Commit c60427dd authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Paolo Bonzini
Browse files

x86/fpu: Add uabi_size to guest_fpu 



Userspace needs to inquire KVM about the buffer size to work
with the new KVM_SET_XSAVE and KVM_GET_XSAVE2. Add the size info
to guest_fpu for KVM to access.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarWei Wang <wei.w.wang@intel.com>
Signed-off-by: default avatarJing Liu <jing2.liu@intel.com>
Signed-off-by: default avatarYang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-18-yang.zhong@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 690a757d

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

+5 −0
Original line number Diff line number Diff line
@@ -522,6 +522,11 @@ struct fpu_guest { 
	 */

	u64				xfd_err;



	/*

	 * @uabi_size:			Size required for save/restore

	 */

	unsigned int			uabi_size;



	/*

	 * @fpstate:			Pointer to the allocated guest fpstate

	 */

arch/x86/kernel/fpu/core.c

+1 −0
Original line number Diff line number Diff line
@@ -240,6 +240,7 @@ bool fpu_alloc_guest_fpstate(struct fpu_guest *gfpu) 
	gfpu->fpstate		= fpstate;

	gfpu->xfeatures		= fpu_user_cfg.default_features;

	gfpu->perm		= fpu_user_cfg.default_features;

	gfpu->uabi_size		= fpu_user_cfg.default_size;

	fpu_init_guest_permissions(gfpu);



	return true;

arch/x86/kernel/fpu/xstate.c

+1 −0
Original line number Diff line number Diff line
@@ -1545,6 +1545,7 @@ static int fpstate_realloc(u64 xfeatures, unsigned int ksize, 
		newfps->is_confidential = curfps->is_confidential;

		newfps->in_use = curfps->in_use;

		guest_fpu->xfeatures |= xfeatures;

		guest_fpu->uabi_size = usize;

	}



	fpregs_lock();