Commit 8eb9a48a authored by Kevin Tian's avatar Kevin Tian Committed by Paolo Bonzini
Browse files

x86/fpu: Provide fpu_update_guest_xfd() for IA32_XFD emulation 



Guest XFD can be updated either in the emulation path or in the
restore path.

Provide a wrapper to update guest_fpu::fpstate::xfd. If the guest
fpstate is currently in-use, also update the per-cpu xfd cache and
the actual MSR.

Signed-off-by: default avatarKevin Tian <kevin.tian@intel.com>
Signed-off-by: default avatarJing Liu <jing2.liu@intel.com>
Signed-off-by: default avatarYang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-10-yang.zhong@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 5ab2f45b

arch/x86/include/asm/fpu/api.h

+6 −0
Original line number Diff line number Diff line
@@ -140,6 +140,12 @@ extern void fpu_free_guest_fpstate(struct fpu_guest *gfpu); 
extern int fpu_swap_kvm_fpstate(struct fpu_guest *gfpu, bool enter_guest);

extern int fpu_enable_guest_xfd_features(struct fpu_guest *guest_fpu, u64 xfeatures);



#ifdef CONFIG_X86_64

extern void fpu_update_guest_xfd(struct fpu_guest *guest_fpu, u64 xfd);

#else

static inline void fpu_update_guest_xfd(struct fpu_guest *guest_fpu, u64 xfd) { }

#endif



extern void fpu_copy_guest_fpstate_to_uabi(struct fpu_guest *gfpu, void *buf, unsigned int size, u32 pkru);

extern int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf, u64 xcr0, u32 *vpkru);

arch/x86/kernel/fpu/core.c

+12 −0
Original line number Diff line number Diff line
@@ -283,6 +283,18 @@ int fpu_enable_guest_xfd_features(struct fpu_guest *guest_fpu, u64 xfeatures) 
}

EXPORT_SYMBOL_GPL(fpu_enable_guest_xfd_features);



#ifdef CONFIG_X86_64

void fpu_update_guest_xfd(struct fpu_guest *guest_fpu, u64 xfd)

{

	fpregs_lock();

	guest_fpu->fpstate->xfd = xfd;

	if (guest_fpu->fpstate->in_use)

		xfd_update_state(guest_fpu->fpstate);

	fpregs_unlock();

}

EXPORT_SYMBOL_GPL(fpu_update_guest_xfd);

#endif /* CONFIG_X86_64 */



int fpu_swap_kvm_fpstate(struct fpu_guest *guest_fpu, bool enter_guest)

{

	struct fpstate *guest_fps = guest_fpu->fpstate;