Re: [PATCH net v2] net: usb: lan78xx: fix error handling in lan78xx_open()

[Stefano Munari]

Thanks Andrew. I'll send v3 to net-next without the Fixes tag once it reopens.

Is the Fixes tag being dropped because the bug is unlikely in
practice? For future patches, should similar bugs go to net-next, or
are they not worth fixing?

Stefano


On Tue, Oct 20, 2026 at 11:05 PM Andrew Lunn <andrew@xxxxxxx> wrote:
>
> On Tue, Oct 20, 2026 at 10:26:14PM +0200, Stefano Munari wrote:
> > A failed interrupt URB submission leaves NAPI enabled and EVENT_DEV_OPEN
> > set. A subsequent open enables NAPI again, triggering BUG_ON() in
> > napi_enable().
> >
> > Clear EVENT_DEV_OPEN and disable NAPI on the submission error path.
> >
> > Reproduced using failslab on a Raspberry Pi 3 Model B+ (LAN7515).
> > With the fix, the injected allocation failure returns -ENOMEM and a
> > subsequent open succeeds. Verified connectivity with ping and SSH.
>
> Memory allocations for small blocks generally don't fail, so this is
> theoretical, and very unlikely to happen. Please target net-next, and
> drop the Fixes tag.
>
>     Andrew
>
> ---
> pw-bot: cr