This is a note to let you know that I've just added the patch titled x86/cpufeatures: Make CPU bugs sticky to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-cpufeatures-make-cpu-bugs-sticky.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 6cbd2171e89b13377261d15e64384df60ecb530e Mon Sep 17 00:00:00 2001 From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Date: Mon, 4 Dec 2017 15:07:32 +0100 Subject: x86/cpufeatures: Make CPU bugs sticky From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> commit 6cbd2171e89b13377261d15e64384df60ecb530e upstream. There is currently no way to force CPU bug bits like CPU feature bits. That makes it impossible to set a bug bit once at boot and have it stick for all upcoming CPUs. Extend the force set/clear arrays to handle bug bits as well. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reviewed-by: Borislav Petkov <bp@xxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Borislav Petkov <bpetkov@xxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: David Laight <David.Laight@xxxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: Eduardo Valentin <eduval@xxxxxxxxxx> Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Cc: Juergen Gross <jgross@xxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: aliguori@xxxxxxxxxx Cc: daniel.gruss@xxxxxxxxxxxxxx Cc: hughd@xxxxxxxxxx Cc: keescook@xxxxxxxxxx Link: https://lkml.kernel.org/r/20171204150606.992156574@xxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/include/asm/cpufeature.h | 2 ++ arch/x86/include/asm/processor.h | 4 ++-- arch/x86/kernel/cpu/common.c | 6 +++--- 3 files changed, 7 insertions(+), 5 deletions(-) --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -359,6 +359,8 @@ extern const char * const x86_bug_flags[ set_bit(bit, (unsigned long *)cpu_caps_set); \ } while (0) +#define setup_force_cpu_bug(bit) setup_force_cpu_cap(bit) + #define cpu_has_fpu boot_cpu_has(X86_FEATURE_FPU) #define cpu_has_de boot_cpu_has(X86_FEATURE_DE) #define cpu_has_pse boot_cpu_has(X86_FEATURE_PSE) --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -156,8 +156,8 @@ extern struct cpuinfo_x86 boot_cpu_data; extern struct cpuinfo_x86 new_cpu_data; extern struct tss_struct doublefault_tss; -extern __u32 cpu_caps_cleared[NCAPINTS]; -extern __u32 cpu_caps_set[NCAPINTS]; +extern __u32 cpu_caps_cleared[NCAPINTS + NBUGINTS]; +extern __u32 cpu_caps_set[NCAPINTS + NBUGINTS]; #ifdef CONFIG_SMP DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info); --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -432,8 +432,8 @@ static const char *table_lookup_model(st return NULL; /* Not found */ } -__u32 cpu_caps_cleared[NCAPINTS]; -__u32 cpu_caps_set[NCAPINTS]; +__u32 cpu_caps_cleared[NCAPINTS + NBUGINTS]; +__u32 cpu_caps_set[NCAPINTS + NBUGINTS]; void load_percpu_segment(int cpu) { @@ -668,7 +668,7 @@ static void apply_forced_caps(struct cpu { int i; - for (i = 0; i < NCAPINTS; i++) { + for (i = 0; i < NCAPINTS + NBUGINTS; i++) { c->x86_capability[i] &= ~cpu_caps_cleared[i]; c->x86_capability[i] |= cpu_caps_set[i]; } Patches currently in stable-queue which might be from tglx@xxxxxxxxxxxxx are queue-4.4/x86-mm-pat-dev-mem-remove-superfluous-error-message.patch queue-4.4/x86-cpufeatures-add-x86_bug_spectre_v.patch queue-4.4/x86-microcode-intel-extend-bdw-late-loading-with-a-revision-check.patch queue-4.4/x86-alternatives-add-missing-n-at-end-of-alternative-inline-asm.patch queue-4.4/sysfs-cpu-fix-typos-in-vulnerability-documentation.patch queue-4.4/locking-mutex-allow-next-waiter-lockless-wakeup.patch queue-4.4/x86-cpufeatures-add-x86_bug_cpu_insecure.patch queue-4.4/x86-cpufeatures-make-cpu-bugs-sticky.patch queue-4.4/x86-vsdo-fix-build-on-paravirt_clock-y-kvm_guest-n.patch queue-4.4/x86-pti-efi-broken-conversion-from-efi-to-kernel-page-table.patch queue-4.4/x86-documentation-add-pti-description.patch queue-4.4/x86-acpi-handle-sci-interrupts-above-legacy-space-gracefully.patch queue-4.4/x86-cpu-implement-cpu-vulnerabilites-sysfs-functions.patch queue-4.4/futex-replace-barrier-in-unqueue_me-with-read_once.patch queue-4.4/x86-cpu-factor-out-application-of-forced-cpu-caps.patch queue-4.4/selftests-x86-add-test_vsyscall.patch queue-4.4/x86-cpu-merge-bugs.c-and-bugs_64.c.patch queue-4.4/sysfs-cpu-add-vulnerability-folder.patch queue-4.4/x86-pti-rename-bug_cpu_insecure-to-bug_cpu_meltdown.patch queue-4.4/x86-acpi-reduce-code-duplication-in-mp_override_legacy_irq.patch queue-4.4/x86-alternatives-fix-optimize_nops-checking.patch