diff options
| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2023-05-11 15:47:32 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2023-05-22 14:52:58 +0200 |
| commit | eb799279fb1f9c63c520fe8c1c41cb9154252db6 (patch) | |
| tree | b08af898ed7e318df35b97abb6650f5efdcfdaf8 /lib/debugobjects.c | |
| parent | debugobjects,locking: Annotate debug_object_fill_pool() wait type violation (diff) | |
| download | linux-eb799279fb1f9c63c520fe8c1c41cb9154252db6.tar.xz linux-eb799279fb1f9c63c520fe8c1c41cb9154252db6.zip | |
debugobjects: Don't wake up kswapd from fill_pool()
syzbot is reporting a lockdep warning in fill_pool() because the allocation
from debugobjects is using GFP_ATOMIC, which is (__GFP_HIGH | __GFP_KSWAPD_RECLAIM)
and therefore tries to wake up kswapd, which acquires kswapd_wait::lock.
Since fill_pool() might be called with arbitrary locks held, fill_pool()
should not assume that acquiring kswapd_wait::lock is safe.
Use __GFP_HIGH instead and remove __GFP_NORETRY as it is pointless for
!__GFP_DIRECT_RECLAIM allocation.
Fixes: 3ac7fe5a4aab ("infrastructure to debug (dynamic) objects")
Reported-by: syzbot <syzbot+fe0c72f0ccbb93786380@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/6577e1fa-b6ee-f2be-2414-a2b51b1c5e30@I-love.SAKURA.ne.jp
Closes: https://syzkaller.appspot.com/bug?extid=fe0c72f0ccbb93786380
Diffstat (limited to 'lib/debugobjects.c')
| -rw-r--r-- | lib/debugobjects.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/debugobjects.c b/lib/debugobjects.c index 826c617b10a7..984985c39c9b 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -126,7 +126,7 @@ static const char *obj_states[ODEBUG_STATE_MAX] = { static void fill_pool(void) { - gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN; + gfp_t gfp = __GFP_HIGH | __GFP_NOWARN; struct debug_obj *obj; unsigned long flags; |