From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fout-a8-smtp.messagingengine.com (fout-a8-smtp.messagingengine.com [103.168.172.151]) (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 CA6851F936 for ; Wed, 19 Aug 2026 11:38:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=103.168.172.151 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787139530; cv=none; b=WDm7ttLEuPlrG0zg9kH5I2rVqt6X+u5RGvu2TP+SoI8eM6mg02xyXq8beoWEkH4g40Rc8TZxG+DCZAgLaEwbXCVQ0iS1TyC5nQY1zRoY8GBtjDe0tsE59M6EzKJmSuf0wQQpS2OcMAJAXcvfKR7Od9CIk+/8Qr5l8qqMq0KTIFA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787139530; c=relaxed/simple; bh=ouvUA9LNRtQE70QhHooOuClcS94FBvl+GFXCE+VOsy0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=jXwNyilurRbr+g62yqelv72YOBoJZwpIlwYDw7aKbuplUAVVH8DCJC0Zo495mdoLUKeCCMFTvjkn3l6nLV3asQELtrEw4o1ND/bQ+Mi30wqk4HYMpNVz1vIGG2azh4GH8SUZRSQ5ow5Hx72DAHQ/LPpfRANwDTbom3CZyOwQnQQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=bsbernd.com; spf=pass smtp.mailfrom=bsbernd.com; dkim=pass (2048-bit key) header.d=bsbernd.com header.i=@bsbernd.com header.b=h0kImjn2; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=KKQr+QDm; arc=none smtp.client-ip=103.168.172.151 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=bsbernd.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bsbernd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bsbernd.com header.i=@bsbernd.com header.b="h0kImjn2"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="KKQr+QDm" Received: from phl-compute-02.internal (phl-compute-02.internal [10.202.2.42]) by mailfout.phl.internal (Postfix) with ESMTP id DF9A9EC01C2; Wed, 19 Aug 2026 07:38:47 -0400 (EDT) Received: from phl-frontend-04 ([10.202.2.163]) by phl-compute-02.internal (MEProxy); Wed, 19 Aug 2026 07:38:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsbernd.com; h= cc:cc:content-transfer-encoding:content-type:content-type:date :date:from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to; s=fm2; t=1787139527; x=1787225927; bh=+6Fr2cGXTV0nsmJI30onKY9HSdaaPhAQJECr/eJZFf0=; b= h0kImjn2karVleEfKUIGoo0ZGJJnKABNgl82+8dR/U06eIT3QKmy+l5ypYPEWw3i 2zvFwK3gt/Tansg0Yb/iBkDFtzvsHPI/tZOZN1mtiQKjW8YXZx73NoB9zwyWJTSA cGDa0QIkEupKPOi9xGqQNhIFBVELko3bCLkwm5LAR6bX+riSxdnIlQ5rob57z20G yjL5goWijqwsp5ripWweAdYS2/t1zr6UjdApbxGaTjf1KsTTYT9iHhjyAkgN8yPD LMsG/4mMqlScHsOuAyMwYivaY9NgCsTUDp+8YLJWVmBPeLmMCnIP9EbE/Jiaz/GO /EfDpbgRpeyEsV6g5QC5ag== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:content-type:date:date:feedback-id:feedback-id :from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm3; t=1787139527; x= 1787225927; bh=+6Fr2cGXTV0nsmJI30onKY9HSdaaPhAQJECr/eJZFf0=; b=K KQr+QDmwH11N9BrcnK6WrV6QnoYe0I9W03yyQejnOURv45G3bw9Q++TxKHSKdm0l W6R9XdsQZQzrttaTHmPRw4PNjUe0l5ijLr5dLhTebATPJhB+ZPXIW9Ny1QSXSNaK eFJeNx2aXm83ru8lYpeLx76CMfU8cgI11UaVwiD7EjGkYLlszl6ua9xwv8BoBy97 RqacAc9h2wdC1hSv7/Ky/Pk3jmgIzOWKUvbhwT+yIBr/WxyMd3MROzhSwQ4LsYiq vk8mOuG3poeKdVy1y0EiMbJHSgrexGVZdRVlzpzyRqGs71ojkYMueG5J0s8FN5Wd 8MuPl0OPhAenN9v/kvadg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTEEYx6noitjdUzSHB6u1KXb6AtG2Px24H0m8ptwP8FCOiUvzbg5D/VVsLqM1U7SKB tDnQ594e/o9sqOIGGb3sTAv/p3XRjDm1u+jTIfWQh3DGJqRs+D+XDit0vLr3npWsioClC1 lRKURT9/7HoguHQiDvu4nY6BgdkEdldtKY8BpUUNmVcfC0+s3ekZzAobr05FbTzbN1VUB7 taVPdhc3CHYQHtup3MZsNUGncg4wsb2evbdGWto3sbYsPTeyzzFA4g1RFaPTuXnKq9Ll8y pYYqM2aBTCru+TMEJOUDmuLNtWkNMk3x841RFr2+A8o/uXjMUwj1OD1PItxSjsFfzLnWI3 QOqLYErcKBkBruynO7OUeqPBzMVFw6rbLXKcGSpQyuzY2JHd5IxNnlChlWB2LXTLLEL8Ag ZsvNs4tDfruitq/HAbXGfniBuyFsz7BMOVDTa+FOXc6/+fTu1WY1TEzp6D+9O+ae5WjOLL 7Vu9SVQy1VubF0uyS5S2rtimk2SOyJ44KdQRknB5xCBUOqjcwCs8PZRBCJYVGyjx50LgWN dfBR7OFSulzg3iaeCcR/B3eu3l6BD9R1j0S9uFXl2nTRTfTWSdAEi12Qh/DkHsID+h7raG Xgw0pe1NvsgQAptxy1zsyE8zWufCbOqb1YOxi140TDDwH8kw9nLcGknDPhyg X-ME-Proxy: Feedback-ID: i5c2e48a5:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 19 Aug 2026 07:38:44 -0400 (EDT) Message-ID: <4e085cc8-0a78-4ea5-89ec-ad425f6a38c6@bsbernd.com> Date: Wed, 19 Aug 2026 13:38:41 +0200 Precedence: bulk X-Mailing-List: fuse-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 1/6] fuse: decouple fuse_ring creation from ent registration To: Miklos Szeredi , Joanne Koong Cc: jlayton@kernel.org, libaokun@linux.alibaba.com, axboe@kernel.dk, amir73il@gmail.com, fuse-devel@lists.linux.dev References: <20260814185946.3679478-1-joannelkoong@gmail.com> <20260814185946.3679478-2-joannelkoong@gmail.com> From: Bernd Schubert Content-Language: fr, en-US, de-DE, ru-RU In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/19/26 13:34, Miklos Szeredi wrote: > On Fri, 14 Aug 2026 at 21:00, Joanne Koong wrote: >> >> Currently, the connection's fuse_ring is created lazily on the first >> FUSE_IO_URING_CMD_REGISTER command. A server registers entries from one >> thread per queue (one per CPU) and those threads issue their first >> REGISTER command concurrently. They then race to create the single >> per-connection fuse_ring, which required open-coded handling in >> fuse_uring_create() to detect and protect against concurrent creations. >> >> Decouple fuse_ring creation from ent registration and move it to >> FUSE_INIT reply processing after a server has negotiated and set >> FUSE_OVER_IO_URING. The ring is published before the connection is >> marked initialized. fuse_uring_register() no longer creates the ring and >> it instead uses the ring set up at init time. > > I tested this with loraw (a "raw" loopback tester that doesn't use > libfuse) and it fails with > > root@kvm:~# ./loraw -u /mnt/fuse > loraw: loraw.c:1010: lo_start_uring: Assertion `!cqe->res' failed. > > cqe->res is -22 (EINVAL). > > Attaching the reproducer. To compile: > > cp $(KERNEL_TREE)/include/uapi/linux/fuse.h fuse_kernel.h > gcc loraw.c -oloraw -luring Unless Joannes replies earlier, I will take a look in about 5 to 7 hours - reply expected in the night. Thanks, Bernd