From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id bca6af71 for ; Mon, 25 Nov 2019 19:13:15 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id ACEA39C620; Tue, 26 Nov 2019 05:13:14 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id B2FF993D74; Tue, 26 Nov 2019 05:12:57 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="YarlvnlJ"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 8944293D74; Tue, 26 Nov 2019 05:12:55 +1000 (AEST) Received: from mail-ot1-f65.google.com (mail-ot1-f65.google.com [209.85.210.65]) by minnie.tuhs.org (Postfix) with ESMTPS id 117CF93D71 for ; Tue, 26 Nov 2019 05:12:55 +1000 (AEST) Received: by mail-ot1-f65.google.com with SMTP id 94so13620660oty.8 for ; Mon, 25 Nov 2019 11:12:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=62cS/lsAEWQBGihUgHr4z/1CXvxtMk2glCt5H4A4fUY=; b=YarlvnlJ38TnmHvs9jOCUXTPpKQM4pBCLrEvcwRxY+VEFx8bKNTiSxQrLAtDd/mwBX 5+grwfqYpD2wDtbnlJAqwSUcVdIFIV1nPdZn1GxN7f+om1iHz372o+repiTMuCHXUydT KmzAPlfgb5BaQMFeilM2MbC7iqdfaR4wlN46a1EIufs8Ndou+T634rQ3vaBQLhFHvJq7 e1zzk6aeJdaDNUQwuniEMlfs91GzRst0y5W2s4JP3h0FjFW1dyzaKNiHQbGa4w6mkwVB qi74GGpQGFEeZjQIM0lbXzeneqjOwdhC1i5MnRXHCkc/i6n+z85tZGPIGbM+UjmAHzbQ j1oA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=62cS/lsAEWQBGihUgHr4z/1CXvxtMk2glCt5H4A4fUY=; b=mvGjnQx8QFKYaFffDMSUGi5+UmAsAeayIJhKU3JVCxttOVBLcjdbNhtIEFdj4xyzD4 ezMhokt+MVXFuQQAmE5j+eXT533lOkoiDcczJsYFEoRtpkdVLRm0hL2ATWYP0ZvcRDcJ pTuqqdQzbcEe4wpxUZABwvm6CbzheMIWyNZcv6DQ4AiTYFCXgDfog6upMo4pdijfqHhc sJyiIR2dasP+2KSbQ1hPi/WBr2cn3dtoCn+fhG0gXo8VPMeZe4uvq43y3zd6tgoFpVn1 z2/6CAYVBxE8gVi8C0RP3XPd/w332cZv4M3eytd08+GHPKTEJgDX8ige9KClsosNXcZx wT5g== X-Gm-Message-State: APjAAAXyQj1n+7MOoSvcSnI0AaUmb7Wgc8UKCee7E4liov886M0G75gj 5K0xFGdTdg0VMIdv8YMWvUe4e89UcRZo8RK/GCk= X-Google-Smtp-Source: APXvYqyIUzz61F9xoQhtY+QzO5/V6NiYG1lCgl9uK/8nLRruWxXOKIyVUirI6GSmZvHM/1JHclDKuhf42lCVo0bZvaQ= X-Received: by 2002:a9d:7588:: with SMTP id s8mr21968635otk.300.1574709173903; Mon, 25 Nov 2019 11:12:53 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: ron minnich Date: Mon, 25 Nov 2019 11:12:42 -0800 Message-ID: To: Warner Losh Content-Type: text/plain; charset="UTF-8" Subject: Re: [TUHS] Irix on MIPS -- was kernel mode paged X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: TUHS main list Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" Ah thinks Warner, that was exactly what I was trying to recall. And I am reminded as well how overloaded the term 'paged' is ... but yeah, in this case, I was looking for examples where the kernel ran with essentially no mmu but user programs did. Note that on Alpha there was an identity mapped space with no MMU as well but that was only for PAL mode and firmware that used PAL mode (like LinuxBIOS). On modern systems we have RISC-V with the no MMU M mode, and I just got to thinking that running a kernel in M mode would be "what's old is new again" :-) Thanks On Thu, Nov 21, 2019 at 7:24 PM Warner Losh wrote: > > > > On Thu, Nov 21, 2019, 2:12 PM ron minnich wrote: >> >> I'm looking for a reference to any Unix ports where the kernel ran in >> a non-paged address space and user mode was paged. I could swear this >> was done at some point, and memory says it was on a soft-TLB system >> like the MIPS, to avoid TLB pollution and TLB fault overhead. >> >> But maybe I'm nuts. I am happy to hear either answer. > > > Mips had KSEG0 which didn't go through TLB and was mapped to physical memory. Some MIPS kernels ran in this space to avoid TLB issues... > > Warner