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| author | Joerg Roedel <joerg.roedel@amd.com> | 2010-06-01 09:57:49 +0200 |
|---|---|---|
| committer | Joerg Roedel <joerg.roedel@amd.com> | 2010-06-01 09:57:49 +0200 |
| commit | 1d61e73ab4c7470833241af888939a7aab2b0354 (patch) | |
| tree | dd714c2428070a7ea2bf807c2821ac75ff13ec55 /arch/x86/kernel/kprobes.c | |
| parent | 84fe6c19e4a598e8071e3bd1b2c923454eae1268 (diff) | |
| parent | 67a3e12b05e055c0415c556a315a3d3eb637e29e (diff) | |
Merge commit 'v2.6.35-rc1' into amd-iommu/2.6.35
Diffstat (limited to 'arch/x86/kernel/kprobes.c')
| -rw-r--r-- | arch/x86/kernel/kprobes.c | 43 |
1 files changed, 25 insertions, 18 deletions
diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c index b43bbaebe2c0..345a4b1fe144 100644 --- a/arch/x86/kernel/kprobes.c +++ b/arch/x86/kernel/kprobes.c @@ -422,14 +422,22 @@ static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs, static void __kprobes clear_btf(void) { - if (test_thread_flag(TIF_DEBUGCTLMSR)) - update_debugctlmsr(0); + if (test_thread_flag(TIF_BLOCKSTEP)) { + unsigned long debugctl = get_debugctlmsr(); + + debugctl &= ~DEBUGCTLMSR_BTF; + update_debugctlmsr(debugctl); + } } static void __kprobes restore_btf(void) { - if (test_thread_flag(TIF_DEBUGCTLMSR)) - update_debugctlmsr(current->thread.debugctlmsr); + if (test_thread_flag(TIF_BLOCKSTEP)) { + unsigned long debugctl = get_debugctlmsr(); + + debugctl |= DEBUGCTLMSR_BTF; + update_debugctlmsr(debugctl); + } } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, @@ -534,20 +542,6 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) struct kprobe_ctlblk *kcb; addr = (kprobe_opcode_t *)(regs->ip - sizeof(kprobe_opcode_t)); - if (*addr != BREAKPOINT_INSTRUCTION) { - /* - * The breakpoint instruction was removed right - * after we hit it. Another cpu has removed - * either a probepoint or a debugger breakpoint - * at this address. In either case, no further - * handling of this interrupt is appropriate. - * Back up over the (now missing) int3 and run - * the original instruction. - */ - regs->ip = (unsigned long)addr; - return 1; - } - /* * We don't want to be preempted for the entire * duration of kprobe processing. We conditionally @@ -579,6 +573,19 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) setup_singlestep(p, regs, kcb, 0); return 1; } + } else if (*addr != BREAKPOINT_INSTRUCTION) { + /* + * The breakpoint instruction was removed right + * after we hit it. Another cpu has removed + * either a probepoint or a debugger breakpoint + * at this address. In either case, no further + * handling of this interrupt is appropriate. + * Back up over the (now missing) int3 and run + * the original instruction. + */ + regs->ip = (unsigned long)addr; + preempt_enable_no_resched(); + return 1; } else if (kprobe_running()) { p = __get_cpu_var(current_kprobe); if (p->break_handler && p->break_handler(p, regs)) { |