgCg1Vm1vr7Y+Enx4v83oJJK1xC34BqzjYvpg4Ijq5m7UxdTcwbebSkRyjC0C9XlhxyyAU5bhoznR3FhmBzdDY2GJY4SE9w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767962611; c=relaxed/simple; bh=1xlBsNlDdNlEorKNWM5a8YekZjPdD1+ktW8NuMs86ks=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=boXmDSkCJaaNRYiADtzPx/X+t3wLK58LZmddXYSDeFZbDrbrk+vCj2u0JYHruaCoV/Ryr+zgQrogskDqSlxEuhPc/iaN4HtT3pl0yInmbIKdvSBr2jRE3n5RmibRJcxL/0O1kiVHhXuQO8WhT5hAFVrLIviFsPbkfFpmfBiXxvk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=u+J94adZ; 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="u+J94adZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63195C4CEF1; Fri, 9 Jan 2026 12:43:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1767962611; bh=1xlBsNlDdNlEorKNWM5a8YekZjPdD1+ktW8NuMs86ks=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=u+J94adZx2sawHL+c6CSTgUMvPGfVakfUxQvYLNP3U5EimLMFacVPQoKG/Y/QUM9G ON4jWqGGq4rIdEvAE49gGRykuN/UG345k4fT8zz0TEnBCtI83OAgQ+2VtOqqMLTjxT ssOg/NCLHB6oHr3sUNrZoTFLzTsqIrgGnQfWsdAc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wei Fang , Hariprasad Kelam , Paolo Abeni , Sasha Levin Subject: [PATCH 6.1 427/634] net: stmmac: fix the crash issue for zero copy XDP_TX action Date: Fri, 9 Jan 2026 12:41:45 +0100 Message-ID: <20260109112133.611912933@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260109112117.407257400@linuxfoundation.org> References: <20260109112117.407257400@linuxfoundation.org> User-Agent: quilt/0.69 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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wei Fang [ Upstream commit a48e232210009be50591fdea8ba7c07b0f566a13 ] There is a crash issue when running zero copy XDP_TX action, the crash log is shown below. [ 216.122464] Unable to handle kernel paging request at virtual address fffeffff80000000 [ 216.187524] Internal error: Oops: 0000000096000144 [#1] SMP [ 216.301694] Call trace: [ 216.304130] dcache_clean_poc+0x20/0x38 (P) [ 216.308308] __dma_sync_single_for_device+0x1bc/0x1e0 [ 216.313351] stmmac_xdp_xmit_xdpf+0x354/0x400 [ 216.317701] __stmmac_xdp_run_prog+0x164/0x368 [ 216.322139] stmmac_napi_poll_rxtx+0xba8/0xf00 [ 216.326576] __napi_poll+0x40/0x218 [ 216.408054] Kernel panic - not syncing: Oops: Fatal exception in interrupt For XDP_TX action, the xdp_buff is converted to xdp_frame by xdp_convert_buff_to_frame(). The memory type of the resulting xdp_frame depends on the memory type of the xdp_buff. For page pool based xdp_buff it produces xdp_frame with memory type MEM_TYPE_PAGE_POOL. For zero copy XSK pool based xdp_buff it produces xdp_frame with memory type MEM_TYPE_PAGE_ORDER0. However, stmmac_xdp_xmit_back() does not check the memory type and always uses the page pool type, this leads to invalid mappings and causes the crash. Therefore, check the xdp_buff memory type in stmmac_xdp_xmit_back() to fix this issue. Fixes: bba2556efad6 ("net: stmmac: Enable RX via AF_XDP zero-copy") Signed-off-by: Wei Fang Reviewed-by: Hariprasad Kelam Link: https://patch.msgid.link/20251204071332.1907111-1-wei.fang@nxp.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index b2362e107f20..438d0b7da345 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -86,6 +86,7 @@ MODULE_PARM_DESC(phyaddr, "Physical device address"); #define STMMAC_XDP_CONSUMED BIT(0) #define STMMAC_XDP_TX BIT(1) #define STMMAC_XDP_REDIRECT BIT(2) +#define STMMAC_XSK_CONSUMED BIT(3) static int flow_ctrl = FLOW_AUTO; module_param(flow_ctrl, int, 0644); @@ -4839,6 +4840,7 @@ static int stmmac_xdp_get_tx_queue(struct stmmac_priv *priv, static int stmmac_xdp_xmit_back(struct stmmac_priv *priv, struct xdp_buff *xdp) { + bool zc = !!(xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL); struct xdp_frame *xdpf = xdp_convert_buff_to_frame(xdp); int cpu = smp_processor_id(); struct netdev_queue *nq; @@ -4855,9 +4857,18 @@ static int stmmac_xdp_xmit_back(struct stmmac_priv *priv, /* Avoids TX time-out as we are sharing with slow path */ txq_trans_cond_update(nq); - res = stmmac_xdp_xmit_xdpf(priv, queue, xdpf, false); - if (res == STMMAC_XDP_TX) + /* For zero copy XDP_TX action, dma_map is true */ + res = stmmac_xdp_xmit_xdpf(priv, queue, xdpf, zc); + if (res == STMMAC_XDP_TX) { stmmac_flush_tx_descriptors(priv, queue); + } else if (res == STMMAC_XDP_CONSUMED && zc) { + /* xdp has been freed by xdp_convert_buff_to_frame(), + * no need to call xsk_buff_free() again, so return + * STMMAC_XSK_CONSUMED. + */ + res = STMMAC_XSK_CONSUMED; + xdp_return_frame(xdpf); + } __netif_tx_unlock(nq); @@ -5188,6 +5199,8 @@ static int stmmac_rx_zc(struct stmmac_priv *priv, int limit, u32 queue) break; case STMMAC_XDP_CONSUMED: xsk_buff_free(buf->xdp); + fallthrough; + case STMMAC_XSK_CONSUMED: rx_dropped++; break; case STMMAC_XDP_TX: -- 2.51.0