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 17FFA28A415; Wed, 23 Apr 2025 15:33:48 +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=1745422428; cv=none; b=YnEX0LTuOMLlgwnVfMLev+xtQs3vVHKnPdsR5v17IqZRvnkre9t7gDwKolnfBxtGxVZn+snRIlG1bBmrXwO0uL1n9RBXK/0YKs7VcLZul5AA7SXAFp5bO3lGBTAfgh0J0Zj1I7E5BIPy+2kz5sq15C6oH/qHMvImWWh4dr+sTZ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745422428; c=relaxed/simple; bh=/1f0iCgRqlfcL8ka7PbIUvOnFOkFBUVVEIciuh1uC2s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ATHCxE8cbpOI6TtlXRGWYSebBSxzav2AKcQlA+zVB/KWm7Ft7b1M3jtof5kvgTLNXcQwn4unU6uUj0nx6SnaUOivyzxDMXk2Ol4Rt9VvpHZgp5IwRaffH5/uoPLcOAHznsKw/2RpsvPYLnmoGfLqxxA1HnaPeAcf4brmwTlrEl0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=pTC/HmN9; 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="pTC/HmN9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9E74EC4CEE2; Wed, 23 Apr 2025 15:33:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745422428; bh=/1f0iCgRqlfcL8ka7PbIUvOnFOkFBUVVEIciuh1uC2s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pTC/HmN9ra8DT11DWyH9tVQEv0jaTS8gy6N5Ak/heN2k1tw4Ghh/BhqaivscdUF52 C+ItkXwoChVM7m8i3ejw5Eekgcwe1iP0w3YVp3eBWGJgYoKNwnkqHfb6ke2ak0XoFX xTgvAxJua0asOB79OoDZzIsSomkR71MQsFmXoqIs= 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 6.1 284/291] blk-iocost: do not WARN if iocg was already offlined Date: Wed, 23 Apr 2025 16:44:33 +0200 Message-ID: <20250423142636.026790100@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250423142624.409452181@linuxfoundation.org> References: <20250423142624.409452181@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-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 @@ -1430,8 +1430,11 @@ 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);