diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/fpu/core.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index ab19b3d8b2f7..eddeeb4ed2f5 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -201,6 +201,26 @@ void fpu_reset_from_exception_fixup(void) #if IS_ENABLED(CONFIG_KVM) static void __fpstate_reset(struct fpstate *fpstate); +static void fpu_init_guest_permissions(struct fpu_guest *gfpu) +{ + struct fpu_state_perm *fpuperm; + u64 perm; + + if (!IS_ENABLED(CONFIG_X86_64)) + return; + + spin_lock_irq(¤t->sighand->siglock); + fpuperm = ¤t->group_leader->thread.fpu.guest_perm; + perm = fpuperm->__state_perm; + + /* First fpstate allocation locks down permissions. */ + WRITE_ONCE(fpuperm->__state_perm, perm | FPU_GUEST_PERM_LOCKED); + + spin_unlock_irq(¤t->sighand->siglock); + + gfpu->perm = perm & ~FPU_GUEST_PERM_LOCKED; +} + bool fpu_alloc_guest_fpstate(struct fpu_guest *gfpu) { struct fpstate *fpstate; @@ -216,7 +236,11 @@ bool fpu_alloc_guest_fpstate(struct fpu_guest *gfpu) fpstate->is_valloc = true; fpstate->is_guest = true; - gfpu->fpstate = fpstate; + gfpu->fpstate = fpstate; + gfpu->xfeatures = fpu_user_cfg.default_features; + gfpu->perm = fpu_user_cfg.default_features; + fpu_init_guest_permissions(gfpu); + return true; } EXPORT_SYMBOL_GPL(fpu_alloc_guest_fpstate); |