From 370a132bb2227ff76278f98370e0e701d86ff752 Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Tue, 31 Jul 2018 07:27:39 -0400 Subject: x86/microcode: Make sure boot_cpu_data.microcode is up-to-date When preparing an MCE record for logging, boot_cpu_data.microcode is used to read out the microcode revision on the box. However, on systems where late microcode update has happened, the microcode revision output in a MCE log record is wrong because boot_cpu_data.microcode is not updated when the microcode gets updated. But, the microcode revision saved in boot_cpu_data's microcode member should be kept up-to-date, regardless, for consistency. Make it so. Fixes: fa94d0c6e0f3 ("x86/MCE: Save microcode revision in machine check records") Signed-off-by: Prarit Bhargava Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: Tony Luck Cc: sironi@amazon.de Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180731112739.32338-1-prarit@redhat.com --- arch/x86/kernel/cpu/microcode/intel.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/x86/kernel/cpu/microcode/intel.c') diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c index 97ccf4c3b45b..256d336cbc04 100644 --- a/arch/x86/kernel/cpu/microcode/intel.c +++ b/arch/x86/kernel/cpu/microcode/intel.c @@ -851,6 +851,10 @@ static enum ucode_state apply_microcode_intel(int cpu) uci->cpu_sig.rev = rev; c->microcode = rev; + /* Update boot_cpu_data's revision too, if we're on the BSP: */ + if (c->cpu_index == boot_cpu_data.cpu_index) + boot_cpu_data.microcode = rev; + return UCODE_UPDATED; } -- cgit From 8da38ebaad23fe1b0c4a205438676f6356607cfc Mon Sep 17 00:00:00 2001 From: Filippo Sironi Date: Tue, 31 Jul 2018 17:29:30 +0200 Subject: x86/microcode: Update the new microcode revision unconditionally Handle the case where microcode gets loaded on the BSP's hyperthread sibling first and the boot_cpu_data's microcode revision doesn't get updated because of early exit due to the siblings sharing a microcode engine. For that, simply write the updated revision on all CPUs unconditionally. Signed-off-by: Filippo Sironi Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: prarit@redhat.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1533050970-14385-1-git-send-email-sironi@amazon.de --- arch/x86/kernel/cpu/microcode/intel.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'arch/x86/kernel/cpu/microcode/intel.c') diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c index 256d336cbc04..16936a24795c 100644 --- a/arch/x86/kernel/cpu/microcode/intel.c +++ b/arch/x86/kernel/cpu/microcode/intel.c @@ -795,6 +795,7 @@ static enum ucode_state apply_microcode_intel(int cpu) struct ucode_cpu_info *uci = ucode_cpu_info + cpu; struct cpuinfo_x86 *c = &cpu_data(cpu); struct microcode_intel *mc; + enum ucode_state ret; static int prev_rev; u32 rev; @@ -817,9 +818,8 @@ static enum ucode_state apply_microcode_intel(int cpu) */ rev = intel_get_microcode_revision(); if (rev >= mc->hdr.rev) { - uci->cpu_sig.rev = rev; - c->microcode = rev; - return UCODE_OK; + ret = UCODE_OK; + goto out; } /* @@ -848,14 +848,17 @@ static enum ucode_state apply_microcode_intel(int cpu) prev_rev = rev; } + ret = UCODE_UPDATED; + +out: uci->cpu_sig.rev = rev; - c->microcode = rev; + c->microcode = rev; /* Update boot_cpu_data's revision too, if we're on the BSP: */ if (c->cpu_index == boot_cpu_data.cpu_index) boot_cpu_data.microcode = rev; - return UCODE_UPDATED; + return ret; } static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size, -- cgit