Revert "x86/mm: Only set IBPB when the new thread cannot ptrace current thread"

[mirror_ubuntu-artful-kernel.git] / arch / x86 / mm / tlb.c

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 301e6efbc5141dc903812b60a72887ca5e16a5ca..bb3ded3a4e5f4553a1d47c930a98de8562bc0270 100644 (file)
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -6,7 +6,6 @@
 #include <linux/interrupt.h>
 #include <linux/export.h>
 #include <linux/cpu.h>
-#include <linux/ptrace.h>
 
 #include <asm/tlbflush.h>
 #include <asm/mmu_context.h>
@@ -220,9 +219,7 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
                u16 new_asid;
                bool need_flush;
 
-               /* Null tsk means switching to kernel, so that's safe */
-               if (boot_cpu_has(X86_FEATURE_SPEC_CTRL) && tsk &&
-                       ___ptrace_may_access(tsk, current, PTRACE_MODE_IBPB))
+               if (boot_cpu_has(X86_FEATURE_SPEC_CTRL))
                        native_wrmsrl(MSR_IA32_PRED_CMD, FEATURE_SET_IBPB);
 
                if (IS_ENABLED(CONFIG_VMAP_STACK)) {