From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48D9CC04ABB for ; Tue, 11 Sep 2018 16:57:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E5A7A20839 for ; Tue, 11 Sep 2018 16:57:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E5A7A20839 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727966AbeIKV6B (ORCPT ); Tue, 11 Sep 2018 17:58:01 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:52688 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726989AbeIKV6A (ORCPT ); Tue, 11 Sep 2018 17:58:00 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9C63240216EB; Tue, 11 Sep 2018 16:57:48 +0000 (UTC) Received: from segfault.boston.devel.redhat.com (segfault.boston.devel.redhat.com [10.19.60.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6E822ED144; Tue, 11 Sep 2018 16:57:48 +0000 (UTC) From: Jeff Moyer To: Jens Axboe Cc: Takashi Iwai , Paolo Valente , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [REGRESSION] bfq probe failed on 4.19-rc3 References: <8b5a7dc9-2dc1-16ee-4b05-a72eb6680c77@kernel.dk> <8d5f3ab2-50e8-226c-8ccb-c722872910db@kernel.dk> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Tue, 11 Sep 2018 12:57:48 -0400 In-Reply-To: <8d5f3ab2-50e8-226c-8ccb-c722872910db@kernel.dk> (Jens Axboe's message of "Tue, 11 Sep 2018 10:54:19 -0600") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 11 Sep 2018 16:57:48 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 11 Sep 2018 16:57:48 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jmoyer@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jens Axboe writes: >> And then there were 4... > > Exactly. I'd bump it to 5 to leave room for one more, if we have to grow it > again, probably worth it to make it dynamic. So for, not really needed. Takashi, > can verify that the below fixes it up for you? > You can slap a Reviewed-by: Jeff Moyer on that when you commit it. Cheers, Jeff > > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index c19f9078da1e..c630e02836a8 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -1510,8 +1510,10 @@ int blkcg_policy_register(struct blkcg_policy *pol) > for (i = 0; i < BLKCG_MAX_POLS; i++) > if (!blkcg_policy[i]) > break; > - if (i >= BLKCG_MAX_POLS) > + if (i >= BLKCG_MAX_POLS) { > + pr_warn("blkcg_policy_register: BLKCG_MAX_POLS too small\n"); > goto err_unlock; > + } > > /* Make sure cpd/pd_alloc_fn and cpd/pd_free_fn in pairs */ > if ((!pol->cpd_alloc_fn ^ !pol->cpd_free_fn) || > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index d6869e0e2b64..6980014357d4 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -54,7 +54,7 @@ struct blk_stat_callback; > * Maximum number of blkcg policies allowed to be registered concurrently. > * Defined here to simplify include dependency. > */ > -#define BLKCG_MAX_POLS 3 > +#define BLKCG_MAX_POLS 5 > > typedef void (rq_end_io_fn)(struct request *, blk_status_t);