Re: WARNING: at arch/x86/kernel/apic/apic.c:249 native_apic_write_dummy

[Cyrill Gorcunov <gorcunov@gmail.com>]

[Vegard Nossum - Wed, Jun 17, 2009 at 06:33:31PM +0200]
| 2009/6/17 Cyrill Gorcunov <gorcunov@gmail.com>:
| > Vegard, could you test the patch?
| >
| >        -- Cyrill
| > ---
| >
| > If we have apic disabled we don't even switch to APIC mode and do not
| > calling for connect_bsp_APIC. Though on SMP compiled kernel the
| > native_machine_shutdown does try to write the apic register anyway.
| > Fix it with explicit check if we really should touch apic registers.
| >
| > Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
| > Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
| > ---
| >  arch/x86/kernel/apic/io_apic.c |    4 +++-
| >  1 file changed, 3 insertions(+), 1 deletion(-)
| >
| > Index: linux-2.6.git/arch/x86/kernel/apic/io_apic.c
| > =====================================================================
| > --- linux-2.6.git.orig/arch/x86/kernel/apic/io_apic.c
| > +++ linux-2.6.git/arch/x86/kernel/apic/io_apic.c
| > @@ -2003,7 +2003,9 @@ void disable_IO_APIC(void)
| >        /*
| >         * Use virtual wire A mode when interrupt remapping is enabled.
| >         */
| > -       disconnect_bsp_APIC(!intr_remapping_enabled && ioapic_i8259.pin != -1);
| > +       if (cpu_has_apic)
| > +               disconnect_bsp_APIC(!intr_remapping_enabled &&
| > +                               ioapic_i8259.pin != -1);
| >  }
| >
| >  #ifdef CONFIG_X86_32
| >
| 
| Seems to work here:
| 
| [  317.596743] ACPI: Preparing to enter system sleep state S5
| [  317.633421] Disabling non-boot CPUs ...
| [  317.637493] Power down.
| [  317.638305] acpi_power_off called
| 
| and no warning.
| 
| Thanks!
| 
| 
| Vegard
|

Thanks for testing Vegard! I'll recheck again and send
properly formed patch a bit later.
 
	-- Cyrill