On 4/5/19 6:57 AM, Borislav Petkov wrote: > On Thu, Apr 04, 2019 at 11:44:12AM -0500, Josh Poimboeuf wrote: >> Configure x86 runtime CPU speculation bug mitigations in accordance with >> the 'cpu_spec_mitigations=' cmdline options. This affects Meltdown, >> Spectre v2, Speculative Store Bypass, and L1TF. >> >> The default behavior is unchanged. >> >> Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> >> --- >> .../admin-guide/kernel-parameters.txt | 15 +++++++++ >> arch/x86/include/asm/processor.h | 1 + >> arch/x86/kernel/cpu/bugs.c | 32 ++++++++++++++++--- >> arch/x86/kvm/vmx/vmx.c | 2 ++ >> arch/x86/mm/pti.c | 4 ++- >> 5 files changed, 49 insertions(+), 5 deletions(-) >> >> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >> index ac42e510bd6e..29dc03971630 100644 >> --- a/Documentation/admin-guide/kernel-parameters.txt >> +++ b/Documentation/admin-guide/kernel-parameters.txt >> @@ -2552,6 +2552,11 @@ >> >> off >> Disable all speculative CPU mitigations. >> + Equivalent to: nopti [x86] >> + nospectre_v2 [x86] >> + spectre_v2_user=off [x86] >> + spec_store_bypass_disable=off [x86] >> + l1tf=off [x86] >> >> auto (default) >> Mitigate all speculative CPU vulnerabilities, >> @@ -2560,12 +2565,22 @@ >> surprised by SMT getting disabled across kernel >> upgrades, or who have other ways of avoiding >> SMT-based attacks. >> + Equivalent to: pti=auto [x86] >> + spectre_v2=auto [x86] >> + spectre_v2_user=auto [x86] >> + spec_store_bypass_disable=auto [x86] >> + l1tf=flush [x86] >> >> auto,nosmt >> Mitigate all speculative CPU vulnerabilities, >> disabling SMT if needed. This is for users who >> always want to be fully mitigated, even if it >> means losing SMT. >> + Equivalent to: pti=auto [x86] >> + spectre_v2=auto [x86] >> + spectre_v2_user=auto [x86] >> + spec_store_bypass_disable=auto [x86] >> + l1tf=flush,nosmt [x86] >> >> mminit_loglevel= >> [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this > > Yap, those sets look ok. nit: s/x86/X86/g according to Documentation/admin-guide/kernel-parameters.rst -- ~Randy
