x86/microcode/AMD: Apply the patch early on every logical thread
commit e7ad18d1 upstream. Currently, the patch application logic checks whether the revision needs to be applied on each logical CPU (SMT thread). Therefore, on SMT designs where the microcode engine is shared between the two threads, the application happens only on one of them as that is enough to update the shared microcode engine. However, there are microcode patches which do per-thread modification, see Link tag below. Therefore, drop the revision check and try applying on each thread. This is what the BIOS does too so this method is very much tested. Btw, change only the early paths. On the late loading paths, there's no point in doing per-thread modification because if is it some case like in the bugzilla below - removing a CPUID flag - the kernel cannot go and un-use features it has detected are there early. For that, one should use early loading anyway. [ bp: Fixes does not contain the oldest commit which did check for equality but that is good enough. ] Fixes: 8801b3fc ("x86/microcode/AMD: Rework container parsing") Reported-by: Ștefan Talpalaru <stefantalpalaru@yahoo.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Ștefan Talpalaru <stefantalpalaru@yahoo.com> Cc: <stable@vger.kernel.org> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216211 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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