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 82459FF8868 for ; Tue, 28 Apr 2026 11:01:11 +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:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=XBGhq8AsscvIj+mH9lal8kMT11cGW5WaUiLHhyEg9Cg=; b=k3c862JfSO6lbd3hdd1xkKMdtD iCspHObWeZWd8NWyAow2+nK91G8JvDoEr2xNNbSUKbfhZSYlwheeRc/3TlIvOX4qPvr9MNkSTPewK TPOmC0hgDW9yUQb79MtzcpB161hS9UWY9qiDcCwfb6kCWdg3TZ3JSXG2/icwVHkqJo0Z3Cd+UqmHx Fn6BpoX4zcWPZ6zYNWmHLjEJ2D0k2eCuG+us/a0TziO8oNE/NrI1xTbE623WV9gDZHbDZiukUNl4/ NWaImrHv79YGz/ZgYnIjP9NfQfQrOPWZgIktx1Rs/Ud2Of+y/usl5usgPSZhL/yJzYh2eZ4Par405 iKUO3QsQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wHgBc-00000001EXi-0YgJ; Tue, 28 Apr 2026 11:01:04 +0000 Received: from galois.linutronix.de ([193.142.43.55]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wHgBW-00000001EWU-0jDy for linux-arm-kernel@lists.infradead.org; Tue, 28 Apr 2026 11:01:03 +0000 Date: Tue, 28 Apr 2026 13:00:54 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1777374055; 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=XBGhq8AsscvIj+mH9lal8kMT11cGW5WaUiLHhyEg9Cg=; b=BnbLYkmMWIJt5VYkLwCdmQ60Q0X9uQlTWDCP7HP8/5OWBPyO5FaIv+KhxHC7SWW/fUPdqz +5GmE0FU/6RP0jFGAMKRpIKED1ulUDEQ1XZDeRcEnmfbHok4Wipd0or7EVnUP6vmQRn4nu dRRcQJE5gQwyYdrl9BDmpiW5WBl0h4KL1iZapdKnMQMG3uDKGV1f+5CmxsrfEBYUHeq4nm op2tVAUkJuFE1MyXvndOhSg5IOKNtZgLJh3+bl15iKUfNBdgkqZL4cn0eq72ogjoWmHsLu IDVMuW64PEGt1cd1h76IwXMnmiB+3dGtamdqFAPwpQQTSwvAnYjBDRxpAZAA1Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1777374055; 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=XBGhq8AsscvIj+mH9lal8kMT11cGW5WaUiLHhyEg9Cg=; b=7U9zG0CLn0w8edytSvhyGI+M4MTTmvpY2+kYhI/KmQsZDhYbNYFkRJC8CUSuEQOFCvFeoD Bcx9hNwDJNsf8/Cw== From: Sebastian Andrzej Siewior To: =?utf-8?B?QW5kcsOp?= Almeida 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 , Thomas =?utf-8?Q?Wei=C3=9Fschuh?= , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, kernel-dev@igalia.com Subject: Re: [PATCH RFC v2 0/2] arm64: vdso: Implement __vdso_futex_robust_try_unlock() Message-ID: <20260428110054.oQNT-kMn@linutronix.de> References: <20260424-tonyk-robust_arm-v2-0-db4e46f752cf@igalia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20260424-tonyk-robust_arm-v2-0-db4e46f752cf@igalia.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260428_040058_357054_8DC0F427 X-CRM114-Status: GOOD ( 16.90 ) 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 On 2026-04-24 15:55:59 [-0300], Andr=C3=A9 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: >=20 > https://lore.kernel.org/lkml/878qb89g7b.ffs@tglx/ >=20 > There are some loose ends in my patchset so I'm sending as a RFC to ask > some questions: >=20 > - If the process is interrupted between the labels, we need to check the > conditional flags and clear the op_pending address from the register. Us= ing > 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 add= ress > 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/ ? Sebastian