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authorPaolo Bonzini <pbonzini@redhat.com>2021-07-08 20:15:57 +0300
committerPaolo Bonzini <pbonzini@redhat.com>2021-07-14 19:14:27 +0300
commitf3cf800778e9e76b2387d00c9bfbc2e16efdb7ed (patch)
tree783e27546a8d65df254f59b5a024dc42eb390582 /arch/x86/include/asm/fpu/internal.h
parentb8917b4ae44d1b945f6fba3d8ee6777edb44633b (diff)
parentcd4220d23bf3f43cf720e82bdee681f383433ae2 (diff)
downloadlinux-f3cf800778e9e76b2387d00c9bfbc2e16efdb7ed.tar.xz
Merge tag 'kvm-s390-master-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: selftests: Fixes - provide memory model for IBM z196 and zEC12 - do not require 64GB of memory
Diffstat (limited to 'arch/x86/include/asm/fpu/internal.h')
-rw-r--r--arch/x86/include/asm/fpu/internal.h20
1 files changed, 10 insertions, 10 deletions
diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index 8d33ad80704f..fdee23ea4e17 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -578,19 +578,19 @@ static inline void switch_fpu_finish(struct fpu *new_fpu)
* PKRU state is switched eagerly because it needs to be valid before we
* return to userland e.g. for a copy_to_user() operation.
*/
- if (current->mm) {
+ if (!(current->flags & PF_KTHREAD)) {
+ /*
+ * If the PKRU bit in xsave.header.xfeatures is not set,
+ * then the PKRU component was in init state, which means
+ * XRSTOR will set PKRU to 0. If the bit is not set then
+ * get_xsave_addr() will return NULL because the PKRU value
+ * in memory is not valid. This means pkru_val has to be
+ * set to 0 and not to init_pkru_value.
+ */
pk = get_xsave_addr(&new_fpu->state.xsave, XFEATURE_PKRU);
- if (pk)
- pkru_val = pk->pkru;
+ pkru_val = pk ? pk->pkru : 0;
}
__write_pkru(pkru_val);
-
- /*
- * Expensive PASID MSR write will be avoided in update_pasid() because
- * TIF_NEED_FPU_LOAD was set. And the PASID state won't be updated
- * unless it's different from mm->pasid to reduce overhead.
- */
- update_pasid();
}
#endif /* _ASM_X86_FPU_INTERNAL_H */