From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=198.137.202.133 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793202878; b=tNy3q9+vcYh5YU+c6p9La1jvU6v2225nCp/FLf9DYY2We2v6IFO/klAwqbpj9ZaibNJ4 BDWYn6oBNrKVfIPFcJxkxCnQ3E/jNBOu14aWo3KRAc4xD9+7gudGeRPVGiO3RlzbTPAOH 3payp9LZIfIKHEtQjjmWXlSUShb8esfBXA13zyBg2FL4DyEHwFyyopRTr30ABCok/5NQl gvqK8kHFf61Vzr2js5GhUEboKfFerkvIByDns5nV2x2jxU3zplgWLPAj8hf3y3P4CgUm3 jHlaA7F3xeGk+CTZ4CbFWuumv/j0IHmlh5BYnoYhUs6snb7mqIQ8woh2OWwfApxao/g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793202878; h=DMARC-Filter:DKIM-Signature:Received:Date:From:To:Cc:Subject: Message-ID:References:MIME-Version:Content-Type:Content-Disposition: In-Reply-To:X-SRS-Rewrite; bh=422HFN53Nwu1wgQaRKxujkAntjQ1/boKZzysS2TQQLk=; b=l8rXBZ732Ndf9R21i0ACcl15kty7P55PZvD5liwINEjGJAUggNQAMGwE1bXPQ4svoXnv BBxtDFaB0YbmefJOabloZGUDtHPxNmevaSlx1Nq99ZuGtn3sHDpIWTLHEpEQ7wRsVDFj+ vCIeDlbz204kMkWWMnu8eMBQa5xP2h3GFCrTj5Pse9FLiNw8HTregaCJ53fXg9mI9n6Yi HeXiNDv9ih/apHGi/sGPQHLsBrlINEnt/gbeFPYf7uaZm9gtr+TYgrd/RZ8eXp2HIuK9i Yau0ZfUc8Q1ziVF3D1cEs1e5BUFFKozvA5N8/wZBJkUB4bbYV22n7MAClJ2tiEQvBjw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=Mc4HRCpv; arc=none smtp.remote-ip=198.137.202.133 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E3C41606A31F; Wed, 28 Oct 2026 15:54:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org E3C41606A31F 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, unprotected) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=Mc4HRCpv 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=422HFN53Nwu1wgQaRKxujkAntjQ1/boKZzysS2TQQLk=; b=Mc4HRCpvDrCW9WLE2/g8ziQ7hT qO4gECc7MZn81ADg1ZeptLLUknbNXHkjuG2egQFOzO+D3I5y6BDvWQbaH8NmptdODVAOkjtuagxRj h1bNltaq2C6vsgV/5Nek9/evtQgcLWdrUZGK4/pyETMT3RPtqetOJkSRToHQX6hiFg2BPxyo//sY7 ZKny6Pb+0TECmITg60qJK88APogNvVcsC0xuCHiyDEZpYTaMd7ZS8fAb7/B+l9HMNXifreRLDJvAd luJvJqBJHH3iAlxOB8gwwAku1fwv9s4v4G8WG+msY+T4I1ZMdt1E0g1pJ5fOdnvlK8jAXZl+fA5Ef pl5bZqqg==; Received: from hch by bombadil.infradead.org with local (Exim 4.100.1 #2 (Red Hat Linux)) id 1xM5z3-00000007THx-1ie4; Wed, 28 Oct 2026 15:54:37 +0000 Date: Wed, 28 Oct 2026 08:54:37 -0700 From: Christoph Hellwig To: Jeff Layton Cc: Zorro Lang , fstests@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH RFC fstests] generic: add a test for multigrain timestamps Message-ID: References: <20261027-mgtime-v1-1-ec68914a116e@kernel.org> X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261027-mgtime-v1-1-ec68914a116e@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Oct 27, 2026 at 09:58:50AM -0400, Jeff Layton wrote: > Ensure that the mtime and ctime apparently change, even when there are > multiple writes in quick succession. Since this is opt-in for in-kernel > filesystems and there is no way to test for this feature in userland, > limit it to just ext4, f2fs, btrfs, tmpfs and xfs for now. > > Signed-off-by: Jeff Layton > --- > I'd like to start testing this to make sure it doesn't break, but it's > not universally supported on all filesystems. Is an explicit allowlist > like this the right approach? Can we please expose the fact that multi-grain timestamp are supported from the kernel? This seems like it would be just one bit we'd need in sttx or something similar.