x86: asm/virtext.h: add cpu_vmxoff() inline function

Unfortunately we can't use exactly the same code from vmx
hardware_disable(), because the KVM function uses the
__kvm_handle_fault_on_reboot() tricks.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Eduardo Habkost 2008-11-17 19:03:17 -02:00 committed by Avi Kivity
parent 6210e37b12
commit 1e9931146c
1 changed files with 15 additions and 0 deletions

View File

@ -18,6 +18,8 @@
#include <asm/processor.h> #include <asm/processor.h>
#include <asm/system.h> #include <asm/system.h>
#include <asm/vmx.h>
/* /*
* VMX functions: * VMX functions:
*/ */
@ -28,4 +30,17 @@ static inline int cpu_has_vmx(void)
return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */ return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */
} }
/** Disable VMX on the current CPU
*
* vmxoff causes a undefined-opcode exception if vmxon was not run
* on the CPU previously. Only call this function if you know VMX
* is enabled.
*/
static inline void cpu_vmxoff(void)
{
asm volatile (ASM_VMX_VMXOFF : : : "cc");
write_cr4(read_cr4() & ~X86_CR4_VMXE);
}
#endif /* _ASM_X86_VIRTEX_H */ #endif /* _ASM_X86_VIRTEX_H */