Re: [PATCH net-next,v7] net: mana: Add handler for hardware servicing events

[Haiyang Zhang]

> -----Original Message-----
> From: Jakub Kicinski <kuba@xxxxxxxxxx>
> Sent: Thursday, June 12, 2025 9:22 PM
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> Subject: [EXTERNAL] Re: [PATCH net-next,v7] net: mana: Add handler for
> hardware servicing events
> 
> On Tue, 10 Jun 2025 11:42:22 -0700 Haiyang Zhang wrote:
> > v6:
> > Not acquiring module refcnt as suggested by Paolo Abeni.
> 
> TBH I'm not 100% sure this is correct.
> If the service worker operations end up unbinding the driver from
> the device holding the device ref may not prevent the module from
> being unloaded.
> 
> Could you try to trigger that condition? Make that msleep() in the work
> even longer and try to remove the module while the work is sleeping
> there?

Thanks for your suggestion! I tested and found that I can rmmod mana 
during the sleep and caused accessing freed memory. And getting the extra 
module refcnt fixed this (prevented rmmod during sleep). So, I added back
the module refcnt holding, and submitted v8.

Thanks,
- Haiyang