[PATCH V7 1/3] powerpc/pci: Make sure ISA IO base is not zero

[Jia Hongtao-B38951]

> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Thursday, August 16, 2012 1:29 AM
> To: Jia Hongtao-B38951
> Cc: linuxppc-dev at lists.ozlabs.org; galak at kernel.crashing.org;
> benh at kernel.crashing.org; Li Yang-R58472; Wood Scott-B07421
> Subject: Re: [PATCH V7 1/3] powerpc/pci: Make sure ISA IO base is not
> zero
> 
> On 08/15/2012 03:57 AM, Jia Hongtao wrote:
> > From: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> >
> > Some platforms like QEMU treat 0 as an invalid address for ISA IO base.
> > So we make sure that ISA IO base will never be zero. By functionality
> > this is equivalent to assgin the first pci bus detected as a primary
> bus.
> >
> > Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> > Signed-off-by: Jia Hongtao <B38951 at freescale.com>
> 
> When did Ben post this?
> 
> Suggesting a temporary workaround in an e-mail is *not* the same as
> posting a patch, and definitely not the same as providing a signed-off-by
> which AFAICT you forged.  Don't do that.
> 
> > ---
> >  arch/powerpc/kernel/pci-common.c |    2 +-
> >  1 files changed, 1 insertions(+), 1 deletions(-)
> >
> > diff --git a/arch/powerpc/kernel/pci-common.c
> > b/arch/powerpc/kernel/pci-common.c
> > index 0f75bd5..2a09aa5 100644
> > --- a/arch/powerpc/kernel/pci-common.c
> > +++ b/arch/powerpc/kernel/pci-common.c
> > @@ -734,7 +734,7 @@ void __devinit pci_process_bridge_OF_ranges(struct
> pci_controller *hose,
> >  			hose->io_base_virt = ioremap(cpu_addr, size);
> >
> >  			/* Expect trouble if pci_addr is not 0 */
> > -			if (primary)
> > +			if (primary || !isa_io_base)
> >  				isa_io_base =
> >  					(unsigned long)hose->io_base_virt;  #endif
> /* CONFIG_PPC32 */
> >
> 
> Didn't I already point out that this has problems when the primary bus is
> not the first to be probed?  If your answer is that you fix that in a
> later patch, that breaks bisectability.
> 
> -Scott

Sorry, my answer is not that I fix that in later patch.
My answer is, without this patch there is also problem with non-first-primary.
That is to say the bisectability problem has been already there.
The problem is not brought by this patch.

- Hongtao.