From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: [PATCH] xen: update machine_to_phys_order on resume Date: Tue, 12 Jul 2011 18:43:42 +0200 Message-ID: <20110712164342.GA12867@aepfle.de> References: <20110701104148.GA32729@aepfle.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <20110701104148.GA32729@aepfle.de> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Migration of pv guests fails, the guest crashes on the target host once the guest is unpaused after transit. It happens when the guest is started on a small systen, then migrated from that small system to a large system. If the guest is started on a large system, then migrated to a small system and back to the large system, the migration will be successful. The issue is that mfn_to_pfn() makes use of machine_to_phys_order, which is only configured once early in the boot process. After migration to a large host the mfns will exceed the order from the small system and a wrong code path is taken. Calling xen_setup_machphys_mapping() again in the resume path will avoid the crash. Signed-off-by: Olaf Hering --- arch/x86/xen/mmu.c | 2 +- arch/x86/xen/suspend.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) Index: linux-3.0-rc7/arch/x86/xen/mmu.c =================================================================== --- linux-3.0-rc7.orig/arch/x86/xen/mmu.c +++ linux-3.0-rc7/arch/x86/xen/mmu.c @@ -1623,7 +1623,7 @@ static void __init xen_map_identity_earl set_page_prot(pmd, PAGE_KERNEL_RO); } -void __init xen_setup_machphys_mapping(void) +void xen_setup_machphys_mapping(void) { struct xen_machphys_mapping mapping; unsigned long machine_to_phys_nr_ents; Index: linux-3.0-rc7/arch/x86/xen/suspend.c =================================================================== --- linux-3.0-rc7.orig/arch/x86/xen/suspend.c +++ linux-3.0-rc7/arch/x86/xen/suspend.c @@ -43,6 +43,8 @@ void xen_arch_hvm_post_suspend(int suspe void xen_arch_post_suspend(int suspend_cancelled) { + xen_setup_machphys_mapping(); + xen_build_mfn_list_list(); xen_setup_shared_info();