From 9f15226e75583547aaf542c6be4bdac1060dd425 Mon Sep 17 00:00:00 2001 From: Andreas Herrmann Date: Wed, 11 Nov 2009 20:03:29 +0100 Subject: [PATCH] x86, ucode-amd: Ensure ucode update on suspend/resume after CPU off/online cycle When switching a CPU offline/online and then doing suspend/resume, ucode is not updated on this CPU. This is due to the microcode_fini_cpu() call which frees uci->mc when setting the CPU offline: static void microcode_fini_cpu_amd(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; vfree(uci->mc); uci->mc = NULL; } When the CPU is set online uci->mc is still NULL because no ucode update is required. Finally this prevents ucode update when resuming after suspend: static enum ucode_state microcode_resume_cpu(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; if (!uci->mc) return UCODE_NFOUND; ... } Fix is to check whether uci->mc is valid before microcode_resume_cpu() is called. Signed-off-by: Andreas Herrmann Cc: dimm LKML-Reference: <20091111190329.GF18592@alberich.amd.com> Signed-off-by: Ingo Molnar --- arch/x86/kernel/microcode_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c index d2a816021d9..adf23406154 100644 --- a/arch/x86/kernel/microcode_core.c +++ b/arch/x86/kernel/microcode_core.c @@ -393,7 +393,7 @@ static enum ucode_state microcode_update_cpu(int cpu) struct ucode_cpu_info *uci = ucode_cpu_info + cpu; enum ucode_state ustate; - if (uci->valid) + if (uci->valid && uci->mc) ustate = microcode_resume_cpu(cpu); else ustate = microcode_init_cpu(cpu);