From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 9EEF43451D7; Tue, 19 Aug 2025 08:15:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755591341; cv=none; b=o9lWIb9pj9eI/xYm1vHRriKtJVOntbRjFdtII2zjrmSHOv+TjHSc3GMhdCVyiBSynO+OjjRamWi9kPlfqi4SUFWOhFl1vw+PmdzK4lY7tYLd/6ZQr8CKHOvpsxjKyo5bbBBUXb+FGZ/ynvMP0iHWTtb0BsUFIlbRI99eJMaTNXc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755591341; c=relaxed/simple; bh=k6y6AF54juU7kl6kbKvDXfrb4wSrYoD5+fTUFg6zBto=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=TUf3HTFqTTJJW13yLxHk6wRI7CkriWF0jOvnc8o4cq5jSZBBbG4USTrTnWEZ/+uAxjvxZAIP6IHYKcGbF2E59goAECSZppaaVuahZlMSf8MpG8IKRcknl+Me6hbROxwQNhoxFw9jA2EJSDbF169tK7YcjSl8dMKy2dpbdTLRRqI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=xM/wFLEe; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="xM/wFLEe" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=fRcvtU+W6HkjI1y5wLjk7QWRQYSRuxCjLLd23beixwY=; b=xM/wFLEeMOGcYpFv+dN0VueW/A TAHSYW6NlFW/ySvzvulmO4zXxTC3hsKn2cWEMzJHIZeZHtfo16WoZ/fkFl/B6EnYl3U3RD5Q3s55S Rnj0SFoFdtZrfncphbJ9d5Bz6JMvHdZuB2n+JSTth/njx+9ARiJtMY9g1rKZE2cXif8SBhgzh+mNF 7B7ROiBTMx5wK3RXf9VZpwKSkYH/ZiXdmj06DYuP3iGA0rEgUzmueUmUPy5LYU2iSU2Ob1f4kKD3a yglYDgygL4zKj69GwJZ8cT94WCx0o4NI5AzrzX8YnP+mr0TjHpq0GD//sCFe/AYj+Wj30jBKMgWCK tRjEZ8lg==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1uoHVM-00000009mHF-0bHD; Tue, 19 Aug 2025 08:15:40 +0000 Date: Tue, 19 Aug 2025 01:15:40 -0700 From: Christoph Hellwig To: Ethan Ferguson Cc: hch@infradead.org, linkinjeon@kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, sj1557.seo@samsung.com, yuezhang.mo@sony.com Subject: Re: [PATCH v2 0/1] exfat: Add support for FS_IOC_{GET,SET}FSLABEL Message-ID: References: <20250818174911.365889-1-ethan.ferguson@zetier.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20250818174911.365889-1-ethan.ferguson@zetier.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Mon, Aug 18, 2025 at 01:49:11PM -0400, Ethan Ferguson wrote: > That's fair. I took a look at how btrfs guards against this, it seems > as if they use mnt_want_write_file to guard against bad writes, and > only write to the in-memory superblock, and commit the transaction > afterwards. However, this (during my testing with > CONFIG_BLK_DEV_WRITE_MOUNTED both on and off) still results in an > immediate disk flush. > > My changes from this thread also seem to work with > CONFIG_BLK_DEV_WRITE_MOUNTED both disabled and enabled. What I meant to say is that we actually need your change to work with CONFIG_BLK_DEV_WRITE_MOUNTED, as the current way in tunefs is broken, even if that's something a few Linux file systems have historically done. > Maybe an alternative would be to only write to sbi->volume_label (with > mutex guarding), and only flush to disk on exfat_put_super? And to use > mnt_want_write_file as well. I think your patch is fine as-is. I've just been trying to give you additional ammunition.