From owner-freebsd-stable@FreeBSD.ORG Fri Feb 27 18:39:34 2009 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 68B8A1065679 for ; Fri, 27 Feb 2009 18:39:34 +0000 (UTC) (envelope-from alan.l.cox@gmail.com) Received: from yx-out-2324.google.com (yx-out-2324.google.com [74.125.44.30]) by mx1.freebsd.org (Postfix) with ESMTP id 1D9CA8FC16 for ; Fri, 27 Feb 2009 18:39:33 +0000 (UTC) (envelope-from alan.l.cox@gmail.com) Received: by yx-out-2324.google.com with SMTP id 31so824688yxl.13 for ; Fri, 27 Feb 2009 10:39:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:reply-to:in-reply-to :references:date:message-id:subject:from:to:cc:content-type; bh=9RJM7uEfdA7BA8OGPm8elxK156gjXjRkhgwFGSLw3kY=; b=wFmFIVtr+hzXg4ZWe3GDey2Cw9gsfcNdnKXobXqTeKAcg4TCxTdMRBl05CNGAl4k9W D8AkR29E6OCnNBpFOmZ5PfEHdyQh16qQuso8JaKqFQ0drIBmHFIQYKkCjnSdNUxqZdX3 gSaEZWAPj6kA1kzpU5R/iBx3d9s9GcVC4xeAs= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:reply-to:in-reply-to:references:date:message-id :subject:from:to:cc:content-type; b=bopFZalMP2+CACu69r3IpO+Emijg8uiOcznpwKnH5Or+2Oid184dpYiuIfzt7RJhOj JZCUpRxUYf+h602daIMCs6DIUDmLi104+P7hZ/sb2UhQQFNa5yv7srIa9apN5FEC+qid ABffavXhXJLwqEmtTJgVpw4RLvpvYj4xgPubU= MIME-Version: 1.0 Received: by 10.150.122.18 with SMTP id u18mr4407643ybc.20.1235758279046; Fri, 27 Feb 2009 10:11:19 -0800 (PST) In-Reply-To: <200902271211.18423.jhb@freebsd.org> References: <20090227130830.GI51952@rambler-co.ru> <200902271026.15796.jhb@freebsd.org> <20090227162625.GO51952@rambler-co.ru> <200902271211.18423.jhb@freebsd.org> Date: Fri, 27 Feb 2009 12:11:19 -0600 Message-ID: From: Alan Cox To: John Baldwin Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable@freebsd.org Subject: Re: 7.1-STABLE does not boot after recent superpage support MFC X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: alc@freebsd.org List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 27 Feb 2009 18:39:35 -0000 On Fri, Feb 27, 2009 at 11:11 AM, John Baldwin wrote: > On Friday 27 February 2009 11:26:25 am Igor Sysoev wrote: > > On Fri, Feb 27, 2009 at 10:26:15AM -0500, John Baldwin wrote: > > > > > On Friday 27 February 2009 8:08:30 am Igor Sysoev wrote: > > > > Is anyone able to boot kernel with recently merged superpage support > ? > > > > I have csup'd world to > > > > *default date=2009.02.26.23.59.59 > > > > then rebuild world and kernel does not boot: > > > > > > > > FreeBSD 7.1-STABLE #4: Fri Feb 27 11:59:13 MSK 2009 > > > > XXXXXXXXXXXXXXXXXXXXX > > > > kernel trap 12 with interrupts disabled > > > > > > > > > > > > Fatal trap 12: page fault while in kernel mode > > > > cpuid = 0; apic id = 00 > > > > fault virtual address = 0x0 > > > > fault code = supervisor read data, page not present > > > > instruction pointer = 0x8:0xffffffff803b1d80 > > > > stack pointer = 0x10:0xffffffff80686ce0 > > > > frame pointer = 0x10:0xffffffff80686d00 > > > > code segment = base 0x0, limit 0xfffff, type 0x1b > > > > = DPL 0, pres 1, long 1, def32 0, gran 1 > > > > processor eflags = resume, IOPL = 0 > > > > current process = 0 () > > > > trap number = 12 > > > > panic: page fault > > > > cpuid = 0 > > > > > > > > And the message is cycled. The kernel does not boot despite > > > > vm.pmap.pg_ps_enabled value. > > > > > > This should now be fixed, apologies for the breakage. :( > > > > Thank you, your commit has fixed the bug. > > > > Now I have > > > > $sysctl vm.pmap.pde > > vm.pmap.pde.promotions: 518 > > vm.pmap.pde.p_failures: 4534 > > vm.pmap.pde.mappings: 0 > > vm.pmap.pde.demotions: 423 > > > > Does this mean that (518 - 423) * 2 = 190M are mapped via 2M pages ? > > I don't think that includes the direct map which uses 2M pages. I think > your > conclusion is correct, but alc@ would know for sure. > > -- > John Baldwin > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org" > These counts are cumulative. So, they don't really provide you with an instantaneous number of the active 2MB page mappings. Moreover, when a 2MB page mapping is destroyed in its entirety, for example, when exit()ing a process, that does not trigger a demotion. In other words, a promoted 2MB page mapping can cease to exist without a demotion occurring. You are correct that in RELENG_7 these counts don't say anything about the direct map. Alan