Re: [PATCH] x86: correct saving and restoring of lapic vectors in suspend/resume

From: Borislav Petkov
Date: Mon Nov 23 2015 - 06:14:03 EST


On Mon, Nov 23, 2015 at 11:59:24AM +0100, Juergen Gross wrote:
> Saving and restoring lapic vectors in lapic_suspend() and
> lapic_resume() is not consistent: the thmr vector saving is guarded
> by a different config option than the restore part. The cmci vector
> isn't handled at all.
>
> Those inconsistencies are not very critical, as the missing cmci
> vector will be set via mce resume handling, the wrong config option
> used for restoring the thmr vector can't be configured differently
> than the one which should be used.
>
> Nevertheless correct the thmr vector restore and add cmci vector
> handling.
>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> ---
> arch/x86/kernel/apic/apic.c | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)

Acked-by: Borislav Petkov <bp@xxxxxxx>

Add Tony to CC and leave in the rest for him to look at:

> diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
> index 2f69e3b..bc06c9d 100644
> --- a/arch/x86/kernel/apic/apic.c
> +++ b/arch/x86/kernel/apic/apic.c
> @@ -2270,6 +2270,7 @@ static struct {
> unsigned int apic_tmict;
> unsigned int apic_tdcr;
> unsigned int apic_thmr;
> + unsigned int apic_cmci;
> } apic_pm_state;
>
> static int lapic_suspend(void)
> @@ -2299,6 +2300,10 @@ static int lapic_suspend(void)
> if (maxlvt >= 5)
> apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
> #endif
> +#ifdef CONFIG_X86_MCE_INTEL
> + if (maxlvt >= 6)
> + apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
> +#endif
>
> local_irq_save(flags);
> disable_local_APIC();
> @@ -2355,10 +2360,14 @@ static void lapic_resume(void)
> apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
> apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
> apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
> -#if defined(CONFIG_X86_MCE_INTEL)
> +#if defined(CONFIG_X86_THERMAL_VECTOR)
> if (maxlvt >= 5)
> apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
> #endif
> +#if defined(CONFIG_X86_MCE_INTEL)
> + if (maxlvt >= 6)
> + apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
> +#endif
> if (maxlvt >= 4)
> apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
> apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
> --
> 2.6.2
>
> --
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--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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