diff options
Diffstat (limited to 'arch/x86/include/asm/fpu/internal.h')
| -rw-r--r-- | arch/x86/include/asm/fpu/internal.h | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index 3e0c2c496f2d..6eb4a0b1ad0e 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -14,6 +14,7 @@ #include <linux/compat.h> #include <linux/sched.h> #include <linux/slab.h> +#include <linux/mm.h> #include <asm/user.h> #include <asm/fpu/api.h> @@ -534,8 +535,27 @@ switch_fpu_prepare(struct fpu *old_fpu, int cpu) */ static inline void switch_fpu_finish(struct fpu *new_fpu, int cpu) { - if (static_cpu_has(X86_FEATURE_FPU)) - __fpregs_load_activate(new_fpu, cpu); + u32 pkru_val = init_pkru_value; + struct pkru_state *pk; + + if (!static_cpu_has(X86_FEATURE_FPU)) + return; + + __fpregs_load_activate(new_fpu, cpu); + + if (!cpu_feature_enabled(X86_FEATURE_OSPKE)) + return; + + /* + * 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) { + pk = get_xsave_addr(&new_fpu->state.xsave, XFEATURE_PKRU); + if (pk) + pkru_val = pk->pkru; + } + __write_pkru(pkru_val); } /* |