From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f177.google.com (mail-pl1-f177.google.com [209.85.214.177]) (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 7089515884B for ; Tue, 9 Apr 2024 22:19:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712701191; cv=none; b=Rk818NOIkIOlL8jErmXPJiJMfdIpoufNyz0scbJhdNRtw/cju9FQMHaOeke1VopvZYEVH1+yxsZrsJHyBxifB9DrJ2H7OIpGlD4ZJslyS+Y57Cmjs1FuwShe3mf+cAGGYKXeSV7W9IkxlHuY15yQtsea2Cp6wbUfGyxtidGlCfc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712701191; c=relaxed/simple; bh=EYMsqegjT4OXpgUDL/2KYBA7Xq+Ay65w52yrQrkbRj4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=E3T3gt+kVHvQz/iP8FsjAUnFF9KaNF6Mz0AEN5FYaRFFKkMRBRvmQwd6EvMX6sFbLAdPTm9l728Di/Mm0cvapzQJdgMu4Nqth4lBxIHCK0VfR4bqwf2rfJI+kD0G2M7Uxs/NN7ioWTH/RpAfrCAZhE0RpaZm9Vd3LZc7RaPRXDY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=EkS3kAfm; arc=none smtp.client-ip=209.85.214.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="EkS3kAfm" Received: by mail-pl1-f177.google.com with SMTP id d9443c01a7336-1e3dda73192so22637065ad.3 for ; Tue, 09 Apr 2024 15:19:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1712701190; x=1713305990; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=dVGaEP7K5QMj4iEVzjXOSGPdsEqHFt6Mr5ict+7OkIA=; b=EkS3kAfm3b4tg5R0ENXz6MqqojkQDmkTIcn+4G7j29Pd4leFC1THFYzfl2xRFSAJyo vQINOf6H+q+RnxTUIFRcHdB994UNjBTgi1guHuCJtwc5Ae60hdlBcx6hbEhwOO8X95o5 g7r/zckXU3zj6QMeb4UlyzHTbz9rAuLUJPI10= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712701190; x=1713305990; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=dVGaEP7K5QMj4iEVzjXOSGPdsEqHFt6Mr5ict+7OkIA=; b=wv6iMXLMmskucxVVr45BuhSHU6HOD2KkSrC3wLTlBc4s2pBdOJLki/WdAhQJiXQVEj jFwN1K8dw0rsX6i5r2y9CzNMq54YObDslJTmmBTkkYeWA8rHHJCW06/2NIN9+Qa/erlh JViTq4Gxfl1m+zak7pS4TO1Q8+zHn2ogRmxRp1ii99e1Vutd9nIajB2vEWOZGMkel17x jhGK4Izk4KFfRGiIaNiqL9QY4Cru4FNOOoaghtnjF9Ga7k0wiRta5+ZYkcGLWla8jG+/ d2KMzfT4O7iOv7fV/ub0R0iZHQVxoJ1gAWmRD0ur98d5wKI9bY+FUKE9hX5uccboQq/0 KFeg== X-Forwarded-Encrypted: i=1; AJvYcCVDs9Rf1lkl82zN3wc6qe3RQMIDj9LDSOiWMVoWlt7jABm1+e5zXJlkoW2hc+yocBhrikulOOiLr5WdsbsL5XNZFGw/SD4yZUud4qdbz+TL3IdL X-Gm-Message-State: AOJu0YzV4d0c12H0FILsaRd3dcJS9CJuceHMFMai3jxKIUIbXb1R21K8 n4e7iym4B1GE75f3ZciIsqmlnImmW2Kaf3zpYJe7eFK/fvirbhV4V90bV8N8UQ== X-Google-Smtp-Source: AGHT+IEGUmXhtGH19b1H/WgCD2Rpis8vZRMumjN97SwnqzVkgy1CeZDYsMWyzkA9riCGUi1oxXbPcg== X-Received: by 2002:a17:903:2441:b0:1e4:1fb8:3216 with SMTP id l1-20020a170903244100b001e41fb83216mr1246750pls.52.1712701189791; Tue, 09 Apr 2024 15:19:49 -0700 (PDT) Received: from www.outflux.net ([198.0.35.241]) by smtp.gmail.com with ESMTPSA id b3-20020a170902650300b001e4ea358407sm205887plk.46.2024.04.09.15.19.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 09 Apr 2024 15:19:49 -0700 (PDT) Date: Tue, 9 Apr 2024 15:19:48 -0700 From: Kees Cook To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes , linux-mm@kvack.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Tony Luck , "Guilherme G. Piccoli" , linux-hardening@vger.kernel.org, Guenter Roeck , Ross Zwisler , wklin@google.com, Vineeth Remanan Pillai , Joel Fernandes , Suleiman Souhlal , Linus Torvalds , Catalin Marinas , Will Deacon Subject: Re: [POC][RFC][PATCH 0/2] pstore/mm/x86: Add wildcard memmap to map pstore consistently Message-ID: <202404091519.B7B2221@keescook> References: <20240409210254.660888920@goodmis.org> <20240409172358.34ea19f0@gandalf.local.home> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240409172358.34ea19f0@gandalf.local.home> On Tue, Apr 09, 2024 at 05:23:58PM -0400, Steven Rostedt wrote: > On Tue, 09 Apr 2024 17:02:54 -0400 > Steven Rostedt wrote: > > > memmap=12M*4096:oops ramoops.mem_name=oops > > I forgot to mention that this makes it trivial for any machine that doesn't > clear memory on soft-reboot, to enable console ramoops (to have access to > the last boot dmesg without needing serial). > > I tested this on a couple of my test boxes and on QEMU, and it works rather > well. I've long wanted a "stable for this machine and kernel" memory region like this for pstore. It would make testing much easier. -- Kees Cook