///////////////////////////////////////////////////////////////////////// // $Id: paging.cc,v 1.226 2010-10-07 16:39:31 sshwarts Exp $ ///////////////////////////////////////////////////////////////////////// // // Copyright (C) 2001-2010 The Bochs Project // // This library is free software; you can redistribute it and/or // modify it under the terms of the GNU Lesser General Public // License as published by the Free Software Foundation; either // version 2 of the License, or (at your option) any later version. // // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // Lesser General Public License for more details. // // You should have received a copy of the GNU Lesser General Public // License along with this library; if not, write to the Free Software // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA B 02110-1301 USA ///////////////////////////////////////////////////////////////////////// #define NEED_CPU_REG_SHORTCUTS 1 #include "bochs.h" #include "cpu.h" #define LOG_THIS BX_CPU_THIS_PTR // X86 Registers Which Affect Paging: // ================================== // // CR0: // bit 31: PG, Paging (386+) // bit 16: WP, Write Protect (486+) // 0: allow supervisor level writes into user level RO pages // 1: inhibit supervisor level writes into user level RO pages // // CR3: // bit 31..12: PDBR, Page Directory Base Register (386+) // bit 4: PCD, Page level Cache Disable (486+) // Controls caching of current page directory. Affects only the processor's // internal caches (L1 and L2). // This flag ignored if paging disabled (PG=0) or cache disabled (CD=1). // Values: // 0: Page Directory can be cached // 1: Page Directory not cached // bit 3: PWT, Page level Writes Transparent (486+) // Controls write-through or write-back caching policy of current page // directory. Affects only the processor's internal caches (L1 and L2). // This flag ignored if paging disabled (PG=0) or cache disabled (CD=1). // Values: // 0: write-back caching enabled // 1: write-through caching enabled // // CR4: // bit 4: PSE, Page Size Extension (Pentium+) // 0: 4KByte pages (typical) // 1: 4MByte or 2MByte pages // bit 5: PAE, Physical Address Extension (Pentium Pro+) // 0: 32bit physical addresses // 1: 36bit physical addresses // bit 7: PGE, Page Global Enable (Pentium Pro+) // The global page feature allows frequently used or shared pages // to be marked as global (PDE or PTE bit 8). Global pages are // not flushed from TLB on a task switch or write to CR3. // Values: // 0: disables global page feature // 1: enables global page feature // // page size extention and physical address size extention matrix (legacy mode) // ============================================================================== // CR0.PG CR4.PAE CR4.PSE PDPE.PS PDE.PS | page size physical address size // ============================================================================== // 0 X X R X | -- paging disabled // 1 0 0 R X | 4K 32bits // 1 0 1 R 0 | 4K 32bits // 1 0 1 R 1 | 4M 32bits // 1 1 X R 0 | 4K 36bits // 1 1 X R 1 | 2M 36bits // page size extention and physical address size extention matrix (long mode) // ============================================================================== // CR0.PG CR4.PAE CR4.PSE PDPE.PS PDE.PS | page size physical address size // ============================================================================== // 1 1 X 0 0 | 4K 52bits // 1 1 X 0 1 | 2M 52bits // 1 1 X 1 - | 1G 52bits // Page Directory/Table Entry Fields Defined: // ========================================== // NX: No Execute // This bit controls the ability to execute code from all physical // pages mapped by the table entry. // 0: Code can be executed from the mapped physical pages // 1: Code cannot be executed // The NX bit can only be set when the no-execute page-protection // feature is enabled by setting EFER.NXE=1, If EFER.NXE=0, the // NX bit is treated as reserved. In this case, #PF occurs if the // NX bit is not cleared to zero. // // G: Global flag // Indiciates a global page when set. When a page is marked // global and the PGE flag in CR4 is set, the page table or // directory entry for the page is not invalidated in the TLB // when CR3 is loaded or a task switch occurs. Only software // clears and sets this flag. For page directory entries that // point to page tables, this flag is ignored and the global // characteristics of a page are set in the page table entries. // // PS: Page Size flag // Only used in page directory entries. When PS=0, the page // size is 4KBytes and the page directory entry points to a // page table. When PS=1, the page size is 4MBytes for // normal 32-bit addressing and 2MBytes if extended physical // addressing. // // PAT: Page-Attribute Table // This bit is only present in the lowest level of the page // translation hierarchy. The PAT bit is the high-order bit // of a 3-bit index into the PAT register. The other two // bits involved in forming the index are the PCD and PWT // bits. // // D: Dirty bit: // Processor sets the Dirty bit in the 2nd-level page table before a // write operation to an address mapped by that page table entry. // Dirty bit in directory entries is undefined. // // A: Accessed bit: // Processor sets the Accessed bits in both levels of page tables before // a read/write operation to a page. // // PCD: Page level Cache Disable // Controls caching of individual pages or page tables. // This allows a per-page based mechanism to disable caching, for // those pages which contained memory mapped IO, or otherwise // should not be cached. Processor ignores this flag if paging // is not used (CR0.PG=0) or the cache disable bit is set (CR0.CD=1). // Values: // 0: page or page table can be cached // 1: page or page table is not cached (prevented) // // PWT: Page level Write Through // Controls the write-through or write-back caching policy of individual // pages or page tables. Processor ignores this flag if paging // is not used (CR0.PG=0) or the cache disable bit is set (CR0.CD=1). // Values: // 0: write-back caching // 1: write-through caching // // U/S: User/Supervisor level // 0: Supervisor level - for the OS, drivers, etc. // 1: User level - application code and data // // R/W: Read/Write access // 0: read-only access // 1: read/write access // // P: Present // 0: Not present // 1: Present // ========================================== // Combined page directory/page table protection: // ============================================== // There is one column for the combined effect on a 386 // and one column for the combined effect on a 486+ CPU. // // +----------------+-----------------+----------------+----------------+ // | Page Directory| Page Table | Combined 386 | Combined 486+ | // |Privilege Type | Privilege Type | Privilege Type| Privilege Type| // |----------------+-----------------+----------------+----------------| // |User R | User R | User R | User R | // |User R | User RW | User R | User R | // |User RW | User R | User R | User R | // |User RW | User RW | User RW | User RW | // |User R | Supervisor R | User R | Supervisor RW | // |User R | Supervisor RW | User R | Supervisor RW | // |User RW | Supervisor R | User R | Supervisor RW | // |User RW | Supervisor RW | User RW | Supervisor RW | // |Supervisor R | User R | User R | Supervisor RW | // |Supervisor R | User RW | User R | Supervisor RW | // |Supervisor RW | User R | User R | Supervisor RW | // |Supervisor RW | User RW | User RW | Supervisor RW | // |Supervisor R | Supervisor R | Supervisor RW | Supervisor RW | // |Supervisor R | Supervisor RW | Supervisor RW | Supervisor RW | // |Supervisor RW | Supervisor R | Supervisor RW | Supervisor RW | // |Supervisor RW | Supervisor RW | Supervisor RW | Supervisor RW | // +----------------+-----------------+----------------+----------------+ // Page Fault Error Code Format: // ============================= // // bits 31..4: Reserved // bit 3: RSVD (Pentium Pro+) // 0: fault caused by reserved bits set to 1 in a page directory // when the PSE or PAE flags in CR4 are set to 1 // 1: fault was not caused by reserved bit violation // bit 2: U/S (386+) // 0: fault originated when in supervior mode // 1: fault originated when in user mode // bit 1: R/W (386+) // 0: access causing the fault was a read // 1: access causing the fault was a write // bit 0: P (386+) // 0: fault caused by a nonpresent page // 1: fault caused by a page level protection violation // Some paging related notes: // ========================== // // - When the processor is running in supervisor level, all pages are both // readable and writable (write-protect ignored). When running at user // level, only pages which belong to the user level are accessible; // read/write & read-only are readable, read/write are writable. // // - If the Present bit is 0 in either level of page table, an // access which uses these entries will generate a page fault. // // - (A)ccess bit is used to report read or write access to a page // or 2nd level page table. // // - (D)irty bit is used to report write access to a page. // // - Processor running at CPL=0,1,2 maps to U/S=0 // Processor running at CPL=3 maps to U/S=1 #if BX_SUPPORT_X86_64 #define BX_INVALID_TLB_ENTRY BX_CONST64(0xffffffffffffffff) #else #define BX_INVALID_TLB_ENTRY 0xffffffff #endif // bit [11] of the TLB lpf used for TLB_HostPtr valid indication #define TLB_LPFOf(laddr) AlignedAccessLPFOf(laddr, 0x7ff) #if BX_CPU_LEVEL >= 4 # define BX_PRIV_CHECK_SIZE 32 #else # define BX_PRIV_CHECK_SIZE 16 #endif // The 'priv_check' array is used to decide if the current access // has the proper paging permissions. An index is formed, based // on parameters such as the access type and level, the write protect // flag and values cached in the TLB. The format of the index into this // array is: // // |4 |3 |2 |1 |0 | // |wp|us|us|rw|rw| // | | | | | // | | | | +---> r/w of current access // | | +--+------> u/s,r/w combined of page dir & table (cached) // | +------------> u/s of current access // +---------------> Current CR0.WP value /* 0xff0bbb0b */ static const Bit8u priv_check[BX_PRIV_CHECK_SIZE] = { 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, #if BX_CPU_LEVEL >= 4 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1 #endif }; #define BX_PAGING_PHY_ADDRESS_RESERVED_BITS \ (BX_PHY_ADDRESS_RESERVED_BITS & BX_CONST64(0xfffffffffffff)) #define PAGE_DIRECTORY_NX_BIT (BX_CONST64(0x8000000000000000)) #define BX_CR3_PAGING_MASK (BX_CONST64(0x000ffffffffff000)) #define BX_CR3_LEGACY_PAE_PAGING_MASK (0xffffffe0) // Each entry in the TLB cache has 3 entries: // // lpf: Linear Page Frame (page aligned linear address of page) // bits 32..12 Linear page frame // bit 11 0: TLB HostPtr access allowed, 1: not allowed // bit 10...0 Invalidate index // // ppf: Physical Page Frame (page aligned phy address of page) // // hostPageAddr: // Host Page Frame address used for direct access to // the mem.vector[] space allocated for the guest physical // memory. If this is zero, it means that a pointer // to the host space could not be generated, likely because // that page of memory is not standard memory (it might // be memory mapped IO, ROM, etc). // // accessBits: // // bit 31: Page is a global page. // // The following bits are used for a very efficient permissions // check. The goal is to be able, using only the current privilege // level and access type, to determine if the page tables allow the // access to occur or at least should rewalk the page tables. On // the first read access, permissions are set to only read, so a // rewalk is necessary when a subsequent write fails the tests. // This allows for the dirty bit to be set properly, but for the // test to be efficient. Note that the CR0.WP flag is not present. // The values in the following flags is based on the current CR0.WP // value, necessitating a TLB flush when CR0.WP changes. // // The test is: // OK = (accessBits & ((E<<2) | (W<<1) | U)) <> 0 // // where E:1=Execute, 0=Data; // W:1=Write, 0=Read; // U:1=CPL3, 0=CPL0-2 // // Thus for reads, it is: // OK = ( U ) // for writes: // OK = 0x2 | ( U ) // and for code fetches: // OK = 0x4 | ( U ) // // Note, that the TLB should have TLB_HostPtr bit set when direct // access through host pointer is NOT allowed for the page. A memory // operation asking for a direct access through host pointer will // set TLB_HostPtr bit in its lpf field and thus get TLB miss result // when the direct access is not allowed. // #define TLB_HostPtr (0x800) /* set this bit when direct access is NOT allowed */ #define TLB_GlobalPage (0x80000000) #define TLB_SysOnly (0x1) #define TLB_ReadOnly (0x2) #define TLB_NoExecute (0x4) // === TLB Instrumentation section ============================== // Note: this is an approximation of what Peter Tattam had. #define InstrumentTLB 0 #if InstrumentTLB static unsigned tlbLookups=0; static unsigned tlbMisses=0; static unsigned tlbGlobalFlushes=0; static unsigned tlbNonGlobalFlushes=0; #define InstrTLB_StatsMask 0xfffff #define InstrTLB_Stats() {\ if ((tlbLookups & InstrTLB_StatsMask) == 0) { \ BX_INFO(("TLB lookup:%8d miss:%8d %6.2f%% flush:%8d %6.2f%%", \ tlbLookups, \ tlbMisses, \ tlbMisses * 100.0 / tlbLookups, \ (tlbGlobalFlushes+tlbNonGlobalFlushes), \ (tlbGlobalFlushes+tlbNonGlobalFlushes) * 100.0 / tlbLookups \ )); \ tlbLookups = tlbMisses = tlbGlobalFlushes = tlbNonGlobalFlushes = 0; \ } \ } #define InstrTLB_Increment(v) (v)++ #else #define InstrTLB_Stats() #define InstrTLB_Increment(v) #endif // ============================================================== void BX_CPU_C::TLB_flush(void) { #if InstrumentTLB InstrTLB_Increment(tlbGlobalFlushes); #endif invalidate_prefetch_q(); for (unsigned n=0; n= 5 BX_CPU_THIS_PTR TLB.split_large = 0; // flush whole TLB #endif #if BX_SUPPORT_MONITOR_MWAIT // invalidating of the TLB might change translation for monitored page // and cause subsequent MWAIT instruction to wait forever BX_CPU_THIS_PTR monitor.reset_monitor(); #endif } #if BX_CPU_LEVEL >= 6 void BX_CPU_C::TLB_flushNonGlobal(void) { #if InstrumentTLB InstrTLB_Increment(tlbNonGlobalFlushes); #endif invalidate_prefetch_q(); BX_CPU_THIS_PTR TLB.split_large = 0; for (unsigned n=0; naccessBits & TLB_GlobalPage)) { tlbEntry->lpf = BX_INVALID_TLB_ENTRY; } else { if (tlbEntry->lpf_mask > 0xfff) BX_CPU_THIS_PTR TLB.split_large = 1; } } #if BX_SUPPORT_MONITOR_MWAIT // invalidating of the TLB might change translation for monitored page // and cause subsequent MWAIT instruction to wait forever BX_CPU_THIS_PTR monitor.reset_monitor(); #endif } #endif void BX_CPU_C::TLB_invlpg(bx_address laddr) { invalidate_prefetch_q(); BX_DEBUG(("TLB_invlpg(0x"FMT_ADDRX"): invalidate TLB entry", laddr)); #if BX_CPU_LEVEL >= 5 bx_bool large = 0; if (BX_CPU_THIS_PTR TLB.split_large) { // make sure INVLPG handles correctly large pages for (unsigned n=0; nlpf_mask; if ((laddr & ~lpf_mask) == (tlbEntry->lpf & ~lpf_mask)) { tlbEntry->lpf = BX_INVALID_TLB_ENTRY; } else { if (lpf_mask > 0xfff) large = 1; } } BX_CPU_THIS_PTR TLB.split_large = large; } else #endif { unsigned TLB_index = BX_TLB_INDEX_OF(laddr, 0); bx_address lpf = LPFOf(laddr); bx_TLB_entry *tlbEntry = &BX_CPU_THIS_PTR TLB.entry[TLB_index]; if (TLB_LPFOf(tlbEntry->lpf) == lpf) { tlbEntry->lpf = BX_INVALID_TLB_ENTRY; } } #if BX_SUPPORT_MONITOR_MWAIT // invalidating of the TLB entry might change translation for monitored // page and cause subsequent MWAIT instruction to wait forever BX_CPU_THIS_PTR monitor.reset_monitor(); #endif } void BX_CPP_AttrRegparmN(1) BX_CPU_C::INVLPG(bxInstruction_c* i) { if (!real_mode() && CPL!=0) { BX_ERROR(("INVLPG: priveledge check failed, generate #GP(0)")); exception(BX_GP_EXCEPTION, 0); } bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); bx_address laddr = get_laddr(i->seg(), eaddr); #if BX_SUPPORT_VMX VMexit_INVLPG(i, laddr); #endif #if BX_SUPPORT_X86_64 if (! IsCanonical(laddr)) { BX_ERROR(("INVLPG: non-canonical access !")); exception(int_number(i->seg()), 0); } #endif BX_INSTR_TLB_CNTRL(BX_CPU_ID, BX_INSTR_INVLPG, laddr); TLB_invlpg(laddr); } // error checking order - page not present, reserved bits, protection #define ERROR_NOT_PRESENT 0x00 #define ERROR_PROTECTION 0x01 #define ERROR_RESERVED 0x08 #define ERROR_CODE_ACCESS 0x10 void BX_CPU_C::page_fault(unsigned fault, bx_address laddr, unsigned user, unsigned rw) { unsigned error_code = fault; unsigned isWrite = rw & 1; error_code |= (user << 2) | (isWrite << 1); #if BX_SUPPORT_X86_64 if (BX_CPU_THIS_PTR cr4.get_PAE() && BX_CPU_THIS_PTR efer.get_NXE() && rw == BX_EXECUTE) error_code |= ERROR_CODE_ACCESS; // I/D = 1 #endif #if BX_SUPPORT_VMX VMexit_Event(0, BX_HARDWARE_EXCEPTION, BX_PF_EXCEPTION, error_code, 1, laddr); // before the CR2 was modified #endif BX_CPU_THIS_PTR cr2 = laddr; #if BX_SUPPORT_X86_64 BX_DEBUG(("page fault for address %08x%08x @ %08x%08x", GET32H(laddr), GET32L(laddr), GET32H(RIP), GET32L(RIP))); #else BX_DEBUG(("page fault for address %08x @ %08x", laddr, EIP)); #endif exception(BX_PF_EXCEPTION, error_code); } #define BX_LEVEL_PML4 3 #define BX_LEVEL_PDPE 2 #define BX_LEVEL_PDE 1 #define BX_LEVEL_PTE 0 static const char *bx_paging_level[4] = { "PTE", "PDE", "PDPE", "PML4" }; #if BX_CPU_LEVEL >= 6 int BX_CPU_C::check_entry_PAE(const char *s, Bit64u entry, Bit64u reserved, unsigned rw, bx_bool *nx_fault) { if (!(entry & 0x1)) { BX_DEBUG(("%s: entry not present", s)); return ERROR_NOT_PRESENT; } if (entry & reserved) { BX_DEBUG(("%s: reserved bit is set %08x:%08x", s, GET32H(entry), GET32L(entry))); return ERROR_RESERVED | ERROR_PROTECTION; } #if BX_SUPPORT_X86_64 if (! long_mode()) { if (entry & BX_CONST64(0x7ff0000000000000)) { BX_DEBUG(("%s: reserved bit is set %08x:%08x", s, GET32H(entry), GET32L(entry))); return ERROR_RESERVED | ERROR_PROTECTION; } } if (entry & PAGE_DIRECTORY_NX_BIT) { if (! BX_CPU_THIS_PTR efer.get_NXE()) { BX_DEBUG(("%s: NX bit set when EFER.NXE is disabled", s)); return ERROR_RESERVED | ERROR_PROTECTION; } if (rw == BX_EXECUTE) { BX_DEBUG(("%s: non-executable page fault occured", s)); *nx_fault = 1; } } #endif return -1; } // Format of a Long Mode Non-Leaf Entry // ----------------------------------------------------------- // 00 | Present (P) // 01 | R/W // 02 | U/S // 03 | Page-Level Write-Through (PWT) // 04 | Page-Level Cache-Disable (PCD) // 05 | Accessed (A) // 06 | (ignored) // 07 | Page Size (PS), must be 0 if no Large Page on the level // 11-08 | (ignored) // PA-12 | Physical address of 4-KByte aligned page-directory-pointer table // 51-PA | Reserved (must be zero) // 62-52 | (ignored) // 63 | Execute-Disable (XD) (if EFER.NXE=1, reserved otherwise) // ----------------------------------------------------------- #define PAGING_PAE_RESERVED_BITS (BX_PAGING_PHY_ADDRESS_RESERVED_BITS) // Format of a PDPTE that References a 1-GByte Page // ----------------------------------------------------------- // 00 | Present (P) // 01 | R/W // 02 | U/S // 03 | Page-Level Write-Through (PWT) // 04 | Page-Level Cache-Disable (PCD) // 05 | Accessed (A) // 06 | (ignored) // 07 | Page Size, must be 1 to indicate a 1-GByte Page // 08 | Global (G) (if CR4.PGE=1, ignored otherwise) // 11-09 | (ignored) // 12 | PAT (if PAT is supported, reserved otherwise) // 29-13 | Reserved (must be zero) // PA-30 | Physical address of the 1-Gbyte Page // 51-PA | Reserved (must be zero) // 62-52 | (ignored) // 63 | Execute-Disable (XD) (if EFER.NXE=1, reserved otherwise) // ----------------------------------------------------------- #define PAGING_PAE_PDPTE1G_RESERVED_BITS \ (BX_PAGING_PHY_ADDRESS_RESERVED_BITS | BX_CONST64(0x3FFFE000)) // Format of a PAE PDE that Maps a 2-MByte Page // ----------------------------------------------------------- // 00 | Present (P) // 01 | R/W // 02 | U/S // 03 | Page-Level Write-Through (PWT) // 04 | Page-Level Cache-Disable (PCD) // 05 | Accessed (A) // 06 | Dirty (D) // 07 | Page Size (PS), must be 1 to indicate a 2-MByte Page // 08 | Global (G) (if CR4.PGE=1, ignored otherwise) // 11-09 | (ignored) // 12 | PAT (if PAT is supported, reserved otherwise) // 20-13 | Reserved (must be zero) // PA-21 | Physical address of the 2-MByte page // 51-PA | Reserved (must be zero) // 62-52 | ignored in long mode, reserved (must be 0) in legacy PAE mode // 63 | Execute-Disable (XD) (if EFER.NXE=1, reserved otherwise) // ----------------------------------------------------------- #define PAGING_PAE_PDE2M_RESERVED_BITS \ (BX_PAGING_PHY_ADDRESS_RESERVED_BITS | BX_CONST64(0x001FE000)) // Format of a PAE PTE that Maps a 4-KByte Page // ----------------------------------------------------------- // 00 | Present (P) // 01 | R/W // 02 | U/S // 03 | Page-Level Write-Through (PWT) // 04 | Page-Level Cache-Disable (PCD) // 05 | Accessed (A) // 06 | Dirty (D) // 07 | PAT (if PAT is supported, reserved otherwise) // 08 | Global (G) (if CR4.PGE=1, ignored otherwise) // 11-09 | (ignored) // PA-12 | Physical address of the 4-KByte page // 51-PA | Reserved (must be zero) // 62-52 | ignored in long mode, reserved (must be 0) in legacy PAE mode // 63 | Execute-Disable (XD) (if EFER.NXE=1, reserved otherwise) // ----------------------------------------------------------- #if BX_SUPPORT_X86_64 // Translate a linear address to a physical address in long mode bx_phy_address BX_CPU_C::translate_linear_long_mode(bx_address laddr, Bit32u &lpf_mask, Bit32u &combined_access, unsigned curr_pl, unsigned rw) { bx_phy_address entry_addr[4]; bx_phy_address ppf = BX_CPU_THIS_PTR cr3 & BX_CR3_PAGING_MASK; Bit64u entry[4]; bx_bool nx_fault = 0; unsigned pl = (curr_pl == 3); int leaf = BX_LEVEL_PTE; combined_access = 0x06; for (leaf = BX_LEVEL_PML4;; --leaf) { entry_addr[leaf] = ppf + ((laddr >> (9 + 9*leaf)) & 0xff8); #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) entry_addr[leaf] = translate_guest_physical(entry_addr[leaf], laddr, 1, 1, rw); } #endif access_read_physical(entry_addr[leaf], 8, &entry[leaf]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[leaf], 8, (BX_PTE_ACCESS + (leaf<<4)) | BX_READ, (Bit8u*)(&entry[leaf])); Bit64u curr_entry = entry[leaf]; int fault = check_entry_PAE(bx_paging_level[leaf], curr_entry, PAGING_PAE_RESERVED_BITS, rw, &nx_fault); if (fault >= 0) page_fault(fault, laddr, pl, rw); combined_access &= curr_entry & 0x06; // U/S and R/W ppf = curr_entry & BX_CONST64(0x000ffffffffff000); if (leaf == BX_LEVEL_PTE) break; if (curr_entry & 0x80) { if (leaf > (BX_LEVEL_PDE + !!bx_cpuid_support_1g_paging())) { BX_DEBUG(("%s: PS bit set !")); page_fault(ERROR_RESERVED | ERROR_PROTECTION, laddr, pl, rw); } if (leaf == BX_LEVEL_PDPE) { if (curr_entry & PAGING_PAE_PDPTE1G_RESERVED_BITS) { BX_DEBUG(("PAE PDPE1G: reserved bit is set: PDPE=%08x:%08x", GET32H(curr_entry), GET32L(curr_entry))); page_fault(ERROR_RESERVED | ERROR_PROTECTION, laddr, pl, rw); } // Make up the physical page frame address. ppf = (bx_phy_address)((curr_entry & BX_CONST64(0x000fffffc0000000)) | (laddr & 0x3ffff000)); lpf_mask = 0x3fffffff; break; } if (leaf == BX_LEVEL_PDE) { if (curr_entry & PAGING_PAE_PDE2M_RESERVED_BITS) { BX_DEBUG(("PAE PDE2M: reserved bit is set PDE=%08x:%08x", GET32H(curr_entry), GET32L(curr_entry))); page_fault(ERROR_RESERVED | ERROR_PROTECTION, laddr, pl, rw); } // Make up the physical page frame address. ppf = (bx_phy_address)((curr_entry & BX_CONST64(0x000fffffffe00000)) | (laddr & 0x001ff000)); lpf_mask = 0x1fffff; break; } } } bx_bool isWrite = (rw & 1); // write or r-m-w unsigned priv_index = (BX_CPU_THIS_PTR cr0.get_WP() << 4) | // bit 4 (pl<<3) | // bit 3 (combined_access | isWrite); // bit 2,1,0 if (!priv_check[priv_index] || nx_fault) page_fault(ERROR_PROTECTION, laddr, pl, rw); if (BX_CPU_THIS_PTR cr4.get_PGE()) combined_access |= (entry[leaf] & 0x100); // G // Update A bit if needed. for (int level=BX_LEVEL_PML4; level > leaf; level--) { if (!(entry[level] & 0x20)) { entry[level] |= 0x20; access_write_physical(entry_addr[level], 8, &entry[level]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[level], 8, (BX_PTE_ACCESS + (level<<4)) | BX_WRITE, (Bit8u*)(&entry[level])); } } // Update A/D bits if needed. if (!(entry[leaf] & 0x20) || (isWrite && !(entry[leaf] & 0x40))) { entry[leaf] |= (0x20 | (isWrite<<6)); // Update A and possibly D bits access_write_physical(entry_addr[leaf], 8, &entry[leaf]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[leaf], 8, (BX_PTE_ACCESS + (leaf<<4)) | BX_WRITE, (Bit8u*)(&entry[leaf])); } return ppf; } #endif // Format of Legacy PAE PDPTR entry (PDPTE) // ----------------------------------------------------------- // 00 | Present (P) // 02-01 | Reserved (must be zero) // 03 | Page-Level Write-Through (PWT) (486+), 0=reserved otherwise // 04 | Page-Level Cache-Disable (PCD) (486+), 0=reserved otherwise // 08-05 | Reserved (must be zero) // 11-09 | (ignored) // PA-12 | Physical address of 4-KByte aligned page directory // 63-PA | Reserved (must be zero) // ----------------------------------------------------------- #define PAGING_PAE_PDPTE_RESERVED_BITS \ (BX_PAGING_PHY_ADDRESS_RESERVED_BITS | BX_CONST64(0xFFF00000000001E6)) bx_bool BX_CPP_AttrRegparmN(1) BX_CPU_C::CheckPDPTR(bx_phy_address cr3_val) { cr3_val &= 0xffffffe0; #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) cr3_val = translate_guest_physical(cr3_val, 0, 0, 0, BX_READ); } #endif Bit64u pdptr[4]; int n; for (n=0; n<4; n++) { // read and check PDPTE entries bx_phy_address pdpe_entry_addr = (bx_phy_address) (cr3_val | (n << 3)); access_read_physical(pdpe_entry_addr, 8, &(pdptr[n])); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, pdpe_entry_addr, 8, (BX_PDPTR0_ACCESS + (n<<4)) | BX_READ, (Bit8u*) &(pdptr[n])); if (pdptr[n] & 0x1) { if (pdptr[n] & PAGING_PAE_PDPTE_RESERVED_BITS) return 0; } } // load new PDPTRs for (n=0; n<4; n++) BX_CPU_THIS_PTR PDPTR_CACHE.entry[n] = pdptr[n]; BX_CPU_THIS_PTR PDPTR_CACHE.valid = 1; return 1; /* PDPTRs are fine */ } #if BX_SUPPORT_VMX >= 2 bx_bool BX_CPP_AttrRegparmN(1) BX_CPU_C::CheckPDPTR(Bit64u *pdptr) { for (int n=0; n<4; n++) { if (pdptr[n] & 0x1) { if (pdptr[n] & PAGING_PAE_PDPTE_RESERVED_BITS) return 0; } } return 1; /* PDPTRs are fine */ } #endif // Translate a linear address to a physical address in PAE paging mode bx_phy_address BX_CPU_C::translate_linear_PAE(bx_address laddr, Bit32u &lpf_mask, Bit32u &combined_access, unsigned curr_pl, unsigned rw) { bx_phy_address entry_addr[3], ppf; Bit64u entry[3]; bx_bool nx_fault = 0; unsigned pl = (curr_pl == 3); int leaf = BX_LEVEL_PTE; combined_access = 0x06; #if BX_SUPPORT_X86_64 if (long_mode()) { return translate_linear_long_mode(laddr, lpf_mask, combined_access, curr_pl, rw); } #endif if (! BX_CPU_THIS_PTR PDPTR_CACHE.valid) { BX_PANIC(("PDPTR_CACHE not valid !")); if (! CheckPDPTR(BX_CPU_THIS_PTR cr3)) { BX_ERROR(("translate_linear_PAE(): PDPTR check failed !")); exception(BX_GP_EXCEPTION, 0); } } entry[BX_LEVEL_PDPE] = BX_CPU_THIS_PTR PDPTR_CACHE.entry[(laddr >> 30) & 3]; int fault = check_entry_PAE("PDPE", entry[BX_LEVEL_PDPE], PAGING_PAE_PDPTE_RESERVED_BITS, rw, &nx_fault); if (fault >= 0) page_fault(fault, laddr, pl, rw); entry_addr[BX_LEVEL_PDE] = (bx_phy_address)((entry[BX_LEVEL_PDPE] & BX_CONST64(0x000ffffffffff000)) | ((laddr & 0x3fe00000) >> 18)); #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) entry_addr[BX_LEVEL_PDE] = translate_guest_physical(entry_addr[BX_LEVEL_PDE], laddr, 1, 1, rw); } #endif access_read_physical(entry_addr[BX_LEVEL_PDE], 8, &entry[BX_LEVEL_PDE]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[BX_LEVEL_PDE], 8, BX_PDE_ACCESS | BX_READ, (Bit8u*)(&entry[BX_LEVEL_PDE])); fault = check_entry_PAE("PDE", entry[BX_LEVEL_PDE], PAGING_PAE_RESERVED_BITS, rw, &nx_fault); if (fault >= 0) page_fault(fault, laddr, pl, rw); combined_access &= entry[BX_LEVEL_PDE] & 0x06; // U/S and R/W // Ignore CR4.PSE in PAE mode if (entry[BX_LEVEL_PDE] & 0x80) { if (entry[BX_LEVEL_PDE] & PAGING_PAE_PDE2M_RESERVED_BITS) { BX_DEBUG(("PAE PDE2M: reserved bit is set PDE=%08x:%08x", GET32H(entry[BX_LEVEL_PDE]), GET32L(entry[BX_LEVEL_PDE]))); page_fault(ERROR_RESERVED | ERROR_PROTECTION, laddr, pl, rw); } ppf = (bx_phy_address)((entry[BX_LEVEL_PDE] & BX_CONST64(0x000fffffffe00000)) | (laddr & 0x001ff000)); lpf_mask = 0x1fffff; leaf = BX_LEVEL_PDE; } else { // 4k pages, Get page table entry. entry_addr[BX_LEVEL_PTE] = (bx_phy_address)((entry[BX_LEVEL_PDE] & BX_CONST64(0x000ffffffffff000)) | ((laddr & 0x001ff000) >> 9)); #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) entry_addr[BX_LEVEL_PTE] = translate_guest_physical(entry_addr[BX_LEVEL_PTE], laddr, 1, 1, rw); } #endif access_read_physical(entry_addr[BX_LEVEL_PTE], 8, &entry[BX_LEVEL_PTE]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[BX_LEVEL_PTE], 8, BX_PTE_ACCESS | BX_READ, (Bit8u*)(&entry[BX_LEVEL_PTE])); fault = check_entry_PAE("PTE", entry[BX_LEVEL_PTE], PAGING_PAE_RESERVED_BITS, rw, &nx_fault); if (fault >= 0) page_fault(fault, laddr, pl, rw); combined_access &= entry[BX_LEVEL_PTE] & 0x06; // U/S and R/W // Make up the physical page frame address. ppf = (bx_phy_address)(entry[leaf] & BX_CONST64(0x000ffffffffff000)); lpf_mask = 0xfff; } bx_bool isWrite = (rw & 1); // write or r-m-w unsigned priv_index = (BX_CPU_THIS_PTR cr0.get_WP() << 4) | // bit 4 (pl<<3) | // bit 3 (combined_access | isWrite); // bit 2,1,0 if (!priv_check[priv_index] || nx_fault) page_fault(ERROR_PROTECTION, laddr, pl, rw); if (BX_CPU_THIS_PTR cr4.get_PGE()) combined_access |= (entry[leaf] & 0x100); // G if (leaf == BX_LEVEL_PTE) { // Update PDE A bit if needed. if (!(entry[BX_LEVEL_PDE] & 0x20)) { entry[BX_LEVEL_PDE] |= 0x20; access_write_physical(entry_addr[BX_LEVEL_PDE], 8, &entry[BX_LEVEL_PDE]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[BX_LEVEL_PDE], 8, (BX_PDE_ACCESS | BX_WRITE), (Bit8u*)(&entry[BX_LEVEL_PDE])); } } // Update A/D bits if needed. if (!(entry[leaf] & 0x20) || (isWrite && !(entry[leaf] & 0x40))) { entry[leaf] |= (0x20 | (isWrite<<6)); // Update A and possibly D bits access_write_physical(entry_addr[leaf], 8, &entry[leaf]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[leaf], 8, (BX_PTE_ACCESS + (leaf<<4)) | BX_WRITE, (Bit8u*)(&entry[leaf])); } return ppf; } #endif // Format of a PDE that Maps a 4-MByte Page // ----------------------------------------------------------- // 00 | Present (P) // 01 | R/W // 02 | U/S // 03 | Page-Level Write-Through (PWT) // 04 | Page-Level Cache-Disable (PCD) // 05 | Accessed (A) // 06 | Dirty (D) // 07 | Page size, must be 1 to indicate 4-Mbyte page // 08 | Global (G) (if CR4.PGE=1, ignored otherwise) // 11-09 | (ignored) // 12 | PAT (if PAT is supported, reserved otherwise) // PA-13 | Bits PA-32 of physical address of the 4-MByte page // 21-PA | Reserved (must be zero) // 31-22 | Bits 31-22 of physical address of the 4-MByte page // ----------------------------------------------------------- #define PAGING_PDE4M_RESERVED_BITS \ (((1 << (41-BX_PHY_ADDRESS_WIDTH))-1) << (13 + BX_PHY_ADDRESS_WIDTH - 32)) // Translate a linear address to a physical address bx_phy_address BX_CPU_C::translate_linear(bx_address laddr, unsigned curr_pl, unsigned rw) { Bit32u combined_access = 0x06; Bit32u lpf_mask = 0xfff; // 4K pages unsigned priv_index; // note - we assume physical memory < 4gig so for brevity & speed, we'll use // 32 bit entries although cr3 is expanded to 64 bits. bx_phy_address paddress, ppf, poffset = PAGE_OFFSET(laddr); bx_bool isWrite = rw & 1; // write or r-m-w unsigned pl = (curr_pl == 3); InstrTLB_Increment(tlbLookups); InstrTLB_Stats(); bx_address lpf = LPFOf(laddr); unsigned TLB_index = BX_TLB_INDEX_OF(lpf, 0); bx_TLB_entry *tlbEntry = &BX_CPU_THIS_PTR TLB.entry[TLB_index]; // already looked up TLB for code access if (TLB_LPFOf(tlbEntry->lpf) == lpf) { paddress = tlbEntry->ppf | poffset; bx_bool isExecute = (rw == BX_EXECUTE); if (! (tlbEntry->accessBits & ((isExecute<<2) | (isWrite<<1) | pl))) return paddress; // The current access does not have permission according to the info // in our TLB cache entry. Re-walk the page tables, in case there is // updated information in the memory image, and let the long path code // generate an exception if one is warranted. } if(BX_CPU_THIS_PTR cr0.get_PG()) { InstrTLB_Increment(tlbMisses); BX_DEBUG(("page walk for address 0x" FMT_LIN_ADDRX, laddr)); #if BX_CPU_LEVEL >= 6 if (BX_CPU_THIS_PTR cr4.get_PAE()) { ppf = translate_linear_PAE(laddr, lpf_mask, combined_access, curr_pl, rw); } else #endif { // CR4.PAE==0 (and EFER.LMA==0) Bit32u pde, pte, cr3_masked = BX_CPU_THIS_PTR cr3 & BX_CR3_PAGING_MASK; bx_phy_address pde_addr = (bx_phy_address) (cr3_masked | ((laddr & 0xffc00000) >> 20)); #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) pde_addr = translate_guest_physical(pde_addr, laddr, 1, 1, rw); } #endif access_read_physical(pde_addr, 4, &pde); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, pde_addr, 4, BX_PDE_ACCESS | BX_READ, (Bit8u*)(&pde)); if (!(pde & 0x1)) { BX_DEBUG(("PDE: entry not present")); page_fault(ERROR_NOT_PRESENT, laddr, pl, rw); } #if BX_CPU_LEVEL >= 5 if ((pde & 0x80) && BX_CPU_THIS_PTR cr4.get_PSE()) { // 4M paging, only if CR4.PSE enabled, ignore PDE.PS otherwise if (pde & PAGING_PDE4M_RESERVED_BITS) { BX_DEBUG(("PSE PDE4M: reserved bit is set: PDE=0x%08x", pde)); page_fault(ERROR_RESERVED | ERROR_PROTECTION, laddr, pl, rw); } // Combined access is just access from the pde (no pte involved). combined_access = pde & 0x06; // U/S and R/W priv_index = (BX_CPU_THIS_PTR cr0.get_WP() << 4) | // bit 4 (pl<<3) | // bit 3 (combined_access | isWrite); // bit 2,1,0 if (!priv_check[priv_index]) page_fault(ERROR_PROTECTION, laddr, pl, rw); #if BX_CPU_LEVEL >= 6 if (BX_CPU_THIS_PTR cr4.get_PGE()) combined_access |= pde & 0x100; // G #endif // Update PDE A/D bits if needed. if (!(pde & 0x20) || (isWrite && !(pde & 0x40))) { pde |= (0x20 | (isWrite<<6)); // Update A and possibly D bits access_write_physical(pde_addr, 4, &pde); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, pde_addr, 4, BX_PDE_ACCESS | BX_WRITE, (Bit8u*)(&pde)); } // make up the physical frame number ppf = (pde & 0xffc00000) | (laddr & 0x003ff000); #if BX_PHY_ADDRESS_WIDTH > 32 ppf |= ((bx_phy_address)(pde & 0x003fe000)) << 19; #endif lpf_mask = 0x3fffff; } else // else normal 4K page... #endif { // Get page table entry bx_phy_address pte_addr = (bx_phy_address)((pde & 0xfffff000) | ((laddr & 0x003ff000) >> 10)); #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) pte_addr = translate_guest_physical(pte_addr, laddr, 1, 1, rw); } #endif access_read_physical(pte_addr, 4, &pte); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, pte_addr, 4, BX_PTE_ACCESS | BX_READ, (Bit8u*)(&pte)); if (!(pte & 0x1)) { BX_DEBUG(("PTE: entry not present")); page_fault(ERROR_NOT_PRESENT, laddr, pl, rw); } // 386 and 486+ have different behaviour for combining // privilege from PDE and PTE. #if BX_CPU_LEVEL == 3 combined_access = (pde | pte) & 0x04; // U/S combined_access |= (pde & pte) & 0x02; // R/W #else // 486+ combined_access = (pde & pte) & 0x06; // U/S and R/W #endif priv_index = #if BX_CPU_LEVEL >= 4 (BX_CPU_THIS_PTR cr0.get_WP() << 4) | // bit 4 #endif (pl<<3) | // bit 3 (combined_access | isWrite); // bit 2,1,0 if (!priv_check[priv_index]) page_fault(ERROR_PROTECTION, laddr, pl, rw); #if BX_CPU_LEVEL >= 6 if (BX_CPU_THIS_PTR cr4.get_PGE()) combined_access |= (pte & 0x100); // G #endif // Update PDE A bit if needed. if (!(pde & 0x20)) { pde |= 0x20; access_write_physical(pde_addr, 4, &pde); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, pde_addr, 4, BX_PDE_ACCESS | BX_WRITE, (Bit8u*)(&pde)); } // Update PTE A/D bits if needed. if (!(pte & 0x20) || (isWrite && !(pte & 0x40))) { pte |= (0x20 | (isWrite<<6)); // Update A and possibly D bits access_write_physical(pte_addr, 4, &pte); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, pte_addr, 4, BX_PTE_ACCESS | BX_WRITE, (Bit8u*)(&pte)); } // Make up the physical page frame address. ppf = pte & 0xfffff000; } } #if BX_CPU_LEVEL >= 5 if (lpf_mask > 0xfff) BX_CPU_THIS_PTR TLB.split_large = 1; #endif } else { // no paging ppf = (bx_phy_address) lpf; } #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) { ppf = translate_guest_physical(ppf, laddr, 1, 0, rw); } } #endif // Calculate physical memory address and fill in TLB cache entry paddress = ppf | poffset; // direct memory access is NOT allowed by default tlbEntry->lpf = lpf | TLB_HostPtr; tlbEntry->lpf_mask = lpf_mask; tlbEntry->ppf = ppf; tlbEntry->accessBits = 0; if ((combined_access & 4) == 0) { // System tlbEntry->accessBits |= TLB_SysOnly; if (! isWrite) tlbEntry->accessBits |= TLB_ReadOnly; } else { // Current operation is a read or a page is read only // Not efficient handling of system write to user read only page: // hopefully it is very rare case, optimize later if (! isWrite || (combined_access & 2) == 0) { tlbEntry->accessBits |= TLB_ReadOnly; } } #if BX_CPU_LEVEL >= 6 if (combined_access & 0x100) // Global bit tlbEntry->accessBits |= TLB_GlobalPage; #endif #if BX_SUPPORT_X86_64 // EFER.NXE change won't flush TLB if (BX_CPU_THIS_PTR cr4.get_PAE() && rw != BX_EXECUTE) tlbEntry->accessBits |= TLB_NoExecute; #endif // Attempt to get a host pointer to this physical page. Put that // pointer in the TLB cache. Note if the request is vetoed, NULL // will be returned, and it's OK to OR zero in anyways. tlbEntry->hostPageAddr = BX_CPU_THIS_PTR getHostMemAddr(ppf, rw); if (tlbEntry->hostPageAddr) { // All access allowed also via direct pointer #if BX_X86_DEBUGGER if (! hwbreakpoint_check(laddr)) #endif tlbEntry->lpf = lpf; // allow direct access with HostPtr } return paddress; } #if BX_SUPPORT_VMX >= 2 /* EPT access type */ #define BX_EPT_READ 0x01 #define BX_EPT_WRITE 0x02 #define BX_EPT_EXECUTE 0x04 /* EPT access mask */ #define BX_EPT_ENTRY_NOT_PRESENT 0x00 #define BX_EPT_ENTRY_READ_ONLY 0x01 #define BX_EPT_ENTRY_WRITE_ONLY 0x02 #define BX_EPT_ENTRY_READ_WRITE 0x03 #define BX_EPT_ENTRY_EXECUTE_ONLY 0x04 #define BX_EPT_ENTRY_READ_EXECUTE 0x05 #define BX_EPT_ENTRY_WRITE_EXECUTE 0x06 #define BX_EPT_ENTRY_READ_WRITE_EXECUTE 0x07 // Format of a EPT Entry // ----------------------------------------------------------- // 00 | Read access // 01 | Write access // 02 | Execute Access // 05-03 | EPT Memory type (for leaf entries, reserved otherwise) // 06 | Ignore PAT memory type (for leaf entries, reserved otherwise) // 07 | Page Size, must be 1 to indicate a Large Page // 11-08 | (ignored) // PA-12 | Physical address // 51-PA | Reserved (must be zero) // 63-52 | (ignored) // ----------------------------------------------------------- #define PAGING_EPT_RESERVED_BITS (BX_PAGING_PHY_ADDRESS_RESERVED_BITS) bx_phy_address BX_CPU_C::translate_guest_physical(bx_phy_address guest_paddr, bx_address guest_laddr, bx_bool guest_laddr_valid, bx_bool is_page_walk, unsigned rw) { VMCS_CACHE *vm = &BX_CPU_THIS_PTR vmcs; bx_phy_address entry_addr[4], ppf = 0, pbase = LPFOf(vm->eptptr); Bit64u entry[4]; int leaf = BX_LEVEL_PTE; Bit32u combined_access = 0x7, access_mask = 0; BX_DEBUG(("EPT walk for guest paddr 0x" FMT_ADDRX, guest_paddr)); if (rw == BX_EXECUTE) access_mask |= BX_EPT_EXECUTE; if (rw & 1) access_mask |= BX_EPT_WRITE; // write or r-m-w if (rw == BX_READ) access_mask |= BX_EPT_READ; Bit32u vmexit_reason = 0, vmexit_qualification = access_mask; for (leaf = BX_LEVEL_PML4;; --leaf) { entry_addr[leaf] = pbase + ((guest_paddr >> (9 + 9*leaf)) & 0xff8); access_read_physical(entry_addr[leaf], 8, &entry[leaf]); BX_DBG_PHY_MEMORY_ACCESS(BX_CPU_ID, entry_addr[leaf], 8, (BX_EPT_PTE_ACCESS + (leaf<<4)) | BX_READ, (Bit8u*)(&entry[leaf])); Bit64u curr_entry = entry[leaf]; Bit32u curr_access_mask = curr_entry & 0x7; combined_access &= curr_access_mask; if (curr_access_mask == BX_EPT_ENTRY_NOT_PRESENT) { BX_DEBUG(("EPT %s: not present", bx_paging_level[leaf])); vmexit_reason = VMX_VMEXIT_EPT_VIOLATION; break; } if (curr_access_mask == BX_EPT_ENTRY_WRITE_ONLY || curr_access_mask == BX_EPT_ENTRY_WRITE_EXECUTE) { BX_DEBUG(("EPT %s: EPT misconfiguration mask=%d", bx_paging_level[leaf], curr_access_mask)); vmexit_reason = VMX_VMEXIT_EPT_MISCONFIGURATION; break; } extern bx_bool isMemTypeValidMTRR(unsigned memtype); if (! isMemTypeValidMTRR((curr_entry >> 3) & 7)) { BX_DEBUG(("EPT %s: EPT misconfiguration memtype=%d", bx_paging_level[leaf], (curr_entry >> 3) & 7)); vmexit_reason = VMX_VMEXIT_EPT_MISCONFIGURATION; break; } if (curr_entry & PAGING_EPT_RESERVED_BITS) { BX_DEBUG(("EPT %s: reserved bit is set %08x:%08x", bx_paging_level[leaf], GET32H(curr_entry), GET32L(curr_entry))); vmexit_reason = VMX_VMEXIT_EPT_MISCONFIGURATION; break; } pbase = curr_entry & BX_CONST64(0x000ffffffffff000); if (leaf == BX_LEVEL_PTE) { // Make up the physical page frame address. ppf = (bx_phy_address)(curr_entry & BX_CONST64(0x000ffffffffff000)); break; } if (curr_entry & 0x80) { if (leaf > (BX_LEVEL_PDE + !!bx_cpuid_support_1g_paging())) { BX_DEBUG(("EPT %s: PS bit set !")); vmexit_reason = VMX_VMEXIT_EPT_VIOLATION; break; } if (leaf == BX_LEVEL_PDPE) { if (curr_entry & PAGING_PAE_PDPTE1G_RESERVED_BITS) { BX_DEBUG(("EPT PDPE1G: reserved bit is set: PDPE=%08x:%08x", GET32H(curr_entry), GET32L(curr_entry))); vmexit_reason = VMX_VMEXIT_EPT_VIOLATION; break; } // Make up the physical page frame address. ppf = (bx_phy_address)((curr_entry & BX_CONST64(0x000fffffc0000000)) | (guest_paddr & 0x3ffff000)); break; } if (leaf == BX_LEVEL_PDE) { if (curr_entry & PAGING_PAE_PDE2M_RESERVED_BITS) { BX_DEBUG(("EPT PDE2M: reserved bit is set PDE=%08x:%08x", GET32H(curr_entry), GET32L(curr_entry))); vmexit_reason = VMX_VMEXIT_EPT_VIOLATION; break; } // Make up the physical page frame address. ppf = (bx_phy_address)((curr_entry & BX_CONST64(0x000fffffffe00000)) | (guest_paddr & 0x001ff000)); break; } } } if ((access_mask & combined_access) != access_mask) { vmexit_reason = VMX_VMEXIT_EPT_VIOLATION; } if (vmexit_reason) { BX_ERROR(("VMEXIT: EPT %s for guest paddr 0x" FMT_ADDRX " laddr " FMT_ADDRX, (vmexit_reason == VMX_VMEXIT_EPT_VIOLATION) ? "violation" : "misconfig", guest_paddr, guest_laddr)); VMwrite64(VMCS_64BIT_GUEST_PHYSICAL_ADDR, guest_paddr); if (guest_laddr_valid) { VMwrite64(VMCS_GUEST_LINEAR_ADDR, guest_laddr); vmexit_qualification |= 0x80; if (is_page_walk) vmexit_qualification |= 0x100; } VMexit(0, vmexit_reason, vmexit_qualification | (combined_access << 3)); } Bit32u page_offset = PAGE_OFFSET(guest_paddr); return ppf | page_offset; } #endif #if BX_DEBUGGER || BX_DISASM || BX_INSTRUMENTATION || BX_GDBSTUB #if BX_DEBUGGER void dbg_print_paging_pte(int level, Bit64u entry) { dbg_printf("%4s: 0x%08x%08x", bx_paging_level[level], GET32H(entry), GET32L(entry)); if (level == BX_LEVEL_PTE) { dbg_printf(" %s %s %s", (entry & 0x0100) ? "G" : "g", (entry & 0x0080) ? "PAT" : "pat", (entry & 0x0040) ? "D" : "d"); } else { if (entry & 0x80) { dbg_printf(" PS %s %s %s", (entry & 0x0100) ? "G" : "g", (entry & 0x1000) ? "PAT" : "pat", (entry & 0x0040) ? "D" : "d"); } else { dbg_printf(" ps "); } } dbg_printf(" %s %s %s %s %s %s\n", (entry & 0x20) ? "A" : "a", (entry & 0x10) ? "PCD" : "pcd", (entry & 0x08) ? "PWT" : "pwt", (entry & 0x04) ? "U" : "S", (entry & 0x02) ? "W" : "R", (entry & 0x01) ? "P" : "p"); } #if BX_SUPPORT_VMX >= 2 void dbg_print_ept_paging_pte(int level, Bit64u entry) { dbg_printf("EPT %4s: 0x%08x%08x", bx_paging_level[level], GET32H(entry), GET32L(entry)); if (level != BX_LEVEL_PTE && (entry & 0x80)) dbg_printf(" PS"); else dbg_printf(" "); dbg_printf(" %s %s %s\n", (entry & 0x04) ? "E" : "e", (entry & 0x02) ? "W" : "w", (entry & 0x01) ? "R" : "r"); } #endif #endif // BX_DEBUGGER #if BX_SUPPORT_VMX >= 2 bx_bool BX_CPU_C::dbg_translate_guest_physical(bx_phy_address guest_paddr, bx_phy_address *phy, bx_bool verbose) { VMCS_CACHE *vm = &BX_CPU_THIS_PTR vmcs; bx_phy_address pt_address = LPFOf(vm->eptptr); Bit64u offset_mask = BX_CONST64(0x0000ffffffffffff); for (int level = 3; level >= 0; --level) { Bit64u pte; pt_address += ((guest_paddr >> (9 + 9*level)) & 0xff8); offset_mask >>= 9; BX_MEM(0)->readPhysicalPage(BX_CPU_THIS, pt_address, 8, &pte); #if BX_DEBUGGER if (verbose) dbg_print_ept_paging_pte(level, pte); #endif switch(pte & 7) { case BX_EPT_ENTRY_NOT_PRESENT: case BX_EPT_ENTRY_WRITE_ONLY: case BX_EPT_ENTRY_WRITE_EXECUTE: return 0; } if (pte & BX_PAGING_PHY_ADDRESS_RESERVED_BITS) return 0; pt_address = bx_phy_address(pte & BX_CONST64(0x000ffffffffff000)); if (level == BX_LEVEL_PTE) break; if (pte & 0x80) { if (level > (BX_LEVEL_PDE + !!bx_cpuid_support_1g_paging())) return 0; pt_address &= BX_CONST64(0x000fffffffffe000); if (pt_address & offset_mask) return 0; break; } } *phy = pt_address + (bx_phy_address)(guest_paddr & offset_mask); return 1; } #endif bx_bool BX_CPU_C::dbg_xlate_linear2phy(bx_address laddr, bx_phy_address *phy, bx_bool verbose) { if (! BX_CPU_THIS_PTR cr0.get_PG()) { *phy = (bx_phy_address) laddr; return 1; } bx_phy_address paddress; bx_phy_address pt_address = BX_CPU_THIS_PTR cr3 & BX_CR3_PAGING_MASK; // see if page is in the TLB first if (! verbose) { bx_address lpf = LPFOf(laddr); unsigned TLB_index = BX_TLB_INDEX_OF(lpf, 0); bx_TLB_entry *tlbEntry = &BX_CPU_THIS_PTR TLB.entry[TLB_index]; if (TLB_LPFOf(tlbEntry->lpf) == lpf) { paddress = tlbEntry->ppf | PAGE_OFFSET(laddr); *phy = paddress; return 1; } } #if BX_CPU_LEVEL >= 6 if (BX_CPU_THIS_PTR cr4.get_PAE()) { Bit64u offset_mask = BX_CONST64(0x0000ffffffffffff); int level = 3; if (! long_mode()) { if (! BX_CPU_THIS_PTR PDPTR_CACHE.valid) goto page_fault; pt_address = BX_CPU_THIS_PTR PDPTR_CACHE.entry[(laddr >> 30) & 3] & BX_CONST64(0x000ffffffffff000); offset_mask >>= 18; level = 1; } for (; level >= 0; --level) { Bit64u pte; pt_address += ((laddr >> (9 + 9*level)) & 0xff8); offset_mask >>= 9; #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) { if (! dbg_translate_guest_physical(pt_address, &pt_address, verbose)) goto page_fault; } } #endif BX_MEM(0)->readPhysicalPage(BX_CPU_THIS, pt_address, 8, &pte); #if BX_DEBUGGER if (verbose) dbg_print_paging_pte(level, pte); #endif if(!(pte & 1)) goto page_fault; if (pte & BX_PAGING_PHY_ADDRESS_RESERVED_BITS) goto page_fault; pt_address = bx_phy_address(pte & BX_CONST64(0x000ffffffffff000)); if (level == BX_LEVEL_PTE) break; if (pte & 0x80) { // 2M page if (level == BX_LEVEL_PDE) { pt_address &= BX_CONST64(0x000fffffffffe000); if (pt_address & offset_mask) goto page_fault; break; } // 1G page if (bx_cpuid_support_1g_paging() && level == BX_LEVEL_PDPE && long_mode()) { pt_address &= BX_CONST64(0x000fffffffffe000); if (pt_address & offset_mask) goto page_fault; break; } goto page_fault; } } paddress = pt_address + (bx_phy_address)(laddr & offset_mask); } else // not PAE #endif { Bit32u offset_mask = 0xfff; for (int level = 1; level >= 0; --level) { Bit32u pte; pt_address += ((laddr >> (10 + 10*level)) & 0xffc); #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) { if (! dbg_translate_guest_physical(pt_address, &pt_address, verbose)) goto page_fault; } } #endif BX_MEM(0)->readPhysicalPage(BX_CPU_THIS, pt_address, 4, &pte); #if BX_DEBUGGER if (verbose) dbg_print_paging_pte(level, pte); #endif if (!(pte & 1)) goto page_fault; pt_address = pte & 0xfffff000; #if BX_CPU_LEVEL >= 6 if (level == BX_LEVEL_PDE && (pte & 0x80) != 0 && BX_CPU_THIS_PTR cr4.get_PSE()) { offset_mask = 0x3fffff; pt_address = pte & 0xffc00000; #if BX_PHY_ADDRESS_WIDTH > 32 pt_address += ((bx_phy_address)(pte & 0x003fe000)) << 19; #endif break; } #endif } paddress = pt_address + (bx_phy_address)(laddr & offset_mask); } #if BX_SUPPORT_VMX >= 2 if (BX_CPU_THIS_PTR in_vmx_guest) { if (SECONDARY_VMEXEC_CONTROL(VMX_VM_EXEC_CTRL3_EPT_ENABLE)) { if (! dbg_translate_guest_physical(paddress, &paddress, verbose)) goto page_fault; } } #endif *phy = paddress; return 1; page_fault: *phy = 0; return 0; } #endif void BX_CPU_C::access_write_linear(bx_address laddr, unsigned len, unsigned curr_pl, void *data) { #if BX_X86_DEBUGGER hwbreakpoint_match(laddr, len, BX_WRITE); #endif Bit32u pageOffset = PAGE_OFFSET(laddr); /* check for reference across multiple pages */ if ((pageOffset + len) <= 4096) { // Access within single page. BX_CPU_THIS_PTR address_xlation.paddress1 = dtranslate_linear(laddr, curr_pl, BX_WRITE); BX_CPU_THIS_PTR address_xlation.pages = 1; BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, len, BX_WRITE); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, len, curr_pl, BX_WRITE, (Bit8u*) data); access_write_physical(BX_CPU_THIS_PTR address_xlation.paddress1, len, data); } else { // access across 2 pages BX_CPU_THIS_PTR address_xlation.paddress1 = dtranslate_linear(laddr, curr_pl, BX_WRITE); BX_CPU_THIS_PTR address_xlation.len1 = 4096 - pageOffset; BX_CPU_THIS_PTR address_xlation.len2 = len - BX_CPU_THIS_PTR address_xlation.len1; BX_CPU_THIS_PTR address_xlation.pages = 2; bx_address laddr2 = laddr + BX_CPU_THIS_PTR address_xlation.len1; BX_CPU_THIS_PTR address_xlation.paddress2 = dtranslate_linear(laddr2, curr_pl, BX_WRITE); #ifdef BX_LITTLE_ENDIAN BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, BX_WRITE); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, curr_pl, BX_WRITE, (Bit8u*) data); access_write_physical(BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, data); BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, BX_WRITE); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, curr_pl, BX_WRITE, ((Bit8u*)data) + BX_CPU_THIS_PTR address_xlation.len1); access_write_physical(BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, ((Bit8u*)data) + BX_CPU_THIS_PTR address_xlation.len1); #else // BX_BIG_ENDIAN BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, BX_WRITE); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, curr_pl, BX_WRITE, ((Bit8u*)data) + (len - BX_CPU_THIS_PTR address_xlation.len1)); access_write_physical(BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, ((Bit8u*)data) + (len - BX_CPU_THIS_PTR address_xlation.len1)); BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, BX_WRITE); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, curr_pl, BX_WRITE, (Bit8u*) data); access_write_physical(BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, data); #endif } } void BX_CPU_C::access_read_linear(bx_address laddr, unsigned len, unsigned curr_pl, unsigned xlate_rw, void *data) { BX_ASSERT(xlate_rw == BX_READ || xlate_rw == BX_RW); #if BX_X86_DEBUGGER hwbreakpoint_match(laddr, len, xlate_rw); #endif Bit32u pageOffset = PAGE_OFFSET(laddr); /* check for reference across multiple pages */ if ((pageOffset + len) <= 4096) { // Access within single page. BX_CPU_THIS_PTR address_xlation.paddress1 = dtranslate_linear(laddr, curr_pl, xlate_rw); BX_CPU_THIS_PTR address_xlation.pages = 1; access_read_physical(BX_CPU_THIS_PTR address_xlation.paddress1, len, data); BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, len, xlate_rw); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, len, curr_pl, BX_READ, (Bit8u*) data); } else { // access across 2 pages BX_CPU_THIS_PTR address_xlation.paddress1 = dtranslate_linear(laddr, curr_pl, xlate_rw); BX_CPU_THIS_PTR address_xlation.len1 = 4096 - pageOffset; BX_CPU_THIS_PTR address_xlation.len2 = len - BX_CPU_THIS_PTR address_xlation.len1; BX_CPU_THIS_PTR address_xlation.pages = 2; bx_address laddr2 = laddr + BX_CPU_THIS_PTR address_xlation.len1; BX_CPU_THIS_PTR address_xlation.paddress2 = dtranslate_linear(laddr2, curr_pl, xlate_rw); #ifdef BX_LITTLE_ENDIAN access_read_physical(BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, data); BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, xlate_rw); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, curr_pl, BX_READ, (Bit8u*) data); access_read_physical(BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, ((Bit8u*)data) + BX_CPU_THIS_PTR address_xlation.len1); BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, xlate_rw); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, curr_pl, BX_READ, ((Bit8u*)data) + BX_CPU_THIS_PTR address_xlation.len1); #else // BX_BIG_ENDIAN access_read_physical(BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, ((Bit8u*)data) + (len - BX_CPU_THIS_PTR address_xlation.len1)); BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, xlate_rw); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr, BX_CPU_THIS_PTR address_xlation.paddress1, BX_CPU_THIS_PTR address_xlation.len1, curr_pl, BX_READ, ((Bit8u*)data) + (len - BX_CPU_THIS_PTR address_xlation.len1)); access_read_physical(BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, data); BX_INSTR_LIN_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, xlate_rw); BX_DBG_LIN_MEMORY_ACCESS(BX_CPU_ID, laddr2, BX_CPU_THIS_PTR address_xlation.paddress2, BX_CPU_THIS_PTR address_xlation.len2, curr_pl, BX_READ, (Bit8u*) data); #endif } } void BX_CPU_C::access_write_physical(bx_phy_address paddr, unsigned len, void *data) { #if BX_SUPPORT_VMX >= 2 if (is_virtual_apic_page(paddr)) { VMX_Virtual_Apic_Write(paddr, len, data); return; } #endif #if BX_SUPPORT_APIC if (BX_CPU_THIS_PTR lapic.is_selected(paddr)) { BX_CPU_THIS_PTR lapic.write(paddr, data, len); return; } #endif BX_MEM(0)->writePhysicalPage(BX_CPU_THIS, paddr, len, data); } void BX_CPU_C::access_read_physical(bx_phy_address paddr, unsigned len, void *data) { #if BX_SUPPORT_VMX >= 2 if (is_virtual_apic_page(paddr)) { VMX_Virtual_Apic_Read(paddr, len, data); return; } #endif #if BX_SUPPORT_APIC if (BX_CPU_THIS_PTR lapic.is_selected(paddr)) { BX_CPU_THIS_PTR lapic.read(paddr, data, len); return; } #endif BX_MEM(0)->readPhysicalPage(BX_CPU_THIS, paddr, len, data); } bx_hostpageaddr_t BX_CPU_C::getHostMemAddr(bx_phy_address ppf, unsigned rw) { #if BX_SUPPORT_VMX >= 2 if (is_virtual_apic_page(ppf)) return 0; // Do not allow direct access to virtual apic page #endif #if BX_SUPPORT_APIC if (BX_CPU_THIS_PTR lapic.is_selected(ppf)) return 0; // Vetoed! APIC address space #endif return (bx_hostpageaddr_t) BX_MEM(0)->getHostMemAddr(BX_CPU_THIS, ppf, rw); }