On Wed, Aug 22, 2012 at 06:00:54PM +0530, Naveen N. Rao wrote:
> The ACPI spec doesn't provide for a way for the bios to pass down
> recommended thresholds to the OS on a _per-bank_ basis. This patch adds
> a new boot option, which if passed, allows bios to initialize the CMCI
> threshold. In such a case, we simply skip programming any threshold
> value.
>
> As fail-safe, we initialize threshold to 1 if some banks have not been
> initialized by the bios and warn the user.
>
> Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
> ---
> Documentation/x86/x86_64/boot-options.txt | 5 ++++
> arch/x86/include/asm/mce.h | 1 +
> arch/x86/kernel/cpu/mcheck/mce.c | 4 +++
> arch/x86/kernel/cpu/mcheck/mce_intel.c | 39
> +++++++++++++++++++++++++++--
> 4 files changed, 46 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/x86/x86_64/boot-options.txt
> b/Documentation/x86/x86_64/boot-options.txt
> index c54b4f5..ec92540 100644
> --- a/Documentation/x86/x86_64/boot-options.txt
> +++ b/Documentation/x86/x86_64/boot-options.txt
> @@ -50,6 +50,11 @@ Machine check
> monarchtimeout:
> Sets the time in us to wait for other CPUs on machine checks. 0
> to disable.
> + mce=bios_cmci_threshold
> + Don't overwrite the bios-set CMCI threshold. This boot option
> + prevents Linux from overwriting the CMCI threshold set by the
> + bios. Without this option, Linux always sets the CMCI
> + threshold to 1.
>
> nomce (for compatibility with i386): same as mce=off
>
> diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
> index a3ac52b..8ad5078 100644
> --- a/arch/x86/include/asm/mce.h
> +++ b/arch/x86/include/asm/mce.h
> @@ -171,6 +171,7 @@ DECLARE_PER_CPU(struct device *, mce_device);
> #ifdef CONFIG_X86_MCE_INTEL
> extern int mce_cmci_disabled;
> extern int mce_ignore_ce;
> +extern int mce_bios_cmci_threshold;
> void mce_intel_feature_init(struct cpuinfo_x86 *c);
> void cmci_clear(void);
> void cmci_reenable(void);
> diff --git a/arch/x86/kernel/cpu/mcheck/mce.c
> b/arch/x86/kernel/cpu/mcheck/mce.c
> index 292d025..401359d 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce.c
> @@ -82,6 +82,7 @@ static int mce_panic_timeout
> __read_mostly;
> static int mce_dont_log_ce __read_mostly;
> int mce_cmci_disabled __read_mostly;
> int mce_ignore_ce __read_mostly;
> +int mce_bios_cmci_threshold __read_mostly;
> int mce_ser __read_mostly;
AFAICT, this is actually a single-bit flag but we're using a whole
integer for it and from looking at the other boot options a couple of
them are used as flags too.
Care to define a
struct boot_flags {
__u64 mce_bios_cmci_threshold : 1,
__reserved : 63;
};
and use
boot_flags.mce_bios_cmci_threshold
in the conditionals below instead?
I'll try to convert the rest of them to that struct and thus save some
more space...
Thanks.
--
Regards/Gruss,
Boris.
Advanced Micro Devices GmbH
Einsteinring 24, 85609 Dornach
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