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Diffstat (limited to 'arch/x86/kernel/fpu/core.c')
-rw-r--r--arch/x86/kernel/fpu/core.c21
1 files changed, 9 insertions, 12 deletions
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 3b28c5b25e12..9baa89a8877d 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -391,8 +391,6 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf,
{
struct fpstate *kstate = gfpu->fpstate;
const union fpregs_state *ustate = buf;
- struct pkru_state *xpkru;
- int ret;
if (!cpu_feature_enabled(X86_FEATURE_XSAVE)) {
if (ustate->xsave.header.xfeatures & ~XFEATURE_MASK_FPSSE)
@@ -406,16 +404,15 @@ int fpu_copy_uabi_to_guest_fpstate(struct fpu_guest *gfpu, const void *buf,
if (ustate->xsave.header.xfeatures & ~xcr0)
return -EINVAL;
- ret = copy_uabi_from_kernel_to_xstate(kstate, ustate);
- if (ret)
- return ret;
+ /*
+ * 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;
- /* Retrieve PKRU if not in init state */
- if (kstate->regs.xsave.header.xfeatures & XFEATURE_MASK_PKRU) {
- xpkru = get_xsave_addr(&kstate->regs.xsave, XFEATURE_PKRU);
- *vpkru = xpkru->pkru;
- }
- return 0;
+ return copy_uabi_from_kernel_to_xstate(kstate, ustate, vpkru);
}
EXPORT_SYMBOL_GPL(fpu_copy_uabi_to_guest_fpstate);
#endif /* CONFIG_KVM */
@@ -605,9 +602,9 @@ int fpu_clone(struct task_struct *dst, unsigned long clone_flags, bool minimal)
if (test_thread_flag(TIF_NEED_FPU_LOAD))
fpregs_restore_userregs();
save_fpregs_to_fpstate(dst_fpu);
+ fpregs_unlock();
if (!(clone_flags & CLONE_THREAD))
fpu_inherit_perms(dst_fpu);
- fpregs_unlock();
/*
* Children never inherit PASID state.