From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (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 7862F1FDA61 for ; Thu, 11 Dec 2025 05:04:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765429463; cv=none; b=DVnt4fzQor75+P9Y+O8Q7gTMyLNr96qn6eQMHkpw1lC04SM5aZGNbuHsOdPXU4VQSiUGon/Z2i579rLP1M1rfnLvgjgci1BrDVSE71IeGJ0dEWrOz60It6DU/FOR6DmNKDjQRxtzZut4umTMdm1GvTe5dWHAoFq5ZJgxuCYgUfo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765429463; c=relaxed/simple; bh=cfrfDZE2szvkfuDH7and7mfh4tJoHtHg85C065qtess=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=dV2hJUu18k9bsm5l+yrkiJ7OccMUQVN5gmYF3x2vvmkhMok4/rTIiCXV7kTQnvFeYEtuimCGclfPe7yVN1ih5o9X15N99GZo8kl+8uf6VF3DbnNF6COOEMX9EzgaBOXbOgu+a4pos//rOexccuDhaOOML4xRQOeIUQMcptWQkV4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id DD66C227A87; Thu, 11 Dec 2025 06:04:17 +0100 (CET) Date: Thu, 11 Dec 2025 06:04:17 +0100 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Christoph Hellwig , cem@kernel.org, linux-xfs@vger.kernel.org Subject: Re: [PATCH] xfs: validate that zoned RT devices are zone aligned Message-ID: <20251211050417.GA26597@lst.de> References: <20251210142305.3660710-1-hch@lst.de> <20251210164859.GB7725@frogsfrogsfrogs> <20251210165438.GA9489@lst.de> <20251210191825.GD7725@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-xfs@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: <20251210191825.GD7725@frogsfrogsfrogs> User-Agent: Mutt/1.5.17 (2007-11-01) On Wed, Dec 10, 2025 at 11:18:25AM -0800, Darrick J. Wong wrote: > How nasty is it, exactly? AFAICT, > > * The zone targetting code (aka the zone we copy into) then has to > know to avoid a runt endzone? Yes. And I don't really have a good idea how to do that. > * Thresholding gets weird because they don't apply right to the runt > zone, which means the victim selection is also off. Yes. > * The code that reserves zones for gc or other ENOSPC handling then has > to ensure it never picks a runt zone to avoid corner case problems This is what is needed for 1) above with all the same issues. > Any other reasons? Given that zoned is still experimental I think I'm > ok with adding this restriction, but only after some more thorough > understanding. :) Yeah. > Also does growfs need patching so that it doesn't create a runt zone? I think we run the buffer verifier there, but a nicer check to abort early would be helpful. As would be a test case.