Re: [PATCH v2 1/2] mce: acpi/apei: Honour Firmware First for MCA banks listed in APEI HEST CMC

[Borislav Petkov <bp@alien8.de>]

On Tue, Jun 25, 2013 at 11:16:32PM +0530, Naveen N. Rao wrote:
> Tony, Boris,
> Can you please see if the comments in the below patch include the details you
> were expecting?
> 
> Thanks,
> Naveen
> 
> --
> Add comments to clarify usage of the various bitfields in the MCA subsystem
> 
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> ---
>  arch/x86/kernel/cpu/mcheck/mce.c       |    5 ++++-
>  arch/x86/kernel/cpu/mcheck/mce_intel.c |    9 +++++++++
>  2 files changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
> index 9239504..bf49cdb 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce.c
> @@ -89,7 +89,10 @@ static DECLARE_WAIT_QUEUE_HEAD(mce_chrdev_wait);
>  static DEFINE_PER_CPU(struct mce, mces_seen);
>  static int			cpu_missing;
>  
> -/* MCA banks polled by the period polling timer for corrected events */
> +/*
> + * MCA banks polled by the period polling timer for corrected events.
> + * With Intel CMCI, this only has MCA banks which do not support CMCI (if any).
> + */
>  DEFINE_PER_CPU(mce_banks_t, mce_poll_banks) = {
>  	[0 ... BITS_TO_LONGS(MAX_NR_BANKS)-1] = ~0UL
>  };
> diff --git a/arch/x86/kernel/cpu/mcheck/mce_intel.c b/arch/x86/kernel/cpu/mcheck/mce_intel.c
> index ae1697c..2816f53 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce_intel.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce_intel.c
> @@ -24,6 +24,15 @@
>   * Also supports reliable discovery of shared banks.
>   */
>  
> +/*
> + * Indicates MCA banks controlled by the current cpu for CMCI. Note that this
> + * can change when a cpu is offlined or brought online since some MCA banks
> + * are shared across cpus. When a cpu is offlined, cmci_clear() disables CMCI
> + * on all banks owned by the cpu and clears this bitfield. At this point,
> + * cmci_rediscover() kicks in and a different cpu may end up taking
> + * ownership of some of the shared MCA banks that were previously owned
> + * by the offlined cpu.
> + */
>  static DEFINE_PER_CPU(mce_banks_t, mce_banks_owned);

Yep, it looks ok to me.

Acked-by: Borislav Petkov <bp@suse.de>

Thanks.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
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