Re: [patch 3/5] x2apic, IR: cleanup panic() with nox2apic bootoption

From: Ingo Molnar
Date: Tue Apr 21 2009 - 03:01:33 EST



* Suresh Siddha <suresh.b.siddha@xxxxxxxxx> wrote:

> Instead of panic() ignore the "nox2apic" boot option when BIOS has
> already enabled x2apic prior to OS handover.
>
> Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
> Cc: Weidong Han <weidong.han@xxxxxxxxx>
> ---
>
> Index: tip/arch/x86/kernel/apic/apic.c
> ===================================================================
> --- tip.orig/arch/x86/kernel/apic/apic.c
> +++ tip/arch/x86/kernel/apic/apic.c
> @@ -142,8 +142,12 @@ static int x2apic_preenabled;
> static int disable_x2apic;
> static __init int setup_nox2apic(char *str)
> {
> - if (x2apic_enabled())
> - panic("Bios already enabled x2apic, can't enforce nox2apic");
> + if (x2apic_enabled()) {
> + pr_warning("Bios already enabled x2apic, "
> + "can't enforce nox2apic");

Btw., in such cases we dont break printk strings in the middle but
ignore the checkpatch warning. I fixed it up in your patch.

The advantage is that if someone, based on a dmesg line, types:

git grep Bios already enabled x2apic, can't enforce nox2apic

the right source code line will be found. In the broken-up-line case
this wont work. (grep is fundamentally single-line)

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/