From 6398da1391ba9285aeb4fa3f4470f008bf730220 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Tue, 14 Jun 2016 09:40:15 +0100 Subject: [PATCH] MIPS: KVM: Trace guest register access emulation MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Trace emulation of guest access to various registers via MFC0/MTC0/DMFC0/DMTC0 instructions (coprocessor 0) and the RDHWR instruction (hardware registers exposed to userland), replacing some existing kvm_debug calls. Trace events are much more practical for this kind of debug output. Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Ralf Baechle Cc: Steven Rostedt Cc: Ingo Molnar Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini --- arch/mips/kvm/emulate.c | 31 +++++++++------ arch/mips/kvm/trace.h | 88 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 107 insertions(+), 12 deletions(-) diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c index ee0e61d2b6fb..2004e35288d0 100644 --- a/arch/mips/kvm/emulate.c +++ b/arch/mips/kvm/emulate.c @@ -979,7 +979,6 @@ enum emulation_result kvm_mips_emulate_CP0(u32 inst, u32 *opc, u32 cause, struct mips_coproc *cop0 = vcpu->arch.cop0; enum emulation_result er = EMULATE_DONE; u32 rt, rd, copz, sel, co_bit, op; - unsigned long pc = vcpu->arch.pc; unsigned long curr_pc; /* @@ -1046,20 +1045,27 @@ enum emulation_result kvm_mips_emulate_CP0(u32 inst, u32 *opc, u32 cause, #endif } - kvm_debug - ("[%#lx] MFCz[%d][%d], vcpu->arch.gprs[%d]: %#lx\n", - pc, rd, sel, rt, vcpu->arch.gprs[rt]); - + trace_kvm_hwr(vcpu, KVM_TRACE_MFC0, + KVM_TRACE_COP0(rd, sel), + vcpu->arch.gprs[rt]); break; case dmfc_op: vcpu->arch.gprs[rt] = cop0->reg[rd][sel]; + + trace_kvm_hwr(vcpu, KVM_TRACE_DMFC0, + KVM_TRACE_COP0(rd, sel), + vcpu->arch.gprs[rt]); break; case mtc_op: #ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS cop0->stat[rd][sel]++; #endif + trace_kvm_hwr(vcpu, KVM_TRACE_MTC0, + KVM_TRACE_COP0(rd, sel), + vcpu->arch.gprs[rt]); + if ((rd == MIPS_CP0_TLB_INDEX) && (vcpu->arch.gprs[rt] >= KVM_MIPS_GUEST_TLB_SIZE)) { @@ -1098,10 +1104,6 @@ enum emulation_result kvm_mips_emulate_CP0(u32 inst, u32 *opc, u32 cause, kvm_mips_write_count(vcpu, vcpu->arch.gprs[rt]); goto done; } else if ((rd == MIPS_CP0_COMPARE) && (sel == 0)) { - kvm_debug("[%#lx] MTCz, COMPARE %#lx <- %#lx\n", - pc, kvm_read_c0_guest_compare(cop0), - vcpu->arch.gprs[rt]); - /* If we are writing to COMPARE */ /* Clear pending timer interrupt, if any */ kvm_mips_write_compare(vcpu, @@ -1237,14 +1239,14 @@ enum emulation_result kvm_mips_emulate_CP0(u32 inst, u32 *opc, u32 cause, kvm_mips_trans_mtc0(inst, opc, vcpu); #endif } - - kvm_debug("[%#lx] MTCz, cop0->reg[%d][%d]: %#lx\n", pc, - rd, sel, cop0->reg[rd][sel]); break; case dmtc_op: kvm_err("!!!!!!![%#lx]dmtc_op: rt: %d, rd: %d, sel: %d!!!!!!\n", vcpu->arch.pc, rt, rd, sel); + trace_kvm_hwr(vcpu, KVM_TRACE_DMTC0, + KVM_TRACE_COP0(rd, sel), + vcpu->arch.gprs[rt]); er = EMULATE_FAIL; break; @@ -2307,6 +2309,8 @@ enum emulation_result kvm_mips_handle_ri(u32 cause, u32 *opc, int usermode = !KVM_GUEST_KERNEL_MODE(vcpu); int rd = (inst & RD) >> 11; int rt = (inst & RT) >> 16; + int sel = (inst >> 6) & 0x7; + /* If usermode, check RDHWR rd is allowed by guest HWREna */ if (usermode && !(kvm_read_c0_guest_hwrena(cop0) & BIT(rd))) { kvm_debug("RDHWR %#x disallowed by HWREna @ %p\n", @@ -2342,6 +2346,9 @@ enum emulation_result kvm_mips_handle_ri(u32 cause, u32 *opc, kvm_debug("RDHWR %#x not supported @ %p\n", rd, opc); goto emulate_ri; } + + trace_kvm_hwr(vcpu, KVM_TRACE_RDHWR, KVM_TRACE_HWR(rd, sel), + vcpu->arch.gprs[rt]); } else { kvm_debug("Emulate RI not supported @ %p: %#x\n", opc, inst); goto emulate_ri; diff --git a/arch/mips/kvm/trace.h b/arch/mips/kvm/trace.h index aec1c43f2b44..5d712ecb0734 100644 --- a/arch/mips/kvm/trace.h +++ b/arch/mips/kvm/trace.h @@ -124,6 +124,94 @@ TRACE_EVENT(kvm_exit, __entry->pc) ); +#define KVM_TRACE_MFC0 0 +#define KVM_TRACE_MTC0 1 +#define KVM_TRACE_DMFC0 2 +#define KVM_TRACE_DMTC0 3 +#define KVM_TRACE_RDHWR 4 + +#define KVM_TRACE_HWR_COP0 0 +#define KVM_TRACE_HWR_HWR 1 + +#define KVM_TRACE_COP0(REG, SEL) ((KVM_TRACE_HWR_COP0 << 8) | \ + ((REG) << 3) | (SEL)) +#define KVM_TRACE_HWR(REG, SEL) ((KVM_TRACE_HWR_HWR << 8) | \ + ((REG) << 3) | (SEL)) + +#define kvm_trace_symbol_hwr_ops \ + { KVM_TRACE_MFC0, "MFC0" }, \ + { KVM_TRACE_MTC0, "MTC0" }, \ + { KVM_TRACE_DMFC0, "DMFC0" }, \ + { KVM_TRACE_DMTC0, "DMTC0" }, \ + { KVM_TRACE_RDHWR, "RDHWR" } + +#define kvm_trace_symbol_hwr_cop \ + { KVM_TRACE_HWR_COP0, "COP0" }, \ + { KVM_TRACE_HWR_HWR, "HWR" } + +#define kvm_trace_symbol_hwr_regs \ + { KVM_TRACE_COP0( 0, 0), "Index" }, \ + { KVM_TRACE_COP0( 2, 0), "EntryLo0" }, \ + { KVM_TRACE_COP0( 3, 0), "EntryLo1" }, \ + { KVM_TRACE_COP0( 4, 0), "Context" }, \ + { KVM_TRACE_COP0( 4, 2), "UserLocal" }, \ + { KVM_TRACE_COP0( 5, 0), "PageMask" }, \ + { KVM_TRACE_COP0( 6, 0), "Wired" }, \ + { KVM_TRACE_COP0( 7, 0), "HWREna" }, \ + { KVM_TRACE_COP0( 8, 0), "BadVAddr" }, \ + { KVM_TRACE_COP0( 9, 0), "Count" }, \ + { KVM_TRACE_COP0(10, 0), "EntryHi" }, \ + { KVM_TRACE_COP0(11, 0), "Compare" }, \ + { KVM_TRACE_COP0(12, 0), "Status" }, \ + { KVM_TRACE_COP0(12, 1), "IntCtl" }, \ + { KVM_TRACE_COP0(12, 2), "SRSCtl" }, \ + { KVM_TRACE_COP0(13, 0), "Cause" }, \ + { KVM_TRACE_COP0(14, 0), "EPC" }, \ + { KVM_TRACE_COP0(15, 0), "PRId" }, \ + { KVM_TRACE_COP0(15, 1), "EBase" }, \ + { KVM_TRACE_COP0(16, 0), "Config" }, \ + { KVM_TRACE_COP0(16, 1), "Config1" }, \ + { KVM_TRACE_COP0(16, 2), "Config2" }, \ + { KVM_TRACE_COP0(16, 3), "Config3" }, \ + { KVM_TRACE_COP0(16, 4), "Config4" }, \ + { KVM_TRACE_COP0(16, 5), "Config5" }, \ + { KVM_TRACE_COP0(16, 7), "Config7" }, \ + { KVM_TRACE_COP0(26, 0), "ECC" }, \ + { KVM_TRACE_COP0(30, 0), "ErrorEPC" }, \ + { KVM_TRACE_HWR( 0, 0), "CPUNum" }, \ + { KVM_TRACE_HWR( 1, 0), "SYNCI_Step" }, \ + { KVM_TRACE_HWR( 2, 0), "CC" }, \ + { KVM_TRACE_HWR( 3, 0), "CCRes" }, \ + { KVM_TRACE_HWR(29, 0), "ULR" } + +TRACE_EVENT(kvm_hwr, + TP_PROTO(struct kvm_vcpu *vcpu, unsigned int op, unsigned int reg, + unsigned long val), + TP_ARGS(vcpu, op, reg, val), + TP_STRUCT__entry( + __field(unsigned long, val) + __field(u16, reg) + __field(u8, op) + ), + + TP_fast_assign( + __entry->val = val; + __entry->reg = reg; + __entry->op = op; + ), + + TP_printk("%s %s (%s:%u:%u) 0x%08lx", + __print_symbolic(__entry->op, + kvm_trace_symbol_hwr_ops), + __print_symbolic(__entry->reg, + kvm_trace_symbol_hwr_regs), + __print_symbolic(__entry->reg >> 8, + kvm_trace_symbol_hwr_cop), + (__entry->reg >> 3) & 0x1f, + __entry->reg & 0x7, + __entry->val) +); + #define KVM_TRACE_AUX_RESTORE 0 #define KVM_TRACE_AUX_SAVE 1 #define KVM_TRACE_AUX_ENABLE 2 -- 2.20.1