diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-01-29 19:08:02 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-01-29 19:08:02 -0800 |
commit | 6304672b7f0a5c010002e63a075160856dc4f88d (patch) | |
tree | 3f2d7fbaa9fe998787fa474c63fb1e6aa98090ab /arch/x86/kvm | |
parent | 942633523cde99c5bfa0329996dd839ca66a87aa (diff) | |
parent | 64e16720ea0879f8ab4547e3b9758936d483909b (diff) |
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/pti updates from Thomas Gleixner:
"Another set of melted spectrum related changes:
- Code simplifications and cleanups for RSB and retpolines.
- Make the indirect calls in KVM speculation safe.
- Whitelist CPUs which are known not to speculate from Meltdown and
prepare for the new CPUID flag which tells the kernel that a CPU is
not affected.
- A less rigorous variant of the module retpoline check which merily
warns when a non-retpoline protected module is loaded and reflects
that fact in the sysfs file.
- Prepare for Indirect Branch Prediction Barrier support.
- Prepare for exposure of the Speculation Control MSRs to guests, so
guest OSes which depend on those "features" can use them. Includes
a blacklist of the broken microcodes. The actual exposure of the
MSRs through KVM is still being worked on"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Simplify indirect_branch_prediction_barrier()
x86/retpoline: Simplify vmexit_fill_RSB()
x86/cpufeatures: Clean up Spectre v2 related CPUID flags
x86/cpu/bugs: Make retpoline module warning conditional
x86/bugs: Drop one "mitigation" from dmesg
x86/nospec: Fix header guards names
x86/alternative: Print unadorned pointers
x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes
x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
x86/msr: Add definitions for new speculation control MSRs
x86/cpufeatures: Add AMD feature bits for Speculation Control
x86/cpufeatures: Add Intel feature bits for Speculation Control
x86/cpufeatures: Add CPUID_7_EDX CPUID leaf
module/retpoline: Warn about missing retpoline in module
KVM: VMX: Make indirect call speculation safe
KVM: x86: Make indirect calls in emulator speculation safe
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r-- | arch/x86/kvm/emulate.c | 9 | ||||
-rw-r--r-- | arch/x86/kvm/vmx.c | 4 |
2 files changed, 7 insertions, 6 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index b514b2b2845a..290ecf711aec 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -25,6 +25,7 @@ #include <asm/kvm_emulate.h> #include <linux/stringify.h> #include <asm/debugreg.h> +#include <asm/nospec-branch.h> #include "x86.h" #include "tss.h" @@ -1021,8 +1022,8 @@ static __always_inline u8 test_cc(unsigned int condition, unsigned long flags) void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf); flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF; - asm("push %[flags]; popf; call *%[fastop]" - : "=a"(rc) : [fastop]"r"(fop), [flags]"r"(flags)); + asm("push %[flags]; popf; " CALL_NOSPEC + : "=a"(rc) : [thunk_target]"r"(fop), [flags]"r"(flags)); return rc; } @@ -5335,9 +5336,9 @@ static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)) if (!(ctxt->d & ByteOp)) fop += __ffs(ctxt->dst.bytes) * FASTOP_SIZE; - asm("push %[flags]; popf; call *%[fastop]; pushf; pop %[flags]\n" + asm("push %[flags]; popf; " CALL_NOSPEC " ; pushf; pop %[flags]\n" : "+a"(ctxt->dst.val), "+d"(ctxt->src.val), [flags]"+D"(flags), - [fastop]"+S"(fop), ASM_CALL_CONSTRAINT + [thunk_target]"+S"(fop), ASM_CALL_CONSTRAINT : "c"(ctxt->src2.val)); ctxt->eflags = (ctxt->eflags & ~EFLAGS_MASK) | (flags & EFLAGS_MASK); diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index c829d89e2e63..a8b96dc4cd83 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -9129,14 +9129,14 @@ static void vmx_handle_external_intr(struct kvm_vcpu *vcpu) #endif "pushf\n\t" __ASM_SIZE(push) " $%c[cs]\n\t" - "call *%[entry]\n\t" + CALL_NOSPEC : #ifdef CONFIG_X86_64 [sp]"=&r"(tmp), #endif ASM_CALL_CONSTRAINT : - [entry]"r"(entry), + THUNK_TARGET(entry), [ss]"i"(__KERNEL_DS), [cs]"i"(__KERNEL_CS) ); |