Re: [6.12.y] WARNING: CPU: 0 PID: 681 at block/blk-mq-cpumap.c:90 blk_mq_map_hw_queues+0xcf/0xe0

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Sat, May 03, 2025 at 10:05:29AM +0800, Wang Yugui wrote:
> Hi,
> Cc: Greg Kroah-Hartman
> 
> > Hi,
> > 
> > I noticed a WARNING in recent 6.12.y kernel.
> > 
> > This WARNING happen on 6.12.26/6.12.25, but not happen on 6.12.20.
> > 
> > More bisect job need to be done, but reporti it firstly.
> > 
> > [   13.288365] ------------[ cut here ]------------
> > [   13.288366] WARNING: CPU: 0 PID: 681 at block/blk-mq-cpumap.c:90 blk_mq_map_hw_queues+0xcf/0xe0
> > void blk_mq_map_hw_queues(struct blk_mq_queue_map *qmap,
> >               struct device *dev, unsigned int offset)
> > {
> > ...
> > ...
> > fallback:
> > L90：    WARN_ON_ONCE(qmap->nr_queues > 1);
> >     blk_mq_clear_mq_map(qmap);
> > }
> > 
> 
> The following patch fixed this WARNING.
> 
> From a9ae6fe1c319c4776c2b11e85e15109cd3f04076 Mon Sep 17 00:00:00 2001
> From: Daniel Wagner <wagi@kernel.org>
> Date: Thu, 23 Jan 2025 14:08:29 +0100
> Subject: [PATCH] blk-mq: create correct map for fallback case
> 
> please pull it to 6.12.y.

But the commit that this one says it fixes is NOT in the 6.12.y tree.
So why would this commit fix the issue?

And why haven't you cc:ed the authors involved in these changes?

confused,

greg k-h