From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) (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 1B67B3264E7; Mon, 6 Jul 2026 19:03:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.97.179.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783364598; cv=none; b=pOQEiYOS2AN9wh4Uqy5inKS/nqz4HOh8qlEq55a9umawBppeFrTIoRWuj3/AIM0gc+ek4+JJ9s0HAV2C3DVmz8nlzkAHK6u4teb6xJe2tx8crXrN3ZcwnxvVg+RyRhKtAXjtF7FaqJnT2gDL+S0pqRZiDNTpTfQfomO+Hkxz5tM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783364598; c=relaxed/simple; bh=SZgwM355FagWdXRVFpFTnTC0f0jqRePuyssaX8ULq9E=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=JQElJiFt7X8++WdqkOeBZ4vZC1QvKUuPs9vqD6JQweW7YI+1v5C9e1DtRLJxCz6hnCUQfhllJg0IRxjanUCLZMZCDyrZBQBSRdVuS09xjEJgsM09srSBC+g7FTZi1yUWDuYMOTV0nFzuOaitS5lhgErhR4V3YvqNbWac5KiNfR0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=UeVAjPhI; arc=none smtp.client-ip=213.97.179.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="UeVAjPhI" 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=TulnqDkg59FUxryL3ptCGcm21LX3Mt6uGVOMyyGg9JE=; b=UeVAjPhIMhfIm2xnQeMe5orSBM uayF73MrVjbGWrJ25XxvjD2d25sNcK0zKrEuCZ82LjAw0ZU2VY2I+URjnSfvinmrbXu1YmDqqm6le lQnl1a2bJF9kSMa2iHXsJay31dO7/QtzAV/P26NJeLBC/YIMhr/eqLnc6nBh5BuA/p86n3A3KefI7 0S9+ugrrdYnUv7PBoJ/TnAP9FXIUHA+82RsgblFGeidTyscKAxv7hibM7s50UyhHsHXpxwOz/HWZz yjqf8JFo4bYrckHItBIeesMLfLAgznr2qV/vSng4KMoVZzw9xaImOty3UnWZrWV4nSv97nxlt04+A t0yEeGcw==; Received: from 189-68-33-146.dsl.telesp.net.br ([189.68.33.146] 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 1wgoaH-009svi-EM; Mon, 06 Jul 2026 21:02:25 +0200 Message-ID: <84ed46a8-54db-4f48-9d59-5c06cd020c03@igalia.com> Date: Mon, 6 Jul 2026 16:02:17 -0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 0/5] arm64: vdso: Implement __vdso_futex_robust_try_unlock() To: Thomas Gleixner , Catalin Marinas , Will Deacon , Mark Rutland , Mathieu Desnoyers , Sebastian Andrzej Siewior , Carlos O'Donell , Peter Zijlstra , Florian Weimer , Rich Felker , Torvald Riegel , Darren Hart , Ingo Molnar , Davidlohr Bueso , Arnd Bergmann , Uros Bizjak , =?UTF-8?Q?Thomas_Wei=C3=9Fschuh?= , "Liam R. Howlett" Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, kernel-dev@igalia.com References: <20260705-tonyk-robust_arm-v4-0-e0fd0fa259d3@igalia.com> <87qzlhjick.ffs@fw13> Content-Language: en-US From: =?UTF-8?Q?Andr=C3=A9_Almeida?= In-Reply-To: <87qzlhjick.ffs@fw13> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Thomas! Em 05/07/2026 17:23, Thomas Gleixner escreveu: > On Sun, Jul 05 2026 at 14:56, André Almeida wrote: >> As explained in the Testing section above, we developed a test that puts >> breakpoints in the code to test if a user code being interrupted really clears >> the op_pending pointer. This test wasn't initially working because of this check >> at futex_fixup_robust_unlock(): >> >> /* >> * Avoid dereferencing current->mm if not returning from interrupt. >> * current->rseq.event is going to be used subsequently, so bringing the >> * cache line in is not a big deal. >> */ >> if (!current->rseq.event.user_irq) >> return; >> >> rseq.event.user_irq was always false during my tests, and it prevents the fixup >> to happen. I figured out that arm64_syscall_enter_from_user_mode() was the >> issue because it doesn't set user_irq to true when the task comes from a >> syscall. > > I have no idea what you are babbling about. > > A syscall enter never sets user_irq to true. It's only set to true when > an interrupt/exception entry comes from user space, i.e. via > > irqentry_enter_from_user_mode() > rseq_note_user_irq_entry() > Sorry for the babbling, you are right. I got confused by analyzing the kernel stack trace after running the tests and wrongly thought that I spotted something missing. Please ignore patch 1/5. > No? > > Thanks, > > tglx >