x86/ucode: Explain what microcode_set_module() does

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>

diff --git a/xen/arch/x86/cpu/microcode/core.c b/xen/arch/x86/cpu/microcode/core.c
index 1e5fdd02e4617c460af702f7d156bae433095565..2a4c65744fe002f9edd529d83f94e47f861b47c6 100644 (file)
--- a/xen/arch/x86/cpu/microcode/core.c
+++ b/xen/arch/x86/cpu/microcode/core.c
@@ -109,6 +109,10 @@ static bool ucode_in_nmi = true;
 /* Protected by microcode_mutex */
 static const struct microcode_patch *microcode_cache;
 
+/*
+ * Used by the EFI path only, when xen.cfg identifies an explicit microcode
+ * file.  Overrides ucode=<int>|scan on the regular command line.
+ */
 void __init microcode_set_module(unsigned int idx)
 {
     ucode_mod_idx = idx;