/* $Id: DBGFCoreWrite.cpp 32595 2010-09-17 12:34:48Z vboxsync $ */ /** @file * DBGF - Debugger Facility, Guest Core Dump. */ /* * Copyright (C) 2010 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. */ /* * VBox VMCore Format: * [ ELF 64 Header] -- Only 1 * * [ PT_NOTE ] -- Only 1 * - Offset into CoreDescriptor followed by list of Notes (Note Hdr + data) of VBox CPUs. * - (Any Additional custom Note sections) * * [ PT_LOAD ] -- One for each contiguous memory chunk * - Memory offset * - File offset * * CoreDescriptor * - Magic, VBox version * - Number of CPus * * Per-CPU register dump * - CPU 1 Note Hdr + Data * - CPU 2 Note Hdr + Data * ... * (Additional custom notes Hdr+data) * - VBox 1 Note Hdr + Data * - VBox 2 Note Hdr + Data * ... * Memory dump * */ /******************************************************************************* * Header Files * *******************************************************************************/ #define LOG_GROUP LOG_GROUP_DBGF #include #include #include "DBGFInternal.h" #include #include "CPUMInternal.h" #include #include #include #include #include #include #include #include #include "../Runtime/include/internal/ldrELF64.h" /******************************************************************************* * Defined Constants And Macros * *******************************************************************************/ #ifdef DEBUG_ramshankar # undef Log # define Log LogRel #endif #define DBGFLOG_NAME "DBGFCoreWrite" static const int s_NoteAlign = 8; static const int s_cbNoteName = 16; /* These strings *HAVE* to be 8-byte aligned */ static const char *s_pcszCoreVBoxCore = "VBCORE"; static const char *s_pcszCoreVBoxCpu = "VBCPU"; /** * DBGFCOREDATA: Core data. */ typedef struct { const char *pszDumpPath; /* File path to dump the core into. */ } DBGFCOREDATA, *PDBGFCOREDATA; /** * ELF function to write 64-bit ELF header. * * @param hFile The file to write to. * @param cProgHdrs Number of program headers. * @param cSecHdrs Number of section headers. * @param pcbElfHdr Where to store the size of written header to file, * can be NULL. * * @return IPRT status code. */ static int Elf64WriteElfHdr(RTFILE hFile, uint16_t cProgHdrs, uint16_t cSecHdrs, uint64_t *pcbElfHdr) { Elf64_Ehdr ElfHdr; RT_ZERO(ElfHdr); ElfHdr.e_ident[EI_MAG0] = ELFMAG0; ElfHdr.e_ident[EI_MAG1] = ELFMAG1; ElfHdr.e_ident[EI_MAG2] = ELFMAG2; ElfHdr.e_ident[EI_MAG3] = ELFMAG3; ElfHdr.e_ident[EI_DATA] = ELFDATA2LSB; ElfHdr.e_type = ET_CORE; ElfHdr.e_version = EV_CURRENT; ElfHdr.e_ident[EI_CLASS] = ELFCLASS64; /* 32-bit VMs will produce cores with e_machine EM_386. */ #ifdef RT_ARCH_AMD64 ElfHdr.e_machine = EM_X86_64; #else ElfHdr.e_machine = EM_386; #endif ElfHdr.e_phnum = cProgHdrs; ElfHdr.e_shnum = cSecHdrs; ElfHdr.e_ehsize = sizeof(ElfHdr); ElfHdr.e_phoff = sizeof(ElfHdr); ElfHdr.e_phentsize = sizeof(Elf64_Phdr); ElfHdr.e_shentsize = sizeof(Elf64_Shdr); int rc = RTFileWrite(hFile, &ElfHdr, sizeof(ElfHdr), NULL /* all */); if (RT_SUCCESS(rc) && pcbElfHdr) *pcbElfHdr = sizeof(ElfHdr); return rc; } /** * ELF function to write 64-bit program header. * * @param hFile The file to write to. * @param Type Type of program header (PT_*). * @param fFlags Flags (access permissions, PF_*). * @param offFileData File offset of contents. * @param cbFileData Size of contents in the file. * @param cbMemData Size of contents in memory. * @param Phys Physical address, pass zero if not applicable. * @param pcbProgHdr Where to store the size of written header to file, * can be NULL. * * @return IPRT status code. */ static int Elf64WriteProgHdr(RTFILE hFile, uint32_t Type, uint32_t fFlags, uint64_t offFileData, uint64_t cbFileData, uint64_t cbMemData, RTGCPHYS Phys, uint64_t *pcbProgHdr) { Elf64_Phdr ProgHdr; RT_ZERO(ProgHdr); ProgHdr.p_type = Type; ProgHdr.p_flags = fFlags; ProgHdr.p_offset = offFileData; ProgHdr.p_filesz = cbFileData; ProgHdr.p_memsz = cbMemData; ProgHdr.p_paddr = Phys; int rc = RTFileWrite(hFile, &ProgHdr, sizeof(ProgHdr), NULL /* all */); if (RT_SUCCESS(rc) && pcbProgHdr) *pcbProgHdr = sizeof(ProgHdr); return rc; } /** * Returns the size of the NOTE section given the name and size of the data. * * @param pszName Name of the note section. * @param cb Size of the data portion of the note section. * * @return The size of the NOTE section as rounded to the file alignment. */ static inline uint64_t Elf64NoteSectionSize(const char *pszName, uint64_t cbData) { uint64_t cbNote = sizeof(Elf64_Nhdr); size_t cchName = strlen(pszName) + 1; size_t cchNameAlign = RT_ALIGN_Z(cchName, s_NoteAlign); cbNote += cchNameAlign; cbNote += RT_ALIGN_64(cbData, s_NoteAlign); return cbNote; } /** * Elf function to write 64-bit note header. * * @param hFile The file to write to. * @param Type Type of this section. * @param pszName Name of this section. * @param pcv Opaque pointer to the data, if NULL only computes size. * @param cbData Size of the data. * @param pcbNoteHdr Where to store the size of written header to file, * can be NULL. * * @return IPRT status code. */ static int Elf64WriteNoteHdr(RTFILE hFile, uint16_t Type, const char *pszName, const void *pcvData, uint64_t cbData, uint64_t *pcbNoteHdr) { AssertReturn(pcvData, VERR_INVALID_POINTER); AssertReturn(cbData > 0, VERR_NO_DATA); char szNoteName[s_cbNoteName]; RT_ZERO(szNoteName); RTStrCopy(szNoteName, sizeof(szNoteName), pszName); size_t cchName = strlen(szNoteName) + 1; size_t cchNameAlign = RT_ALIGN_Z(cchName, s_NoteAlign); uint64_t cbDataAlign = RT_ALIGN_64(cbData, s_NoteAlign); /* * Yell loudly and bail if we are going to be writing a core file that is not compatible with * both Solaris and the 64-bit ELF spec. which dictates 8-byte alignment. See #5211 comment 3. */ if (cchNameAlign - cchName > 3) { LogRel((DBGFLOG_NAME ": Elf64WriteNoteHdr pszName=%s cchName=%u cchNameAlign=%u, cchName aligns to 4 not 8-bytes!\n", pszName, cchName, cchNameAlign)); return VERR_INVALID_PARAMETER; } if (cbDataAlign - cbData > 3) { LogRel((DBGFLOG_NAME ": Elf64WriteNoteHdr pszName=%s cbData=%u cbDataAlign=%u, cbData aligns to 4 not 8-bytes!\n", pszName, cbData, cbDataAlign)); return VERR_INVALID_PARAMETER; } static const char s_achPad[7] = { 0, 0, 0, 0, 0, 0, 0 }; AssertCompile(sizeof(s_achPad) >= s_NoteAlign - 1); Elf64_Nhdr ElfNoteHdr; RT_ZERO(ElfNoteHdr); ElfNoteHdr.n_namesz = (Elf64_Word)cchName - 1; /* Again a discrepancy between ELF-64 and Solaris (#5211 comment 3), we will follow ELF-64 */ ElfNoteHdr.n_type = Type; ElfNoteHdr.n_descsz = (Elf64_Word)cbDataAlign; /* * Write note header. */ int rc = RTFileWrite(hFile, &ElfNoteHdr, sizeof(ElfNoteHdr), NULL /* all */); if (RT_SUCCESS(rc)) { /* * Write note name. */ rc = RTFileWrite(hFile, szNoteName, cchName, NULL /* all */); if (RT_SUCCESS(rc)) { /* * Write note name padding if required. */ if (cchNameAlign > cchName) rc = RTFileWrite(hFile, s_achPad, cchNameAlign - cchName, NULL); if (RT_SUCCESS(rc)) { /* * Write note data. */ rc = RTFileWrite(hFile, pcvData, cbData, NULL /* all */); if (RT_SUCCESS(rc)) { /* * Write note data padding if required. */ if (cbDataAlign > cbData) rc = RTFileWrite(hFile, s_achPad, cbDataAlign - cbData, NULL /* all*/); } } } } if (RT_FAILURE(rc)) LogRel((DBGFLOG_NAME ": RTFileWrite failed. rc=%Rrc pszName=%s cchName=%u cchNameAlign=%u cbData=%u cbDataAlign=%u\n", rc, pszName, cchName, cchNameAlign, cbData, cbDataAlign)); return rc; } /** * Count the number of memory ranges that go into the core file. * * We cannot do a page-by-page dump of the entire guest memory as there will be * way too many program header entries. Also we don't want to dump MMIO regions * which means we cannot have a 1:1 mapping between core file offset and memory * offset. Instead we dump the memory in ranges. A memory range is a contiguous * memory area suitable for dumping to a core file. * * @param pVM The VM handle. * * @return Number of memory ranges */ static uint32_t dbgfR3GetRamRangeCount(PVM pVM) { return PGMR3PhysGetRamRangeCount(pVM); } /** * EMT Rendezvous worker function for DBGFR3CoreWrite. * * @param pVM The VM handle. * @param pVCpu The handle of the calling VCPU. * @param pvData Opaque data. * * @return VBox status code. */ static DECLCALLBACK(VBOXSTRICTRC) dbgfR3CoreWrite(PVM pVM, PVMCPU pVCpu, void *pvData) { /* * Validate input. */ AssertReturn(pVM, VERR_INVALID_VM_HANDLE); AssertReturn(pVCpu, VERR_INVALID_VMCPU_HANDLE); AssertReturn(pvData, VERR_INVALID_POINTER); PDBGFCOREDATA pDbgfData = (PDBGFCOREDATA)pvData; /* * Collect core information. */ uint32_t u32MemRanges = dbgfR3GetRamRangeCount(pVM); uint16_t cMemRanges = u32MemRanges < UINT16_MAX - 1 ? u32MemRanges : UINT16_MAX - 1; /* One PT_NOTE Program header */ uint16_t cProgHdrs = cMemRanges + 1; DBGFCOREDESCRIPTOR CoreDescriptor; RT_ZERO(CoreDescriptor); CoreDescriptor.u32Magic = DBGFCORE_MAGIC; CoreDescriptor.u32FmtVersion = DBGFCORE_FMT_VERSION; CoreDescriptor.cbSelf = sizeof(CoreDescriptor); CoreDescriptor.u32VBoxVersion = VBOX_FULL_VERSION; CoreDescriptor.u32VBoxRevision = VMMGetSvnRev(); CoreDescriptor.cCpus = pVM->cCpus; Log((DBGFLOG_NAME ": CoreDescriptor Version=%u Revision=%u\n", CoreDescriptor.u32VBoxVersion, CoreDescriptor.u32VBoxRevision)); /* * Compute total size of the note section. */ uint64_t cbNoteSection = Elf64NoteSectionSize(s_pcszCoreVBoxCore, sizeof(CoreDescriptor)) + pVM->cCpus * Elf64NoteSectionSize(s_pcszCoreVBoxCpu, sizeof(CPUMCTX)); uint64_t off = 0; /* * Create the core file. */ RTFILE hFile = NIL_RTFILE; int rc = RTFileOpen(&hFile, pDbgfData->pszDumpPath, RTFILE_O_CREATE_REPLACE | RTFILE_O_READWRITE); if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": RTFileOpen failed for '%s' rc=%Rrc\n", pDbgfData->pszDumpPath, rc)); return rc; } /* * Write ELF header. */ uint64_t cbElfHdr = 0; uint64_t cbProgHdr = 0; uint64_t offMemRange = 0; rc = Elf64WriteElfHdr(hFile, cProgHdrs, 0 /* cSecHdrs */, &cbElfHdr); off += cbElfHdr; if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": Elf64WriteElfHdr failed. rc=%Rrc\n", rc)); goto CoreWriteDone; } /* * Write PT_NOTE program header. */ rc = Elf64WriteProgHdr(hFile, PT_NOTE, PF_R, cbElfHdr + cProgHdrs * sizeof(Elf64_Phdr), /* file offset to contents */ cbNoteSection, /* size in core file */ cbNoteSection, /* size in memory */ 0, /* physical address */ &cbProgHdr); Assert(cbProgHdr == sizeof(Elf64_Phdr)); off += cbProgHdr; if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": Elf64WritreProgHdr failed for PT_NOTE. rc=%Rrc\n", rc)); goto CoreWriteDone; } /* * Write PT_LOAD program header for each memory range. */ offMemRange = off + cbNoteSection; for (uint16_t iRange = 0; iRange < cMemRanges; iRange++) { RTGCPHYS GCPhysStart; RTGCPHYS GCPhysEnd; bool fIsMmio; rc = PGMR3PhysGetRange(pVM, iRange, &GCPhysStart, &GCPhysEnd, NULL /* pszDesc */, &fIsMmio); if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": PGMR3PhysGetRange failed for iRange(%u) rc=%Rrc\n", iRange, rc)); goto CoreWriteDone; } uint64_t cbMemRange = GCPhysEnd - GCPhysStart + 1; uint64_t cbFileRange = fIsMmio ? 0 : cbMemRange; Log((DBGFLOG_NAME ": PGMR3PhysGetRange iRange=%u GCPhysStart=%#x GCPhysEnd=%#x cbMemRange=%u\n", iRange, GCPhysStart, GCPhysEnd, cbMemRange)); rc = Elf64WriteProgHdr(hFile, PT_LOAD, PF_R, offMemRange, /* file offset to contents */ cbFileRange, /* size in core file */ cbMemRange, /* size in memory */ GCPhysStart, /* physical address */ &cbProgHdr); Assert(cbProgHdr == sizeof(Elf64_Phdr)); if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": Elf64WriteProgHdr failed for memory range(%u) cbFileRange=%u cbMemRange=%u rc=%Rrc\n", iRange, cbFileRange, cbMemRange, rc)); goto CoreWriteDone; } offMemRange += cbFileRange; } /* * Write the Core descriptor note header and data. */ rc = Elf64WriteNoteHdr(hFile, NT_VBOXCORE, s_pcszCoreVBoxCore, &CoreDescriptor, sizeof(CoreDescriptor), NULL /* pcbNoteHdr */); if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": Elf64WriteNoteHdr failed for Note '%s' rc=%Rrc\n", s_pcszCoreVBoxCore, rc)); goto CoreWriteDone; } /* * Write the CPU context note headers and data. */ for (uint32_t iCpu = 0; iCpu < pVM->cCpus; iCpu++) { PCPUMCTX pCpuCtx = &pVM->aCpus[iCpu].cpum.s.Guest; rc = Elf64WriteNoteHdr(hFile, NT_VBOXCPU, s_pcszCoreVBoxCpu, pCpuCtx, sizeof(CPUMCTX), NULL /* pcbNoteHdr */); if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": Elf64WriteNoteHdr failed for vCPU[%u] rc=%Rrc\n", iCpu, rc)); goto CoreWriteDone; } } /* * Write memory ranges. */ for (uint16_t iRange = 0; iRange < cMemRanges; iRange++) { RTGCPHYS GCPhysStart; RTGCPHYS GCPhysEnd; bool fIsMmio; rc = PGMR3PhysGetRange(pVM, iRange, &GCPhysStart, &GCPhysEnd, NULL /* pszDesc */, &fIsMmio); if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": PGMR3PhysGetRange(2) failed for iRange(%u) rc=%Rrc\n", iRange, rc)); goto CoreWriteDone; } if (fIsMmio) continue; /* * Write page-by-page of this memory range. */ uint64_t cbMemRange = GCPhysEnd - GCPhysStart + 1; uint64_t cPages = cbMemRange >> PAGE_SHIFT; for (uint64_t iPage = 0; iPage < cPages; iPage++) { const int cbBuf = PAGE_SIZE; void *pvBuf = MMR3HeapAlloc(pVM, MM_TAG_DBGF_CORE_WRITE, cbBuf); if (RT_UNLIKELY(!pvBuf)) { LogRel((DBGFLOG_NAME ": MMR3HeapAlloc failed. iRange=%u iPage=%u\n", iRange, iPage)); goto CoreWriteDone; } rc = PGMPhysRead(pVM, GCPhysStart, pvBuf, cbBuf); if (RT_FAILURE(rc)) { /* * For some reason this failed, write out a zero page instead. */ LogRel((DBGFLOG_NAME ": PGMPhysRead failed for iRange=%u iPage=%u. rc=%Rrc. Ignoring...\n", iRange, iPage, rc)); memset(pvBuf, 0, cbBuf); } rc = RTFileWrite(hFile, pvBuf, cbBuf, NULL /* all */); if (RT_FAILURE(rc)) { LogRel((DBGFLOG_NAME ": RTFileWrite failed. iRange=%u iPage=%u rc=%Rrc\n", iRange, iPage, rc)); MMR3HeapFree(pvBuf); goto CoreWriteDone; } MMR3HeapFree(pvBuf); } } CoreWriteDone: RTFileClose(hFile); return rc; } /** * Write core dump of the guest. * * @return VBox status code. * @param pVM The VM handle. * @param pszDumpPath The path of the file to dump into, cannot be * NULL. * * @remarks The VM must be suspended before calling this function. */ VMMR3DECL(int) DBGFR3CoreWrite(PVM pVM, const char *pszDumpPath) { VM_ASSERT_VALID_EXT_RETURN(pVM, VERR_INVALID_VM_HANDLE); AssertReturn(pszDumpPath, VERR_INVALID_HANDLE); /* * Pass the core write request down to EMT rendezvous which makes sure * other EMTs, if any, are not running. IO threads could still be running * but we don't care about them. */ DBGFCOREDATA CoreData; RT_ZERO(CoreData); CoreData.pszDumpPath = pszDumpPath; int rc = VMMR3EmtRendezvous(pVM, VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE, dbgfR3CoreWrite, &CoreData); if (RT_SUCCESS(rc)) LogRel((DBGFLOG_NAME ": Successfully wrote guest core dump %s\n", pszDumpPath)); else LogRel((DBGFLOG_NAME ": Failed to write guest core dump %s. rc=%Rrc\n", pszDumpPath, rc)); return rc; }