diff options
Diffstat (limited to 'arch/x86/kernel/kprobes_32.c')
-rw-r--r-- | arch/x86/kernel/kprobes_32.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/x86/kernel/kprobes_32.c b/arch/x86/kernel/kprobes_32.c index 3a020f79f82b..bc4a68367cd0 100644 --- a/arch/x86/kernel/kprobes_32.c +++ b/arch/x86/kernel/kprobes_32.c | |||
@@ -217,8 +217,21 @@ static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs, | |||
217 | kcb->kprobe_saved_eflags &= ~IF_MASK; | 217 | kcb->kprobe_saved_eflags &= ~IF_MASK; |
218 | } | 218 | } |
219 | 219 | ||
220 | static __always_inline void clear_btf(void) | ||
221 | { | ||
222 | if (test_thread_flag(TIF_DEBUGCTLMSR)) | ||
223 | wrmsr(MSR_IA32_DEBUGCTLMSR, 0, 0); | ||
224 | } | ||
225 | |||
226 | static __always_inline void restore_btf(void) | ||
227 | { | ||
228 | if (test_thread_flag(TIF_DEBUGCTLMSR)) | ||
229 | wrmsr(MSR_IA32_DEBUGCTLMSR, current->thread.debugctlmsr, 0); | ||
230 | } | ||
231 | |||
220 | static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs) | 232 | static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs) |
221 | { | 233 | { |
234 | clear_btf(); | ||
222 | regs->eflags |= TF_MASK; | 235 | regs->eflags |= TF_MASK; |
223 | regs->eflags &= ~IF_MASK; | 236 | regs->eflags &= ~IF_MASK; |
224 | /*single step inline if the instruction is an int3*/ | 237 | /*single step inline if the instruction is an int3*/ |
@@ -542,6 +555,8 @@ static void __kprobes resume_execution(struct kprobe *p, | |||
542 | regs->eip = orig_eip + (regs->eip - copy_eip); | 555 | regs->eip = orig_eip + (regs->eip - copy_eip); |
543 | 556 | ||
544 | no_change: | 557 | no_change: |
558 | restore_btf(); | ||
559 | |||
545 | return; | 560 | return; |
546 | } | 561 | } |
547 | 562 | ||