On Thu, Aug 17, 2017 at 12:24:47PM +0200, Christoph Hellwig wrote:
> While pci_irq_get_affinity should never fail for SMP kernel that
> implement the affinity mapping, it will always return NULL in the
> UP case, so provide a fallback mapping of all queues to CPU 0 in
> that case.
Reviewed-by: Omar Sandoval <osandov@xxxxxx>
Has nvme been fixed to not crash if blk_mq_alloc_tag_set() fails?
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> block/blk-mq-pci.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/block/blk-mq-pci.c b/block/blk-mq-pci.c
> index 0c3354cf3552..76944e3271bf 100644
> --- a/block/blk-mq-pci.c
> +++ b/block/blk-mq-pci.c
> @@ -36,12 +36,18 @@ int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev)
> for (queue = 0; queue < set->nr_hw_queues; queue++) {
> mask = pci_irq_get_affinity(pdev, queue);
> if (!mask)
> - return -EINVAL;
> + goto fallback;
>
> for_each_cpu(cpu, mask)
> set->mq_map[cpu] = queue;
> }
>
> return 0;
> +
> +fallback:
> + WARN_ON_ONCE(set->nr_hw_queues > 1);
> + for_each_possible_cpu(cpu)
> + set->mq_map[cpu] = 0;
> + return 0;
> }
> EXPORT_SYMBOL_GPL(blk_mq_pci_map_queues);
> --
> 2.11.0
>