diff options
| author | Vikram Mulukutla <markivx@codeaurora.org> | 2014-12-17 18:50:56 -0800 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2015-03-01 23:34:17 +0100 |
| commit | d016c1bd3d9f062b27e6f36c5c339f88e25a4712 (patch) | |
| tree | 62cd6d6865f3e18527a6e6ebe9c98315a78ebcb2 /kernel | |
| parent | 28d388537dd995cb375177495d1bcd1512415b04 (diff) | |
tracing: Fix unmapping loop in tracing_mark_write
commit 7215853e985a4bef1a6c14e00e89dfec84f1e457 upstream.
Commit 6edb2a8a385f0cdef51dae37ff23e74d76d8a6ce introduced
an array map_pages that contains the addresses returned by
kmap_atomic. However, when unmapping those pages, map_pages[0]
is unmapped before map_pages[1], breaking the nesting requirement
as specified in the documentation for kmap_atomic/kunmap_atomic.
This was caught by the highmem debug code present in kunmap_atomic.
Fix the loop to do the unmapping properly.
Link: http://lkml.kernel.org/r/1418871056-6614-1-git-send-email-markivx@codeaurora.org
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Reported-by: Lime Yang <limey@codeaurora.org>
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 691a8ea6f472..1b51436db225 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4599,7 +4599,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, *fpos += written; out_unlock: - for (i = 0; i < nr_pages; i++){ + for (i = nr_pages - 1; i >= 0; i--) { kunmap_atomic(map_page[i]); put_page(pages[i]); } |