Re: [RFC PATCH v4 3/7] PCI: Ignore resource_alignment if PCI_PROBE_ONLY was set

[Yongji Xie]

On 2016/3/17 0:31, Alex Williamson wrote:
> On Mon,  7 Mar 2016 15:48:34 +0800
> Yongji Xie <xyjxie@xxxxxxxxxxxxxxxxxx> wrote:
>
> > The resource_alignment will releases memory resources
> > allocated by firmware so that kernel can reassign new
> > resources later on. But this will cause the problem
> > that no resources can be allocated by kernel if
> > PCI_PROBE_ONLY was set, e.g. on pSeries platform
> > because PCI_PROBE_ONLY force kernel to use firmware
> > setup and not to reassign any resources.
> >
> > To solve this problem, this patch ignores
> > resource_alignment if PCI_PROBE_ONLY was set.
> >
> > Signed-off-by: Yongji Xie <xyjxie@xxxxxxxxxxxxxxxxxx>
> > ---
> >   Documentation/kernel-parameters.txt |    2 ++
> >   drivers/pci/probe.c                 |    3 ++-
> >   2 files changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
> > index d8b29ab..8028631 100644
> > --- a/Documentation/kernel-parameters.txt
> > +++ b/Documentation/kernel-parameters.txt
> > @@ -2922,6 +2922,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
> >   				windows need to be expanded.
> >   				noresize: Don't change the resources' sizes when
> >   				reassigning alignment.
> > +				Note that this option will not work if
> > +				PCI_PROBE_ONLY is set.
> How would a user have any idea if this is set?

I found the PCI_PROBE_ONLY is set on pSeries, maple and
arm with "firmware" kernel parameter enabled.

So can we say: Note that this option will not work on pSeries,
maple and arm with "firmware" kernel parameter enabled?
Or do you have any suggestion?

Thanks,
Yongji Xie