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 2AAEF1DF736; Wed, 6 Nov 2024 12:23:58 +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=1730895839; cv=none; b=D56OcEcrCIBIBIRTbejF/FgSAen6hjrlNKO4geE9PSuNy+9v1SfVHxJwQ+VGqQCeiXG5LYtP4vNhGNS1/Kub41cs6B6De6u8b2Ot/cBx0K7kU20NbXtmqNBbfuCqENxV4GLBAhl/stgoaWv2NGy03x/CITLNGoKKFGu+xmMWKnM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730895839; c=relaxed/simple; bh=9Yc5cuSV+2Nbo7mNRmEy430ECOvNpY2crLO9WmpbnWs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=f6z4xgsnRF0tNfvOU0QBa5vgF2QKXZWUzw0i7ivqIOvKxZal6r0yft2SwMqntcbl1He/EdwXrTJ3p8E3SAopgCcEXO2bQfYeSHql6lS3+Y0lWCHgwl/n+rQ1nr8X1qmnN+GceQebG/J1sM/tRQ/+hcpeDMNfM533Wa/pEG8NZdU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=t7uknraj; 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="t7uknraj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E3AAC4CECD; Wed, 6 Nov 2024 12:23:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1730895838; bh=9Yc5cuSV+2Nbo7mNRmEy430ECOvNpY2crLO9WmpbnWs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t7uknrajm7S9UMrsgUEs/vYQz0Uo499gvo/gebZrcZQIHV2b4m4hRjNTlQvB8VcSO IA2HQvlb6RMynaq8QWaYxM8C4iTbtzoSWmS3u27xchDPzvBsQhB9U6DvBEnPZL/m5C zMsiD9w13m7lrT/EoJHD/Z5oSUiGpIRs13vbeTU8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wander Lairson Costa , Yuying Ma , Przemek Kitszel , Rafal Romanowski , Jacob Keller , Simon Horman , Paolo Abeni , Sasha Levin Subject: [PATCH 4.19 328/350] igb: Disable threaded IRQ for igb_msix_other Date: Wed, 6 Nov 2024 13:04:16 +0100 Message-ID: <20241106120328.830089279@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241106120320.865793091@linuxfoundation.org> References: <20241106120320.865793091@linuxfoundation.org> User-Agent: quilt/0.67 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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wander Lairson Costa [ Upstream commit 338c4d3902feb5be49bfda530a72c7ab860e2c9f ] During testing of SR-IOV, Red Hat QE encountered an issue where the ip link up command intermittently fails for the igbvf interfaces when using the PREEMPT_RT variant. Investigation revealed that e1000_write_posted_mbx returns an error due to the lack of an ACK from e1000_poll_for_ack. The underlying issue arises from the fact that IRQs are threaded by default under PREEMPT_RT. While the exact hardware details are not available, it appears that the IRQ handled by igb_msix_other must be processed before e1000_poll_for_ack times out. However, e1000_write_posted_mbx is called with preemption disabled, leading to a scenario where the IRQ is serviced only after the failure of e1000_write_posted_mbx. To resolve this, we set IRQF_NO_THREAD for the affected interrupt, ensuring that the kernel handles it immediately, thereby preventing the aforementioned error. Reproducer: #!/bin/bash # echo 2 > /sys/class/net/ens14f0/device/sriov_numvfs ipaddr_vlan=3 nic_test=ens14f0 vf=${nic_test}v0 while true; do ip link set ${nic_test} mtu 1500 ip link set ${vf} mtu 1500 ip link set $vf up ip link set ${nic_test} vf 0 vlan ${ipaddr_vlan} ip addr add 172.30.${ipaddr_vlan}.1/24 dev ${vf} ip addr add 2021:db8:${ipaddr_vlan}::1/64 dev ${vf} if ! ip link show $vf | grep 'state UP'; then echo 'Error found' break fi ip link set $vf down done Signed-off-by: Wander Lairson Costa Fixes: 9d5c824399de ("igb: PCI-Express 82575 Gigabit Ethernet driver") Reported-by: Yuying Ma Reviewed-by: Przemek Kitszel Tested-by: Rafal Romanowski Signed-off-by: Jacob Keller Reviewed-by: Simon Horman Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/igb/igb_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 3a65dccc08ba8..5867e2db17fd5 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -943,7 +943,7 @@ static int igb_request_msix(struct igb_adapter *adapter) int i, err = 0, vector = 0, free_vector = 0; err = request_irq(adapter->msix_entries[vector].vector, - igb_msix_other, 0, netdev->name, adapter); + igb_msix_other, IRQF_NO_THREAD, netdev->name, adapter); if (err) goto err_out; -- 2.43.0