From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232116AbhBFCvW (ORCPT ); Fri, 5 Feb 2021 21:51:22 -0500 Received: from mail-ed1-x531.google.com (mail-ed1-x531.google.com [IPv6:2a00:1450:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16296C08EE7E for ; Fri, 5 Feb 2021 16:40:11 -0800 (PST) Received: by mail-ed1-x531.google.com with SMTP id z22so11065763edb.9 for ; Fri, 05 Feb 2021 16:40:11 -0800 (PST) Date: Sat, 6 Feb 2021 00:40:08 +0000 From: Chris Down Subject: Re: [PATCH] tmpfs: Disallow CONFIG_TMPFS_INODE64 on s390 Message-ID: References: <20210205230620.518245-1-seth.forshee@canonical.com> <20210205160551.cf57c4293ba5ccb8eb648c11@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20210205160551.cf57c4293ba5ccb8eb648c11@linux-foundation.org> List-ID: To: Andrew Morton Cc: Seth Forshee , Hugh Dickins , Amir Goldstein , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , linux-mm@kvack.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org Andrew Morton writes: >Currently there is an assumption in tmpfs that 64-bit architectures also >have a 64-bit ino_t. This is not true on s390 which has a 32-bit ino_t. >With CONFIG_TMPFS_INODE64=y tmpfs mounts will get 64-bit inode numbers and >display "inode64" in the mount options, but passing the "inode64" mount >option will fail. This leads to the following behavior: > > # mkdir mnt > # mount -t tmpfs nodev mnt > # mount -o remount,rw mnt > mount: /home/ubuntu/mnt: mount point not mounted or bad option. > >As mount sees "inode64" in the mount options and thus passes it in the >options for the remount. > > >So prevent CONFIG_TMPFS_INODE64 from being selected on s390. > >Link: https://lkml.kernel.org/r/20210205230620.518245-1-seth.forshee@canonical.com >Fixes: ea3271f7196c ("tmpfs: support 64-bit inums per-sb") >Signed-off-by: Seth Forshee >Cc: Chris Down >Cc: Hugh Dickins >Cc: Amir Goldstein >Cc: Heiko Carstens >Cc: Vasily Gorbik >Cc: Christian Borntraeger >Cc: [5.9+] >Signed-off-by: Andrew Morton Either of the two ways presented looks fine to me, no real preference. Thanks! Acked-by: Chris Down >--- > > fs/Kconfig | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >--- a/fs/Kconfig~tmpfs-disallow-config_tmpfs_inode64-on-s390 >+++ a/fs/Kconfig >@@ -203,7 +203,7 @@ config TMPFS_XATTR > > config TMPFS_INODE64 > bool "Use 64-bit ino_t by default in tmpfs" >- depends on TMPFS && 64BIT >+ depends on TMPFS && 64BIT && !S390 > default n > help > tmpfs has historically used only inode numbers as wide as an unsigned >_ >