From d3a519ef0c810fb24a7d299c90f9a2d88e500360 Mon Sep 17 00:00:00 2001 From: Ali Saidi Date: Wed, 2 Jun 2010 12:58:17 -0500 Subject: ARM: Fixup native trace support and add some v7/recent stack code --- util/statetrace/arch/tracechild_arm.cc | 49 +++++++++++++++++++++++++++------- util/statetrace/arch/tracechild_arm.hh | 21 ++++++++++++--- 2 files changed, 56 insertions(+), 14 deletions(-) (limited to 'util/statetrace/arch') diff --git a/util/statetrace/arch/tracechild_arm.cc b/util/statetrace/arch/tracechild_arm.cc index b52c0694a..b03cb208b 100644 --- a/util/statetrace/arch/tracechild_arm.cc +++ b/util/statetrace/arch/tracechild_arm.cc @@ -1,4 +1,16 @@ /* + * Copyright (c) 2010 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * * Copyright (c) 2006-2009 The Regents of The University of Michigan * All rights reserved. * @@ -33,6 +45,7 @@ #include #include #include +#include #include "tracechild_arm.hh" @@ -46,6 +59,8 @@ const char* ARMTraceChild::regNames[numregs] = { ARMTraceChild::ARMTraceChild() { + foundMvn = false; + for (int x = 0; x < numregs; x++) { memset(®s, 0, sizeof(regs)); memset(&oldregs, 0, sizeof(regs)); @@ -79,7 +94,7 @@ bool ARMTraceChild::sendState(int socket) toSend -= sent; messagePtr += sent; } - + return true; } @@ -97,7 +112,7 @@ bool ARMTraceChild::update(int pid) cerr << "update: " << strerror(errno) << endl; return false; } - + for(unsigned int x = 0; x < numregs; x++) regDiffSinceUpdate[x] = (getRegVal(x) != getOldRegVal(x)); return true; @@ -207,25 +222,39 @@ bool ARMTraceChild::step() uint32_t lr = getRegVal(14); uint32_t pc = getPC(); - uint32_t lrOp; + uint32_t lrOp, subsOp; + char obuf[128]; + bool patch = false; // Since ARM uses software breakpoints behind the scenes, they don't work // in read only areas like the page of routines provided by the kernel. The // link register generally holds the address the process wants to the // kernel to return to after it's done, so we'll install a software - // breakpoint there. If the lr happens to point to the next instruction - // we'll leave out our breakpoint to avoid an infinite loop. This isn't a - // fool proof strategy, but it should work well in all the reasonable - // scenarios I can think of right now. + // breakpoint there. + // + // Calls into the kernel user page always follow the form: + // MVN ... + // + // SUB PC, ... + // + // So we look for this pattern and set a breakpoint on the LR at the SUB + // instruction. - if (pc != lr) { + + subsOp = ptrace(PTRACE_PEEKDATA, pid, pc, 0); + if ((subsOp & 0xFFFF0FFF) == 0xe3e00a0f) + foundMvn = true; + + if (foundMvn && ((subsOp & 0xFFF0F000) == 0xe240f000)) { + foundMvn = false; lrOp = ptrace(PTRACE_PEEKDATA, pid, lr, 0); ptrace(PTRACE_POKEDATA, pid, lr, bkpt_inst); + patch = true; } ptraceSingleStep(); - if (pc != lr) { + + if (patch) ptrace(PTRACE_POKEDATA, pid, lr, lrOp); - } } diff --git a/util/statetrace/arch/tracechild_arm.hh b/util/statetrace/arch/tracechild_arm.hh index 9e1af6a8d..79eccd891 100644 --- a/util/statetrace/arch/tracechild_arm.hh +++ b/util/statetrace/arch/tracechild_arm.hh @@ -1,4 +1,16 @@ /* + * Copyright (c) 2010 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * * Copyright (c) 2009 The Regents of The University of Michigan * All rights reserved. * @@ -63,15 +75,16 @@ class ARMTraceChild : public TraceChild user_regs regs; user_regs oldregs; bool regDiffSinceUpdate[numregs]; - + bool foundMvn; + protected: bool update(int pid); - + public: ARMTraceChild(); bool sendState(int socket); - int getNumRegs() + int getNumRegs() { return numregs; } @@ -90,7 +103,7 @@ class ARMTraceChild : public TraceChild int64_t getRegVal(int num); int64_t getOldRegVal(int num); - + bool step(); uint64_t getPC() -- cgit v1.2.3