From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4EB734404A for ; Wed, 8 Jul 2026 03:11:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783480308; cv=none; b=NPYoGKWsSAEFJPCTDMAWOT/1cJf9ifqqpY2QSCbjIAfW8TvkCIfBLZahJ+BcDRcu6EC7quTXZ8xialBNe1bMvbQyGPVSZEBx3FunOtAOqNu8fJUPKOCaBunWLjKR5MNU99FrEw5QG+pbDvx0Qdic4sRTiH5tsv9jL0DecB5AUQk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783480308; c=relaxed/simple; bh=Zrti4GCHLz97fB1+AENv9p3We3wO+LWS+hXtRnrOQRA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=hPOBuDBxwPAs/Bl5Or73L/PyCWw68tcbho1kKPFa7NShQNvH/avHLF0qNu2KSNTRYO8b6UWHoThveNpPUiaC2W+E9AvS+K17jHxRKhONUZg8E9qiFnbDQO8SQGoU83TaZH00QDOkqSd2zB5YfQE4r1FclGKiNmTtPkEFeEUnumg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jthoughton.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=fRSuautM; arc=none smtp.client-ip=209.85.210.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jthoughton.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="fRSuautM" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-8423f544944so182569b3a.3 for ; Tue, 07 Jul 2026 20:11:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1783480305; x=1784085105; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=CZhq9cReoiqut1+GTjIpQFS6vd7poDNcxevd58JbT5Y=; b=fRSuautMdtXdAE4+hAM1QRCKoVDXaAiNFGRK4jb3MwDI36Mumf6n1IDjvlZRIxUVta 0zp6fFAyqB97vhSRdrKXCH6r1uT+tlnW3X1rq4bIJu99WWOcxI28zrpiTrACX+DX7o7o CdzJ6pvB/CYMqifIJQtQYFSYGHUZVXsWajwdJ4Qe2Fjn5TpjYnwyJaIJFf7nlLMI349j CIo8miRGH+0e6Xheku/4EG6MhozClY2QbVPv2i5uxX5QY8VT0DvtF2fM2kVSS0uWVlgt UPFAPg/0/a02Og7BS6B91yfS98xD8b5RAmAESO9/hzomYUsSCdCMHyLqZlxpMx0NawWS AU+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1783480305; x=1784085105; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=CZhq9cReoiqut1+GTjIpQFS6vd7poDNcxevd58JbT5Y=; b=Cw0iQwni+DHmvkaEmw3r2x7LCvvIbKfZt0qbB4k1dq4H+oC7BJ9sgO9QJSL3MD59gQ QWzuuGwW9WNU/lyPjYbDcsCvVGLh5n6J7cQuQ3nc6ldqoZ6xO76eLtjVVhSBQ88n6e/f DSoU7iPhGnN/DS+HeJzhiUxDI9pg+vQs3ZBn3T2oKsvxO0uyaJXQCqqiyLDoOXKEp1rA Z1WBBKdxzJwZhDFetJunDbVkcr1lqXYWa0osLqqv1HESN0+eg0TaOdxT8LSOqr5q63p5 ECUJSZhd4p3PFa8rHml0rMdy5uNosvhX1VFI785dlaqY4xTr50O4jQGFVQx0NYyZNfvL 7V/w== X-Forwarded-Encrypted: i=1; AHgh+RpSP4Wil1fnfZEXX+BoH5S9ZrMvMR5L6MmkdE6qMWfSrW20oU/FHgqzRuewRjs31HCyYFhcJmR08H6f0CQ=@vger.kernel.org X-Gm-Message-State: AOJu0YwwamCvBVlhkej1RHeOUCWRQG6ad/HjpCtWGiXY5NBBGmQTw0jW lA45OP56EosRywtACuukD7afBHTbedPDG9Sh8SUIOUyX1A7t6aa8HFCorleiKbYkz4WVjDGH0VY AWzfehn9QFnCwwlambs7CGA== X-Received: from pfes17.prod.google.com ([2002:aa7:8d51:0:b0:848:4733:fed1]) (user=jthoughton job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:39a8:b0:845:d285:3b6e with SMTP id d2e1a72fcca58-84842fce41amr674441b3a.58.1783480304616; Tue, 07 Jul 2026 20:11:44 -0700 (PDT) Date: Wed, 8 Jul 2026 03:11:23 +0000 In-Reply-To: <20260708031129.3503195-1-jthoughton@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260708031129.3503195-1-jthoughton@google.com> X-Mailer: git-send-email 2.55.0.795.g602f6c329a-goog Message-ID: <20260708031129.3503195-14-jthoughton@google.com> Subject: [PATCH 13/18] arm64: Drop BBML2_NOABORT requirement for HVO From: James Houghton To: Will Deacon , Catalin Marinas , Muchun Song , Oscar Salvador Cc: Nikos Nikoleris , Linu Cherian , Mark Rutland , David Hildenbrand , Andrew Morton , Ryan Roberts , Nanyong Sun , Yu Zhao , Frank van der Linden , David Rientjes , James Houghton , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Content-Type: text/plain; charset="UTF-8" With PMD updates being done with the Access Flag trick, BBML2_NOABORT is no longer needed. Dropping this requirement vastly widens the pool of systems this optimization is valid for. Intentionally leave HVO as opt-in, as enabling HVO still introduces the following regression: if all boot CPUs support HW AF, then any late-onlined CPUs that do not will not be onlined. Signed-off-by: James Houghton --- arch/arm64/kernel/cpufeature.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 3b9224b99a5f..c13433316e80 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -2175,11 +2175,10 @@ static bool has_bbml2_noabort(const struct arm64_cpu_capabilities *caps, int sco static bool hvo_compatible(const struct arm64_cpu_capabilities *caps, int scope) { /* - * We need BBML2 to support Block -> Table transitions without taking - * faults, and we need HW AF support to support changing the OA without - * taking faults. + * We need HW AF support to support changing vmemmap mapping level and + * OA without taking faults. */ - return cpu_supports_bbml2_noabort() && supports_hw_af(scope); + return supports_hw_af(scope); } static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused) -- 2.55.0.795.g602f6c329a-goog