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| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2012-08-07 18:12:28 +0200 |
|---|---|---|
| committer | Oleg Nesterov <oleg@redhat.com> | 2012-09-15 17:37:28 +0200 |
| commit | 9d778782266f95e5c6ec43ed8195ba331c821018 (patch) | |
| tree | 99872945803a76d1ff9e438cf48864cd0a5d9bf4 | |
| parent | 499a4f3ec057a0f79636cc3c1e581bb6e977a30f (diff) | |
| download | linux-9d778782266f95e5c6ec43ed8195ba331c821018.tar.gz linux-9d778782266f95e5c6ec43ed8195ba331c821018.tar.bz2 linux-9d778782266f95e5c6ec43ed8195ba331c821018.zip | |
uprobes: Introduce arch_uprobe_enable/disable_step()
As Oleg pointed out in [0] uprobe should not use the ptrace interface
for enabling/disabling single stepping.
[0] http://lkml.kernel.org/r/20120730141638.GA5306@redhat.com
Add the new "__weak arch" helpers which simply call user_*_single_step()
as a preparation. This is only needed to not break the powerpc port, we
will fold this logic into arch_uprobe_pre/post_xol() hooks later.
We should also change handle_singlestep(), _disable_step(&uprobe->arch)
should be called before put_uprobe().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
| -rw-r--r-- | include/linux/uprobes.h | 2 | ||||
| -rw-r--r-- | kernel/events/uprobes.c | 14 |
2 files changed, 14 insertions, 2 deletions
diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 6d4fe79a1a6a..e6f0331e3d45 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -112,6 +112,8 @@ extern void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm); extern void uprobe_free_utask(struct task_struct *t); extern void uprobe_copy_process(struct task_struct *t); extern unsigned long __weak uprobe_get_swbp_addr(struct pt_regs *regs); +extern void __weak arch_uprobe_enable_step(struct arch_uprobe *arch); +extern void __weak arch_uprobe_disable_step(struct arch_uprobe *arch); extern int uprobe_post_sstep_notifier(struct pt_regs *regs); extern int uprobe_pre_sstep_notifier(struct pt_regs *regs); extern void uprobe_notify_resume(struct pt_regs *regs); diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index e4a906ce2e1d..912ef48d28ab 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1444,6 +1444,16 @@ static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp) return uprobe; } +void __weak arch_uprobe_enable_step(struct arch_uprobe *arch) +{ + user_enable_single_step(current); +} + +void __weak arch_uprobe_disable_step(struct arch_uprobe *arch) +{ + user_disable_single_step(current); +} + /* * Run handler and ask thread to singlestep. * Ensure all non-fatal signals cannot interrupt thread while it singlesteps. @@ -1490,7 +1500,7 @@ static void handle_swbp(struct pt_regs *regs) utask->state = UTASK_SSTEP; if (!pre_ssout(uprobe, regs, bp_vaddr)) { - user_enable_single_step(current); + arch_uprobe_enable_step(&uprobe->arch); return; } @@ -1526,10 +1536,10 @@ static void handle_singlestep(struct uprobe_task *utask, struct pt_regs *regs) else WARN_ON_ONCE(1); + arch_uprobe_disable_step(&uprobe->arch); put_uprobe(uprobe); utask->active_uprobe = NULL; utask->state = UTASK_RUNNING; - user_disable_single_step(current); xol_free_insn_slot(current); spin_lock_irq(¤t->sighand->siglock); |