Re: SATA resume slowness, e1000 MSI warning

[Michael S. Tsirkin]

> Quoting Eric W. Biederman <ebiederm@xxxxxxxxxxxx>:
> Subject: Re: SATA resume slowness, e1000 MSI warning
> 
> "Michael S. Tsirkin" <mst@xxxxxxxxxxxxxx> writes:
> 
> >> Rumor has it that some pci devices can't tolerate < 32bit accesses.
> >> Although I have never met one.
> >
> > hopefully not bridge devices?
> >
> >> The two factors together suggest that
> >> for generic code it probably makes sense to operate on 32bit
> >> quantities, and just to ignore the read-only portion.
> >
> > The code for regular devices seems to use 16-bit accesses, so
> > I think it's best to stay consistent. Or do you want to change this too?
> 
> If we are stomping rare probabilities we might as well change that too.
> The code to save pci-x state is relatively recent.  So it probably just
> hasn't met a problem device yet (assuming they exist).

OK I guess. I gather we assume writing read-only registers has no side effects?
Are there rumors circulating wrt to these?

-- 
MST
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