mirror of https://gitee.com/openkylin/linux.git
x86/kvm/svm: Move guest enter/exit into .noinstr.text
Move the functions which are inside the RCU off region into the non-instrumentable text section. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20200708195322.144607767@linutronix.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Thomas Gleixner
Paolo Bonzini
parent
3ebccdf373
commit
135961e0a7
|
|
@ -3343,6 +3343,60 @@ static fastpath_t svm_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
|
||||||
|
|
||||||
void __svm_vcpu_run(unsigned long vmcb_pa, unsigned long *regs);
|
void __svm_vcpu_run(unsigned long vmcb_pa, unsigned long *regs);
|
||||||
|
|
||||||
|
static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu,
|
||||||
|
struct vcpu_svm *svm)
|
||||||
|
{
|
||||||
|
/*
|
||||||
|
* VMENTER enables interrupts (host state), but the kernel state is
|
||||||
|
* interrupts disabled when this is invoked. Also tell RCU about
|
||||||
|
* it. This is the same logic as for exit_to_user_mode().
|
||||||
|
*
|
||||||
|
* This ensures that e.g. latency analysis on the host observes
|
||||||
|
* guest mode as interrupt enabled.
|
||||||
|
*
|
||||||
|
* guest_enter_irqoff() informs context tracking about the
|
||||||
|
* transition to guest mode and if enabled adjusts RCU state
|
||||||
|
* accordingly.
|
||||||
|
*/
|
||||||
|
instrumentation_begin();
|
||||||
|
trace_hardirqs_on_prepare();
|
||||||
|
lockdep_hardirqs_on_prepare(CALLER_ADDR0);
|
||||||
|
instrumentation_end();
|
||||||
|
|
||||||
|
guest_enter_irqoff();
|
||||||
|
lockdep_hardirqs_on(CALLER_ADDR0);
|
||||||
|
|
||||||
|
__svm_vcpu_run(svm->vmcb_pa, (unsigned long *)&svm->vcpu.arch.regs);
|
||||||
|
|
||||||
|
#ifdef CONFIG_X86_64
|
||||||
|
wrmsrl(MSR_GS_BASE, svm->host.gs_base);
|
||||||
|
#else
|
||||||
|
loadsegment(fs, svm->host.fs);
|
||||||
|
#ifndef CONFIG_X86_32_LAZY_GS
|
||||||
|
loadsegment(gs, svm->host.gs);
|
||||||
|
#endif
|
||||||
|
#endif
|
||||||
|
|
||||||
|
/*
|
||||||
|
* VMEXIT disables interrupts (host state), but tracing and lockdep
|
||||||
|
* have them in state 'on' as recorded before entering guest mode.
|
||||||
|
* Same as enter_from_user_mode().
|
||||||
|
*
|
||||||
|
* guest_exit_irqoff() restores host context and reinstates RCU if
|
||||||
|
* enabled and required.
|
||||||
|
*
|
||||||
|
* This needs to be done before the below as native_read_msr()
|
||||||
|
* contains a tracepoint and x86_spec_ctrl_restore_host() calls
|
||||||
|
* into world and some more.
|
||||||
|
*/
|
||||||
|
lockdep_hardirqs_off(CALLER_ADDR0);
|
||||||
|
guest_exit_irqoff();
|
||||||
|
|
||||||
|
instrumentation_begin();
|
||||||
|
trace_hardirqs_off_finish();
|
||||||
|
instrumentation_end();
|
||||||
|
}
|
||||||
|
|
||||||
static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
|
static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
|
||||||
{
|
{
|
||||||
fastpath_t exit_fastpath;
|
fastpath_t exit_fastpath;
|
||||||
|
|
@ -3398,49 +3452,7 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
|
||||||
*/
|
*/
|
||||||
x86_spec_ctrl_set_guest(svm->spec_ctrl, svm->virt_spec_ctrl);
|
x86_spec_ctrl_set_guest(svm->spec_ctrl, svm->virt_spec_ctrl);
|
||||||
|
|
||||||
/*
|
svm_vcpu_enter_exit(vcpu, svm);
|
||||||
* VMENTER enables interrupts (host state), but the kernel state is
|
|
||||||
* interrupts disabled when this is invoked. Also tell RCU about
|
|
||||||
* it. This is the same logic as for exit_to_user_mode().
|
|
||||||
*
|
|
||||||
* This ensures that e.g. latency analysis on the host observes
|
|
||||||
* guest mode as interrupt enabled.
|
|
||||||
*
|
|
||||||
* guest_enter_irqoff() informs context tracking about the
|
|
||||||
* transition to guest mode and if enabled adjusts RCU state
|
|
||||||
* accordingly.
|
|
||||||
*/
|
|
||||||
trace_hardirqs_on_prepare();
|
|
||||||
lockdep_hardirqs_on_prepare(CALLER_ADDR0);
|
|
||||||
guest_enter_irqoff();
|
|
||||||
lockdep_hardirqs_on(CALLER_ADDR0);
|
|
||||||
|
|
||||||
__svm_vcpu_run(svm->vmcb_pa, (unsigned long *)&svm->vcpu.arch.regs);
|
|
||||||
|
|
||||||
#ifdef CONFIG_X86_64
|
|
||||||
wrmsrl(MSR_GS_BASE, svm->host.gs_base);
|
|
||||||
#else
|
|
||||||
loadsegment(fs, svm->host.fs);
|
|
||||||
#ifndef CONFIG_X86_32_LAZY_GS
|
|
||||||
loadsegment(gs, svm->host.gs);
|
|
||||||
#endif
|
|
||||||
#endif
|
|
||||||
|
|
||||||
/*
|
|
||||||
* VMEXIT disables interrupts (host state), but tracing and lockdep
|
|
||||||
* have them in state 'on' as recorded before entering guest mode.
|
|
||||||
* Same as enter_from_user_mode().
|
|
||||||
*
|
|
||||||
* guest_exit_irqoff() restores host context and reinstates RCU if
|
|
||||||
* enabled and required.
|
|
||||||
*
|
|
||||||
* This needs to be done before the below as native_read_msr()
|
|
||||||
* contains a tracepoint and x86_spec_ctrl_restore_host() calls
|
|
||||||
* into world and some more.
|
|
||||||
*/
|
|
||||||
lockdep_hardirqs_off(CALLER_ADDR0);
|
|
||||||
guest_exit_irqoff();
|
|
||||||
trace_hardirqs_off_finish();
|
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* We do not use IBRS in the kernel. If this vCPU has used the
|
* We do not use IBRS in the kernel. If this vCPU has used the
|
||||||
|
|
|
||||||
|
|
@ -27,7 +27,7 @@
|
||||||
#define VCPU_R15 __VCPU_REGS_R15 * WORD_SIZE
|
#define VCPU_R15 __VCPU_REGS_R15 * WORD_SIZE
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
.text
|
.section .noinstr.text, "ax"
|
||||||
|
|
||||||
/**
|
/**
|
||||||
* __svm_vcpu_run - Run a vCPU via a transition to SVM guest mode
|
* __svm_vcpu_run - Run a vCPU via a transition to SVM guest mode
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue