This is a note to let you know that I've just added the patch titled nvme/pci: Fix read queue count to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nvme-pci-fix-read-queue-count.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e49eb792d36f55c7def0b2106c527eba884eea6a Author: Keith Busch <kbusch@xxxxxxxxxx> Date: Fri Dec 6 08:11:17 2019 +0900 nvme/pci: Fix read queue count [ Upstream commit 7e4c6b9a5d22485acf009b3c3510a370f096dd54 ] If nvme.write_queues equals the number of CPUs, the driver had decreased the number of interrupts available such that there could only be one read queue even if the controller could support more. Remove the interrupt count reduction in this case. The driver wouldn't request more IRQs than it wants queues anyway. Reviewed-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 29d7427c2b19..14d513087a14 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2060,7 +2060,6 @@ static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues) .priv = dev, }; unsigned int irq_queues, this_p_queues; - unsigned int nr_cpus = num_possible_cpus(); /* * Poll queues don't need interrupts, but we need at least one IO @@ -2071,10 +2070,7 @@ static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues) this_p_queues = nr_io_queues - 1; irq_queues = 1; } else { - if (nr_cpus < nr_io_queues - this_p_queues) - irq_queues = nr_cpus + 1; - else - irq_queues = nr_io_queues - this_p_queues + 1; + irq_queues = nr_io_queues - this_p_queues + 1; } dev->io_queues[HCTX_TYPE_POLL] = this_p_queues;