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 B74B61DED58; Wed, 6 Nov 2024 12:25:27 +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=1730895927; cv=none; b=ek75j3N4TUl8dmj0oyClEAfMAqEA38dGkU6tRv4NDagXvyHFX/5+tlfPlU6KVIPh8YUj3CAjJRwtZFgC7svuKFrl0FVOxbASb+sxuowpI1mbT+Ltf7/wIrscb84F7XV5TKyKmIomekfXJaV4N6CWjKIhyA+ShdSULDOTTvdYK9g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730895927; c=relaxed/simple; bh=7oznihawD9c5e+4wOcQPLTJVy10phO5BJ7Lo/9USejU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZmYUSbWUSnhJwBihqqXOBe6JFS0wVVoR35VzJT/Xjp9iyof0sNQKNd9eGoTIEZBWgDU3e1HmMIeRwwQpO7zDfllk+lWXZf4UOiVjlIuQ/iIyg/MAbNXjb+x8vfv/0HIVn3hM8ZBHCL9iBsWGjXzXpuksQ2xmAmzr/f+MR0P3QUk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=gj/Hie5L; 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="gj/Hie5L" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7517C4CECD; Wed, 6 Nov 2024 12:25:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1730895927; bh=7oznihawD9c5e+4wOcQPLTJVy10phO5BJ7Lo/9USejU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gj/Hie5Lf70lqFlm8So4BEjNBnk+kwa7dvLO7NVor8omWNHXy19ME4iqWRDjWRbl9 N2nFioVzDSg3CqU/p29ktlEMNQgDNojOP3YIwKCxMiV1g3SY9T/xCV6h8PZL+9A+Kl 7DgHL7oI386xoQ2W8qMJRsc0VojU8xG9TPOzU9Ho= 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 6.11 030/245] igb: Disable threaded IRQ for igb_msix_other Date: Wed, 6 Nov 2024 13:01:23 +0100 Message-ID: <20241106120319.970840571@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241106120319.234238499@linuxfoundation.org> References: <20241106120319.234238499@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 6.11-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 f1d0881687233..b83df5f94b1f5 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -907,7 +907,7 @@ 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