From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794063695; b=OWpD2DT2ibYh5Iig8ttHfKUAow6q7y9JfRkaMjMMz2PPsvjmXgg5QsBm3SdT/uqnIfJK uVPoxj7GmH2zQTKEr0Wrp+CznBoF5tOegDSI6WN+xuDNHb9An6xue15IYoY5yk/y3PyIh IeRbmoh5G9dhwHdlkezll83fvyJZ2/tTLHXGUQAKkdnTK1t27eeqcu+e5XHnJwtgOVtPa Ope8rDjKjIBlR/MJDJLGWeQr+dNaMYlfLD+0gFBpyqFQTOj/Hr/NtWOccFgiGPXx1iqiF SQOMfSQhVcl5LMJdxqDQV0/lALb+g6fN9rvy2yX33OLcn3I5FCRskZY0m1VoHcS+BHQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063695; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=Qxb86AznLVPc+ISUgJe+2TCczz1N9SyhMXwbeWUNvJo=; b=ZB6m1/BBQ8BXavaqN8p0BI+pahetXMP1eWaq2F1xc9L/A14ILtIHJraH7y5VXrry+cKj u7fsHbaHOcMCeR3fd40RO9yOOblphR+GwcWdxllsGgilXzQp/DOXS7cjMUsyyk7YRiIFO 8MNywiFUZ+nXwAur4orEIDVGRuk8p79sW/U9Int9hj6dVJJ6B+zj1WlGxEYlshrb2G7+f yWM+H8GYOqlewnx0wXj+LvpJoFcIhBRnLljSB+DKrfMAc4m7JODSoFB1u38yN7V3yv1/f 7FGxDL1eg2BrHIqsEE4+f2RqAJZLcbxAy0kke9QwqdaSZjQ/h+XrWhp5d2uffKBTjPQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=r2kVzJuz; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5820D606A32C; Sat, 7 Nov 2026 15:01:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=r2kVzJuz Received: by smtp.kernel.org (Postfix) with ESMTPSA id 056FF1F0089F; Sat, 7 Nov 2026 15:01:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063695; bh=Qxb86AznLVPc+ISUgJe+2TCczz1N9SyhMXwbeWUNvJo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=r2kVzJuzJDE9QEyfo+Ym/74c5nGzlW/VptK6zXblJEFlYflnrO+XVrEc+ey8bbUzV Y7tDNjVrdkGzzLreso9CqpJnhaOypdLgDeu52Q1EHWP2Xl1Kl12aOlX8/8gAhFN46b z8w/9Zr0Wj580BrnMZUJcyjsqnBUMUgQlG95t/SQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Maciej Fijalkowski , Paolo Abeni , Sasha Levin Subject: [PATCH 6.18 800/869] ixgbe: reserve TX timestamp after skb preparation Date: Sat, 7 Nov 2026 08:58:02 -0500 Message-ID: <20261107134919.969351897@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134852.069646174@linuxfoundation.org> References: <20261107134852.069646174@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit f75062536e2d45ee182828f0e47e0124be2fdc8d ] ixgbe_xmit_frame_ring() takes an extra skb reference with skb_get() for the pending TX timestamp before preparing the skb for transmit. Several of the following steps may need to reallocate the skb head: - ixgbe_tso() calls skb_cow_head(), which reaches pskb_expand_head() when the header is cloned (e.g. a packet tap holds a clone). - ixgbe_tx_csum() falls back to skb_checksum_help() for unsupported checksum offsets, which can call pskb_expand_head() through skb_ensure_writable(). - With DCB and a software VLAN tag, skb_cow_head() is called to rewrite the VLAN priority. pskb_expand_head() used to BUG() on shared skbs. Since commit c7d8bc3dd511 ("net: skbuff: don't BUG() on bad arguments to pskb_expand_head()") it returns -EINVAL instead, so these packets are dropped (TSO, DCB) or sent with an unfinished checksum (skb_checksum_help() errors are ignored by ixgbe_tx_csum()). Reserve the TX timestamp right before ixgbe_tx_map(), after all skb preparation, as i40e and ice already do. The timestamp request remains covered on the FCoE path, and the cleanup on ixgbe_tx_map() failure is unchanged. Fixes: 891dc0821d20 ("ixgbe: Add ptp work item to poll for the Tx timestamp") Cc: stable@vger.kernel.org Signed-off-by: Eric Dumazet Reviewed-by: Maciej Fijalkowski Link: https://patch.msgid.link/20261026082035.335770-1-edumazet@kernel.org Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 40 +++++++++++-------- 1 file changed, 23 insertions(+), 17 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index f950570909ab2..75ba78a84c865 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -9426,23 +9426,6 @@ netdev_tx_t ixgbe_xmit_frame_ring(struct sk_buff *skb, } protocol = vlan_get_protocol(skb); - if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) && - adapter->ptp_clock) { - if (adapter->tstamp_config.tx_type == HWTSTAMP_TX_ON && - !test_and_set_bit_lock(__IXGBE_PTP_TX_IN_PROGRESS, - &adapter->state)) { - skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS; - tx_flags |= IXGBE_TX_FLAGS_TSTAMP; - - /* schedule check for Tx timestamp */ - adapter->ptp_tx_skb = skb_get(skb); - adapter->ptp_tx_start = jiffies; - schedule_work(&adapter->ptp_tx_work); - } else { - adapter->tx_hwtstamp_skipped++; - } - } - #ifdef CONFIG_PCI_IOV /* * Use the l2switch_enable flag - would be false if the DMA @@ -9507,6 +9490,29 @@ netdev_tx_t ixgbe_xmit_frame_ring(struct sk_buff *skb, #ifdef IXGBE_FCOE xmit_fcoe: #endif /* IXGBE_FCOE */ + /* Reserve the Tx timestamp only after all skb preparation: + * skb_get() makes the skb shared, and pskb_expand_head() + * (reached from skb_cow_head() or skb_checksum_help()) + * refuses shared skbs. + */ + if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) && + adapter->ptp_clock) { + if (adapter->tstamp_config.tx_type == HWTSTAMP_TX_ON && + !test_and_set_bit_lock(__IXGBE_PTP_TX_IN_PROGRESS, + &adapter->state)) { + skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS; + tx_flags |= IXGBE_TX_FLAGS_TSTAMP; + first->tx_flags |= IXGBE_TX_FLAGS_TSTAMP; + + /* schedule check for Tx timestamp */ + adapter->ptp_tx_skb = skb_get(skb); + adapter->ptp_tx_start = jiffies; + schedule_work(&adapter->ptp_tx_work); + } else { + adapter->tx_hwtstamp_skipped++; + } + } + if (ixgbe_tx_map(tx_ring, first, hdr_len)) goto cleanup_tx_timestamp; -- 2.53.0