I think we also need cc stable for this. The bug was introduced with commit 4b855ad37194f7bdbb200ce7a1c7051fecb56a08 upstream. ("blk-mq: Create hctx for each present CPU") and that was even backported into 4.12 stable. On 01/12/2018 03:53 AM, Ming Lei wrote: > Hi, > > This two patches support physical CPU hotplug, so that we can make blk-mq > scale well when new physical CPU is added or removed, and this use case > is normal for VM world. > > Also this patchset fixes the following warning reported by Christian > Borntraeger: > > https://marc.info/?l=linux-block&m=151092973417143&w=2 > > Christoph Hellwig (2): > genirq/affinity: assign vectors to all possible CPUs > blk-mq: simplify queue mapping & schedule with each possisble CPU > > block/blk-mq.c | 19 ++++++++----------- > kernel/irq/affinity.c | 30 +++++++++++++++--------------- > 2 files changed, 23 insertions(+), 26 deletions(-) >