From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 BE4353DBD64; Mon, 6 Jul 2026 22:42:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783377760; cv=none; b=ihbf4DcT3Vhmx7MDq8MG7jRRYGGQJZAUVc/F3ZJXXnk0UHAiZVnNxgHv3jTPhxCj50u2jch/rzk4Ra1+0MRGs6rkt788F2ycUTnMm/hh0jJsjKApiUdJH701xUH5GvWyTvZlqhJJP/AQa2jTn0bgoFcuHntBQCbls8V07Ck8rvo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783377760; c=relaxed/simple; bh=w0EtWQmOFuGYlOktmZFXRq5uqbKL740wcQ/qAectcG4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=j7EnTXKoYk00dqcuC1yo0sbYa/5mp4t8dc6IqI7kqSTfKoVJ2WlxWW6ztV154Izv/IM5TlqCErObTRD8KOmcxoIB7eoTnjPh1Acmc1D1z2oGt2C9eyNLYUNCxZoVfe7OLieYz1AE6bDRMcRJinK0wNZP6FSK9Uha44bB0DcE3qs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gPJqbUn/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gPJqbUn/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 383C11F000E9; Mon, 6 Jul 2026 22:42:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783377759; bh=xZiKOLbHFoacuaaPtuNj0XifToEMxvblEc8Ej328efs=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=gPJqbUn/zjuKChD+IymPhILtKmY3I6xHghAGYQxgdTFMeIMCXiZIKCM8MkPw/Rjtf 31frK6oJqZozUAKsPpTPy2X1yF+ns7vgJj+8My7C1+u7qUmpKvFrtfzcjutQCw/dSx Z/4yIyFVvuSNNWgH8chRFCtDX5oQlaO/TSEdP5tL0ahZB4ACkctwElq5YvBcQyMqyN F/IO+MWr1lpwz6LM5/zHA2n8m812lSynI/J5Xqnl9b7EZkeTqX1GIwXhwQUo7pVZ8a wPm+yDbuJyXzit5GBEe1XM9Da1aXVCPDiLkJRFZT4rcXva1DvQORQVS0sWwQCow7Uq Yir4z7xIh9u/w== Received: by pali.im (Postfix) id 76CA35D7; Tue, 7 Jul 2026 00:42:36 +0200 (CEST) Date: Tue, 7 Jul 2026 00:42:36 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Steve French Cc: Steve French , Paulo Alcantara , Ronnie Sahlberg , linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RESEND 07/11] cifs: Check if server supports EAs before trying to set it for WSL Message-ID: <20260706224236.4fm5ypvbq3z3fsqi@pali> References: <20260706184819.22124-1-pali@kernel.org> <20260706184819.22124-8-pali@kernel.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 Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: NeoMutt/20180716 If the server does not support EAs then setting the EAs (which is part of the creating WSL special file) would fail and so WSL special file would not be created. Major and minor numbers of char and block devices is stored in the EAs and therefore without EAs support, it is not possible to create and store char and block device nodes. On Monday 06 July 2026 17:33:42 Steve French wrote: > If this were purely Linux, without this patch what would happen with > creating special files if the server didn't support EAs. Would some > special files still work? > > On Mon, Jul 6, 2026 at 1:52 PM Pali Rohár wrote: > > > > WSL special files store information into EAs. When EAs are not supported > > on the server filesystem then fast fail in mknod_wsl() function. > > > > Signed-off-by: Pali Rohár > > --- > > fs/smb/client/reparse.c | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c > > index 99e93b56374f..e2ea59a17c9c 100644 > > --- a/fs/smb/client/reparse.c > > +++ b/fs/smb/client/reparse.c > > @@ -668,6 +668,13 @@ static int mknod_wsl(unsigned int xid, struct inode *inode, > > struct kvec reparse_iov, xattr_iov; > > int rc; > > > > + /* > > + * WSL special files store information into EAs. When EAs are not > > + * supported on the server filesystem then fast fail. > > + */ > > + if (!(le32_to_cpu(tcon->fsAttrInfo.Attributes) & FILE_SUPPORTS_EXTENDED_ATTRIBUTES)) > > + return -EOPNOTSUPP; > > + > > rc = wsl_set_reparse_buf(&buf, mode, symname, cifs_sb, &reparse_iov); > > if (rc) > > return rc; > > -- > > 2.20.1 > > > > > > > -- > Thanks, > > Steve