Re: [PATCH] Fix VMI crash on boot in 2.6.27, 2.6.28 kernels

[Greg KH <gregkh@suse.de>]

On Thu, Dec 11, 2008 at 02:23:11PM -0800, Zachary Amsden wrote:
> On Wed, 2008-12-10 at 19:31 -0800, Greg KH wrote:
> 
> > > +#ifdef CONFIG_VMI
> > > +	/* VMI may relocate the fixmap; do this before touching ioremap area */
> > > +	vmi_init();
> > > +#endif
> > 
> > Shouldn't the #ifdef not be needed here if the .h files are set up
> > properly for the vmi_init prototype?  Please try to keep them out of .c
> > files wherever possible.
> 
> Yes, they should.  Judging by setup.c though, you would think the
> opposite... in any case I fixed it.  Please apply - and yes, I tested
> compile both ways.

> VMI initialiation can relocate the fixmap, causing early_ioremap
> to malfunction if it is initialized before the relocation.
> To fix this, VMI activation is split into two phases; the detection,
> which must happen before setting up ioremap, and the activation,
> which must happen after parsing early boot parameters.
> 
> This fixes a crash on boot when VMI is enabled under VMware.
> 
> Signed-off-by: Zachary Amsden <zach@vmware.com>
> 
> diff --git a/arch/x86/include/asm/vmi.h b/arch/x86/include/asm/vmi.h
> index b7c0dea..128958a 100644
> --- a/arch/x86/include/asm/vmi.h
> +++ b/arch/x86/include/asm/vmi.h
> @@ -223,9 +223,15 @@ struct pci_header {
>  } __attribute__((packed));
>  
>  /* Function prototypes for bootstrapping */
> +#ifdef CONFIG_VMI
>  extern void vmi_init(void);
> +extern void vmi_activate(void);
>  extern void vmi_bringup(void);
> -extern void vmi_apply_boot_page_allocations(void);
> +#else
> +#define vmi_init()
> +#define vmi_activate()
> +#define vmi_bringup()
> +#endif

static inline please, don't use #defines for function prototypes, it's
not nice.  See Andrew's previous rants about this for details :)

thanks,

greg k-h