4.13-stable review patch. If anyone has any objections, please let me know.
------------------ From: Borislav Petkov <b...@suse.de> commit 723f2828a98c8ca19842042f418fb30dd8cfc0f7 upstream. Blacklist Broadwell X model 79 for late loading due to an erratum. Signed-off-by: Borislav Petkov <b...@suse.de> Acked-by: Tony Luck <tony.l...@intel.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/20171018111225.25635-1...@alien8.de Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/x86/kernel/cpu/microcode/intel.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- a/arch/x86/kernel/cpu/microcode/intel.c +++ b/arch/x86/kernel/cpu/microcode/intel.c @@ -34,6 +34,7 @@ #include <linux/mm.h> #include <asm/microcode_intel.h> +#include <asm/intel-family.h> #include <asm/processor.h> #include <asm/tlbflush.h> #include <asm/setup.h> @@ -917,6 +918,18 @@ static int get_ucode_fw(void *to, const return 0; } +static bool is_blacklisted(unsigned int cpu) +{ + struct cpuinfo_x86 *c = &cpu_data(cpu); + + if (c->x86 == 6 && c->x86_model == INTEL_FAM6_BROADWELL_X) { + pr_err_once("late loading on model 79 is disabled.\n"); + return true; + } + + return false; +} + static enum ucode_state request_microcode_fw(int cpu, struct device *device, bool refresh_fw) { @@ -925,6 +938,9 @@ static enum ucode_state request_microcod const struct firmware *firmware; enum ucode_state ret; + if (is_blacklisted(cpu)) + return UCODE_NFOUND; + sprintf(name, "intel-ucode/%02x-%02x-%02x", c->x86, c->x86_model, c->x86_mask); @@ -949,6 +965,9 @@ static int get_ucode_user(void *to, cons static enum ucode_state request_microcode_user(int cpu, const void __user *buf, size_t size) { + if (is_blacklisted(cpu)) + return UCODE_NFOUND; + return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user); }
