From fb86b97300d930b57471068720c52bfa8622eab7 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Tue, 18 Nov 2014 10:46:57 +0100 Subject: [PATCH] x86, microcode: Update BSPs microcode on resume In the situation when we apply early microcode but do *not* apply late microcode, we fail to update the BSP's microcode on resume because we haven't initialized the uci->mc microcode pointer. So, in order to alleviate that, we go and dig out the stashed microcode patch during early boot. It is basically the same thing that is done on the APs early during boot so do that too here. Tested-by: alex.schnaidt@gmail.com Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=88001 Cc: Henrique de Moraes Holschuh Cc: Fenghua Yu Cc: # v3.9 Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/20141118094657.GA6635@pd.tnic Signed-off-by: Thomas Gleixner --- arch/x86/kernel/cpu/microcode/core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index dd9d6190b08d..2ce9051174e6 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -465,6 +465,14 @@ static void mc_bp_resume(void) if (uci->valid && uci->mc) microcode_ops->apply_microcode(cpu); + else if (!uci->mc) + /* + * We might resume and not have applied late microcode but still + * have a newer patch stashed from the early loader. We don't + * have it in uci->mc so we have to load it the same way we're + * applying patches early on the APs. + */ + load_ucode_ap(); } static struct syscore_ops mc_syscore_ops = { -- 2.34.1