summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorOleg Nesterov <oleg@redhat.com>2012-09-08 18:38:15 +0200
committerOleg Nesterov <oleg@redhat.com>2012-09-15 17:37:32 +0200
commitd6a00b35e411519d774d978cdf80e4406d01b36b (patch)
treee928315e06a4b6199d173848fac7d08301b32362
parent3a4664aa8362d9fa9110828f55afa9f9fcd7e484 (diff)
downloadop-kernel-dev-d6a00b35e411519d774d978cdf80e4406d01b36b.zip
op-kernel-dev-d6a00b35e411519d774d978cdf80e4406d01b36b.tar.gz
uprobes/x86: Fix arch_uprobe_disable_step() && UTASK_SSTEP_TRAPPED interaction
arch_uprobe_disable_step() should also take UTASK_SSTEP_TRAPPED into account. In this case the probed insn was not executed, we need to clear X86_EFLAGS_TF if it was set by us and that is all. Again, this code will look more clean when we move it into arch_uprobe_post_xol() and arch_uprobe_abort_xol(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
-rw-r--r--arch/x86/kernel/uprobes.c14
1 files changed, 10 insertions, 4 deletions
diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index 7e993d1f..9538f00 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -706,14 +706,20 @@ void arch_uprobe_disable_step(struct arch_uprobe *auprobe)
{
struct task_struct *task = current;
struct arch_uprobe_task *autask = &task->utask->autask;
+ bool trapped = (task->utask->state == UTASK_SSTEP_TRAPPED);
struct pt_regs *regs = task_pt_regs(task);
/*
* The state of TIF_BLOCKSTEP was not saved so we can get an extra
* SIGTRAP if we do not clear TF. We need to examine the opcode to
* make it right.
*/
- if (autask->saved_tf)
- send_sig(SIGTRAP, task, 0);
- else if (!(auprobe->fixups & UPROBE_FIX_SETF))
- regs->flags &= ~X86_EFLAGS_TF;
+ if (unlikely(trapped)) {
+ if (!autask->saved_tf)
+ regs->flags &= ~X86_EFLAGS_TF;
+ } else {
+ if (autask->saved_tf)
+ send_sig(SIGTRAP, task, 0);
+ else if (!(auprobe->fixups & UPROBE_FIX_SETF))
+ regs->flags &= ~X86_EFLAGS_TF;
+ }
}
OpenPOWER on IntegriCloud