X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_shadow_paging.c;h=142f41d3f0f4e7188007e63121c013c601374f90;hb=b527f44a71d32952d7b129a7ce5dbeb3969fb8d2;hp=70a2c77ad905a4b9aba6f7e82c7fe1fb5b8a7b63;hpb=eb87f60800c8634e37d1f8e71cd8f88605f2a46e;p=palacios.git diff --git a/palacios/src/palacios/vmm_shadow_paging.c b/palacios/src/palacios/vmm_shadow_paging.c index 70a2c77..142f41d 100644 --- a/palacios/src/palacios/vmm_shadow_paging.c +++ b/palacios/src/palacios/vmm_shadow_paging.c @@ -3,7 +3,7 @@ #include #include - +#include @@ -18,9 +18,24 @@ int init_shadow_page_state(struct shadow_page_state * state) { } int handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { - if (info->cpu_mode == PROTECTED_PG) { + + switch (info->cpu_mode) { + case PROTECTED_PG: return handle_shadow_pagefault32(info, fault_addr, error_code); - } else { + break; + case PROTECTED_PAE_PG: + case LONG_PG: + // currently not handled + return -1; + break; + case REAL: + case PROTECTED: + case PROTECTED_PAE: + case LONG: + // If paging is not turned on we need to handle the special cases + return handle_special_page_fault(info, fault_addr, error_code); + break; + default: return -1; } } @@ -47,13 +62,12 @@ int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_er guest_pde_access = can_access_pde32(guest_pde, fault_addr, error_code); if (guest_pde_access != PT_ACCESS_OK) { - - // // inject page fault to the guest (Guest PDE fault) - // - PrintDebug("Guest Page fault (currently not handled)\n"); - return -1; + info->ctrl_regs.cr2 = fault_addr; + raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code); + + return 0; } shadow_pde_access = can_access_pde32(shadow_pde, fault_addr, error_code); @@ -84,6 +98,7 @@ int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_er } else { /* * Check the Intel manual because we are ignoring Large Page issues here + * Also be wary of hooked pages */ } @@ -107,11 +122,15 @@ int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_er pte32_t * shadow_pte = (pte32_t *)PDE32_T_ADDR((*shadow_pde_entry)); pte32_t * guest_pte = NULL; - // Page Table entry fault + // Page Table Entry fault if (guest_pa_to_host_va(info, PDE32_T_ADDR((*guest_pde_entry)), (addr_t*)&guest_pte) == -1) { PrintDebug("Invalid Guest PTE Address: 0x%x\n", PDE32_T_ADDR((*guest_pde_entry))); - return -1; + // Machine check the guest + + raise_exception(info, MC_EXCEPTION); + + return 0; } @@ -121,7 +140,14 @@ int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_er } } else { - PrintDebug("Unknown Error\n"); + // Unknown error raise page fault in guest + info->ctrl_regs.cr2 = fault_addr; + raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code); + + // For debugging we will return an error here for the time being, + // this probably shouldn't ever happen + PrintDebug("Unknown Error occurred\n"); + PrintDebug("Manual Says to inject page fault into guest\n"); return -1; } @@ -135,7 +161,7 @@ int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_er /* * We assume the the guest pte pointer has already been translated to a host virtual address */ -int handle_shadow_pte32_fault(struct guest_info* info, +int handle_shadow_pte32_fault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code, pte32_t * shadow_pte, @@ -150,80 +176,86 @@ int handle_shadow_pte32_fault(struct guest_info* info, // Check the guest page permissions guest_pte_access = can_access_pte32(guest_pte, fault_addr, error_code); + if (guest_pte_access != PT_ACCESS_OK) { - - // - // Inject page fault into the guest - // - - PrintDebug("Guest Page fault (currently not handled)\n"); - return -1; + // Inject page fault into the guest + + info->ctrl_regs.cr2 = fault_addr; + raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code); + + return 0; } - + + shadow_pte_access = can_access_pte32(shadow_pte, fault_addr, error_code); - if (shadow_pte_access == PT_ENTRY_NOT_PRESENT) { + if (shadow_pte_access == PT_ACCESS_OK) { + // Inconsistent state... + // Guest Re-Entry will flush page tables and everything should now work + return 0; + } else if (shadow_pte_access == PT_ENTRY_NOT_PRESENT) { addr_t shadow_pa; addr_t guest_pa = PTE32_T_ADDR((*guest_pte_entry)); // Page Table Entry Not Present - if (get_shadow_addr_type(info, guest_pa) == HOST_REGION_INVALID) { + host_region_type_t host_page_type = get_shadow_addr_type(info, guest_pa); - // + if (host_page_type == HOST_REGION_INVALID) { // Inject a machine check in the guest - // - - PrintDebug("Invalid Guest Address in page table (0x%x)\n", guest_pa); - return -1; - } - - shadow_pa = get_shadow_addr(info, guest_pa); - shadow_pte_entry->page_base_addr = PT32_BASE_ADDR(shadow_pa); + raise_exception(info, MC_EXCEPTION); - shadow_pte_entry->present = guest_pte_entry->present; - shadow_pte_entry->user_page = guest_pte_entry->user_page; - - //set according to VMM policy - shadow_pte_entry->write_through = 0; - shadow_pte_entry->cache_disable = 0; - shadow_pte_entry->global_page = 0; - // - - guest_pte_entry->accessed = 1; - - if (guest_pte_entry->dirty == 1) { - shadow_pte_entry->writable = guest_pte_entry->writable; - } else if ((guest_pte_entry->dirty == 0) && (error_code.write == 1)) { - shadow_pte_entry->writable = guest_pte_entry->writable; - guest_pte_entry->dirty = 1; - } else if ((guest_pte_entry->dirty = 0) && (error_code.write == 0)) { - shadow_pte_entry->writable = 0; + PrintDebug("Invalid Guest Address in page table (0x%x)\n", guest_pa); + return 0; + + } else if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) { + + shadow_pa = get_shadow_addr(info, guest_pa); + + shadow_pte_entry->page_base_addr = PT32_BASE_ADDR(shadow_pa); + + shadow_pte_entry->present = guest_pte_entry->present; + shadow_pte_entry->user_page = guest_pte_entry->user_page; + + //set according to VMM policy + shadow_pte_entry->write_through = 0; + shadow_pte_entry->cache_disable = 0; + shadow_pte_entry->global_page = 0; + // + + guest_pte_entry->accessed = 1; + + if (guest_pte_entry->dirty == 1) { + shadow_pte_entry->writable = guest_pte_entry->writable; + } else if ((guest_pte_entry->dirty == 0) && (error_code.write == 1)) { + shadow_pte_entry->writable = guest_pte_entry->writable; + guest_pte_entry->dirty = 1; + } else if ((guest_pte_entry->dirty = 0) && (error_code.write == 0)) { + shadow_pte_entry->writable = 0; + } + } else { + // Page fault handled by hook functions + if (handle_special_page_fault(info, fault_addr, error_code) == -1) { + PrintDebug("Special Page fault handler returned error for address: %x\n", fault_addr); + return -1; + } } - } else if (shadow_pte_access == PT_WRITE_ERROR) { - - // - // Page Table Entry marked read-only - // - - PrintDebug("Shadow Paging Write Error\n"); - return -1; - } else if (shadow_pte_access == PT_USER_ERROR) { - - // - // Page Table Entry marked non-user - // - - PrintDebug("Shadow Paging User access error\n"); - return -1; - } else if (shadow_pte_access == PT_ACCESS_OK) { + } else if ((shadow_pte_access == PT_WRITE_ERROR) && + (guest_pte_entry->dirty == 0)) { + guest_pte_entry->dirty = 1; + shadow_pte_entry->writable = guest_pte_entry->writable; - PrintDebug("Page Fault occurred for No Reason\n"); - return -1; + return 0; } else { - PrintDebug("Unknown Error\n"); + // Inject page fault into the guest + + info->ctrl_regs.cr2 = fault_addr; + raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code); + + PrintDebug("PTE Page fault fell through... Not sure if this should ever happen\n"); + PrintDebug("Manual Says to inject page fault into guest\n"); return -1; } @@ -243,7 +275,75 @@ addr_t create_new_shadow_pt32(struct guest_info * info) { +/* Currently Does not work with Segmentation!!! */ +int handle_shadow_invlpg(struct guest_info * info) { + if (info->cpu_mode == PROTECTED_PG) { + char instr[15]; + int ret; + int index = 0; + ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr); + if (ret != 15) { + PrintDebug("Could not read instruction 0x%x (ret=%d)\n", info->rip, ret); + return -1; + } + + + /* Can INVLPG work with Segments?? */ + while (is_prefix_byte(instr[index])) { + index++; + } + + + if ((instr[index] == (uchar_t)0x0f) && + (instr[index + 1] == (uchar_t)0x01)) { + + addr_t first_operand; + addr_t second_operand; + operand_type_t addr_type; + + index += 2; + + addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32); + + if (addr_type == MEM_OPERAND) { + pde32_t * shadow_pd = (pde32_t *)CR3_TO_PDE32(info->shdw_pg_state.shadow_cr3); + pde32_t * shadow_pde_entry = (pde32_t *)&shadow_pd[PDE32_INDEX(first_operand)]; + + //PrintDebug("PDE Index=%d\n", PDE32_INDEX(first_operand)); + //PrintDebug("FirstOperand = %x\n", first_operand); + + if (shadow_pde_entry->large_page == 1) { + shadow_pde_entry->present = 0; + } else { + if (shadow_pde_entry->present == 1) { + pte32_t * shadow_pt = (pte32_t *)PDE32_T_ADDR((*shadow_pde_entry)); + pte32_t * shadow_pte_entry = (pte32_t *)&shadow_pt[PTE32_INDEX(first_operand)]; + + shadow_pte_entry->present = 0; + } + } + + info->rip += index; + + } else { + PrintDebug("Invalid Operand type\n"); + return -1; + } + } else { + PrintDebug("invalid Instruction Opcode\n"); + PrintTraceMemDump(instr, 15); + return -1; + } + } + + return 0; +} + + + +/* Deprecated */ +/* addr_t setup_shadow_pt32(struct guest_info * info, addr_t virt_cr3) { addr_t cr3_guest_addr = CR3_TO_PDE32(virt_cr3); pde32_t * guest_pde; @@ -320,4 +420,4 @@ addr_t setup_shadow_pte32(struct guest_info * info, addr_t pt_host_addr) { return (addr_t)host_pte; } - +*/