diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 46b935bc87c8..8d0f6019c21d 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -404,6 +404,14 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf,
 	if (ustate->xsave.header.xfeatures & ~xcr0)
 		return -EINVAL;
 
+	/*
+	 * Nullify @vpkru to preserve its current value if PKRU's bit isn't set
+	 * in the header.  KVM's odd ABI is to leave PKRU untouched in this
+	 * case (all other components are eventually re-initialized).
+	 */
+	if (!(ustate->xsave.header.xfeatures & XFEATURE_MASK_PKRU))
+		vpkru = NULL;
+
 	return copy_uabi_from_kernel_to_xstate(kstate, ustate, vpkru);
 }
 EXPORT_SYMBOL_GPL(fpu_copy_uabi_to_guest_fpstate);
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index a8cf604d8a25..714166cc25f2 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1219,8 +1219,14 @@ static int copy_from_buffer(void *dst, unsigned int offset, unsigned int size,
  *	it is harmless.
  * 2.	When called from ptrace the PKRU register will be restored from the
  *	thread_struct's pkru field. A pointer to that is passed in @pkru.
+ *	The kernel will restore it manually, so the XRSTOR behavior that resets
+ *	the PKRU register to the hardware init value (0) if the corresponding
+ *	xfeatures bit is not set is emulated here.
  * 3.	When called from KVM the PKRU register will be restored from the vcpu's
- *	pkru field. A pointer to that is passed in @pkru.
+ *	pkru field. A pointer to that is passed in @pkru. KVM hasn't used
+ *	XRSTOR and hasn't had the PKRU resetting behavior described above. To
+ *	preserve that KVM behavior, it passes NULL for @pkru if the xfeatures
+ *	bit is not set.
  */
 static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf,
 			       const void __user *ubuf, u32 *pkru)
@@ -1277,6 +1283,13 @@ static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf,
 
 		xpkru = __raw_xsave_addr(xsave, XFEATURE_PKRU);
 		*pkru = xpkru->pkru;
+	} else {
+		/*
+		 * KVM may pass NULL here to indicate that it does not need
+		 * PKRU updated.
+		 */
+		if (pkru)
+			*pkru = 0;
 	}
 
 	/*