diff options
| author |   David Woodhouse <dwmw@amazon.co.uk> | 2018-01-11 21:46:26 +0000 |
|---|---|---|
| committer |   Thomas Gleixner <tglx@linutronix.de> | 2018-01-12 00:14:29 +0100 |
| commit | da285121560e769cc31797bba6422eea71d473e0 (patch) | |
| tree | c28344795834b8449fc63bb22c9d2a6c50edfe6c /arch/x86/kernel/cpu/common.c | |
| parent | x86/retpoline: Add initial retpoline support (diff) | |
| download | linux-dev-da285121560e769cc31797bba6422eea71d473e0.tar.xz linux-dev-da285121560e769cc31797bba6422eea71d473e0.zip | |
x86/spectre: Add boot time option to select Spectre v2 mitigation
Add a spectre_v2= option to select the mitigation used for the indirect
branch speculation vulnerability.
Currently, the only option available is retpoline, in its various forms.
This will be expanded to cover the new IBRS/IBPB microcode features.
The RETPOLINE_AMD feature relies on a serializing LFENCE for speculation
control. For AMD hardware, only set RETPOLINE_AMD if LFENCE is a
serializing instruction, which is indicated by the LFENCE_RDTSC feature.
[ tglx: Folded back the LFENCE/AMD fixes and reworked it so IBRS
integration becomes simple ]
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-5-git-send-email-dwmw@amazon.co.uk
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 4 |
1 files changed, 0 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 7a671d1ae3cb..372ba3fb400f 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -905,10 +905,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c) setup_force_cpu_bug(X86_BUG_SPECTRE_V1); setup_force_cpu_bug(X86_BUG_SPECTRE_V2); -#ifdef CONFIG_RETPOLINE - setup_force_cpu_cap(X86_FEATURE_RETPOLINE); -#endif - fpu__init_system(c); #ifdef CONFIG_X86_32 |