Index: xen-3.3.1-testing/xen/arch/x86/traps.c =================================================================== --- xen-3.3.1-testing.orig/xen/arch/x86/traps.c +++ xen-3.3.1-testing/xen/arch/x86/traps.c @@ -1266,6 +1266,7 @@ asmlinkage void do_early_page_fault(stru unsigned long *stk = (unsigned long *)regs; printk("Early fatal page fault at %04x:%p (cr2=%p, ec=%04x)\n", regs->cs, _p(regs->eip), _p(cr2), regs->error_code); + show_page_walk(cr2); printk("Stack dump: "); while ( ((long)stk & ((PAGE_SIZE - 1) & ~(BYTES_PER_LONG - 1))) != 0 ) printk("%p ", _p(*stk++)); Index: xen-3.3.1-testing/xen/arch/x86/x86_32/mm.c =================================================================== --- xen-3.3.1-testing.orig/xen/arch/x86/x86_32/mm.c +++ xen-3.3.1-testing/xen/arch/x86/x86_32/mm.c @@ -38,6 +38,7 @@ extern l1_pgentry_t l1_identmap[L1_PAGET unsigned int PAGE_HYPERVISOR = __PAGE_HYPERVISOR; unsigned int PAGE_HYPERVISOR_NOCACHE = __PAGE_HYPERVISOR_NOCACHE; +int mpt_valid; static unsigned long mpt_size; void *alloc_xen_pagetable(void) @@ -105,6 +106,8 @@ void __init paging_init(void) pg, (__PAGE_HYPERVISOR | _PAGE_PSE) & ~_PAGE_RW)); } + mpt_valid = 1; + /* Fill with an obvious debug pattern. */ for ( i = 0; i < (mpt_size / BYTES_PER_LONG); i++) set_gpfn_from_mfn(i, 0x55555555); Index: xen-3.3.1-testing/xen/arch/x86/x86_32/traps.c =================================================================== --- xen-3.3.1-testing.orig/xen/arch/x86/x86_32/traps.c +++ xen-3.3.1-testing/xen/arch/x86/x86_32/traps.c @@ -160,7 +160,8 @@ void show_page_walk(unsigned long addr) l3t += (cr3 & 0xFE0UL) >> 3; l3e = l3t[l3_table_offset(addr)]; mfn = l3e_get_pfn(l3e); - pfn = mfn_valid(mfn) ? get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; + pfn = mfn_valid(mfn) && mpt_valid ? + get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; printk(" L3[0x%03lx] = %"PRIpte" %08lx\n", l3_table_offset(addr), l3e_get_intpte(l3e), pfn); unmap_domain_page(l3t); @@ -170,7 +171,8 @@ void show_page_walk(unsigned long addr) l2t = map_domain_page(mfn); l2e = l2t[l2_table_offset(addr)]; mfn = l2e_get_pfn(l2e); - pfn = mfn_valid(mfn) ? get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; + pfn = mfn_valid(mfn) && mpt_valid ? + get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; printk(" L2[0x%03lx] = %"PRIpte" %08lx %s\n", l2_table_offset(addr), l2e_get_intpte(l2e), pfn, (l2e_get_flags(l2e) & _PAGE_PSE) ? "(PSE)" : ""); @@ -182,7 +184,8 @@ void show_page_walk(unsigned long addr) l1t = map_domain_page(mfn); l1e = l1t[l1_table_offset(addr)]; mfn = l1e_get_pfn(l1e); - pfn = mfn_valid(mfn) ? get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; + pfn = mfn_valid(mfn) && mpt_valid ? + get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; printk(" L1[0x%03lx] = %"PRIpte" %08lx\n", l1_table_offset(addr), l1e_get_intpte(l1e), pfn); unmap_domain_page(l1t); Index: xen-3.3.1-testing/xen/arch/x86/x86_64/mm.c =================================================================== --- xen-3.3.1-testing.orig/xen/arch/x86/x86_64/mm.c +++ xen-3.3.1-testing/xen/arch/x86/x86_64/mm.c @@ -33,6 +33,7 @@ #include #include +int mpt_valid; #ifdef CONFIG_COMPAT unsigned int m2p_compat_vstart = __HYPERVISOR_COMPAT_VIRT_START; #endif @@ -152,6 +153,8 @@ void __init paging_init(void) l2_ro_mpt++; } + mpt_valid = 1; + /* Create user-accessible L2 directory to map the MPT for compat guests. */ BUILD_BUG_ON(l4_table_offset(RDWR_MPT_VIRT_START) != l4_table_offset(HIRO_COMPAT_MPT_VIRT_START)); Index: xen-3.3.1-testing/xen/arch/x86/x86_64/traps.c =================================================================== --- xen-3.3.1-testing.orig/xen/arch/x86/x86_64/traps.c +++ xen-3.3.1-testing/xen/arch/x86/x86_64/traps.c @@ -174,7 +174,8 @@ void show_page_walk(unsigned long addr) l4t = mfn_to_virt(mfn); l4e = l4t[l4_table_offset(addr)]; mfn = l4e_get_pfn(l4e); - pfn = mfn_valid(mfn) ? get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; + pfn = mfn_valid(mfn) && mpt_valid ? + get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; printk(" L4[0x%03lx] = %"PRIpte" %016lx\n", l4_table_offset(addr), l4e_get_intpte(l4e), pfn); if ( !(l4e_get_flags(l4e) & _PAGE_PRESENT) ) @@ -183,7 +184,8 @@ void show_page_walk(unsigned long addr) l3t = mfn_to_virt(mfn); l3e = l3t[l3_table_offset(addr)]; mfn = l3e_get_pfn(l3e); - pfn = mfn_valid(mfn) ? get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; + pfn = mfn_valid(mfn) && mpt_valid ? + get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; printk(" L3[0x%03lx] = %"PRIpte" %016lx%s\n", l3_table_offset(addr), l3e_get_intpte(l3e), pfn, (l3e_get_flags(l3e) & _PAGE_PSE) ? " (PSE)" : ""); @@ -194,7 +196,8 @@ void show_page_walk(unsigned long addr) l2t = mfn_to_virt(mfn); l2e = l2t[l2_table_offset(addr)]; mfn = l2e_get_pfn(l2e); - pfn = mfn_valid(mfn) ? get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; + pfn = mfn_valid(mfn) && mpt_valid ? + get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; printk(" L2[0x%03lx] = %"PRIpte" %016lx %s\n", l2_table_offset(addr), l2e_get_intpte(l2e), pfn, (l2e_get_flags(l2e) & _PAGE_PSE) ? "(PSE)" : ""); @@ -205,7 +208,8 @@ void show_page_walk(unsigned long addr) l1t = mfn_to_virt(mfn); l1e = l1t[l1_table_offset(addr)]; mfn = l1e_get_pfn(l1e); - pfn = mfn_valid(mfn) ? get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; + pfn = mfn_valid(mfn) && mpt_valid ? + get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY; printk(" L1[0x%03lx] = %"PRIpte" %016lx\n", l1_table_offset(addr), l1e_get_intpte(l1e), pfn); } Index: xen-3.3.1-testing/xen/include/asm-x86/mm.h =================================================================== --- xen-3.3.1-testing.orig/xen/include/asm-x86/mm.h +++ xen-3.3.1-testing/xen/include/asm-x86/mm.h @@ -307,6 +307,7 @@ TYPE_SAFE(unsigned long,mfn); #define machine_to_phys_mapping ((unsigned long *)RDWR_MPT_VIRT_START) #define INVALID_M2P_ENTRY (~0UL) #define VALID_M2P(_e) (!((_e) & (1UL<<(BITS_PER_LONG-1)))) +extern int mpt_valid; #ifdef CONFIG_COMPAT #define compat_machine_to_phys_mapping ((unsigned int *)RDWR_COMPAT_MPT_VIRT_START)