Hi James,
Thanks for your comments.
On 2017/3/6 18:00, James Morse wrote:
> Hi Xie XiuQi,
>
> On 03/03/17 10:39, Xie XiuQi wrote:
>> ARM APEI extension proposal added SEI (asynchronous SError interrupt)
>> notification type for ARMv8.
>>
>> Add a new GHES error source handling function for SEI. In firmware
>> first mode, if an error source's notification type is SEI. Then GHES
>> could parse and report the detail error information.
>
> This patch doesn't apply to any upstream tree. Is this based on Tyler's larger
> UEFI/ACPI update series? If so, please mention this in your cover letter,
> (Nit:
> please include a cover letter when sending two or more patches!).
>
Yes, this patch is based on Tyler's series "[PATCH V11 00/10] Add UEFI 2.6 and
ACPI 6.1 updates
for RAS on ARM64" and linux-next 20170302.
I'll add a cover letter next time, thanks.
> What happens if the SError Interrupt arrives while KVM was doing its work? We
> set the HCR_EL2.AMO bit when running a guest, so KVM may receive these instead
> of the host kernel.
>
OK, I'll do it in next version.
>
>> diff --git a/drivers/acpi/apei/Kconfig b/drivers/acpi/apei/Kconfig
>> index 1122d7f..a32f046 100644
>> --- a/drivers/acpi/apei/Kconfig
>> +++ b/drivers/acpi/apei/Kconfig
>> @@ -18,6 +18,20 @@ config HAVE_ACPI_APEI_SEA
>> option allows the OS to look for such hardware error record, and
>> take appropriate action.
>>
>> +config ACPI_APEI_SEI
>> + bool "APEI Asynchronous SError Interrupt logging/recovering support"
>> + depends on ARM64 && ACPI_APEI_GHES
>> + help
>> + This option should be enabled if the system supports
>> + firmware first handling of SEI (asynchronous SError interrupt).
>> +
>> + SEI happens with invalid instruction access or asynchronous exceptions
>> + on ARMv8 systems. If a system supports firmware first handling of SEI,
>> + the platform analyzes and handles hardware error notifications from
>> + SEI, and it may then form a HW error record for the OS to parse and
>> + handle. This option allows the OS to look for such hardware error
>> + record, and take appropriate action.
>> +
>> config ACPI_APEI
>> bool "ACPI Platform Error Interface (APEI)"
>> select MISC_FILESYSTEMS
>> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
>> index 3e4ea1b..d084a09 100644
>> --- a/drivers/acpi/apei/ghes.c
>> +++ b/drivers/acpi/apei/ghes.c
>> @@ -850,6 +850,50 @@ static inline void ghes_sea_remove(struct ghes *ghes)
>> }
>> #endif /* CONFIG_HAVE_ACPI_APEI_SEA */
>>
>> +#ifdef CONFIG_ACPI_APEI_SEI
>> +static LIST_HEAD(ghes_sei);
>> +
>> +void ghes_notify_sei(void)
>> +{
>> + struct ghes *ghes;
>> +
>> + /*
>> + * synchronize_rcu() will wait for nmi_exit(), so no need to
>
> Where nmi_exit()?
>
> This nmi enter/exit was to prevent APEI being interrupted by APEI and trying
> to
> take the same set of locks. APEI masks IRQs to prevent this happening
> normally,
> but Synchronous External Abort couldn't be masked.
> We don't mask Asynchronous Exceptions in APEI so the same thing can happen
> here.
> Adding nmi_{enter,exit}() round the ghes call in the arch bad_mode() will
> prevent this lockup.
>
Thank you for your detailed explanation, I'll add it in next version.
Thanks,
Xie XiuQi
