[lkml]   [2013]   [Dec]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH 16/17] uprobes: Allocate ->utask before handler_chain() for tracing handlers
From: Oleg Nesterov <>

uprobe_trace_print() and uprobe_perf_print() need to pass the additional
info to call_fetch() methods, currently there is no simple way to do this.

current->utask looks like a natural place to hold this info, but we need
to allocate it before handler_chain().

This is a bit unfortunate, perhaps we will find a better solution later,
but this is simple and should work right now.

Signed-off-by: Oleg Nesterov <>
Acked-by: Masami Hiramatsu <>
Cc: Srikar Dronamraju <>
Signed-off-by: Namhyung Kim <>
kernel/events/uprobes.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 24b7d6ca871b..3cc8e0bb8acf 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1828,6 +1828,10 @@ static void handle_swbp(struct pt_regs *regs)
if (unlikely(!test_bit(UPROBE_COPY_INSN, &uprobe->flags)))
goto out;

+ /* Tracing handlers use ->utask to communicate with fetch methods */
+ if (!get_utask())
+ goto out;
handler_chain(uprobe, regs);
if (can_skip_sstep(uprobe, regs))
goto out;

 \ /
  Last update: 2013-12-16 06:41    [W:0.266 / U:0.248 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site