Re: [PATCH for review] [89/145] x86_64: Allow early_param and identical __setup to exist

Len Brown
2006-08-16T16:24:22Z

On Thursday 10 August 2006 15:36, Andi Kleen wrote:
>
> From: Rusty Russell <rusty@rustcorp.com.au>
> We currently assume that boot parameters which are handled by
> early_param() will not overlap boot parameters handled by __setup: if
> they do, behaviour is dependent on link order, usually meaning __setup
> will not get called.
>
> ACPI wants to use early_param("pci"), and pci uses __setup("pci="), so
> we modify the core to let them coexist: "pci=noacpi" will now get
> passed to both.

For what it is worth....
"pci=noacpi" is the same as "acpi=noirq", except in addition it also sets acpi_pci_disabled.

For some time, it seems that "acpi=noirq" has been sufficient where "pci=noacpi" was being used.
Thopugh we used to have some BIOS quirks that would fool ACPI root bus initialization,
I think that we are probably past those.

So I'll venture that today any uses of "pci=noacpi" could likely be down-graded
to "acpi=noirq", and "pci=noacpi" could be deleted --- though it seems that people
tend to get very upset when cmdline options are removed...

thanks,
-Len

> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
> Signed-off-by: Andi Kleen <ak@suse.de>
>
> ---
> init/main.c | 12 ++++++++----
> 1 files changed, 8 insertions(+), 4 deletions(-)
>
> Index: linux/init/main.c
> ===================================================================
> --- linux.orig/init/main.c
> +++ linux/init/main.c
> @@ -162,16 +162,19 @@ extern struct obs_kernel_param __setup_s
> static int __init obsolete_checksetup(char *line)
> {
> struct obs_kernel_param *p;
> + int had_early_param = 0;
>
> p = __setup_start;
> do {
> int n = strlen(p->str);
> if (!strncmp(line, p->str, n)) {
> if (p->early) {
> - /* Already done in parse_early_param? (Needs
> - * exact match on param part) */
> + /* Already done in parse_early_param?
> + * (Needs exact match on param part).
> + * Keep iterating, as we can have early
> + * params and __setups of same names 8( */
> if (line[n] == '\0' || line[n] == '=')
> - return 1;
> + had_early_param = 1;
> } else if (!p->setup_func) {
> printk(KERN_WARNING "Parameter %s is obsolete,"
> " ignored\n", p->str);
> @@ -181,7 +184,8 @@ static int __init obsolete_checksetup(ch
> }
> p++;
> } while (p < __setup_end);
> - return 0;
> +
> + return had_early_param;
> }
>
> /*
> -
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