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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 3086FCD5BB3 for ; Fri, 22 May 2026 22:12:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7GwqEuPTd+MR1zy5VZznoGmeEK7GKNhmlvjLDNCzxYk=; b=C7iKkYfsLuhH+i4alGPLn2kUkr vaqKmerXi+nEVq/+BJ6ZMDMIm0+bnagDnx88q9k75+N6+aTjQa4Ca0eZbf0OT4208RBJ6oPZtWZa3 lP5JITQLSn7yDwXI3bDHZ+kSsGL04qZzvyJOefQOk7X+Obw6c5H+4zc+mToshIXGeKxcxEFrpdvtU 9zP3bRAIhSURzHCdcPf24qEgSuj7nR/E/5mEmgf5ZnPGaTp6ci6B476og6xKq+4I2/LeRmbEwe8He og/ZleQomLKaJ8Zd7in82YuRGbGF5WWOUcwKVERktPtSPndDCdiMpT8w6Jhrez2v1HCTZ28WYnKfT OilL+2Jw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wQY6A-0000000C5Ew-2GUM; Fri, 22 May 2026 22:12:06 +0000 Received: from fanzine2.igalia.com ([213.97.179.56]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wQY67-0000000C5Dh-10O3 for linux-arm-kernel@lists.infradead.org; Fri, 22 May 2026 22:12:05 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=7GwqEuPTd+MR1zy5VZznoGmeEK7GKNhmlvjLDNCzxYk=; b=jCYDm7SwyA+L3wNOxm1f+uSwAE +4vC4I+TruXzHAcmMB7sul7EBVJl60qJ6dMtGzvNYM0ej9kn9yz4LlVrS6DxBefc5a3ni36XRnXZ0 Yg7lmbmuMWqCTQtQ6ES3WHZc8tZuajOQpMZ/6AB21HmiGvIc7mMm6ZoIH/nsQ2ZRjiiO6Qy1zGHCD wi+erIveQtxha4Mg2otBnN4m4pdJqj6QC75CZzCIgfiDEVFVebVKjCKI1YUTCtVvNSS/642EnMiDO XSWHw/2wrFtzvNymlwH2qN3LmEQXd/9oE/hnw3UKNnuKXnVpwm0+2kQo5HOpC7QuLo5fx2qooD/dB ui9+8gqw==; Received: from [179.193.2.40] (helo=[192.168.15.100]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_128_GCM:128) (Exim) id 1wQY5M-0054gC-EM; Sat, 23 May 2026 00:11:16 +0200 Message-ID: <2db4a7df-4395-4e95-8ffc-d7043459b454@igalia.com> Date: Fri, 22 May 2026 19:11:07 -0300 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC v2 0/2] arm64: vdso: Implement __vdso_futex_robust_try_unlock() To: Sebastian Andrzej Siewior Cc: Catalin Marinas , Will Deacon , Thomas Gleixner , Mark Rutland , Mathieu Desnoyers , Carlos O'Donell , Peter Zijlstra , Florian Weimer , Rich Felker , Torvald Riegel , Darren Hart , Ingo Molnar , Davidlohr Bueso , Arnd Bergmann , "Liam R . Howlett" , Uros Bizjak , =?UTF-8?Q?Thomas_Wei=C3=9Fschuh?= , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, kernel-dev@igalia.com References: <20260424-tonyk-robust_arm-v2-0-db4e46f752cf@igalia.com> <20260428110054.oQNT-kMn@linutronix.de> Content-Language: en-US From: =?UTF-8?Q?Andr=C3=A9_Almeida?= In-Reply-To: <20260428110054.oQNT-kMn@linutronix.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260522_151203_573959_F2EA5126 X-CRM114-Status: GOOD ( 17.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Sebastian, Em 28/04/2026 08:00, Sebastian Andrzej Siewior escreveu: > On 2026-04-24 15:55:59 [-0300], André Almeida wrote: >> Hi folks, > Hi, > >> This is my take on implementing the new vDSO for unlocking a robust futex in >> arm64. If you don't know what's that, Thomas wrote a good summary, >> including the motivation for this work and the x86 implementation: >> >> https://lore.kernel.org/lkml/878qb89g7b.ffs@tglx/ >> >> There are some loose ends in my patchset so I'm sending as a RFC to ask >> some questions: >> >> - If the process is interrupted between the labels, we need to check the >> conditional flags and clear the op_pending address from the register. Using >> objdump I see that op_pending addr is being stored at x2, but I suspect that >> this isn't stable, so I need to figure out how to make sure that the address >> will always be stored in the same register. >> - So far I have implemented only the LL/SC version to make review easier, but I >> can do the LSE version as well. > > I am a bit behind here. In the meantime, were you able to check it with > https://lore.kernel.org/all/20260404093939.7XgeW_54@linutronix.de/ > ? Sorry for my delay. Yes, I had to do some modifications for the test (will reply to your patch) and spot one error in my patch, and now the test passes, thanks! Will send a v3 for this soon.