From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) (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 85C7F383C64 for ; Thu, 16 Apr 2026 11:55:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=18.9.28.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776340545; cv=none; b=BCE14wc04B2J4YuzC1qfIv/UR/hokwyWsy6+3awP/WK3SAMAAr9jO+xmTH1w0puwZvD+w2udk2cs5bgjha9TYdpxe5MxlW6gjqcvFv4Ga7u4q3dz17t/yZcvAV/4EYzVMLJmpLkTf+urPQc5SVxmOCbMKKMk4HMDne60sByMcGE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776340545; c=relaxed/simple; bh=JnAje/X9C8YfhGOCIz1/VlVMqdAl8bBSAceIJfqsCBU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=nO8LLiBhN9XGvWpwUysWyFf/WyhvckpEc5R4pHLTs44tYdNiLPbvLwsRtKwdVCzfzs27BYrbFxHjlRYlsTUn6WhhMSFgSvNfK2dXCA7yxWLkn4bKimqWBdV/fBkqFWNThSirRvgru5JsVeVsK548mdmhn5x6um99qqlrh1p3u+4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu; spf=pass smtp.mailfrom=mit.edu; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b=Hr+sVbO7; arc=none smtp.client-ip=18.9.28.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mit.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b="Hr+sVbO7" Received: from macsyma.thunk.org (pool-173-48-114-3.bstnma.fios.verizon.net [173.48.114.3]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 63GBtZCQ002971 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 16 Apr 2026 07:55:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mit.edu; s=outgoing; t=1776340537; bh=9jMqHZPxzURZPW1OByiLgBIV+rz7GoO0YmLISCkb15I=; h=Date:From:Subject:Message-ID:MIME-Version:Content-Type; b=Hr+sVbO7ieFg8cNLwX4SD7vcElY552KLGd5QfwmsL0BdGCgHFEV1Vlx90BmlZbcn6 Jo4UMK3pbplvQntGfyVVXodErtriYLb+AG3MKK8thCHW/icvbC9Vy91eOnFaSGYfXb XICo4JLNJKj/2Vn4HSOaDbsSdMVU1E6ppguxpsLqqHFz1lZtADexWTDzhbej6kYAb5 LlNz1N7GXhjalVHHT0XkfG6xeI6mO2u6g/QATmw3A00XW+ukbctbBKWG0MNEQfxe9A sKEd2ZuZVIYEz8VGKdqXT4i/ehflhhRVauZ+KMDpJAkjuCYZGXBMr1H6PZOhtWIC48 Jkuh0huoYLFQQ== Received: by macsyma.thunk.org (Postfix, from userid 15806) id 582396375041; Thu, 16 Apr 2026 07:54:35 -0400 (EDT) Date: Thu, 16 Apr 2026 07:54:35 -0400 From: "Theodore Tso" To: Jan Kara Cc: Andreas Dilger , Milos Nikic , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] jbd2: enforce power-of-two default revoke hash size at compile time Message-ID: <20260416115435.GA52577@macsyma-wired.lan> References: <20260413212724.127035-1-nikic.milos@gmail.com> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Apr 16, 2026 at 12:16:05PM +0200, Jan Kara wrote: > > Yes, I know. But there is already a runtime assertion in > jbd2_journal_init_revoke() making sure the passed value is a power of two > which is verifying also other callers that aren't using > JOURNAL_REVOKE_DEFAULT_HASH value. I don't see a value in the *additional* > BUILD_BUG_ON when we already have that runtime check. ... and if a developer doesn't run regression tests before bothering the list with a patch... that's not a developer we want to cater to. Milos, my recommended to workflow is to use kvm-xfstests[1], and just do: % install-kconfig % kbuild % kvm-xfstests smoke [1] https://github.com/tytso/xfstests-bld/blob/master/Documentation/kvm-quickstart.md For a successful run, "kvm-xfstests smoke" will run take 15-20 minutes. In the case of screwing up the default power-of-two default revoke hash size, "kvm-xfstests smoke" will report a failure in less than a minute. - Ted