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Subject[PATCH] x86/microcode/AMD: Document which patches are not released for late loading
Date
From: "Borislav Petkov (AMD)" <bp@alien8.de>

PeterZ wanted this spelled out explicitly. Add it to the documentation
so that everyone's on the same page wrt to which microcode patches are
not allowed to be late loaded.

Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
---
Documentation/x86/microcode.rst | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/Documentation/x86/microcode.rst b/Documentation/x86/microcode.rst
index 15b52e2b181d..d5ef9184030c 100644
--- a/Documentation/x86/microcode.rst
+++ b/Documentation/x86/microcode.rst
@@ -218,6 +218,10 @@ a fault happens, the whole core will see it either before the microcode
patch has been applied or after. In either case, T0 and T1 will have the
same microcode revision and nothing intermediate.

+In addition, microcode patches which modify software-visible features
+like CPUID bits, MSRs, chicken bits, etc are not released for late
+loading.
+
Builtin microcode
=================

--
2.35.1
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