Re: [PATCH 09/17] ACPI, APEI, Add APEI bit support in generic _OSC call

Don Zickus
2011-07-14T14:48:43Z

On Wed, Jul 13, 2011 at 01:14:20PM +0800, Huang Ying wrote:
> In APEI firmware first mode, hardware error is reported by hardware to
> firmware firstly, then firmware reports the error to Linux in a GHES
> error record via POLL/SCI/IRQ/NMI etc.
>
> This may result in some issues if OS has no full APEI support. So
> some firmware implementation will work in a back-compatible mode by
> default. Where firmware will only notify OS in old-fashion, without
> GHES record. For example, for a fatal hardware error, only NMI is
> signaled, no GHES record.
>
> To gain full APEI power on these machines, APEI bit in generic _OSC
> call can be specified to tell firmware that Linux has full APEI
> support. This patch adds the APEI bit support in generic _OSC call.

I have been testing this patch for a couple of weeks with no issues that I
have seen. Without it (and/or the next one), APEI can't really work.

Tested-and-reviewed-by: Don Zickus <dzickus@redhat.com>

>
> Signed-off-by: Huang Ying <ying.huang@intel.com>
> Reviewed-by: Andi Kleen <ak@linux.intel.com>
> Reviewed-by: Matthew Garrett <mjg@redhat.com>
> ---
> drivers/acpi/bus.c | 16 ++++++++++++++--
> include/linux/acpi.h | 2 ++
> 2 files changed, 16 insertions(+), 2 deletions(-)
>
> --- a/drivers/acpi/bus.c
> +++ b/drivers/acpi/bus.c
> @@ -39,6 +39,7 @@
> #include <linux/pci.h>
> #include <acpi/acpi_bus.h>
> #include <acpi/acpi_drivers.h>
> +#include <acpi/apei.h>
> #include <linux/dmi.h>
> #include <linux/suspend.h>
>
> @@ -519,6 +520,7 @@ out_kfree:
> }
> EXPORT_SYMBOL(acpi_run_osc);
>
> +bool osc_sb_apei_support_acked;
> static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
> static void acpi_bus_osc_support(void)
> {
> @@ -541,11 +543,21 @@ static void acpi_bus_osc_support(void)
> #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
> capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_PPC_OST_SUPPORT;
> #endif
> +
> +#ifdef CONFIG_ACPI_APEI_GHES
> + if (!ghes_disable)
> + capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_APEI_SUPPORT;
> +#endif
> if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
> return;
> - if (ACPI_SUCCESS(acpi_run_osc(handle, &context)))
> + if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
> + u32 *capbuf_ret = context.ret.pointer;
> + if (context.ret.length > OSC_SUPPORT_TYPE)
> + osc_sb_apei_support_acked =
> + capbuf_ret[OSC_SUPPORT_TYPE] & OSC_SB_APEI_SUPPORT;
> kfree(context.ret.pointer);
> - /* do we need to check the returned cap? Sounds no */
> + }
> + /* do we need to check other returned cap? Sounds no */
> }
>
> /* --------------------------------------------------------------------------
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -280,6 +280,8 @@ acpi_status acpi_run_osc(acpi_handle han
> #define OSC_SB_CPUHP_OST_SUPPORT 8
> #define OSC_SB_APEI_SUPPORT 16
>
> +extern bool osc_sb_apei_support_acked;
> +
> /* PCI defined _OSC bits */
> /* _OSC DW1 Definition (OS Support Fields) */
> #define OSC_EXT_PCI_CONFIG_SUPPORT 1
> --
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