Commit ad0577c3 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: x86: Kill off __ex() and __kvm_handle_fault_on_reboot() 



Remove the __kvm_handle_fault_on_reboot() and __ex() macros now that all
VMX and SVM instructions use asm goto to handle the fault (or in the
case of VMREAD, completely custom logic).  Drop kvm_spurious_fault()'s
asmlinkage annotation as __kvm_handle_fault_on_reboot() was the only
flow that invoked it from assembly code.

Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Like Xu <like.xu.linux@gmail.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20210809173955.1710866-2-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 2fba4fc1

arch/x86/include/asm/kvm_host.h

+1 −24
Original line number Diff line number Diff line
@@ -1811,30 +1811,7 @@ enum { 
#define kvm_arch_vcpu_memslots_id(vcpu) ((vcpu)->arch.hflags & HF_SMM_MASK ? 1 : 0)

#define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, (role).smm)



asmlinkage void kvm_spurious_fault(void);



/*

 * Hardware virtualization extension instructions may fault if a

 * reboot turns off virtualization while processes are running.

 * Usually after catching the fault we just panic; during reboot

 * instead the instruction is ignored.

 */

#define __kvm_handle_fault_on_reboot(insn)				\

	"666: \n\t"							\

	insn "\n\t"							\

	"jmp	668f \n\t"						\

	"667: \n\t"							\

	"1: \n\t"							\

	".pushsection .discard.instr_begin \n\t"			\

	".long 1b - . \n\t"						\

	".popsection \n\t"						\

	"call	kvm_spurious_fault \n\t"				\

	"1: \n\t"							\

	".pushsection .discard.instr_end \n\t"				\

	".long 1b - . \n\t"						\

	".popsection \n\t"						\

	"668: \n\t"							\

	_ASM_EXTABLE(666b, 667b)

void kvm_spurious_fault(void);



#define KVM_ARCH_WANT_MMU_NOTIFIER

arch/x86/kvm/svm/sev.c

+0 −2
Original line number Diff line number Diff line
@@ -28,8 +28,6 @@ 
#include "cpuid.h"

#include "trace.h"



#define __ex(x) __kvm_handle_fault_on_reboot(x)



#ifndef CONFIG_KVM_AMD_SEV

/*

 * When this config is not defined, SEV feature is not supported and APIs in

arch/x86/kvm/svm/svm.c

+0 −2
Original line number Diff line number Diff line
@@ -46,8 +46,6 @@ 
#include "kvm_onhyperv.h"

#include "svm_onhyperv.h"



#define __ex(x) __kvm_handle_fault_on_reboot(x)



MODULE_AUTHOR("Qumranet");

MODULE_LICENSE("GPL");

arch/x86/kvm/vmx/vmx_ops.h

+0 −2
Original line number Diff line number Diff line
@@ -10,8 +10,6 @@ 
#include "evmcs.h"

#include "vmcs.h"



#define __ex(x) __kvm_handle_fault_on_reboot(x)



asmlinkage void vmread_error(unsigned long field, bool fault);

__attribute__((regparm(0))) void vmread_error_trampoline(unsigned long field,

							 bool fault);

arch/x86/kvm/x86.c

+8 −1
Original line number Diff line number Diff line
@@ -486,7 +486,14 @@ int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 
}

EXPORT_SYMBOL_GPL(kvm_set_apic_base);



asmlinkage __visible noinstr void kvm_spurious_fault(void)

/*

 * Handle a fault on a hardware virtualization (VMX or SVM) instruction.

 *

 * Hardware virtualization extension instructions may fault if a reboot turns

 * off virtualization while processes are running.  Usually after catching the

 * fault we just panic; during reboot instead the instruction is ignored.

 */

noinstr void kvm_spurious_fault(void)

{

	/* Fault while not rebooting.  We want the trace. */

	BUG_ON(!kvm_rebooting);