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 D12C52E88A7 for ; Mon, 27 Oct 2025 08:14:05 +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=1761552847; cv=none; b=Xld+NQtNE/IeBSxzWDPwvCxWODZ4EKMiayhuH7GbI37h8kOlRRiG86nlc63zN6CbTibb3KO6fjHG+SdC7nljaM5Jrp816ZcwOLboA1z6XRwxwOlV4zAs2wgbmAOAFy8EE0CT9wgwQMM1V8QmXiOR4BAmN9yBxpif3nqlBJY+Q4k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761552847; c=relaxed/simple; bh=zeyTZpMznlOHRFFkZzvUVcB/vrezPLFDlpYnnjnpC6Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=nbkuTtkAN2kTYyDXubZ6UvRkOzFS/H7oT8cmX37SF3JzjZJPDZic0uvugTkwV+3APKnWQ4yzEcTEE7hi/bvcw9IL7clJUhZFTWyacPZWxyUXiMVvbrqgp1zi4jii0xr6OD9vfIhWeRk2J9s315kRzcfFYBPfflSKWpJqKOgs4q4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (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=uqVG721R; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (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="uqVG721R" 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=DmDZzJBMn2K26k1b9Xq8OOnLWqHx6fOLD+CasJ2tmlg=; b=uqVG721RFgTB9KFxSd+/FCnUnA yWl2uWFHY6QE8FCuOJiE3W+uJpVSXY2HFlslru+cIoWOgQMOVlpsB7dyN33cCx5ByyziYhEDiyYnJ byIF2ZF7ohUkNb6lrmVZJWdQT2J0TSeqSCQU6WQtLjJUSg3NkaXhUSCSkCpTYs7XzC8rnFX9R7CMw JhGjzHeb8wmucyXGwj9EZSmULhxnfDrZtpuhZyhfD5l18nAHgbLZgQ1zKhGGrILc3a8D/OW1cxNAV pz1XhGzxjVWMXS1MBXZ3aIweAILgepPS8oSJx6oYlmq62xtNsbwvE4fRxQDYy568Ap8J0gHFiobP0 f6viiuUw==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vDIMd-0000000DKf5-1mEc; Mon, 27 Oct 2025 08:14:03 +0000 Date: Mon, 27 Oct 2025 01:14:03 -0700 From: Christoph Hellwig To: Mike Snitzer Cc: Chuck Lever , NeilBrown , Jeff Layton , Olga Kornievskaia , Dai Ngo , Tom Talpey , linux-nfs@vger.kernel.org, Chuck Lever , Christoph Hellwig Subject: Re: [PATCH v7 14/14] NFSD: Initialize separate ki_flags Message-ID: References: <20251024144306.35652-1-cel@kernel.org> <20251024144306.35652-15-cel@kernel.org> Precedence: bulk X-Mailing-List: linux-nfs@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: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Fri, Oct 24, 2025 at 04:37:31PM -0400, Mike Snitzer wrote: > Particularly because any filesystem NFSD is writing to _can_ also > fallback to using buffered IO if O_DIRECT set (NFSD is doing exactly > that). Which we _know_ (from Christoph) that having O_DSYNC set is > important when we fallback to using buffered IO (like we do for the > misaligned head and/or tail). No, I still don't know why any sync behavior is needed. I've been explaining how the sync behavior works at lot lately, but I still don't understand why we think we need it.