debugobjects: Don't wake up kswapd from fill_pool()
stable inclusion from stable-v5.10.181 commit fd673079749bac97bb30f1461df079e6c8e86511 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8GJZJ Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fd673079749bac97bb30f1461df079e6c8e86511 -------------------------------- commit eb799279 upstream. 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: 3ac7fe5a ("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 Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
sanglipeng <sanglipeng1@jd.com>
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