ref: 7d88d76bc42e2b3f3cabde82673af4107e951797
dir: /sys/src/cmd/vmx/exith.c/
#include <u.h> #include <libc.h> #include "dat.h" #include "fns.h" #include "x86.h" int persist = 1; typedef struct ExitInfo ExitInfo; struct ExitInfo { char *raw; char *name; uvlong qual; uvlong pa, va; u32int ilen, iinfo; }; char *x86reg[16] = { RAX, RCX, RDX, RBX, RSP, RBP, RSI, RDI, R8, R9, R10, R11, R12, R13, R14, R15 }; char *x86segreg[8] = { "cs", "ds", "es", "fs", "gs", "ss", }; static void skipinstr(ExitInfo *ei) { rset(RPC, rget(RPC) + ei->ilen); } static void iohandler(ExitInfo *ei) { int port, len, inc, isin; int asz, seg; uintptr addr; u32int val; uvlong vval; uintptr cx; static int seglook[8] = {SEGES, SEGCS, SEGSS, SEGDS, SEGFS, SEGGS}; TLB tlb; port = ei->qual >> 16 & 0xffff; len = (ei->qual & 7) + 1; isin = (ei->qual & 8) != 0; if((ei->qual & 1<<4) == 0){ /* not a string instruction */ if(isin){ val = io(1, port, 0, len); rsetsz(RAX, val, len); }else io(0, port, rget(RAX), len); skipinstr(ei); return; } if((rget("flags") & 0x400) != 0) inc = -len; else inc = len; switch(ei->iinfo >> 7 & 7){ case 0: asz = 2; break; default: asz = 4; break; case 2: asz = 8; break; } if((ei->qual & 1<<5) != 0) cx = rgetsz(RCX, asz); else cx = 1; addr = isin ? rget(RDI) : rget(RSI); if(isin) seg = SEGES; else seg = seglook[ei->iinfo >> 15 & 7]; memset(&tlb, 0, sizeof(TLB)); for(; cx > 0; cx--){ if(isin){ vval = io(1, port, 0, len); if(x86access(seg, addr, asz, &vval, len, ACCW, &tlb) < 0) goto err; }else{ if(x86access(seg, addr, asz, &vval, len, ACCR, &tlb) < 0) goto err; io(0, port, vval, len); } addr += inc; } skipinstr(ei); err: if((ei->qual & 1<<5) != 0) rsetsz(RCX, cx, asz); if(isin) rsetsz(RDI, addr, asz); else rsetsz(RSI, addr, asz); } static uvlong defaultmmio(int op, uvlong addr, uvlong val) { switch(op){ case MMIORD: vmerror("read from unmapped address %#ullx (pc=%#ullx)", addr, rget(RPC)); break; case MMIOWR: vmerror("write to unmapped address %#ullx (val=%#ullx,pc=%#ullx)", addr, val, rget(RPC)); break; } return 0; } static void eptfault(ExitInfo *ei) { if(x86step() > 0) skipinstr(ei); } typedef struct CPUID CPUID; struct CPUID { u32int ax, bx, cx, dx; }; static u32int cpuidmax; static u32int cpuidmaxext; static CPUID leaf1; static struct { uvlong miscen; }msr; static uchar _cpuid[] = { 0x5E, /* POP SI (PC) */ 0x5D, /* POP BP (CPUID&) */ 0x58, /* POP AX */ 0x59, /* POP CX */ 0x51, /* PUSH CX */ 0x50, /* PUSH AX */ 0x55, /* PUSH BP */ 0x56, /* PUSH SI */ 0x31, 0xDB, /* XOR BX, BX */ 0x31, 0xD2, /* XOR DX, DX */ 0x0F, 0xA2, /* CPUID */ 0x89, 0x45, 0x00, /* MOV AX, 0(BP) */ 0x89, 0x5d, 0x04, /* MOV BX, 4(BP) */ 0x89, 0x4d, 0x08, /* MOV CX, 8(BP) */ 0x89, 0x55, 0x0C, /* MOV DX, 12(BP) */ 0xC3, /* RET */ }; static CPUID (*getcpuid)(ulong ax, ulong cx) = (CPUID(*)(ulong, ulong)) _cpuid; void cpuidinit(void) { CPUID r; int f; if(sizeof(uintptr) == 8) /* patch out POP BP -> POP AX */ _cpuid[1] = 0x58; segflush(_cpuid, sizeof(_cpuid)); r = getcpuid(0, 0); cpuidmax = r.ax; r = getcpuid(0x80000000, 0); cpuidmaxext = r.ax; leaf1 = getcpuid(1, 0); memset(&msr, 0, sizeof(msr)); if((f = open("/dev/msr", OREAD)) >= 0){ pread(f, &msr.miscen, 8, 0x1a0); msr.miscen &= 1<<0; /* fast strings */ close(f); } } static int xsavesz[] = { [1] = 512+64, [3] = 512+64, [7] = 512+64+256, }; static void cpuid(ExitInfo *ei) { u32int ax, bx, cx, dx; CPUID cp; ax = rget(RAX); cx = rget(RCX); bx = dx = 0; cp = getcpuid(ax, cx); switch(ax){ case 0x00: /* highest register & GenuineIntel */ ax = MIN(cpuidmax, 0x18); bx = cp.bx; dx = cp.dx; cx = cp.cx; break; case 0x01: /* features */ ax = cp.ax; bx = cp.bx & 0xffff; /* some features removed, hypervisor added */ cx = cp.cx & 0x76de3217 | 0x80000000UL; dx = cp.dx & 0x0f8aa579; if(leaf1.cx & 1<<27){ if(rget("cr4real") & Cr4Osxsave) cx |= 1<<27; }else{ cx &= ~0x1c000000; } break; case 0x02: goto literal; /* cache stuff */ case 0x03: goto zero; /* processor serial number */ case 0x04: goto literal; /* cache stuff */ case 0x05: goto zero; /* monitor/mwait */ case 0x06: goto zero; /* thermal management */ case 0x07: /* more features */ if(cx == 0){ ax = 0; bx = cp.bx & 0x2369; cx = 0; if((leaf1.cx & 1<<27) == 0) bx &= ~0xdc230020; }else{ goto zero; } break; case 0x08: goto zero; case 0x09: goto literal; /* direct cache access */ case 0x0a: goto zero; /* performance counters */ case 0x0b: goto zero; /* extended topology */ case 0x0c: goto zero; case 0x0d: /* extended state */ if((leaf1.cx & 1<<27) == 0) goto zero; if(cx == 0){ /* main leaf */ ax = cp.ax & 7; /* x87, sse, avx */ bx = xsavesz[rget("xcr0")]; /* current xsave size */ cx = xsavesz[ax]; /* max xsave size */ }else if(cx == 1){ /* sub leaf */ ax = cp.ax & 7; /* xsaveopt, xsavec, xgetbv1 */ bx = xsavesz[rget("xcr0")]; cx = 0; }else if(cx == 2){ ax = xsavesz[7] - xsavesz[3]; bx = xsavesz[3]; cx = 0; }else{ goto zero; } break; case 0x0f: goto zero; /* RDT */ case 0x10: goto zero; /* RDT */ case 0x12: goto zero; /* SGX */ case 0x14: goto zero; /* PT */ case 0x15: goto zero; /* TSC */ case 0x16: goto zero; /* cpu clock */ case 0x17: goto zero; /* SoC */ case 0x18: goto literal; /* pages, tlb */ case 0x40000000: /* hypervisor */ ax = 0; bx = 0x4b4d564b; /* act as KVM */ cx = 0x564b4d56; dx = 0x4d; break; case 0x80000000: /* highest register */ ax = MIN(cpuidmaxext, 0x80000008); cx = 0; break; case 0x80000001: /* signature & ext features */ ax = cp.ax; cx = cp.cx & 0x121; if(sizeof(uintptr) == 8) dx = cp.dx & 0x24100800; else dx = cp.dx & 0x04100000; break; case 0x80000002: goto literal; /* brand string */ case 0x80000003: goto literal; /* brand string */ case 0x80000004: goto literal; /* brand string */ case 0x80000005: goto zero; /* reserved */ case 0x80000006: goto literal; /* cache info */ case 0x80000007: goto zero; /* invariant tsc */ case 0x80000008: goto literal; /* address bits */ literal: ax = cp.ax; bx = cp.bx; cx = cp.cx; dx = cp.dx; break; default: if((ax & 0xf0000000) != 0x40000000) vmdebug("unknown cpuid field eax=%#ux", ax); zero: ax = cx = 0; break; } rset(RAX, ax); rset(RBX, bx); rset(RCX, cx); rset(RDX, dx); skipinstr(ei); } static void rdwrmsr(ExitInfo *ei) { u32int cx; u64int val; int rd; rd = ei->name[1] == 'r'; cx = rget(RCX); val = (uvlong)rget(RDX) << 32 | rget(RAX); switch(cx){ case 0x277: if(rd) val = rget("pat"); else rset("pat", val); break; case 0x8B: val = 0; break; /* microcode update */ case 0x1A0: /* IA32_MISC_ENABLE */ if(rd) val = msr.miscen; break; default: if(rd){ vmdebug("read from unknown MSR %#ux ignored", cx); val = 0; }else vmdebug("write to unknown MSR %#ux ignored (val=%#ullx)", cx, val); break; } if(rd){ rset(RAX, (u32int)val); rset(RDX, (u32int)(val >> 32)); } skipinstr(ei); } static void movdr(ExitInfo *ei) { static char *dr[8] = { "dr0", "dr1", "dr2", "dr3", nil, nil, "dr6", "dr7" }; int q; q = ei->qual; if((q & 6) == 4){ postexc("#gp", 0); return; } if((q & 16) != 0) rset(x86reg[q >> 8 & 15], rget(dr[q & 7])); else rset(dr[q & 7], rget(x86reg[q >> 8 & 15])); skipinstr(ei); } static void movcr(ExitInfo *ei) { u32int q; q = ei->qual; switch(q & 15){ case 0: switch(q >> 4 & 3){ case 0: vmdebug("illegal CR0 write, value %#ux", (u32int)rget(x86reg[q >> 8 & 15])); rset("cr0real", rget(x86reg[q >> 8 & 15])); skipinstr(ei); break; case 1: vmerror("shouldn't happen: trap on MOV from CR0"); rset(x86reg[q >> 8 & 15], rget("cr0fake")); skipinstr(ei); break; case 2: vmerror("shouldn't happen: trap on CLTS"); rset("cr0real", rget("cr0real") & ~8); skipinstr(ei); break; case 3: vmerror("LMSW handler unimplemented"); postexc("#ud", NOERRC); } break; case 4: switch(q >> 4 & 3){ case 0: vmdebug("illegal CR4 write, value %#ux", (u32int)rget(x86reg[q >> 8 & 15])); rset("cr4real", rget(x86reg[q >> 8 & 15])); skipinstr(ei); break; case 1: vmerror("shouldn't happen: trap on MOV from CR4"); rset(x86reg[q >> 8 & 15], rget("cr3fake")); skipinstr(ei); break; default: vmerror("unknown CR4 operation %d", q); postexc("#ud", NOERRC); } break; default: vmerror("access to unknown control register CR%ud", q & 15); postexc("#ud", NOERRC); } } static void dbgexc(ExitInfo *ei) { rset("dr6", rget("dr6") | ei->qual); postexc("#db", NOERRC); } static void hlt(ExitInfo *ei) { if(irqactive < 0) state = VMHALT; skipinstr(ei); } static void irqackhand(ExitInfo *ei) { irqack(ei->qual); } static void xsetbv(ExitInfo *ei) { uvlong v; /* this should also #ud if LOCK prefix is used */ v = rget(RAX)&0xffffffff | rget(RDX)<<32; if(rget(RCX) & 0xffffffff) postexc("#gp", 0); else if(v != 1 && v != 3 && v != 7) postexc("#gp", 0); else if((leaf1.cx & 1<<26) == 0 || (rget("cr4real") & Cr4Osxsave) == 0) postexc("#ud", NOERRC); else{ rset("xcr0", v); skipinstr(ei); } } typedef struct ExitType ExitType; struct ExitType { char *name; void (*f)(ExitInfo *); }; static ExitType etypes[] = { {"io", iohandler}, {".cpuid", cpuid}, {".hlt", hlt}, {"eptfault", eptfault}, {"*ack", irqackhand}, {".rdmsr", rdwrmsr}, {".wrmsr", rdwrmsr}, {".movdr", movdr}, {"#db", dbgexc}, {"movcr", movcr}, {".xsetbv", xsetbv}, }; void processexit(char *msg) { static char msgc[1024]; char *f[32]; int nf; ExitType *et; int i; ExitInfo ei; extern int getexit; strcpy(msgc, msg); nf = tokenize(msgc, f, nelem(f)); if(nf < 2) sysfatal("invalid wait message: %s", msg); memset(&ei, 0, sizeof(ei)); ei.raw = msg; ei.name = f[0]; ei.qual = strtoull(f[1], nil, 0); for(i = 2; i < nf; i += 2){ if(strcmp(f[i], "pc") == 0) rpoke(RPC, strtoull(f[i+1], nil, 0), 1); else if(strcmp(f[i], "sp") == 0) rpoke(RSP, strtoull(f[i+1], nil, 0), 1); else if(strcmp(f[i], "ax") == 0) rpoke(RAX, strtoull(f[i+1], nil, 0), 1); else if(strcmp(f[i], "ilen") == 0) ei.ilen = strtoul(f[i+1], nil, 0); else if(strcmp(f[i], "iinfo") == 0) ei.iinfo = strtoul(f[i+1], nil, 0); else if(strcmp(f[i], "pa") == 0) ei.pa = strtoull(f[i+1], nil, 0); else if(strcmp(f[i], "va") == 0) ei.va = strtoull(f[i+1], nil, 0); } if(*f[0] == '*') getexit++; for(et = etypes; et < etypes + nelem(etypes); et++) if(strcmp(et->name, f[0]) == 0){ et->f(&ei); return; } if(*f[0] == '.'){ vmerror("vmx: unknown instruction %s", f[0]+1); postexc("#ud", NOERRC); return; } if(*f[0] == '*'){ vmerror("vmx: unknown notification %s", f[0]+1); return; } if(persist){ vmerror("unknown exit: %s", msg); state = VMDEAD; }else sysfatal("unknown exit: %s", msg); }