From owner-svn-src-stable-9@FreeBSD.ORG Thu Feb 23 22:34:45 2012 Return-Path: Delivered-To: svn-src-stable-9@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 248A5106564A; Thu, 23 Feb 2012 22:34:45 +0000 (UTC) (envelope-from jkim@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id 133288FC0A; Thu, 23 Feb 2012 22:34:45 +0000 (UTC) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.4/8.14.4) with ESMTP id q1NMYi6t029441; Thu, 23 Feb 2012 22:34:44 GMT (envelope-from jkim@svn.freebsd.org) Received: (from jkim@localhost) by svn.freebsd.org (8.14.4/8.14.4/Submit) id q1NMYiuW029439; Thu, 23 Feb 2012 22:34:44 GMT (envelope-from jkim@svn.freebsd.org) Message-Id: <201202232234.q1NMYiuW029439@svn.freebsd.org> From: Jung-uk Kim Date: Thu, 23 Feb 2012 22:34:44 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org X-SVN-Group: stable-9 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r232088 - stable/9/sys/amd64/amd64 X-BeenThere: svn-src-stable-9@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for only the 9-stable src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Feb 2012 22:34:45 -0000 Author: jkim Date: Thu Feb 23 22:34:44 2012 New Revision: 232088 URL: http://svn.freebsd.org/changeset/base/232088 Log: MFC: r231781 Some BIOSes are known for corrupting low 64KB between suspend and resume. Mask off the first 16 pages unless we appear to be running in a VM. This address may be overridden by 'hw.physmem.start' tunable from loader. Modified: stable/9/sys/amd64/amd64/machdep.c Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/amd64/amd64/machdep.c ============================================================================== --- stable/9/sys/amd64/amd64/machdep.c Thu Feb 23 22:29:36 2012 (r232087) +++ stable/9/sys/amd64/amd64/machdep.c Thu Feb 23 22:34:44 2012 (r232088) @@ -1352,7 +1352,7 @@ getmemsize(caddr_t kmdp, u_int64_t first { int i, physmap_idx, pa_indx, da_indx; vm_paddr_t pa, physmap[PHYSMAP_SIZE]; - u_long physmem_tunable, memtest; + u_long physmem_start, physmem_tunable, memtest; pt_entry_t *pte; struct bios_smap *smapbase, *smap, *smapend; u_int32_t smapsize; @@ -1440,8 +1440,19 @@ getmemsize(caddr_t kmdp, u_int64_t first /* * Size up each available chunk of physical memory. + * + * XXX Some BIOSes corrupt low 64KB between suspend and resume. + * By default, mask off the first 16 pages unless we appear to be + * running in a VM. */ - physmap[0] = PAGE_SIZE; /* mask off page 0 */ + physmem_start = (vm_guest > VM_GUEST_NO ? 1 : 16) << PAGE_SHIFT; + TUNABLE_ULONG_FETCH("hw.physmem.start", &physmem_start); + if (physmem_start < PAGE_SIZE) + physmap[0] = PAGE_SIZE; + else if (physmem_start >= physmap[1]) + physmap[0] = round_page(physmap[1] - PAGE_SIZE); + else + physmap[0] = round_page(physmem_start); pa_indx = 0; da_indx = 1; phys_avail[pa_indx++] = physmap[0];