From nobody Tue Apr 7 12:38:51 2026 Received: from mta-64-227.siemens.flowmailer.net (mta-64-227.siemens.flowmailer.net [185.136.64.227]) (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 27A44311954 for ; Wed, 25 Feb 2026 09:58:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.136.64.227 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772013528; cv=none; b=njtXXbM/rfK3ZocSXKX3DGVhFCCnCnIYBWxyGD9mgvXM5JObnajS0ld9jo8rfMiwlFE2ksOAdeYbYw5SsyXiz2l98ADxT4CVxi6pID+p4rG6+TzTwB0P7cRLT4/Pfb7yGRP6GU/QizBSCrxxnB9ySwByWfMXTWCy3zUzeYetJhU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772013528; c=relaxed/simple; bh=Ox0L7LirTZNfJd5VLbNpMdUA+4MnK0U5rhS/1YdWexA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=qJYI9vAJbAq+s7Lt/8Sd3QUh2A86HV8m8n3e5iX7PD53kp51GEbu3Nd9p/ois3V+joClGKWJbQ7oZCV86uE4+qSX3mheKjqX6uPzsstdwUDeRTKoq+zT9oW4yVIucSnTxvZ52TwCh8WtIQXYrjESMTmJ+FZtrPbo6w1+YxiA0Es= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=siemens.com; spf=pass smtp.mailfrom=rts-flowmailer.siemens.com; dkim=pass (2048-bit key) header.d=siemens.com header.i=zdenek.bouska@siemens.com header.b=POAQ8MaP; arc=none smtp.client-ip=185.136.64.227 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=siemens.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rts-flowmailer.siemens.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=siemens.com header.i=zdenek.bouska@siemens.com header.b="POAQ8MaP" Received: by mta-64-227.siemens.flowmailer.net with ESMTPSA id 20260225095838b465f9007400020748 for ; Wed, 25 Feb 2026 10:58:38 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm2; d=siemens.com; i=zdenek.bouska@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc; bh=vbj4RSQJDuRYZ5fTpF5eYkTEyvzPIP9uBuxY7VVzDmM=; b=POAQ8MaPlX4fuojo9+xfcFWxUf97NiISPsrBO2/DpPm093KQwl0AJglgbNtaQJzz0iIFp6 AAfPsLjNAV/eE+cPiN9/yvtya0J9mNc6iJ5qioKDKLoiR5g7yarF7s1+VCCEo147aipwwrX+ HcrlK5Qk4F9EkN6ApiPnnM4FY++3CqEznsh0cfOzSBHXah68oViZ3s45liPWlE572HgU5+yX 1CsbEiUgOOOWzfz3fLxb6sxQ+L9vFRqXJjhr3+fJQtDOrUTqUdlnML7rYV273MOF1eWSc2pR +PE0TVizaznqZI94VNSYZeneQ1VUIEGxhZCUhbsQnyZ7sPwoJZ+OIZUQ==; From: Zdenek Bouska Date: Wed, 25 Feb 2026 10:58:29 +0100 Subject: [PATCH v2] igc: fix page fault in XDP TX timestamps handling Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260225-igc-fix-xdp-tx-tstamp-pagefault-v2-1-bf797ec20f3b@siemens.com> X-B4-Tracking: v=1; b=H4sIAMTHnmkC/4WNyw6CMBBFf4XM2jF05KGu/A/DopYBJhHatJVgC P9uJe5dnpubc1YI7IUDXLMVPM8SxE4J6JCBGfTUM0qbGCinKidFKL3BThZcWodxwRiiHh063XO nX8+IptCPlovydK4IksV5Tve9cG8SDxKi9e89OKvv+nNT8dc9K1RYm5ou3FWKubwF4ZGncDR2h Gbbtg9mcT600AAAAA== X-Change-ID: 20260212-igc-fix-xdp-tx-tstamp-pagefault-c4abde453862 To: Tony Nguyen , Przemek Kitszel , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , Richard Cochran , Song Yoong Siang , Lai Peter Jun Ann Cc: Vinicius Costa Gomes , intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, Florian Bezdeka , Zdenek Bouska X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-1328595:519-21489:flowmailer If an XDP application that requested TX timestamping is shutting down while the link of the interface in use is still up the following kernel splat is reported: [ 883.803618] [ T1554] BUG: unable to handle page fault for address: fff= fcfb6200fd008 ... [ 883.803650] [ T1554] Call Trace: [ 883.803652] [ T1554] [ 883.803654] [ T1554] igc_ptp_tx_tstamp_event+0xdf/0x160 [igc] [ 883.803660] [ T1554] igc_tsync_interrupt+0x2d5/0x300 [igc] ... During shutdown of the TX ring the xsk_meta pointers are left behind, so that the IRQ handler is trying to touch them. This issue is now being fixed by cleaning up the stale xsk meta data on TX shutdown. TX timestamps on other queues remain unaffected. Fixes: 15fd021bc427 ("igc: Add Tx hardware timestamp request for AF_XDP zer= o-copy packet") Signed-off-by: Zdenek Bouska Reviewed-by: Florian Bezdeka Reviewed-by: Paul Menzel Tested-by: Avigail Dahan --- Changes in v2: - Moved 'adapter' variable declaration into the if block (Vinicius) - Link to v1: https://lore.kernel.org/r/20260224-igc-fix-xdp-tx-tstamp-page= fault-v1-1-7c729ef61ee5@siemens.com --- drivers/net/ethernet/intel/igc/igc.h | 2 ++ drivers/net/ethernet/intel/igc/igc_main.c | 7 +++++++ drivers/net/ethernet/intel/igc/igc_ptp.c | 33 +++++++++++++++++++++++++++= ++++ 3 files changed, 42 insertions(+) diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/in= tel/igc/igc.h index a427f05814c1ae7330c6f7034cd0f2b40b74dab6..17236813965d334f14eba928aff= bd4f91b96ecd4 100644 --- a/drivers/net/ethernet/intel/igc/igc.h +++ b/drivers/net/ethernet/intel/igc/igc.h @@ -781,6 +781,8 @@ int igc_ptp_hwtstamp_set(struct net_device *netdev, struct kernel_hwtstamp_config *config, struct netlink_ext_ack *extack); void igc_ptp_tx_hang(struct igc_adapter *adapter); +void igc_ptp_clear_xsk_tx_tstamp_queue(struct igc_adapter *adapter, + u16 queue_id); void igc_ptp_read(struct igc_adapter *adapter, struct timespec64 *ts); void igc_ptp_tx_tstamp_event(struct igc_adapter *adapter); =20 diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethern= et/intel/igc/igc_main.c index 89a321a344d263ace5c66f7ade782b40cc482566..1931fcb659354d5009e0ea02316= bf3a47b66b04d 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -264,6 +264,13 @@ static void igc_clean_tx_ring(struct igc_ring *tx_ring) /* reset next_to_use and next_to_clean */ tx_ring->next_to_use =3D 0; tx_ring->next_to_clean =3D 0; + + /* Clear any lingering XSK TX timestamp requests */ + if (test_bit(IGC_RING_FLAG_TX_HWTSTAMP, &tx_ring->flags)) { + struct igc_adapter *adapter =3D netdev_priv(tx_ring->netdev); + + igc_ptp_clear_xsk_tx_tstamp_queue(adapter, tx_ring->queue_index); + } } =20 /** diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/etherne= t/intel/igc/igc_ptp.c index 7aae83c108fd7611b00bf075592f93a902b83422..98491346d21b80925ce42ba276d= 851d4318e66b7 100644 --- a/drivers/net/ethernet/intel/igc/igc_ptp.c +++ b/drivers/net/ethernet/intel/igc/igc_ptp.c @@ -576,6 +576,39 @@ static void igc_ptp_clear_tx_tstamp(struct igc_adapter= *adapter) spin_unlock_irqrestore(&adapter->ptp_tx_lock, flags); } =20 +/** + * igc_ptp_clear_xsk_tx_tstamp_queue - Clear pending XSK TX timestamps for= a queue + * @adapter: Board private structure + * @queue_id: TX queue index to clear timestamps for + * + * Iterates over all TX timestamp registers and releases any pending + * timestamp requests associated with the given TX queue. This is + * called when an XDP pool is being disabled to ensure no stale + * timestamp references remain. + */ +void igc_ptp_clear_xsk_tx_tstamp_queue(struct igc_adapter *adapter, u16 qu= eue_id) +{ + unsigned long flags; + int i; + + spin_lock_irqsave(&adapter->ptp_tx_lock, flags); + + for (i =3D 0; i < IGC_MAX_TX_TSTAMP_REGS; i++) { + struct igc_tx_timestamp_request *tstamp =3D &adapter->tx_tstamp[i]; + + if (tstamp->buffer_type !=3D IGC_TX_BUFFER_TYPE_XSK) + continue; + if (tstamp->xsk_queue_index !=3D queue_id) + continue; + if (!tstamp->xsk_tx_buffer) + continue; + + igc_ptp_free_tx_buffer(adapter, tstamp); + } + + spin_unlock_irqrestore(&adapter->ptp_tx_lock, flags); +} + static void igc_ptp_disable_tx_timestamp(struct igc_adapter *adapter) { struct igc_hw *hw =3D &adapter->hw; --- base-commit: 05f7e89ab9731565d8a62e3b5d1ec206485eeb0b change-id: 20260212-igc-fix-xdp-tx-tstamp-pagefault-c4abde453862 Best regards, --=20 Zdenek Bouska Siemens, s.r.o. Foundational Technologies