From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GbZ97XCp" Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 006521989 for ; Fri, 8 Dec 2023 09:08:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1702055287; 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=geKb5s/2utc6piCF71zpvMcYTqfKwMoL8K14EkjCTh8=; b=GbZ97XCpkekqlIUsMu1enha2MQvl9oxToADOidey3PfGvh66Ld4XsvxTazLrZZCzDATb7/ /6A+3OgUTCWsYLyqLNrOt6P9CaAxp+dO0i9PwQ5lQVHRl05bWOeIrWPwWm3Gg7tGKYojmK N8ZB1zS3wALnDZVqig55N018gyyloPA= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-28-swUAJBaqPsmjIZT__OEkVg-1; Fri, 08 Dec 2023 12:08:02 -0500 X-MC-Unique: swUAJBaqPsmjIZT__OEkVg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C11A58820C5; Fri, 8 Dec 2023 17:08:00 +0000 (UTC) Received: from segfault.usersys.redhat.com (unknown [10.22.10.6]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 84F388CD0; Fri, 8 Dec 2023 17:08:00 +0000 (UTC) From: Jeff Moyer To: Jens Axboe Cc: Jann Horn , io-uring@vger.kernel.org, Pavel Begunkov Subject: Re: [PATCH 1/1] io_uring/af_unix: disable sending io_uring over sockets References: <170198118655.1944107.5078206606631700639.b4-ty@kernel.dk> <6d2d5231-4729-4783-bcc8-0d11396e30fb@kernel.dk> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 Date: Fri, 08 Dec 2023 12:08:00 -0500 In-Reply-To: <6d2d5231-4729-4783-bcc8-0d11396e30fb@kernel.dk> (Jens Axboe's message of "Fri, 8 Dec 2023 09:28:35 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 Jens Axboe writes: > On 12/8/23 9:06 AM, Jeff Moyer wrote: >>>> So, this will break existing users, right? >>> >>> Do you know of anyone actually sending io_uring FDs over unix domain >>> sockets? >> >> I do not. However, it's tough to prove no software is doing this. > > This is obviously true, however I think it's very low risk here as it's > mostly a legacy/historic use case and that really should not what's > using io_uring. On top of that, the most efficient ways of using > io_uring will exclude passing and using a ring from a different task > anyway. > >>> That seems to me like a fairly weird thing to do. >> >> I am often surprised by what developers choose to do. I attribute that >> to my lack of imagination. > > I think you stated that very professionally, in my experience the > reasonings are rather different :-) I thought you might like that. :) >>> Thinking again about who might possibly do such a thing, the only >>> usecase I can think of is CRIU; and from what I can tell, CRIU doesn't >>> yet support io_uring anyway. >> >> I'm not lobbying against turning this off, and I'm sure Pavel had >> already considered the potential impact before posting. It would be >> good to include that information in the commit message, in my opinion. > > It's too late for that now, but I can mention it in the pull request at > least. Thanks, Jens, much appreciated. Cheers, Jeff