From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A288B243364; Tue, 29 Apr 2025 17:52:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745949163; cv=none; b=aFlctSa3Kna2YWNKvVzdqPvXmqEW9T/ur5+MQ6BU+9mS2ZFIY409Iso/h+ts1zQrA5mtUEoyudHXp5HeS9/Tymq0XYnvZyXdMmT71ubarQ21OuovZwM4wp/PcnugcDlDRtZP7fZuSSypJvb/4nT99Fpi42pZQg0yViISyDI8qe8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745949163; c=relaxed/simple; bh=n1fhY8JzQa3ctzA2kLS9RpAziYHPTZjR2EbYdGxhn7Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sdQCy/JynJIxXXL24qlTg4sve7Ew75ZmSh70glsFXRlJioaT9aJPjCx1ZxfzQcvPCcaf33wlUQNiVM17jTF3CZ66k3MsJV+B+b7Ift8HYiqPzCoNB10ROn6P9ZtITqqw6kNPYz1Tf9DkxIsXfOMHBm//ovxO21iKU4bqxpXEbBA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=znqHnbFB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="znqHnbFB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4917C4CEE3; Tue, 29 Apr 2025 17:52:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745949163; bh=n1fhY8JzQa3ctzA2kLS9RpAziYHPTZjR2EbYdGxhn7Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=znqHnbFBrmnUZkeSObiV/2bdV6ZLY+Zeya5guoPfgdl4bjAtMDI85DGi6kS0xCBe2 nljtUYh2UL2EAwvfdyYFVmPYxf7kBOTAuY8m1XKQChDcPdXInLLhsX3tI6a2Ttxx+B GnMJt0BkrKkhalMowldXZjVcJt8FigaKFSLl8Rdw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Nan , Yu Kuai , Tejun Heo , Jens Axboe , Bin Lan , He Zhe Subject: [PATCH 5.15 233/373] blk-iocost: do not WARN if iocg was already offlined Date: Tue, 29 Apr 2025 18:41:50 +0200 Message-ID: <20250429161132.725979501@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161123.119104857@linuxfoundation.org> References: <20250429161123.119104857@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Li Nan commit 01bc4fda9ea0a6b52f12326486f07a4910666cf6 upstream. In iocg_pay_debt(), warn is triggered if 'active_list' is empty, which is intended to confirm iocg is active when it has debt. However, warn can be triggered during a blkcg or disk removal, if iocg_waitq_timer_fn() is run at that time: WARNING: CPU: 0 PID: 2344971 at block/blk-iocost.c:1402 iocg_pay_debt+0x14c/0x190 Call trace: iocg_pay_debt+0x14c/0x190 iocg_kick_waitq+0x438/0x4c0 iocg_waitq_timer_fn+0xd8/0x130 __run_hrtimer+0x144/0x45c __hrtimer_run_queues+0x16c/0x244 hrtimer_interrupt+0x2cc/0x7b0 The warn in this situation is meaningless. Since this iocg is being removed, the state of the 'active_list' is irrelevant, and 'waitq_timer' is canceled after removing 'active_list' in ioc_pd_free(), which ensures iocg is freed after iocg_waitq_timer_fn() returns. Therefore, add the check if iocg was already offlined to avoid warn when removing a blkcg or disk. Signed-off-by: Li Nan Reviewed-by: Yu Kuai Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20240419093257.3004211-1-linan666@huaweicloud.com Signed-off-by: Jens Axboe Signed-off-by: Bin Lan Signed-off-by: He Zhe Signed-off-by: Greg Kroah-Hartman --- block/blk-iocost.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -1435,8 +1435,11 @@ static void iocg_pay_debt(struct ioc_gq lockdep_assert_held(&iocg->ioc->lock); lockdep_assert_held(&iocg->waitq.lock); - /* make sure that nobody messed with @iocg */ - WARN_ON_ONCE(list_empty(&iocg->active_list)); + /* + * make sure that nobody messed with @iocg. Check iocg->pd.online + * to avoid warn when removing blkcg or disk. + */ + WARN_ON_ONCE(list_empty(&iocg->active_list) && iocg->pd.online); WARN_ON_ONCE(iocg->inuse > 1); iocg->abs_vdebt -= min(abs_vpay, iocg->abs_vdebt);