/* $Id: DBGFStack.cpp 5999 2007-12-07 15:05:06Z vboxsync $ */ /** @file * VMM DBGF - Debugger Facility, Call Stack Analyser. */ /* * Copyright (C) 2006-2007 innotek GmbH * * 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. */ /******************************************************************************* * Header Files * *******************************************************************************/ #define LOG_GROUP LOG_GROUP_DBGF #include #include #include "DBGFInternal.h" #include #include #include #include #include #include #include /** * Read stack memory. */ DECLINLINE(int) dbgfR3Read(PVM pVM, void *pvBuf, RTGCUINTPTR GCPtr, size_t cb, size_t *pcbRead) { int rc = MMR3ReadGCVirt(pVM, pvBuf, GCPtr, cb); if (VBOX_FAILURE(rc)) { size_t cbRead; for (cbRead = 0; cbRead < cb; cbRead++) { rc = MMR3ReadGCVirt(pVM, (uint8_t *)pvBuf + cbRead, GCPtr + cbRead, 1); if (VBOX_FAILURE(rc)) break; } if (cbRead) rc = VINF_SUCCESS; memset((char *)pvBuf + cbRead, 0, cb - cbRead); *pcbRead = cbRead; } else *pcbRead = cb; return rc; } /** * Internal worker routine. * * On x86 the typical stack frame layout is like this: * .. .. * 16 parameter 2 * 12 parameter 1 * 8 parameter 0 * 4 return address * 0 old ebp; current ebp points here */ static int dbgfR3StackWalk(PVM pVM, PDBGFSTACKFRAME pFrame) { /* * Stop if we got a read error in the previous run. */ if (pFrame->fFlags & DBGFSTACKFRAME_FLAGS_LAST) return VERR_NO_MORE_FILES; /* * Read the raw frame data. */ const DBGFADDRESS AddrOldPC = pFrame->AddrPC; const unsigned cbRetAddr = DBGFReturnTypeSize(pFrame->enmReturnType); unsigned cbStackItem; switch (AddrOldPC.fFlags & DBGFADDRESS_FLAGS_TYPE_MASK) { case DBGFADDRESS_FLAGS_FAR16: cbStackItem = 2; break; case DBGFADDRESS_FLAGS_FAR32: cbStackItem = 4; break; case DBGFADDRESS_FLAGS_FAR64: cbStackItem = 8; break; default: cbStackItem = 4; break; /// @todo 64-bit guests. } union { uint64_t *pu64; uint32_t *pu32; uint16_t *pu16; uint8_t *pb; void *pv; } u, uRet, uArgs, uBp; size_t cbRead = cbRetAddr + cbStackItem + sizeof(pFrame->Args); u.pv = alloca(cbRead); uBp = u; uRet.pb = u.pb + cbStackItem; uArgs.pb = u.pb + cbStackItem + cbRetAddr; Assert(DBGFADDRESS_IS_VALID(&pFrame->AddrFrame)); int rc = dbgfR3Read(pVM, u.pv, pFrame->fFlags & DBGFSTACKFRAME_FLAGS_ALL_VALID ? pFrame->AddrReturnFrame.FlatPtr : pFrame->AddrFrame.FlatPtr, cbRead, &cbRead); if ( VBOX_FAILURE(rc) || cbRead < cbRetAddr + cbStackItem) pFrame->fFlags |= DBGFSTACKFRAME_FLAGS_LAST; /* * The first step is taken in a different way than the others. */ if (!(pFrame->fFlags & DBGFSTACKFRAME_FLAGS_ALL_VALID)) { pFrame->fFlags |= DBGFSTACKFRAME_FLAGS_ALL_VALID; pFrame->iFrame = 0; /* Current PC - set by caller, just find symbol & line. */ if (DBGFADDRESS_IS_VALID(&pFrame->AddrPC)) { pFrame->pSymPC = DBGFR3SymbolByAddrAlloc(pVM, pFrame->AddrPC.FlatPtr, NULL); pFrame->pLinePC = DBGFR3LineByAddrAlloc(pVM, pFrame->AddrPC.FlatPtr, NULL); } } else /* 2nd and subsequent steps */ { /* frame, pc and stack is taken from the existing frames return members. */ pFrame->AddrFrame = pFrame->AddrReturnFrame; pFrame->AddrPC = pFrame->AddrReturnPC; pFrame->pSymPC = pFrame->pSymReturnPC; pFrame->pLinePC = pFrame->pLineReturnPC; /* increment the frame number. */ pFrame->iFrame++; } /* * Return Frame address. */ pFrame->AddrReturnFrame = pFrame->AddrFrame; switch (cbStackItem) { case 2: pFrame->AddrReturnFrame.off = *uBp.pu16; break; case 4: pFrame->AddrReturnFrame.off = *uBp.pu32; break; case 8: pFrame->AddrReturnFrame.off = *uBp.pu64; break; default: AssertMsgFailed(("cbStackItem=%d\n", cbStackItem)); return VERR_INTERNAL_ERROR; } pFrame->AddrReturnFrame.FlatPtr += pFrame->AddrReturnFrame.off - pFrame->AddrFrame.off; /* * Return PC and Stack Addresses. */ /** @todo AddrReturnStack is not correct for stdcall and pascal. (requires scope info) */ pFrame->AddrReturnStack = pFrame->AddrFrame; pFrame->AddrReturnStack.off += cbStackItem + cbRetAddr; pFrame->AddrReturnStack.FlatPtr += cbStackItem + cbRetAddr; pFrame->AddrReturnPC = pFrame->AddrPC; switch (pFrame->enmReturnType) { case DBGFRETURNTYPE_NEAR16: if (DBGFADDRESS_IS_VALID(&pFrame->AddrReturnPC)) { pFrame->AddrReturnPC.FlatPtr += *uRet.pu16 - pFrame->AddrReturnPC.off; pFrame->AddrReturnPC.off = *uRet.pu16; } else DBGFR3AddrFromFlat(pVM, &pFrame->AddrReturnPC, *uRet.pu16); break; case DBGFRETURNTYPE_NEAR32: if (DBGFADDRESS_IS_VALID(&pFrame->AddrReturnPC)) { pFrame->AddrReturnPC.FlatPtr += *uRet.pu32 - pFrame->AddrReturnPC.off; pFrame->AddrReturnPC.off = *uRet.pu32; } else DBGFR3AddrFromFlat(pVM, &pFrame->AddrReturnPC, *uRet.pu32); break; case DBGFRETURNTYPE_NEAR64: if (DBGFADDRESS_IS_VALID(&pFrame->AddrReturnPC)) { pFrame->AddrReturnPC.FlatPtr += *uRet.pu64 - pFrame->AddrReturnPC.off; pFrame->AddrReturnPC.off = *uRet.pu64; } else DBGFR3AddrFromFlat(pVM, &pFrame->AddrReturnPC, *uRet.pu64); break; case DBGFRETURNTYPE_FAR16: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[1], uRet.pu16[0]); break; case DBGFRETURNTYPE_FAR32: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[2], uRet.pu32[0]); break; case DBGFRETURNTYPE_FAR64: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[4], uRet.pu64[0]); break; case DBGFRETURNTYPE_IRET16: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[1], uRet.pu16[0]); break; case DBGFRETURNTYPE_IRET32: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[2], uRet.pu32[0]); break; case DBGFRETURNTYPE_IRET32_PRIV: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[2], uRet.pu32[0]); break; case DBGFRETURNTYPE_IRET32_V86: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[2], uRet.pu32[0]); break; case DBGFRETURNTYPE_IRET64: DBGFR3AddrFromSelOff(pVM, &pFrame->AddrReturnPC, uRet.pu16[4], uRet.pu64[0]); break; default: AssertMsgFailed(("enmReturnType=%d\n", pFrame->enmReturnType)); return VERR_INVALID_PARAMETER; } pFrame->pSymReturnPC = DBGFR3SymbolByAddrAlloc(pVM, pFrame->AddrReturnPC.FlatPtr, NULL); pFrame->pLineReturnPC = DBGFR3LineByAddrAlloc(pVM, pFrame->AddrReturnPC.FlatPtr, NULL); /* * The arguments. */ memcpy(&pFrame->Args, uArgs.pv, sizeof(pFrame->Args)); return VINF_SUCCESS; } /** * Walks the entire stack allocating memory as we walk. */ static DECLCALLBACK(int) dbgfR3StackWalkCtxFull(PVM pVM, PDBGFSTACKFRAME pFrame, PCCPUMCTXCORE pCtxCore, bool fGuest) { pFrame->pNext = NULL; pFrame->pFirst = NULL; /* alloc first frame. */ PDBGFSTACKFRAME pCur = (PDBGFSTACKFRAME)MMR3HeapAllocZ(pVM, MM_TAG_DBGF_STACK, sizeof(*pCur)); if (!pCur) return VERR_NO_MEMORY; /* copy input frame */ pCur->AddrFrame = pFrame->AddrFrame; pCur->AddrStack = pFrame->AddrStack; pCur->AddrPC = pFrame->AddrPC; pCur->enmReturnType = pFrame->enmReturnType; pCur->pNext = NULL; pCur->pFirst = pCur; int rc = VINF_SUCCESS; if (!DBGFADDRESS_IS_VALID(&pCur->AddrPC)) rc = DBGFR3AddrFromSelOff(pVM, &pCur->AddrPC, pCtxCore->cs, pCtxCore->eip); if (VBOX_SUCCESS(rc) /*&& pCur->enmReturnType == DBGFRETURNTYPE_INVALID*/) { switch (pCur->AddrPC.fFlags & DBGFADDRESS_FLAGS_TYPE_MASK) { case DBGFADDRESS_FLAGS_FAR16: pCur->enmReturnType = DBGFRETURNTYPE_NEAR16; break; case DBGFADDRESS_FLAGS_FAR32: pCur->enmReturnType = DBGFRETURNTYPE_NEAR32; break; case DBGFADDRESS_FLAGS_FAR64: pCur->enmReturnType = DBGFRETURNTYPE_NEAR64; break; default: pCur->enmReturnType = DBGFRETURNTYPE_NEAR32; break; /// @todo 64-bit guests } } uint64_t u64Mask = UINT64_MAX; if (VBOX_SUCCESS(rc) && DBGFADDRESS_IS_FAR16(&pCur->AddrPC) && fGuest) u64Mask = UINT16_MAX; if (VBOX_SUCCESS(rc) && !DBGFADDRESS_IS_VALID(&pCur->AddrStack)) rc = DBGFR3AddrFromSelOff(pVM, &pCur->AddrStack, pCtxCore->ss, pCtxCore->esp & u64Mask); if (VBOX_SUCCESS(rc) && !DBGFADDRESS_IS_VALID(&pCur->AddrFrame)) rc = DBGFR3AddrFromSelOff(pVM, &pCur->AddrFrame, pCtxCore->ss, pCtxCore->ebp & u64Mask); /* * The first frame. */ if (VBOX_SUCCESS(rc)) rc = dbgfR3StackWalk(pVM, pCur); if (VBOX_FAILURE(rc)) { DBGFR3StackWalkEnd(pVM, pCur); return rc; } /* * The other frames. */ DBGFSTACKFRAME Next = *pCur; while (!(pCur->fFlags & (DBGFSTACKFRAME_FLAGS_LAST | DBGFSTACKFRAME_FLAGS_MAX_DEPTH | DBGFSTACKFRAME_FLAGS_LOOP))) { /* try walk. */ rc = dbgfR3StackWalk(pVM, &Next); if (VBOX_FAILURE(rc)) break; /* add the next frame to the chain. */ PDBGFSTACKFRAME pNext = (PDBGFSTACKFRAME)MMR3HeapAlloc(pVM, MM_TAG_DBGF_STACK, sizeof(*pNext)); if (!pNext) { DBGFR3StackWalkEnd(pVM, pCur); return VERR_NO_MEMORY; } *pNext = Next; pCur = pCur->pNext = pNext; Assert(pCur->pNext == NULL); /* check for loop */ for (PDBGFSTACKFRAME pLoop = pCur->pFirst; pLoop && pLoop != pCur; pLoop = pLoop->pNext) if (pLoop->AddrFrame.FlatPtr == pCur->AddrFrame.FlatPtr) { pCur->fFlags |= DBGFSTACKFRAME_FLAGS_LOOP; break; } /* check for insane recursion */ if (pCur->iFrame >= 2048) pCur->fFlags |= DBGFSTACKFRAME_FLAGS_MAX_DEPTH; } *pFrame = *pCur->pFirst; return rc; } /** * Begins a stack walk. * This will construct and obtain the first frame. * * @returns VINF_SUCCESS on success. * @returns VERR_NO_MEMORY if we're out of memory. * @param pVM The VM handle. * @param pFrame The stack frame info structure. * On input this structure must be memset to zero. * If wanted, the AddrPC, AddrStack and AddrFrame fields may be set * to valid addresses after memsetting it. Any of those fields not set * will be fetched from the guest CPU state. * On output the structure will contain all the information we were able to * obtain about the stack frame. */ DBGFR3DECL(int) DBGFR3StackWalkBeginGuest(PVM pVM, PDBGFSTACKFRAME pFrame) { pFrame->pFirst = NULL; pFrame->pNext = NULL; PVMREQ pReq; int rc = VMR3ReqCall(pVM, &pReq, RT_INDEFINITE_WAIT, (PFNRT)dbgfR3StackWalkCtxFull, 4, pVM, pFrame, CPUMGetGuestCtxCore(pVM), true); if (VBOX_SUCCESS(rc)) rc = pReq->iStatus; VMR3ReqFree(pReq); return rc; } /** * Begins a stack walk. * This will construct and obtain the first frame. * * @returns VINF_SUCCESS on success. * @returns VERR_NO_MEMORY if we're out of memory. * @param pVM The VM handle. * @param pFrame The stack frame info structure. * On input this structure must be memset to zero. * If wanted, the AddrPC, AddrStack and AddrFrame fields may be set * to valid addresses after memsetting it. Any of those fields not set * will be fetched from the hypervisor CPU state. * On output the structure will contain all the information we were able to * obtain about the stack frame. */ DBGFR3DECL(int) DBGFR3StackWalkBeginHyper(PVM pVM, PDBGFSTACKFRAME pFrame) { pFrame->pFirst = NULL; pFrame->pNext = NULL; PVMREQ pReq; int rc = VMR3ReqCall(pVM, &pReq, RT_INDEFINITE_WAIT, (PFNRT)dbgfR3StackWalkCtxFull, 4, pVM, pFrame, CPUMGetHyperCtxCore(pVM), 4); if (VBOX_SUCCESS(rc)) rc = pReq->iStatus; VMR3ReqFree(pReq); return rc; } /** * Gets the next stack frame. * * @returns VINF_SUCCESS * @returns VERR_NO_MORE_FILES if not more stack frames. * @param pVM The VM handle. * @param pFrame Pointer to the current frame on input, content is replaced with the next frame on successful return. */ DBGFR3DECL(int) DBGFR3StackWalkNext(PVM pVM, PDBGFSTACKFRAME pFrame) { if (pFrame->pNext) { *pFrame = *pFrame->pNext; return VINF_SUCCESS; } return VERR_NO_MORE_FILES; } /** * Ends a stack walk process. * * This *must* be called after a successful first call to any of the stack * walker functions. If not called we will leak memory or other resources. * * @param pVM The VM handle. * @param pFrame The stackframe as returned by the last stack walk call. */ DBGFR3DECL(void) DBGFR3StackWalkEnd(PVM pVM, PDBGFSTACKFRAME pFrame) { if (!pFrame || !pFrame->pFirst) return; pFrame = pFrame->pFirst; while (pFrame) { PDBGFSTACKFRAME pCur = pFrame; pFrame = pCur->pNext; if (pFrame) { if (pCur->pSymReturnPC == pFrame->pSymPC) pFrame->pSymPC = NULL; if (pCur->pSymReturnPC == pFrame->pSymReturnPC) pFrame->pSymReturnPC = NULL; if (pCur->pSymPC == pFrame->pSymPC) pFrame->pSymPC = NULL; if (pCur->pSymPC == pFrame->pSymReturnPC) pFrame->pSymReturnPC = NULL; if (pCur->pLineReturnPC == pFrame->pLinePC) pFrame->pLinePC = NULL; if (pCur->pLineReturnPC == pFrame->pLineReturnPC) pFrame->pLineReturnPC = NULL; if (pCur->pLinePC == pFrame->pLinePC) pFrame->pLinePC = NULL; if (pCur->pLinePC == pFrame->pLineReturnPC) pFrame->pLineReturnPC = NULL; } DBGFR3SymbolFree(pCur->pSymPC); DBGFR3SymbolFree(pCur->pSymReturnPC); DBGFR3LineFree(pCur->pLinePC); DBGFR3LineFree(pCur->pLineReturnPC); pCur->pNext = NULL; pCur->pFirst = NULL; pCur->fFlags = 0; MMR3HeapFree(pCur); } }