linux-kernel - [PATCH 3/4] nvme: pci: pass IRQF_RESCURE_THREAD to request_threaded

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 27 Aug 2019 16:53:43 +0800
From:   Ming Lei <ming.lei@...hat.com>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     linux-kernel@...r.kernel.org, Ming Lei <ming.lei@...hat.com>,
        Long Li <longli@...rosoft.com>, Ingo Molnar <mingo@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Keith Busch <keith.busch@...el.com>, Jens Axboe <axboe@...com>,
        Christoph Hellwig <hch@....de>,
        Sagi Grimberg <sagi@...mberg.me>,
        John Garry <john.garry@...wei.com>,
        Hannes Reinecke <hare@...e.com>,
        linux-nvme@...ts.infradead.org, linux-scsi@...r.kernel.org
Subject: [PATCH 3/4] nvme: pci: pass IRQF_RESCURE_THREAD to request_threaded_irq

If one vector is spread on several CPUs, usually the interrupt is only
handled on one of these CPUs. Meantime, IO can be issued to the single
hw queue from different CPUs concurrently, this way is easy to cause
IRQ flood and CPU lockup.

Pass IRQF_RESCURE_THREAD in above case for asking genirq to handle
interrupt in the rescurd thread when irq flood is detected.

Cc: Long Li <longli@...rosoft.com>
Cc: Ingo Molnar <mingo@...hat.com>,
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Keith Busch <keith.busch@...el.com>
Cc: Jens Axboe <axboe@...com>
Cc: Christoph Hellwig <hch@....de>
Cc: Sagi Grimberg <sagi@...mberg.me>
Cc: John Garry <john.garry@...wei.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Hannes Reinecke <hare@...e.com>
Cc: linux-nvme@...ts.infradead.org
Cc: linux-scsi@...r.kernel.org
Signed-off-by: Ming Lei <ming.lei@...hat.com>
---
 drivers/nvme/host/pci.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 45a80b708ef4..0b8d49470230 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1501,8 +1501,21 @@ static int queue_request_irq(struct nvme_queue *nvmeq)
 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
 				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
 	} else {
-		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
-				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
+		char *devname;
+		const struct cpumask *mask;
+		unsigned long irqflags = IRQF_SHARED;
+		int vector = pci_irq_vector(pdev, nvmeq->cq_vector);
+
+		devname = kasprintf(GFP_KERNEL, "nvme%dq%d", nr, nvmeq->qid);
+		if (!devname)
+			return -ENOMEM;
+
+		mask = pci_irq_get_affinity(pdev, nvmeq->cq_vector);
+		if (mask && cpumask_weight(mask) > 1)
+			irqflags |= IRQF_RESCUE_THREAD;
+
+		return request_threaded_irq(vector, nvme_irq, NULL, irqflags,
+				devname, nvmeq);
 	}
 }
 
-- 
2.20.1