Following up on my previous key reference accounting patches, this patch
will catch puts on keys that haven't been "got". This won't catch nested
get/put mismatches though.
Build and boot tested, with minimal desktop activity and a run of the
open_posix_testsuite in LTP for testing. No warnings logged.
Signed-off-by: Darren Hart <[email protected]>
Cc: "Peter Zijlstra" <[email protected]>
Cc: "Thomas Gleixner" <[email protected]>
Cc: "Rusty Russell" <[email protected]>
---
kernel/futex.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/kernel/futex.c b/kernel/futex.c
index 748778a..5288acf 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -170,8 +170,11 @@ static void get_futex_key_refs(union futex_key *key)
*/
static void drop_futex_key_refs(union futex_key *key)
{
- if (!key->both.ptr)
+ if (!key->both.ptr) {
+ /* If we're here then we tried to put a key we failed to get */
+ WARN_ON(1);
return;
+ }
switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
case FUT_OFF_INODE:
* Darren Hart <[email protected]> wrote:
> Following up on my previous key reference accounting patches, this patch
> will catch puts on keys that haven't been "got". This won't catch nested
> get/put mismatches though.
>
> Build and boot tested, with minimal desktop activity and a run of the
> open_posix_testsuite in LTP for testing. No warnings logged.
>
> Signed-off-by: Darren Hart <[email protected]>
> Cc: "Peter Zijlstra" <[email protected]>
> Cc: "Thomas Gleixner" <[email protected]>
> Cc: "Rusty Russell" <[email protected]>
> ---
>
> kernel/futex.c | 5 ++++-
> 1 files changed, 4 insertions(+), 1 deletions(-)
applied to tip/core/futexes, thanks!
I changed this:
> + WARN_ON(1);
> return;
to WARN_ON_ONCE() - warning once per bootup is good enough for
kerneloops.org to pick it up, while a ton of warnings add no extra (other
than to inconvenience the user, or even make the system unworkable).
Ingo