On Tue, Nov 07, 2023 at 03:36:47PM -0600, Avadhut Naik wrote:
> From: Avadhut Naik <Avadhut.Naik@xxxxxxx>
>
> Vendor-Defined Error types are supported by the platform apart from
> standard error types if bit 31 is set in the output of GET_ERROR_TYPE
> Error Injection Action.[1] While the errors themselves and the length
> of their associated "OEM Defined data structure" might vary between
> vendors, the physical address of this structure can be computed through
> vendor_extension and length fields of "SET_ERROR_TYPE_WITH_ADDRESS" and
> "Vendor Error Type Extension" Structures respectively.[2][3]
>
> Currently, however, the einj module only computes the physical address of
> Vendor Error Type Extension Structure. Neither does it compute the physical
> address of OEM Defined structure nor does it establish the memory mapping
> required for injecting Vendor-defined errors. Consequently, userspace
> tools have to establish the very mapping through /dev/mem, nopat kernel
> parameter and system calls like mmap/munmap initially before injecting
> Vendor-defined errors.
>
> Circumvent the issue by computing the physical address of OEM Defined data
> structure and establishing the required mapping with the structure. Create
> a new file "oem_error", if the system supports Vendor-defined errors, to
> export this mapping, through debugfs_create_blob(). Userspace tools can
> then populate their respective OEM Defined structure instances and just
> write to the file as part of injecting Vendor-defined Errors. Similarly,
> the tools can also read from the file if the system firmware provides some
> information through the OEM defined structure after error injection.
>
> [1] ACPI specification 6.5, section 18.6.4
> [2] ACPI specification 6.5, Table 18.31
> [3] ACPI specification 6.5, Table 18.32
>
> Suggested-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
> Signed-off-by: Avadhut Naik <Avadhut.Naik@xxxxxxx>
> ---
> drivers/acpi/apei/einj.c | 24 ++++++++++++++++++++++++
> 1 file changed, 24 insertions(+)
Reviewed-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
