diff options
Diffstat (limited to 'arch/s390/kvm/guestdbg.c')
| -rw-r--r-- | arch/s390/kvm/guestdbg.c | 98 |
1 files changed, 89 insertions, 9 deletions
diff --git a/arch/s390/kvm/guestdbg.c b/arch/s390/kvm/guestdbg.c index a2077833ab01..23d9a4e12da1 100644 --- a/arch/s390/kvm/guestdbg.c +++ b/arch/s390/kvm/guestdbg.c @@ -436,6 +436,64 @@ exit_required: return 1; } +static int per_fetched_addr(struct kvm_vcpu *vcpu, unsigned long *addr) +{ + u8 exec_ilen = 0; + u16 opcode[3]; + int rc; + + if (vcpu->arch.sie_block->icptcode == ICPT_PROGI) { + /* PER address references the fetched or the execute instr */ + *addr = vcpu->arch.sie_block->peraddr; + /* + * Manually detect if we have an EXECUTE instruction. As + * instructions are always 2 byte aligned we can read the + * first two bytes unconditionally + */ + rc = read_guest_instr(vcpu, *addr, &opcode, 2); + if (rc) + return rc; + if (opcode[0] >> 8 == 0x44) + exec_ilen = 4; + if ((opcode[0] & 0xff0f) == 0xc600) + exec_ilen = 6; + } else { + /* instr was suppressed, calculate the responsible instr */ + *addr = __rewind_psw(vcpu->arch.sie_block->gpsw, + kvm_s390_get_ilen(vcpu)); + if (vcpu->arch.sie_block->icptstatus & 0x01) { + exec_ilen = (vcpu->arch.sie_block->icptstatus & 0x60) >> 4; + if (!exec_ilen) + exec_ilen = 4; + } + } + + if (exec_ilen) { + /* read the complete EXECUTE instr to detect the fetched addr */ + rc = read_guest_instr(vcpu, *addr, &opcode, exec_ilen); + if (rc) + return rc; + if (exec_ilen == 6) { + /* EXECUTE RELATIVE LONG - RIL-b format */ + s32 rl = *((s32 *) (opcode + 1)); + + /* rl is a _signed_ 32 bit value specifying halfwords */ + *addr += (u64)(s64) rl * 2; + } else { + /* EXECUTE - RX-a format */ + u32 base = (opcode[1] & 0xf000) >> 12; + u32 disp = opcode[1] & 0x0fff; + u32 index = opcode[0] & 0x000f; + + *addr = base ? vcpu->run->s.regs.gprs[base] : 0; + *addr += index ? vcpu->run->s.regs.gprs[index] : 0; + *addr += disp; + } + *addr = kvm_s390_logical_to_effective(vcpu, *addr); + } + return 0; +} + #define guest_per_enabled(vcpu) \ (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) @@ -449,6 +507,8 @@ int kvm_s390_handle_per_ifetch_icpt(struct kvm_vcpu *vcpu) .per_code = PER_CODE_IFETCH, .per_address = __rewind_psw(vcpu->arch.sie_block->gpsw, ilen), }; + unsigned long fetched_addr; + int rc; /* * The PSW points to the next instruction, therefore the intercepted @@ -465,21 +525,29 @@ int kvm_s390_handle_per_ifetch_icpt(struct kvm_vcpu *vcpu) !(vcpu->arch.sie_block->gcr[9] & PER_EVENT_IFETCH)) return 0; - if (in_addr_range(pgm_info.per_address, cr10, cr11)) + rc = per_fetched_addr(vcpu, &fetched_addr); + if (rc < 0) + return rc; + if (rc) + /* instruction-fetching exceptions */ + return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); + + if (in_addr_range(fetched_addr, cr10, cr11)) return kvm_s390_inject_prog_irq(vcpu, &pgm_info); return 0; } -static void filter_guest_per_event(struct kvm_vcpu *vcpu) +static int filter_guest_per_event(struct kvm_vcpu *vcpu) { const u8 perc = vcpu->arch.sie_block->perc; - u64 peraddr = vcpu->arch.sie_block->peraddr; u64 addr = vcpu->arch.sie_block->gpsw.addr; u64 cr9 = vcpu->arch.sie_block->gcr[9]; u64 cr10 = vcpu->arch.sie_block->gcr[10]; u64 cr11 = vcpu->arch.sie_block->gcr[11]; /* filter all events, demanded by the guest */ u8 guest_perc = perc & (cr9 >> 24) & PER_CODE_MASK; + unsigned long fetched_addr; + int rc; if (!guest_per_enabled(vcpu)) guest_perc = 0; @@ -491,9 +559,17 @@ static void filter_guest_per_event(struct kvm_vcpu *vcpu) guest_perc &= ~PER_CODE_BRANCH; /* filter "instruction-fetching" events */ - if (guest_perc & PER_CODE_IFETCH && - !in_addr_range(peraddr, cr10, cr11)) - guest_perc &= ~PER_CODE_IFETCH; + if (guest_perc & PER_CODE_IFETCH) { + rc = per_fetched_addr(vcpu, &fetched_addr); + if (rc < 0) + return rc; + /* + * Don't inject an irq on exceptions. This would make handling + * on icpt code 8 very complex (as PSW was already rewound). + */ + if (rc || !in_addr_range(fetched_addr, cr10, cr11)) + guest_perc &= ~PER_CODE_IFETCH; + } /* All other PER events will be given to the guest */ /* TODO: Check altered address/address space */ @@ -502,6 +578,7 @@ static void filter_guest_per_event(struct kvm_vcpu *vcpu) if (!guest_perc) vcpu->arch.sie_block->iprcc &= ~PGM_PER; + return 0; } #define pssec(vcpu) (vcpu->arch.sie_block->gcr[1] & _ASCE_SPACE_SWITCH) @@ -509,15 +586,17 @@ static void filter_guest_per_event(struct kvm_vcpu *vcpu) #define old_ssec(vcpu) ((vcpu->arch.sie_block->tecmc >> 31) & 0x1) #define old_as_is_home(vcpu) !(vcpu->arch.sie_block->tecmc & 0xffff) -void kvm_s390_handle_per_event(struct kvm_vcpu *vcpu) +int kvm_s390_handle_per_event(struct kvm_vcpu *vcpu) { - int new_as; + int rc, new_as; if (debug_exit_required(vcpu, vcpu->arch.sie_block->perc, vcpu->arch.sie_block->peraddr)) vcpu->guest_debug |= KVM_GUESTDBG_EXIT_PENDING; - filter_guest_per_event(vcpu); + rc = filter_guest_per_event(vcpu); + if (rc) + return rc; /* * Only RP, SAC, SACF, PT, PTI, PR, PC instructions can trigger @@ -546,4 +625,5 @@ void kvm_s390_handle_per_event(struct kvm_vcpu *vcpu) (pssec(vcpu) || old_ssec(vcpu))) vcpu->arch.sie_block->iprcc = PGM_SPACE_SWITCH; } + return 0; } |