3 files changed, 11 insertions, 9 deletions

diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index a86d37052a64..a21a4d0ecc34 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -369,14 +369,15 @@ int fpu_swap_kvm_fpstate(struct fpu_guest *guest_fpu, bool enter_guest)
 EXPORT_SYMBOL_GPL(fpu_swap_kvm_fpstate);
 
 void fpu_copy_guest_fpstate_to_uabi(struct fpu_guest *gfpu, void *buf,
-				    unsigned int size, u32 pkru)
+				    unsigned int size, u64 xfeatures, u32 pkru)
 {
 	struct fpstate *kstate = gfpu->fpstate;
 	union fpregs_state *ustate = buf;
 	struct membuf mb = { .p = buf, .left = size };
 
 	if (cpu_feature_enabled(X86_FEATURE_XSAVE)) {
-		__copy_xstate_to_uabi_buf(mb, kstate, pkru, XSTATE_COPY_XSAVE);
+		__copy_xstate_to_uabi_buf(mb, kstate, xfeatures, pkru,
+					  XSTATE_COPY_XSAVE);
 	} else {
 		memcpy(&ustate->fxsave, &kstate->regs.fxsave,
 		       sizeof(ustate->fxsave));
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index cadf68737e6b..ef6906107c54 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1049,6 +1049,7 @@ static void copy_feature(bool from_xstate, struct membuf *to, void *xstate,
  * __copy_xstate_to_uabi_buf - Copy kernel saved xstate to a UABI buffer
  * @to:		membuf descriptor
  * @fpstate:	The fpstate buffer from which to copy
+ * @xfeatures:	The mask of xfeatures to save (XSAVE mode only)
  * @pkru_val:	The PKRU value to store in the PKRU component
  * @copy_mode:	The requested copy mode
  *
@@ -1059,7 +1060,8 @@ static void copy_feature(bool from_xstate, struct membuf *to, void *xstate,
  * It supports partial copy but @to.pos always starts from zero.
  */
 void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate,
-			       u32 pkru_val, enum xstate_copy_mode copy_mode)
+			       u64 xfeatures, u32 pkru_val,
+			       enum xstate_copy_mode copy_mode)
 {
 	const unsigned int off_mxcsr = offsetof(struct fxregs_state, mxcsr);
 	struct xregs_state *xinit = &init_fpstate.regs.xsave;
@@ -1083,7 +1085,7 @@ void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate,
 		break;
 
 	case XSTATE_COPY_XSAVE:
-		header.xfeatures &= fpstate->user_xfeatures;
+		header.xfeatures &= fpstate->user_xfeatures & xfeatures;
 		break;
 	}
 
@@ -1185,6 +1187,7 @@ void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk,
 			     enum xstate_copy_mode copy_mode)
 {
 	__copy_xstate_to_uabi_buf(to, tsk->thread.fpu.fpstate,
+				  tsk->thread.fpu.fpstate->user_xfeatures,
 				  tsk->thread.pkru, copy_mode);
 }
 
@@ -1536,10 +1539,7 @@ static int fpstate_realloc(u64 xfeatures, unsigned int ksize,
 		fpregs_restore_userregs();
 
 	newfps->xfeatures = curfps->xfeatures | xfeatures;
-
-	if (!guest_fpu)
-		newfps->user_xfeatures = curfps->user_xfeatures | xfeatures;
-
+	newfps->user_xfeatures = curfps->user_xfeatures | xfeatures;
 	newfps->xfd = curfps->xfd & ~xfeatures;
 
 	/* Do the final updates within the locked region */
diff --git a/arch/x86/kernel/fpu/xstate.h b/arch/x86/kernel/fpu/xstate.h
index a4ecb04d8d64..3518fb26d06b 100644
--- a/arch/x86/kernel/fpu/xstate.h
+++ b/arch/x86/kernel/fpu/xstate.h
@@ -43,7 +43,8 @@ enum xstate_copy_mode {
 
 struct membuf;
 extern void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate,
-				      u32 pkru_val, enum xstate_copy_mode copy_mode);
+				      u64 xfeatures, u32 pkru_val,
+				      enum xstate_copy_mode copy_mode);
 extern void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk,
 				    enum xstate_copy_mode mode);
 extern int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u32 *pkru);