From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 904FF315D48 for ; Mon, 24 Nov 2025 16:17:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764001025; cv=none; b=dIWqTrZPZvs5uNTF8uxLWUMPC4ArCqgVH0gM7d+6+QTqJlRBoM1CKalBD4XzN01mx3CPpxHBy9Swb58YkTW5toKtG5TFOGpgHRKvUg2sSmOQtgnD3Ob6fUpY3wI3xpt9krFOCpN4wr9VURtG52tEFzE9IOMfYY7/Bt6gYOn/3HQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764001025; c=relaxed/simple; bh=VRAdbQkfvLzcdFuDi0ISeabfKTnUcesLbzm7TkuXSIU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=d61pz1xJCHu7Zkh8tqkUKiVJOOOLeKeSnvDx2s/WhhmiSYmh+P7e4/kfvxh5y3RtR0NK67ylvDIz6Xa+CKTpn33FrWFd5ftsotDootHGb5Wu0nu1XZm1Q3oNDzORFCt/oC45/BuvUvDORoibfzTMftlXNEWGz4I1UDjvzuQzt4M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2k4NyICJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="2k4NyICJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9FA63C4CEF1; Mon, 24 Nov 2025 16:17:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1764001025; bh=VRAdbQkfvLzcdFuDi0ISeabfKTnUcesLbzm7TkuXSIU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=2k4NyICJKa4Rgfns1Da8YiEdrQuzKgE9T4LDWDXPgIpyiQ+hNE8UsBcZbq1j+cfvh Lf8/FnUvu5xi19WUurokd2p0qZfyc4sGLt/q2fOT1r5FY8R3nN4SVtAxr5Soi4rG82 uDSivD4Sus88UzjL58ARWkUc/o71DvsGCb/nv1wU= Date: Mon, 24 Nov 2025 17:17:02 +0100 From: Greg KH To: Jane Chu Cc: tj@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE Message-ID: <2025112410-carnivore-anemia-e6eb@gregkh> References: <20251111202606.1505437-1-jane.chu@oracle.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: <20251111202606.1505437-1-jane.chu@oracle.com> On Tue, Nov 11, 2025 at 01:26:06PM -0700, Jane Chu wrote: > On an ARM64 A1 system, it's possible to have physical memory span > up to the 64T boundary, like below > > $ lsmem -b -r -n -o range,size > 0x0000000080000000-0x00000000bfffffff 1073741824 > 0x0000080000000000-0x000008007fffffff 2147483648 > 0x00000800c0000000-0x0000087fffffffff 546534588416 > 0x0000400000000000-0x00004000bfffffff 3221225472 > 0x0000400100000000-0x0000407fffffffff 545460846592 > > So it's time to extend /sys/kernel/mm/page_idle/bitmap to be able > to account for >2G number of pages, by raising the kernfs file size > limit. Wait, we are having sysfs files that are bigger than >2G? Which files exactly? > Signed-off-by: Jane Chu > --- > fs/kernfs/mount.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c > index 76eaf64b9d9e..3ac52e141766 100644 > --- a/fs/kernfs/mount.c > +++ b/fs/kernfs/mount.c > @@ -298,6 +298,7 @@ static int kernfs_fill_super(struct super_block *sb, struct kernfs_fs_context *k > if (info->root->flags & KERNFS_ROOT_SUPPORT_EXPORTOP) > sb->s_export_op = &kernfs_export_ops; > sb->s_time_gran = 1; > + sb->s_maxbytes = MAX_LFS_FILESIZE; What is the default setting for s_maxbytes today? thanks, greg k-h