From patchwork Mon Aug 26 16:36:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Charlie Jenkins X-Patchwork-Id: 13778152 Received: from mail-pg1-f173.google.com (mail-pg1-f173.google.com [209.85.215.173]) (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 172FB194C61 for ; Mon, 26 Aug 2024 16:36:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724690217; cv=none; b=X6W5dJlL8YjrwYA1Lvb3F+0yifwVeHa8dTgJo+lKtPB9s4nr+D4Jesgxq02IuSB4OMIkHej3lGYOf22MdR7hnQ4Bhh6K5fqWbGxmu2DYwnatE/PhnPxahD+HTaypqy4/FVmI6D3CnUX/zsyZFNLLe0+NWv0Tfz3cKUddDJwzg/o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724690217; c=relaxed/simple; bh=XqOUkInmaOdlhgabGcz+808CcLq83Htv813NZMtziMU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=lloalexnLgN1iM+wRPPjc46od14Aa93uAnyxN7o1Ob357e5TikjivzlMFw9ddiJfgjkM4wBxoOjEGoXR5a7o8eiDsdT5JMO+jqXrYmAfCUqR66DvUwIRJEh/guJkeHLe2QZKfswmE+EFshKQbIIVBTR037BuYN6BZENMvd+fGUE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com; spf=pass smtp.mailfrom=rivosinc.com; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b=EDXV1zIg; arc=none smtp.client-ip=209.85.215.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b="EDXV1zIg" Received: by mail-pg1-f173.google.com with SMTP id 41be03b00d2f7-70b2421471aso2745968a12.0 for ; Mon, 26 Aug 2024 09:36:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1724690215; x=1725295015; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=vwEY/VtoVmU+E8jst/8XYF4V03csuvmXOzOLHGK9FuU=; b=EDXV1zIgLnLIsTyJrsVcHikmcEtHV8bs2NTH79BXEQ1s90seWooWTiRyQmUiSgX6aF ZEg3/ICvo28IvM4Zu22GejB6g5aGAePAZsUrt/Rd0K9oSjgxgA+kEoyjiahIcSHxhx4j GlNJlqOE50WyFM7Ec6z3lAdUFThpECURWChMSzsBPoGVi2xwqBv1+VGNzVjfn6R9ovk7 JMqA+aH4qYkmshQ/YxyBSZgA1YjOyVQPbdnKQca/WMXEflIVU6G0RKhziPX+TnBkP+0z 3q3KEAuLAPnrxq9penCTGJF8rdGyLPcqbTGeyTH2ZEL3FvdpdnkcM5QyKEhr1A9ZTdIK p3jA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724690215; x=1725295015; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=vwEY/VtoVmU+E8jst/8XYF4V03csuvmXOzOLHGK9FuU=; b=Hn7iHFGcUQtkETfTpcWAyfiLRMRcRgAEg+GF+Xq6HHHCeW0fkFajFGEO8OKP6mHqUu LrrwO3uos1D9+/IcRIY0M2vbsLi0grZkDFtZjUKdPOROmyDylHnglpEne1M91pl8s3iZ mznUTrrOlCSmLTzvWx7MCXh89rsFJzD6voVXcp58FBh9J6Yi4RF5HfHF+3V3moYo6eEC tRpkOswY4lfJm9IOGdD0jrlHzn/Rd33yKzgJjWrqnKaAKZxZ9Fvg76hZ4eUmwjCjeFdC DgOfe79v0CsA6YCrXE30oBLmtFGqsQ7SS0BpXnWRIlFjdCO9Wl4hRMElCW0zueqEJkA0 PA4w== X-Forwarded-Encrypted: i=1; AJvYcCV20dMzvSTS80hWCjuBqIDDzAj4+bQUVZLNgg19Wt/ZDvY8NY7TiGNpP2gVl2EYDjACdL1Ew91D1q6ug1ExSPA=@vger.kernel.org X-Gm-Message-State: AOJu0Yxz0ocvntXCBaCraZQtmJhlyQrCxswEoYj8Qp87nUi1o8Umpx1p MMV0AgKEx5y3A1Q4ueoybuvGmtVqL9tdb2re8noXnwWblHyiOSp/6AVZUMAK6to= X-Google-Smtp-Source: AGHT+IG8QhmkiiyjHn7CNuzuO3cKEPwPnStUmNniRFxIT45XKmbFcpuLujqkeUl+VhROGvvkE85iNg== X-Received: by 2002:a05:6a21:3401:b0:1c6:a777:4cfa with SMTP id adf61e73a8af0-1cc8b475035mr8486714637.13.1724690215233; Mon, 26 Aug 2024 09:36:55 -0700 (PDT) Received: from charlie.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7143434052dsm7174708b3a.217.2024.08.26.09.36.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 26 Aug 2024 09:36:54 -0700 (PDT) From: Charlie Jenkins Date: Mon, 26 Aug 2024 09:36:45 -0700 Subject: [PATCH 1/3] Revert "RISC-V: mm: Document mmap changes" Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240826-riscv_mmap-v1-1-cd8962afe47f@rivosinc.com> References: <20240826-riscv_mmap-v1-0-cd8962afe47f@rivosinc.com> In-Reply-To: <20240826-riscv_mmap-v1-0-cd8962afe47f@rivosinc.com> To: Jonathan Corbet , Paul Walmsley , Palmer Dabbelt , Albert Ou , Shuah Khan , Yangyu Chen , Levi Zim , Alexandre Ghiti Cc: linux-doc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Palmer Dabbelt , linux-kselftest@vger.kernel.org, Charlie Jenkins X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1682; i=charlie@rivosinc.com; h=from:subject:message-id; bh=XqOUkInmaOdlhgabGcz+808CcLq83Htv813NZMtziMU=; b=owGbwMvMwCHWx5hUnlvL8Y3xtFoSQ9qZ9crHD5wOM37Qun7plPRMb+9NoTsZH2gXqZrrqPotV QpY5a7UUcrCIMbBICumyMJzrYG59Y5+2VHRsgkwc1iZQIYwcHEKwEQstzH8lbiy35Wr1fNig5vi i2+/j7/w4mc/YXtzUcOKwzUz5Mqf2zP8s8kSC61Yeb3Ztl4vi8N6j4Pw6Rm1q/s5plxPsLT+t/E EPwA= X-Developer-Key: i=charlie@rivosinc.com; a=openpgp; fpr=7D834FF11B1D8387E61C776FFB10D1F27D6B1354 This mmap behavior caused unintended breakages so the behavior has been changed. Signed-off-by: Charlie Jenkins --- Documentation/arch/riscv/vm-layout.rst | 16 ---------------- 1 file changed, 16 deletions(-) diff --git a/Documentation/arch/riscv/vm-layout.rst b/Documentation/arch/riscv/vm-layout.rst index 077b968dcc81..eabec99b5852 100644 --- a/Documentation/arch/riscv/vm-layout.rst +++ b/Documentation/arch/riscv/vm-layout.rst @@ -134,19 +134,3 @@ RISC-V Linux Kernel SV57 ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | modules, BPF ffffffff80000000 | -2 GB | ffffffffffffffff | 2 GB | kernel __________________|____________|__________________|_________|____________________________________________________________ - - -Userspace VAs --------------------- -To maintain compatibility with software that relies on the VA space with a -maximum of 48 bits the kernel will, by default, return virtual addresses to -userspace from a 48-bit range (sv48). This default behavior is achieved by -passing 0 into the hint address parameter of mmap. On CPUs with an address space -smaller than sv48, the CPU maximum supported address space will be the default. - -Software can "opt-in" to receiving VAs from another VA space by providing -a hint address to mmap. When a hint address is passed to mmap, the returned -address will never use more bits than the hint address. For example, if a hint -address of `1 << 40` is passed to mmap, a valid returned address will never use -bits 41 through 63. If no mappable addresses are available in that range, mmap -will return `MAP_FAILED`.