From nobody Sun Feb 8 09:22:24 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5AB8C7EE26 for ; Mon, 22 May 2023 12:56:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233884AbjEVM4R (ORCPT ); Mon, 22 May 2023 08:56:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233823AbjEVM4N (ORCPT ); Mon, 22 May 2023 08:56:13 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35DA7AA; Mon, 22 May 2023 05:56:12 -0700 (PDT) Date: Mon, 22 May 2023 12:56:08 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1684760169; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yIrOEV3UUxlpbFp+rN0C9KkFZE50OIvh19Gvh/h9PPI=; b=AXMVhD7wnq7tAsoCB2MKnK97xN50ZcD8klFg6Wj6qviHET2vAtpn7OVFM2bxOti1SpneFS yGvLgyptQCLNgTbpAqZlGz+oKd0eLKKIeX9qqXSySAyqCzkdkwaU6fv6dKzHgKj3J65a27 2oZJENG60anNOsK0iZRleQydZIgYSxfjxpKGRksOymdv2QwAXauxJyF/NvaAIAIVemFrTG pwITXqR9HwHHojkqxDIURt7Fp80+9Nicg+dspJzvK2JFwSX/RMKyh1/PFhoM6UHoq0xYCo EYhg/ykdhEmSfnUy/iCS/JhSCtclJWVW9s36vIPTamPbxVH2qQjhKIp5KgacpA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1684760169; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yIrOEV3UUxlpbFp+rN0C9KkFZE50OIvh19Gvh/h9PPI=; b=xOxkYSSlje/0EhkPNJm+Fc2y2qqVefNJ2o/aaP/Av0WCGIh0wH22GE53Zg4QwKacNneK1s AKTJKYMOtX5R+RCQ== From: "tip-bot2 for Tetsuo Handa" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: core/debugobjects] debugobjects: Don't wake up kswapd from fill_pool() Cc: syzbot , Tetsuo Handa , Thomas Gleixner , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <6577e1fa-b6ee-f2be-2414-a2b51b1c5e30@I-love.SAKURA.ne.jp> References: <6577e1fa-b6ee-f2be-2414-a2b51b1c5e30@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Message-ID: <168476016890.404.6911447269153588182.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the core/debugobjects branch of t= ip: Commit-ID: eb799279fb1f9c63c520fe8c1c41cb9154252db6 Gitweb: https://git.kernel.org/tip/eb799279fb1f9c63c520fe8c1c41cb915= 4252db6 Author: Tetsuo Handa AuthorDate: Thu, 11 May 2023 22:47:32 +09:00 Committer: Thomas Gleixner CommitterDate: Mon, 22 May 2023 14:52:58 +02:00 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 Signed-off-by: Tetsuo Handa Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/6577e1fa-b6ee-f2be-2414-a2b51b1c5e30@I-love= .SAKURA.ne.jp Closes: https://syzkaller.appspot.com/bug?extid=3Dfe0c72f0ccbb93786380 --- lib/debugobjects.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/debugobjects.c b/lib/debugobjects.c index 826c617..984985c 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -126,7 +126,7 @@ static const char *obj_states[ODEBUG_STATE_MAX] =3D { =20 static void fill_pool(void) { - gfp_t gfp =3D GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN; + gfp_t gfp =3D __GFP_HIGH | __GFP_NOWARN; struct debug_obj *obj; unsigned long flags;