[PATCH V15 06/11] acpi: apei: handle SEA notification type for ARMv8

Baicar, Tyler
2017-04-25T17:41:39Z

On 4/25/2017 11:21 AM, Borislav Petkov wrote:
> On Tue, Apr 18, 2017 at 05:05:18PM -0600, Tyler Baicar wrote:
>> ARM APEI extension proposal added SEA (Synchronous External Abort)
>> notification type for ARMv8.
>> Add a new GHES error source handling function for SEA. If an error
>> source's notification type is SEA, then this function can be registered
>> into the SEA exception handler. That way GHES will parse and report
>> SEA exceptions when they occur.
>> An SEA can interrupt code that had interrupts masked and is treated as
>> an NMI. To aid this the page of address space for mapping APEI buffers
>> while in_nmi() is always reserved, and ghes_ioremap_pfn_nmi() is
>> changed to use the helper methods to find the prot_t to map with in
>> the same way as ghes_ioremap_pfn_irq().
> ...
>
>> @@ -518,6 +520,17 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
>> pr_err("Synchronous External Abort: %s (0x%08x) at 0x%016lx\n",
>> inf->name, esr, addr);
>>
>> + /*
>> + * Synchronous aborts may interrupt code which had interrupts masked.
>> + * Before calling out into the wider kernel tell the interested
>> + * subsystems.
>> + */
>> + if (IS_ENABLED(CONFIG_ACPI_APEI_SEA)) {
>> + nmi_enter();
>> + ghes_notify_sea();
>> + nmi_exit();
>> + }
> Well, the other GHES notification methods use a notifier:
> ghes_notify_sci, ghes_notify_nmi. You probably should do that too
> instead of calling straight into a driver from arch code.
I originally had this as a notifier, but Will requested to remove the
notifier. That conversation is here: https://lkml.org/lkml/2017/1/18/1018

Thanks,
Tyler

--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.