On 27/01/2026 4:00 pm, Jan Beulich wrote:
> On 27.01.2026 15:34, Andrew Cooper wrote:
>> --- a/xen/arch/x86/cpu/microcode/core.c
>> +++ b/xen/arch/x86/cpu/microcode/core.c
>> @@ -760,6 +760,7 @@ static int __init early_microcode_load(struct boot_info
>> *bi)
>> void *data = NULL;
>> size_t size;
>> struct microcode_patch *patch;
>> + struct cpio_data cd;
>> int idx = opt_mod_idx;
>> int rc;
>>
>> @@ -776,7 +777,6 @@ static int __init early_microcode_load(struct boot_info
>> *bi)
>> for ( idx = 0; idx < bi->nr_modules; ++idx )
>> {
>> const struct boot_module *bm = &bi->mods[idx];
>> - struct cpio_data cd;
>>
>> /* Search anything unclaimed or likely to be a CPIO archive. */
>> if ( bm->kind != BOOTMOD_UNKNOWN && bm->kind != BOOTMOD_RAMDISK
>> )
>> @@ -844,6 +844,18 @@ static int __init early_microcode_load(struct boot_info
>> *bi)
>> idx, size);
>> return -ENODEV;
>> }
>> +
>> + /*
>> + * If this blob appears to be a CPIO archive, try interpreting it as
>> + * one. Otherwise treat it as a raw vendor blob.
>> + */
>> + cd = find_cpio_data(ucode_ops.cpio_path, data, size);
>> + if ( cd.data )
>> + {
>> + data = cd.data;
>> + size = cd.size;
>> + }
>> +
>> goto found;
>> }
> Doesn't microcode_init_cache() then need similar adjustment?
Hmm, yes, but we can actually do that by setting opt_scan=1 here and no
other change.
microcode_init_cache() already has the explicit index to look at, so
opt_scan really becomes an "is cpio" flag.
~Andrew
