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 05E1A36A35A; Mon, 6 Jul 2026 19:04:10 +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=1783364652; cv=none; b=ezZ3C4KGhwsg0/3M3QBG7b+5kHrN03CvdY3MOKyLDC8r0DvYoK3uYQlZOLudBj/4Ab5Vc1CZ+at4xEKNGCXyNRfA+jcgEBSwoaA/6lPtTnJMLuRY/9xMufPaCluOhfPB59LQPPLYHCOiziZN0jzd9oHat7KMgEpU+jw9fafZGNs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783364652; c=relaxed/simple; bh=5RLGVNDU4DrZCMKu/FBMg+Wv3SGC379Wmbng5p/GOgs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=bHSlsBQ3WNM/DxpZusdS5DE7C0YTLyckJ5mjpt8BUnxisAFgj3NuRYuG86ZuEOoz2aJvGV62VcY5Y46XmQpO0nw37OCTij9iVz0BbdMhJKJIRVH4fDt0bt9fREAj81w7GmVs6kOmNOFUngKZyjHHe/QHMZ2i2CpdnuYFH42ZOj8= 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=KpAuzBeB; 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="KpAuzBeB" 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=nfQ9zgkT3aT8H14uNPHLZ8/j4bpyM4lzgfsqYe3S6Vc=; b=KpAuzBeBJtQ64gMrvuYN/20KRv zq/lmv0s3X0jJ7Jr0n9YSIX/WC9XRI5KFZRYy9Y02wnbDEywUXMugU8USNGZTsUlPp5wyZbxV2ly4 3U9pihOJ26YKM4PCrNeBcrqyHgMVksn/wNIe3aeGh+/3/MjeH07bUNz7whObLZso3IUEgVdz5Vl77 8B5IUmdc7CVlZW091q89uIQvg0wvPaxnk0DqARUO/BFhMMM26oma0LV85Cwpys/xUh2y2twkT7/aK a86HIfK1LkTrxQ7JCPlLnPN8h3Ho5UK5Uu9NrL5XnToj0xCQxcrICbBvA1PckDP1GKNtLW5Iihzb1 fk0si0Bw==; 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 1wgobf-009swn-HG; Mon, 06 Jul 2026 21:03:51 +0200 Message-ID: <39c3f5cb-5b56-423b-b679-eafc67bbf44f@igalia.com> Date: Mon, 6 Jul 2026 16:03:46 -0300 Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 1/5] arm64/entry: Unify user mode handling To: Catalin Marinas , Will Deacon , Thomas Gleixner , 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, LKML , linux-arch@vger.kernel.org, kernel-dev@igalia.com References: <20260705-tonyk-robust_arm-v4-0-e0fd0fa259d3@igalia.com> <20260705-tonyk-robust_arm-v4-1-e0fd0fa259d3@igalia.com> Content-Language: en-US From: =?UTF-8?Q?Andr=C3=A9_Almeida?= In-Reply-To: <20260705-tonyk-robust_arm-v4-1-e0fd0fa259d3@igalia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Em 05/07/2026 14:56, André Almeida escreveu: > Currently, arm64 has two functions to prepare and handle context switches > from userspace: arm64_syscall_enter_from_user_mode() and > arm64_enter_from_user_mode(). The only difference is that the later calls > rseq_note_user_irq_entry() that sets rseq.event.user_irq as true. > > To ensure that futex_fixup_robust_unlock() works correctly, unify the > handling from user mode functions into one that always calls > rseq_note_user_irq_entry(). > > Other architectures calls irqentry_enter_from_user_mode() for syscalls > and interruptions, that sets rseq.event.user_irq as well. > > Signed-off-by: André Almeida It turns out that this patch is not needed at all and futex_fixup_robust_unlock() is already working correctly for arm64. The user thread can't call a syscall in the middle of the vdso function.