From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from submarine.notk.org (submarine.notk.org [62.210.214.84]) (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 1914B22D7B5; Wed, 17 Dec 2025 21:49:31 +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=1766008174; cv=none; b=raTWjYf0mtclEJi5cNa3C77Re0KbJtyAfhWYrbD8y6JVuDHArZ6RKXLvzahOaLT2EDZwqB7YRf/Yo7+QZ/5N9ZP4Bslq/kI0ixLMzb6Se6eSZasvLIKvBeeyv9o8/nKKgxAa+dqxU1W5GY6U2LDDAnRLX28pdJWWCVR+efjYCzw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766008174; c=relaxed/simple; bh=pe6MD91KBXNGiAzgccXj8T+pTJoWLRrL5iFCNmLhSjI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qDkFBjYXCo7mGNwADt//ghRJnLq7bG2hwbNYcFTxBvjDwgfEIpuOho3MISHyX46xt3T1MfO2jkYihv1f1GlQz2cOLQ4l7P/aAkHh00tgd3RvPsP1cbiFaqUj/IShc1Sw+T78lWcIt5gTXXE4jJqv3i7EeVXEF4ZYTgXgM1oJ6N0= 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=qTJ1yVHV; 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="qTJ1yVHV" Received: from gaia.codewreck.org (localhost [127.0.0.1]) by submarine.notk.org (Postfix) with ESMTPS id DBCD114C2D6; Wed, 17 Dec 2025 22:49:20 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=codewreck.org; s=2; t=1766008163; 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=Rm0JYrpF7d0NcE2CiRu2ipHmE7x2XFoJEcDXDNz0kiM=; b=qTJ1yVHV9ta8kgjEQx1M9VNpZi6Ex+WOflXMZWwvIfAqXLy2vP1KGi7WNH5+0wfSYElTPO Dh2iULa3x8eVjXAsdYl18pT99qC+iSV7S4D8gL9yuo4zBY0sXMb9LrfHu6Vj6/l8tkSEqU 9gaJKSi3N0vOAhfY2IMzKi98tZGj1j/b9IJHhn6uoTIjjJ7jVH6CwKi8Wuz4+0iycDcwcd UQ94SvazkKdhRkLuhDhqIFBA5hsQcAMb3//x4auyn05s14ElqI5zzo0F+XAE1i3WniGK09 UuErgazzURIJ6EET0ya6gnYUAmRhalcfXgD3szsmA7j3Yfp7EbRqgIoyX2tQuA== Received: from localhost (gaia.codewreck.org [local]) by gaia.codewreck.org (OpenSMTPD) with ESMTPA id ce03f421; Wed, 17 Dec 2025 21:49:19 +0000 (UTC) Date: Thu, 18 Dec 2025 06:49:04 +0900 From: asmadeus@codewreck.org To: Christian Schoenebeck Cc: Eric Van Hensbergen , Latchesar Ionkov , Chris Arges , v9fs@lists.linux.dev, linux-kernel@vger.kernel.org, David Howells , Matthew Wilcox , linux-fsdevel@vger.kernel.org Subject: Re: [PATCH] 9p/virtio: restrict page pinning to user_backed_iter() iovec Message-ID: References: <20251210-virtio_trans_iter-v1-1-92eee6d8b6db@codewreck.org> <2332946.iZASKD2KPV@weasel> 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: <2332946.iZASKD2KPV@weasel> Christian Schoenebeck wrote on Wed, Dec 17, 2025 at 02:41:31PM +0100: > Something's seriously messed up with 9p cache right now. With today's git > master I do get data corruption in any 9p cache mode, including cache=mmap, > only cache=none behaves clean. Ugh... > With this patch applied though it gets even worse as I can't even boot due to > immediate 9p data corruption. Could be coincidence, as I get corruption > without this patch in any cache mode as well, but at least I have to try much > harder to trigger it. As said before don't bother with this patch, it's definitely wrong -- we can't just use data->kvec->iov_base for bvec or folioq iters, so there *will* be corruptions with this patch. I'll try to see if I can produce anything wrong with master... -- Dominique