Subject: Re: [Bulk] Re: [PATCH 1/2] [PCI] Check that MWI bit really did get set

From: Matthew Wilcox <[email-masked]>
Date: Sun, 15 Oct 2006 07:57:56 -0600

On Sun, Oct 15, 2006 at 03:21:22PM +0100, Alan Cox wrote:
> Ar Sul, 2006-10-15 am 00:08 -0700, ysgrifennodd David Brownell:
> > Since it's not an error, there should be no such printk ... which
> > is exactly how it's coded above.
> 
> The underlying bug is that someone marked pci_set_mwi must-check, that's
> wrong for most of the drivers that use it. If you remove the must check
> annotation from it then the problem and a thousand other spurious
> warnings go away.

There's only about 20 users of pci_set_mwi ... about 12 of them seem to
check it, one of them uses a variable called
compiler_warning_pointless_fix which leaves about 7 warnings to be
removed by removing the __must_check.

However, I do believe the __must_check should be removed.  For example,
the LSI 53c1030 has *nothing* to be done if setting MWI fails.  It just
doesn't work, and the device copes.  It's not like Tulip or sym53c8xx
where there are additional bits to be set or cleared in control registers.