RE: [PATCH net,v3] net: mana: Fix accessing freed irq affinity_hint

[Haiyang Zhang]

> -----Original Message-----
> From: Jakub Kicinski <kuba@xxxxxxxxxx>
> Sent: Monday, February 6, 2023 9:33 PM
> To: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> Cc: linux-hyperv@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; Dexuan Cui
> <decui@xxxxxxxxxxxxx>; KY Srinivasan <kys@xxxxxxxxxxxxx>; Paul Rosswurm
> <paulros@xxxxxxxxxxxxx>; olaf@xxxxxxxxx; vkuznets@xxxxxxxxxx;
> davem@xxxxxxxxxxxxx; wei.liu@xxxxxxxxxx; edumazet@xxxxxxxxxx;
> pabeni@xxxxxxxxxx; leon@xxxxxxxxxx; Long Li <longli@xxxxxxxxxxxxx>;
> ssengar@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> stable@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH net,v3] net: mana: Fix accessing freed irq affinity_hint
> 
> On Mon,  6 Feb 2023 13:28:49 -0800 Haiyang Zhang wrote:
> > After calling irq_set_affinity_and_hint(), the cpumask pointer is
> > saved in desc->affinity_hint, and will be used later when reading
> > /proc/irq/<num>/affinity_hint. So the cpumask variable needs to be
> > persistent. Otherwise, we are accessing freed memory when reading
> > the affinity_hint file.
> >
> > Also, need to clear affinity_hint before free_irq(), otherwise there
> > is a one-time warning and stack trace during module unloading:
> 
> What's the difference from the previous posting? Did you just resend it?

Previously, it failed the auto-check due to some people were not CC-ed.
I resent it with more CCs.

Thanks,
- Haiyang