From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from submarine.notk.org (submarine.notk.org [62.210.214.84]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E67772EC081; Wed, 22 Oct 2025 05:38:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.210.214.84 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761111520; cv=none; b=m4epSCHvgM7Dm71hBIY77k9ZhZ8jfq382zkR4CzBueWNMnatI+m31042PiGo/1CbP/KD3PpFrtTwRh/RkdXHcYaU5zt1gPjg4gtEYLarbH920/ZT4gvCJnmbswoKQqeGUcdRKz9hzgtWUVw5eb7/WUr9AEIyPJLn2Q2qShbrfVQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761111520; c=relaxed/simple; bh=UCQR+aT3yopHWQ+fBkDsxTQA8UU1mrskcwvqVTuyKt4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QNN5tHNhRHvVj640LUagYORrsjgISyi909bngDf8yKOyu1uFcW5BMAkxYWAxjbx/nE2mntTh4dkH3VO3oUX+zyF6crortxP0eZ//rTne72ARHQxmGlWIPPubVOLOu3gnD5S8koB5wqD/sG8NoXNP0WzLYYh3xFPQoYBpOjyHczg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codewreck.org; spf=pass smtp.mailfrom=codewreck.org; dkim=pass (2048-bit key) header.d=codewreck.org header.i=@codewreck.org header.b=UNktbWJm; arc=none smtp.client-ip=62.210.214.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codewreck.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=codewreck.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=codewreck.org header.i=@codewreck.org header.b="UNktbWJm" Received: from gaia.codewreck.org (localhost [127.0.0.1]) by submarine.notk.org (Postfix) with ESMTPS id 4081C14C2D3; Wed, 22 Oct 2025 07:38:31 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=codewreck.org; s=2; t=1761111514; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=OPgNsOT2ZO9umiexmnUVC6FxF44CE2Et1XNZVAkmI3Y=; b=UNktbWJmMVmAiO6elXuW5rxb14r0OOg3jKIKPHPdDxEWWFmJjwL/eFilcCtA+xSPBuTcCa DtIrAC4MA4vLPrETboYsfb/3FCuML+eAORUmnO9uQc275gbR5oAEvVxI2Fxa9ZSSdGA0pB U+HYZiiYdYF4she1+Ls5WUcuh43HcXjYtV/r593e0yLzcsua3dOqX3+LkuuoSHB56uCzbO C3wGgXxdbge8bp8RRH2r1C2fG+m4THEjlNhKznhAj5Fs6u79b3/s2WQVCImyn1jzS7tEWn eQC/MSpOirheEGIwvCDNFNo1NulIPeUuOcDrDKlK87yyIPqT8syQCCU1/AWhOA== Received: from localhost (gaia.codewreck.org [local]) by gaia.codewreck.org (OpenSMTPD) with ESMTPA id 1b0779e1; Wed, 22 Oct 2025 05:38:29 +0000 (UTC) Date: Wed, 22 Oct 2025 14:38:14 +0900 From: Dominique Martinet To: Linus Torvalds , Tingmao Wang Cc: Song Liu , Andrii Nakryiko , Eric Van Hensbergen , Latchesar Ionkov , Christian Schoenebeck , Alexei Starovoitov , linux-kernel@vger.kernel.org, v9fs@lists.linux.dev, bpf@vger.kernel.org Subject: Re: [GIT PULL] 9p cache=mmap regression fix (for 6.18-rc3) Message-ID: References: <20251022-mmap-regression-v1-1-980365ee524e@codewreck.org> <39116c81-1798-4cc1-945c-a05d0ac7d8d9@maowtm.org> 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=utf-8 Content-Disposition: inline In-Reply-To: <39116c81-1798-4cc1-945c-a05d0ac7d8d9@maowtm.org> Tingmao Wang wrote on Wed, Oct 22, 2025 at 12:34:13AM +0100: > On 10/22/25 00:16, Dominique Martinet wrote: > > We had a regression with cache=mmap that impacted quite a few people so > > I'm sending a fix less than a couple of hours after making the commit. > > > > If it turns out there are other side effects I'd suggest just reverting > > commit 290434474c33 ("fs/9p: Refresh metadata in d_revalidate for > > uncached mode too") first, but the fix is rather minimal so I think it's > > ok to try falling forward -- let me know if you prefer a revert and I'll > > send one instead (there's a minor conflict) > > See the reply to the original patch [1] (posted right after, and before > seeing, this message) - there is indeed more side effects, and I wouldn't > mind a revert for now. 0172a934747f ("fs/9p: Invalidate dentry if inode > type change detected in cached mode") will need to be reverted too. (yeah, and even that conflicts due to the added debug message in the next commit, but I went the heavy-handed way and removed the conflicting hunk so that commit's also implicitly been removed. In hindsight it would have been cleaner to revert the three commits 290434474c33^..c667c54c5875 -- ohwell) > [1]: https://lore.kernel.org/v9fs/6c74ad63-3afc-4549-9ac6-494b9a63e839@maowtm.org/ OK, so let's go with the revert for now as I don't have time to look for more corner cases immediately. Linus, here's the new PR: --------- The following changes since commit 211ddde0823f1442e4ad052a2f30f050145ccada: Linux 6.18-rc2 (2025-10-19 15:19:16 -1000) are available in the Git repository at: https://github.com/martinetd/linux tags/9p-for-6.18-rc3-v2 for you to fetch changes up to 43c36a56ccf6d9b07b4b3f4f614756e687dcdc01: Revert "fs/9p: Refresh metadata in d_revalidate for uncached mode too" (2025-10-22 14:25:27 +0900) ---------------------------------------------------------------- Fix 9p cache=mmap regression by revert This reverts the problematic commit instead of trying to fix it in a rush ---------------------------------------------------------------- Dominique Martinet (1): Revert "fs/9p: Refresh metadata in d_revalidate for uncached mode too" fs/9p/vfs_dentry.c | 10 ++-------- fs/9p/vfs_inode.c | 8 +------- fs/9p/vfs_inode_dotl.c | 8 +------- 3 files changed, 4 insertions(+), 22 deletions(-) -- Dominique Martinet | Asmadeus