The EINJv2 set_error_type_with_address structure has a flex array to hold the component IDs and syndrome values used when injecting multiple errors at once.
Discover the size of this array by taking the address from the ACPI_EINJ_SET_ERROR_TYPE_WITH_ADDRESS entry in the EINJ table and reading the BIOS copy of the structure. Derive the maximum number of components from the length field in the einjv2_extension_struct at the end of the BIOS copy. Map the whole of the structure into kernel memory (and unmap on module unload). [Tony: Code unchanged from Zaid's original. New commit message] Reviewed-by: Tony Luck <[email protected]> Signed-off-by: Zaid Alali <[email protected]> --- drivers/acpi/apei/einj-core.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/apei/einj-core.c b/drivers/acpi/apei/einj-core.c index e74281f5044e..08cac48293a2 100644 --- a/drivers/acpi/apei/einj-core.c +++ b/drivers/acpi/apei/einj-core.c @@ -107,6 +107,7 @@ static struct debugfs_blob_wrapper vendor_blob; static struct debugfs_blob_wrapper vendor_errors; static char vendor_dev[64]; +static u32 max_nr_components; static u32 available_error_type; static u32 available_error_type_v2; @@ -177,6 +178,7 @@ static DEFINE_MUTEX(einj_mutex); bool einj_initialized __ro_after_init; static void __iomem *einj_param; +static u32 v5param_size; static void einj_exec_ctx_init(struct apei_exec_context *ctx) { @@ -301,11 +303,31 @@ static void __iomem *einj_get_parameter_address(void) struct set_error_type_with_address v5param; struct set_error_type_with_address __iomem *p; + v5param_size = sizeof(v5param); p = acpi_os_map_iomem(pa_v5, sizeof(*p)); if (p) { - memcpy_fromio(&v5param, p, sizeof(v5param)); + int offset, len; + + memcpy_fromio(&v5param, p, v5param_size); acpi5 = 1; check_vendor_extension(pa_v5, &v5param); + if (available_error_type & ACPI65_EINJV2_SUPP) { + len = v5param.einjv2_struct.length; + offset = offsetof(struct einjv2_extension_struct, component_arr); + max_nr_components = (len - offset) / + sizeof(v5param.einjv2_struct.component_arr[0]); + /* + * The first call to acpi_os_map_iomem above does not include the + * component array, instead it is used to read and calculate maximum + * number of components supported by the system. Below, the mapping + * is expanded to include the component array. + */ + acpi_os_unmap_iomem(p, v5param_size); + offset = offsetof(struct set_error_type_with_address, einjv2_struct); + v5param_size = offset + struct_size(&v5param.einjv2_struct, + component_arr, max_nr_components); + p = acpi_os_map_iomem(pa_v5, v5param_size); + } return p; } } @@ -932,7 +954,7 @@ static void __exit einj_remove(struct faux_device *fdev) if (einj_param) { acpi_size size = (acpi5) ? - sizeof(struct set_error_type_with_address) : + v5param_size : sizeof(struct einj_parameter); acpi_os_unmap_iomem(einj_param, size); -- 2.43.0
