[PATCH] x86/ucode: Explain what microcode_set_module() does

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Jan Beulich <JBeulich@xxxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>

I found this hiding in other microcode changes, and decided it was high time
it got included.
---
 xen/arch/x86/cpu/microcode/core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/xen/arch/x86/cpu/microcode/core.c 
b/xen/arch/x86/cpu/microcode/core.c
index 8564e4d2c94c..dc2c064cf176 100644
--- a/xen/arch/x86/cpu/microcode/core.c
+++ b/xen/arch/x86/cpu/microcode/core.c
@@ -108,6 +108,10 @@ 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;

base-commit: be84e7fe58b51f6b6dd907a038f0ef998a1e281e
prerequisite-patch-id: ef20898eb25a7ca1ea2d7b1d676f00b91b46d5f6
prerequisite-patch-id: e0d0c0acbe4864a00451187ef7232dcaf10b2477
prerequisite-patch-id: f6010b4a6e0b43ac837aea470b3b5e5f390ee3b2
-- 
2.39.5