From owner-freebsd-current@freebsd.org Thu Feb 28 22:48:39 2019 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 74F93151CC42 for ; Thu, 28 Feb 2019 22:48:39 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-qk1-x72d.google.com (mail-qk1-x72d.google.com [IPv6:2607:f8b0:4864:20::72d]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 6EF378DBD2 for ; Thu, 28 Feb 2019 22:48:37 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-qk1-x72d.google.com with SMTP id y140so13164570qkb.9 for ; Thu, 28 Feb 2019 14:48:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=TzO/PHSn23IQ46g+wbxjR7xovoFN2rwxg/6ruGxOnvA=; b=0BNbxHxoAw9V/psJgG/gMCxuGaavqyFe7juFCUHx+Tx7B94IsclI0r6ksURDvlu+Sy ElEZp0Pbzo70Wwy3GWkPGZn4otUj22zfNnxniR+hn6JqIZ/mX3X5yRbB2ygVwYxosoTo Hk+oOJJFvIHM/wyPomtVLtCjCOr92w0wVWn5dphRu/NS7dhxrHAyF01SBYicVaAvz9Xb 15czyGD4CosWe5bPbcN08aCFQd5YDSAUAysR2puvJE5H4b6Lw8E5rimjaDaBfA+b/0O1 srd1Vw44Ex7BdOuJtrEUhKafnyTzuPH0QRf3QXyVgrqBqrT7irW5jL6x5nQKDHnvKnvG q/aQ== 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=TzO/PHSn23IQ46g+wbxjR7xovoFN2rwxg/6ruGxOnvA=; b=VtvUzd9iKWF1ALNXzV8x3X+Um8Q62MUA+2e35CBUFr2jLHI0h9lBHI8XzTrbpVz91e QLM/pW56aZfGYSi1U70nYrff1D0yveiGZD7cA2wgpF2eQon6/jf4civAHeD+sHxhm2xr c/YMe9sqzW0Auf/lpdn5XdaD+j25Kkrrh+mUd/JVkygCqEvN7AQtoTEAJ+xPONWClAHY P1BKsoSMOFOkIDtXYLTw6vP8pULeU8S2mKtOPh2IhytHPNou/wIZyyIVANE62q9Hi3la tAWyf2Rw971Xz69Mlpw3KHk6tAe7T8+aR7J0DNt7dFpdx7mNMQF111SbjmZ6re1iYYjj nd2Q== X-Gm-Message-State: APjAAAX+vDDTi1dcUDbwFI4Dv+x9DwliQyitbaHTmMk3M6HhFeY1hVfF lesQbBpcvCbx5cszZR9QUa057XAsqNeMcemTR3JMsQ== X-Google-Smtp-Source: APXvYqzqAza+4OV56O0eG513/8QJVSzENsOXlAr0/QTGyT5u2LeqGnfK3sIYagsgvQcclfjBCiqJeErX1RjlhfsehVc= X-Received: by 2002:ae9:e702:: with SMTP id m2mr1580437qka.279.1551394116568; Thu, 28 Feb 2019 14:48:36 -0800 (PST) MIME-Version: 1.0 References: <20190222033924.GA25285@troutmask.apl.washington.edu> <20190222060410.GA25817@troutmask.apl.washington.edu> <20190223032644.GA14058@troutmask.apl.washington.edu> <20190223163947.GB18805@troutmask.apl.washington.edu> <20190228183214.GA17372@troutmask.apl.washington.edu> <866D86B4-6E47-46BA-BC4C-6E98DA94403E@cschubert.com> <947175c5-215b-c100-c6e7-c79a2322f98a@FreeBSD.org> In-Reply-To: <947175c5-215b-c100-c6e7-c79a2322f98a@FreeBSD.org> From: Warner Losh Date: Thu, 28 Feb 2019 15:48:25 -0700 Message-ID: Subject: Re: r343567 aka PAE vs non-PAE merge breaks i386 freebsd To: John Baldwin Cc: Cy Schubert , "Conrad E. Meyer" , Steve Kargl , freebsd-current X-Rspamd-Queue-Id: 6EF378DBD2 X-Spamd-Bar: ----- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=bsdimp-com.20150623.gappssmtp.com header.s=20150623 header.b=0BNbxHxo X-Spamd-Result: default: False [-5.61 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; R_DKIM_ALLOW(-0.20)[bsdimp-com.20150623.gappssmtp.com:s=20150623]; FROM_HAS_DN(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[multipart/alternative,text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-current@freebsd.org]; DMARC_NA(0.00)[bsdimp.com]; RCPT_COUNT_FIVE(0.00)[5]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[bsdimp-com.20150623.gappssmtp.com:+]; MX_GOOD(-0.01)[ALT1.aspmx.l.google.com,aspmx.l.google.com,ALT2.aspmx.l.google.com]; RCVD_IN_DNSWL_NONE(0.00)[d.2.7.0.0.0.0.0.0.0.0.0.0.0.0.0.0.2.0.0.4.6.8.4.0.b.8.f.7.0.6.2.list.dnswl.org : 127.0.5.0]; NEURAL_HAM_SHORT(-0.89)[-0.888,0]; R_SPF_NA(0.00)[]; FORGED_SENDER(0.30)[imp@bsdimp.com,wlosh@bsdimp.com]; MIME_TRACE(0.00)[0:+,1:+]; RCVD_TLS_LAST(0.00)[]; ASN(0.00)[asn:15169, ipnet:2607:f8b0::/32, country:US]; FROM_NEQ_ENVFROM(0.00)[imp@bsdimp.com,wlosh@bsdimp.com]; IP_SCORE(-2.71)[ip: (-8.76), ipnet: 2607:f8b0::/32(-2.71), asn: 15169(-2.03), country: US(-0.07)]; RCVD_COUNT_TWO(0.00)[2] Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Feb 2019 22:48:39 -0000 On Thu, Feb 28, 2019 at 12:46 PM John Baldwin wrote: > On 2/28/19 11:14 AM, Cy Schubert wrote: > > On February 28, 2019 11:06:46 AM PST, Conrad Meyer > wrote: > >> On Thu, Feb 28, 2019 at 10:32 AM Steve Kargl > >> wrote: > >>> This is interesting as well. Does this mean that amd64 is now > >>> the only tier 1 platform and all other architectures are after > >>> thoughts? > >> > >> This has been the de facto truth for years. i386 is mostly only > >> supported by virtue of sharing code with amd64. There are efforts to > >> promote arm64 to Tier 1, but it isn't there yet. Power8+ might be > >> another good alternative Tier 1 candidate eventually. None have > >> anything like the developer popularity that amd64 enjoys. > >> > >> Conrad > >> _______________________________________________ > >> freebsd-current@freebsd.org mailing list > >> https://lists.freebsd.org/mailman/listinfo/freebsd-current > >> To unsubscribe, send any mail to > >> "freebsd-current-unsubscribe@freebsd.org" > > > > We deprecated and removed support for 386 and 486 processors. We should > consider removing support for low end Pentium as well. I'm specifically > thinking of removing the workarounds like F00F. Are there any processors > that are still vulnerable to this? > > We have only removed support for 386 since it didn't support cmpxchg. We > still > nominally support 486s. I don't know how well FreeBSD 13 would run on a > 486, but > in theory the code is still there and the binaries shouldn't die with > illegal > instruction faults. > The biggest barrier to running on a real 486 is that it's hard for FreeBSD to fit into 32MB that was the maximum config you could have. You can barely boot it w/o tuning, though it will still fit a few jobs if you are looking at something super low-end with a lot of effort. There are a few later CPUs built on basically a 486 whose chipsets could support up to 128MB or 256MB which is enough to run FreeBSD still. Warner