[PATCH 2/5] uprobes: Do not setup ->active_uprobe/state prematurely

From: Oleg Nesterov
Date: Fri Sep 14 2012 - 13:14:06 EST


handle_swbp() sets utask->active_uprobe before handler_chain(),
and UTASK_SSTEP before pre_ssout(). This complicates the code
for no reason, arch_ hooks or consumer->handler() should not
(and can't) use this info.

Change handle_swbp() to initialize them after pre_ssout(), and
remove the no longer needed cleanup-utask code.

Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
---
kernel/events/uprobes.c | 9 +++------
1 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 760acc1..9893cba 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1496,22 +1496,19 @@ static void handle_swbp(struct pt_regs *regs)
if (!utask)
goto cleanup_ret;
}
- utask->active_uprobe = uprobe;
+
handler_chain(uprobe, regs);
if (uprobe->flags & UPROBE_SKIP_SSTEP && can_skip_sstep(uprobe, regs))
goto cleanup_ret;

- utask->state = UTASK_SSTEP;
if (!pre_ssout(uprobe, regs, bp_vaddr)) {
arch_uprobe_enable_step(&uprobe->arch);
+ utask->active_uprobe = uprobe;
+ utask->state = UTASK_SSTEP;
return;
}

cleanup_ret:
- if (utask) {
- utask->active_uprobe = NULL;
- utask->state = UTASK_RUNNING;
- }
if (!(uprobe->flags & UPROBE_SKIP_SSTEP))

/*
--
1.5.5.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/