==> Regarding Re: serious netpoll bug w/NAPI; Matt Mackall <mpm@xxxxxxxxxxx>
adds:
mpm> On Tue, Feb 15, 2005 at 05:49:50PM -0500, Jeff Moyer wrote:
>> ==> Regarding Re: serious netpoll bug w/NAPI; Matt Mackall <mpm@xxxxxxxxxxx>
>> adds:
>>
[snip]
>>
>> Okay, I've only taken a quick glance at this, but I don't quite understand
>> why it's safe to take out the check for the per-cpu queue. Realize that an
>> interrupt may have been serviced on another processor, and a NAPI poll may
>> have been scheduled there.
mpm> Because dev->np->poll_lock now serializes all access to ->poll (when
mpm> netpoll is enabled on said device).
>> Also, could you use the -p flag to diff when you generate your next patch?
>> It makes it *much* easier to review.
mpm> Hmm, somehow my QUILT_DIFF_OPTS got lost, thanks.
mpm> I've just now recovered my SMP+NAPI box, so I can take a stab at
mpm> actually testing this shortly.
I put together a patch against our kernel tree which implements essentially
the same logic as your patch, and it works great: I was able to reproduce
the bug without the patch, and the patched kernel is running just fine.
Let me know when you have another version of your patch, and I will happily
test it in my environment.
Thanks,
Jeff
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