From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E02DCEE2080 for ; Fri, 6 Feb 2026 10:12:20 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 976C083FE8; Fri, 6 Feb 2026 10:12:20 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id AVWGjhxN0MOB; Fri, 6 Feb 2026 10:12:18 +0000 (UTC) X-Comment: SPF check N/A for local connections - client-ip=140.211.166.142; helo=lists1.osuosl.org; envelope-from=intel-wired-lan-bounces@osuosl.org; receiver= DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 50AA683FE7 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osuosl.org; s=default; t=1770372738; bh=DhaAgJyKGpAxu69onmTYpr1zMQl+4LY07Xc1GM3wQlQ=; h=Date:To:Cc:References:From:In-Reply-To:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=RRZBi+bszG+3TkuaR9tqkjDG3V7ItyTC6fsOYO88RAkuAf13KHcGqLMhb7RXHuiLL f6SMirGvJdkkr0bj4/R2Pcq0omSBnbsQrhmP0fIK18CKqLMIs56XgOJ0DU2HFqiHTo OsiOyKiOz7YG8VtwIC/GF4Z6QbIfs34WKShZpsfKsC7CgQKnmyLWck5ZH9TLfoLtYa 5HEIMs0AYeLnXcGlFRV3uvWeSiPmuJTRWr8ZTlUareLb/H7EIbEtgN2fcAirf7UL0b C/NDAd8/2NygYvzYfSvmW5FPCe8d+VnUBnyVQ1T0erfJIo1Rq/bW8LRFOGN0xSW1i0 8TxmWv20H1tag== Received: from lists1.osuosl.org (lists1.osuosl.org [140.211.166.142]) by smtp1.osuosl.org (Postfix) with ESMTP id 50AA683FE7; Fri, 6 Feb 2026 10:12:18 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists1.osuosl.org (Postfix) with ESMTP id 9EC22173 for ; Fri, 6 Feb 2026 10:12:17 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 830636115A for ; Fri, 6 Feb 2026 10:12:17 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id kpRdEMYv5vCZ for ; Fri, 6 Feb 2026 10:12:16 +0000 (UTC) X-Greylist: delayed 63903 seconds by postgrey-1.37 at util1.osuosl.org; Fri, 06 Feb 2026 10:12:15 UTC DMARC-Filter: OpenDMARC Filter v1.4.2 smtp3.osuosl.org 471C660B1B DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org 471C660B1B Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2001:41d0:203:375::aa; helo=out-170.mta1.migadu.com; envelope-from=vadim.fedorenko@linux.dev; receiver= Received: from out-170.mta1.migadu.com (out-170.mta1.migadu.com [IPv6:2001:41d0:203:375::aa]) by smtp3.osuosl.org (Postfix) with ESMTPS id 471C660B1B for ; Fri, 6 Feb 2026 10:12:15 +0000 (UTC) Message-ID: <601f0c4b-52d8-4b60-96bf-f2d65f8073d8@linux.dev> Date: Fri, 6 Feb 2026 10:12:04 +0000 MIME-Version: 1.0 To: Willem de Bruijn , Sebastian Andrzej Siewior , Willem de Bruijn , Jakub Kicinski , Paolo Abeni , Eric Dumazet , "David S. Miller" Cc: "Loktionov, Aleksandr" , Kurt Kanzenbach , "Nguyen, Anthony L" , "Kitszel, Przemyslaw" , Paul Menzel , "Gomes, Vinicius" , "netdev@vger.kernel.org" , Richard Cochran , "linux-kernel@vger.kernel.org" , Andrew Lunn , "intel-wired-lan@lists.osuosl.org" , "Keller, Jacob E" References: <20260205-igb_irq_ts-v3-1-2efc7bc4b885@linutronix.de> <20260205100347.ssTBDAI_@linutronix.de> <6a0f4cbb-e8b3-4f0e-b7f1-7f9ca5cba97d@linux.dev> <20260205145104.iWinkXHv@linutronix.de> <66925f09-ef9f-4401-baec-7d4c82a68ce3@linux.dev> <20260205164341.pJvni8kA@linutronix.de> <76acd5cc-eb6f-4c56-a5e6-f6413736afbb@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Vadim Fedorenko In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1770372731; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DhaAgJyKGpAxu69onmTYpr1zMQl+4LY07Xc1GM3wQlQ=; b=s1hZQdPCFE8qhcU9pfJ34OOPrLOGMEaldYRioPOYeFAwkarsS9aJKjFZe1mnuBWM0/mgEF XMpM54KSCIaU4FlVnTqz3BzQBbPXVzzhVsYng3GqfFD+5XsqR/WpfOLetaMX15ajsu6wT+ P0mlT45JQxV26mer0sXRaGq9c0djpU0= X-Mailman-Original-Authentication-Results: smtp3.osuosl.org; dmarc=pass (p=none dis=none) header.from=linux.dev X-Mailman-Original-Authentication-Results: smtp3.osuosl.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=s1hZQdPC Subject: Re: [Intel-wired-lan] [PATCH iwl-next v3] igb: Retrieve Tx timestamp directly from interrupt for i210 X-BeenThere: intel-wired-lan@osuosl.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-wired-lan-bounces@osuosl.org Sender: "Intel-wired-lan" On 05.02.2026 21:41, Willem de Bruijn wrote: > Vadim Fedorenko wrote: >> On 05/02/2026 16:43, Sebastian Andrzej Siewior wrote: >>> On 2026-02-05 16:27:03 [+0000], Vadim Fedorenko wrote: >>>>> So the only thing that bothers me is the read_lock_bh() in >>>>> skb_may_tx_timestamp() which deadlocks if the socket is write-locked on >>>>> the same CPU. >>>> >>>> Alright. Now you make me think whether we should enforce OPT_TSONLY >>>> option on socket which doesn't have CAP_NET_RAW? Then we can get rid of this >>>> check, and in case sysctl was flipped off - drop TX timestamps as >>>> it's done now? >>> >>> This would "fix" this problem for all users which do deliver the >>> timestamp from their IRQ handler instead of napi. There are a few of >>> those… >>> This would be considered stable material, right? (despite the fact that >>> we have it for quite some time and nobody complained so far). >> >> cc: Willem as he is the author of the check introduced back in 2015. >> >> But it's more like a question to maintainers whether it is acceptable >> way of "fixing" drivers or it's no-go solution > > Requiring OPT_TSONLY unless CAP_NET_RAW would break legacy users. Well, they are kinda broken already. Without OPT_TSONLY and CAP_NET_RAW all TX timestamps are silently dropped. To receive these timestamps users have to get CAP_NET_RAW permission, and it will work with the updated logic as well...