diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/s390/s390mach.c | 321 | ||||
-rw-r--r-- | drivers/s390/s390mach.h | 35 |
2 files changed, 317 insertions, 39 deletions
diff --git a/drivers/s390/s390mach.c b/drivers/s390/s390mach.c index ffa996c..5bb255e 100644 --- a/drivers/s390/s390mach.c +++ b/drivers/s390/s390mach.c @@ -31,14 +31,14 @@ extern void css_reiterate_subchannels(void); extern struct workqueue_struct *slow_path_wq; extern struct work_struct slow_path_work; -static void +static NORET_TYPE void s390_handle_damage(char *msg) { - printk(KERN_EMERG "%s\n", msg); #ifdef CONFIG_SMP smp_send_stop(); #endif disabled_wait((unsigned long) __builtin_return_address(0)); + for(;;); } /* @@ -122,40 +122,39 @@ repeat: return 0; } +struct mcck_struct { + int kill_task; + int channel_report; + int warning; + unsigned long long mcck_code; +}; + +static DEFINE_PER_CPU(struct mcck_struct, cpu_mcck); + /* - * machine check handler. + * Main machine check handler function. Will be called with interrupts enabled + * or disabled and machine checks enabled or disabled. */ void -s390_do_machine_check(void) +s390_handle_mcck(void) { - struct mci *mci; - - mci = (struct mci *) &S390_lowcore.mcck_interruption_code; + unsigned long flags; + struct mcck_struct mcck; - if (mci->sd) /* system damage */ - s390_handle_damage("received system damage machine check\n"); + /* + * Disable machine checks and get the current state of accumulated + * machine checks. Afterwards delete the old state and enable machine + * checks again. + */ + local_irq_save(flags); + local_mcck_disable(); + mcck = __get_cpu_var(cpu_mcck); + memset(&__get_cpu_var(cpu_mcck), 0, sizeof(struct mcck_struct)); + clear_thread_flag(TIF_MCCK_PENDING); + local_mcck_enable(); + local_irq_restore(flags); - if (mci->pd) /* instruction processing damage */ - s390_handle_damage("received instruction processing " - "damage machine check\n"); - - if (mci->se) /* storage error uncorrected */ - s390_handle_damage("received storage error uncorrected " - "machine check\n"); - - if (mci->sc) /* storage error corrected */ - printk(KERN_WARNING - "received storage error corrected machine check\n"); - - if (mci->ke) /* storage key-error uncorrected */ - s390_handle_damage("received storage key-error uncorrected " - "machine check\n"); - - if (mci->ds && mci->fa) /* storage degradation */ - s390_handle_damage("received storage degradation machine " - "check\n"); - - if (mci->cp) /* channel report word pending */ + if (mcck.channel_report) up(&m_sem); #ifdef CONFIG_MACHCHK_WARNING @@ -168,7 +167,7 @@ s390_do_machine_check(void) * On VM we only get one interrupt per virtally presented machinecheck. * Though one suffices, we may get one interrupt per (virtual) processor. */ - if (mci->w) { /* WARNING pending ? */ + if (mcck.warning) { /* WARNING pending ? */ static int mchchk_wng_posted = 0; /* * Use single machine clear, as we cannot handle smp right now @@ -178,6 +177,261 @@ s390_do_machine_check(void) kill_proc(1, SIGPWR, 1); } #endif + + if (mcck.kill_task) { + local_irq_enable(); + printk(KERN_EMERG "mcck: Terminating task because of machine " + "malfunction (code 0x%016llx).\n", mcck.mcck_code); + printk(KERN_EMERG "mcck: task: %s, pid: %d.\n", + current->comm, current->pid); + do_exit(SIGSEGV); + } +} + +/* + * returns 0 if all registers could be validated + * returns 1 otherwise + */ +static int +s390_revalidate_registers(struct mci *mci) +{ + int kill_task; + u64 tmpclock; + u64 zero; + void *fpt_save_area, *fpt_creg_save_area; + + kill_task = 0; + zero = 0; + /* General purpose registers */ + if (!mci->gr) + /* + * General purpose registers couldn't be restored and have + * unknown contents. Process needs to be terminated. + */ + kill_task = 1; + + /* Revalidate floating point registers */ + if (!mci->fp) + /* + * Floating point registers can't be restored and + * therefore the process needs to be terminated. + */ + kill_task = 1; + +#ifndef __s390x__ + asm volatile("ld 0,0(%0)\n" + "ld 2,8(%0)\n" + "ld 4,16(%0)\n" + "ld 6,24(%0)" + : : "a" (&S390_lowcore.floating_pt_save_area)); +#endif + + if (MACHINE_HAS_IEEE) { +#ifdef __s390x__ + fpt_save_area = &S390_lowcore.floating_pt_save_area; + fpt_creg_save_area = &S390_lowcore.fpt_creg_save_area; +#else + fpt_save_area = (void *) S390_lowcore.extended_save_area_addr; + fpt_creg_save_area = fpt_save_area+128; +#endif + /* Floating point control register */ + if (!mci->fc) { + /* + * Floating point control register can't be restored. + * Task will be terminated. + */ + asm volatile ("lfpc 0(%0)" : : "a" (&zero)); + kill_task = 1; + + } + else + asm volatile ( + "lfpc 0(%0)" + : : "a" (fpt_creg_save_area)); + + asm volatile("ld 0,0(%0)\n" + "ld 1,8(%0)\n" + "ld 2,16(%0)\n" + "ld 3,24(%0)\n" + "ld 4,32(%0)\n" + "ld 5,40(%0)\n" + "ld 6,48(%0)\n" + "ld 7,56(%0)\n" + "ld 8,64(%0)\n" + "ld 9,72(%0)\n" + "ld 10,80(%0)\n" + "ld 11,88(%0)\n" + "ld 12,96(%0)\n" + "ld 13,104(%0)\n" + "ld 14,112(%0)\n" + "ld 15,120(%0)\n" + : : "a" (fpt_save_area)); + } + + /* Revalidate access registers */ + asm volatile("lam 0,15,0(%0)" + : : "a" (&S390_lowcore.access_regs_save_area)); + if (!mci->ar) + /* + * Access registers have unknown contents. + * Terminating task. + */ + kill_task = 1; + + /* Revalidate control registers */ + if (!mci->cr) + /* + * Control registers have unknown contents. + * Can't recover and therefore stopping machine. + */ + s390_handle_damage("invalid control registers."); + else +#ifdef __s390x__ + asm volatile("lctlg 0,15,0(%0)" + : : "a" (&S390_lowcore.cregs_save_area)); +#else + asm volatile("lctl 0,15,0(%0)" + : : "a" (&S390_lowcore.cregs_save_area)); +#endif + + /* + * We don't even try to revalidate the TOD register, since we simply + * can't write something sensible into that register. + */ + +#ifdef __s390x__ + /* + * See if we can revalidate the TOD programmable register with its + * old contents (should be zero) otherwise set it to zero. + */ + if (!mci->pr) + asm volatile("sr 0,0\n" + "sckpf" + : : : "0", "cc"); + else + asm volatile( + "l 0,0(%0)\n" + "sckpf" + : : "a" (&S390_lowcore.tod_progreg_save_area) : "0", "cc"); +#endif + + /* Revalidate clock comparator register */ + asm volatile ("stck 0(%1)\n" + "sckc 0(%1)" + : "=m" (tmpclock) : "a" (&(tmpclock)) : "cc", "memory"); + + /* Check if old PSW is valid */ + if (!mci->wp) + /* + * Can't tell if we come from user or kernel mode + * -> stopping machine. + */ + s390_handle_damage("old psw invalid."); + + if (!mci->ms || !mci->pm || !mci->ia) + kill_task = 1; + + return kill_task; +} + +/* + * machine check handler. + */ +void +s390_do_machine_check(struct pt_regs *regs) +{ + struct mci *mci; + struct mcck_struct *mcck; + int umode; + + mci = (struct mci *) &S390_lowcore.mcck_interruption_code; + mcck = &__get_cpu_var(cpu_mcck); + umode = user_mode(regs); + + if (mci->sd) + /* System damage -> stopping machine */ + s390_handle_damage("received system damage machine check."); + + if (mci->pd) { + if (mci->b) { + /* Processing backup -> verify if we can survive this */ + u64 z_mcic, o_mcic, t_mcic; +#ifdef __s390x__ + z_mcic = (1ULL<<63 | 1ULL<<59 | 1ULL<<29); + o_mcic = (1ULL<<43 | 1ULL<<42 | 1ULL<<41 | 1ULL<<40 | + 1ULL<<36 | 1ULL<<35 | 1ULL<<34 | 1ULL<<32 | + 1ULL<<30 | 1ULL<<21 | 1ULL<<20 | 1ULL<<17 | + 1ULL<<16); +#else + z_mcic = (1ULL<<63 | 1ULL<<59 | 1ULL<<57 | 1ULL<<50 | + 1ULL<<29); + o_mcic = (1ULL<<43 | 1ULL<<42 | 1ULL<<41 | 1ULL<<40 | + 1ULL<<36 | 1ULL<<35 | 1ULL<<34 | 1ULL<<32 | + 1ULL<<30 | 1ULL<<20 | 1ULL<<17 | 1ULL<<16); +#endif + t_mcic = *(u64 *)mci; + + if (((t_mcic & z_mcic) != 0) || + ((t_mcic & o_mcic) != o_mcic)) { + s390_handle_damage("processing backup machine " + "check with damage."); + } + if (!umode) + s390_handle_damage("processing backup machine " + "check in kernel mode."); + mcck->kill_task = 1; + mcck->mcck_code = *(unsigned long long *) mci; + } + else { + /* Processing damage -> stopping machine */ + s390_handle_damage("received instruction processing " + "damage machine check."); + } + } + if (s390_revalidate_registers(mci)) { + if (umode) { + /* + * Couldn't restore all register contents while in + * user mode -> mark task for termination. + */ + mcck->kill_task = 1; + mcck->mcck_code = *(unsigned long long *) mci; + set_thread_flag(TIF_MCCK_PENDING); + } + else + /* + * Couldn't restore all register contents while in + * kernel mode -> stopping machine. + */ + s390_handle_damage("unable to revalidate registers."); + } + + if (mci->se) + /* Storage error uncorrected */ + s390_handle_damage("received storage error uncorrected " + "machine check."); + + if (mci->ke) + /* Storage key-error uncorrected */ + s390_handle_damage("received storage key-error uncorrected " + "machine check."); + + if (mci->ds && mci->fa) + /* Storage degradation */ + s390_handle_damage("received storage degradation machine " + "check."); + + if (mci->cp) { + /* Channel report word pending */ + mcck->channel_report = 1; + set_thread_flag(TIF_MCCK_PENDING); + } + + if (mci->w) { + /* Warning pending */ + mcck->warning = 1; + set_thread_flag(TIF_MCCK_PENDING); + } } /* @@ -189,9 +443,8 @@ static int machine_check_init(void) { init_MUTEX_LOCKED(&m_sem); - ctl_clear_bit(14, 25); /* disable damage MCH */ - ctl_set_bit(14, 26); /* enable degradation MCH */ - ctl_set_bit(14, 27); /* enable system recovery MCH */ + ctl_clear_bit(14, 25); /* disable external damage MCH */ + ctl_set_bit(14, 27); /* enable system recovery MCH */ #ifdef CONFIG_MACHCHK_WARNING ctl_set_bit(14, 24); /* enable warning MCH */ #endif diff --git a/drivers/s390/s390mach.h b/drivers/s390/s390mach.h index 7e26f0f..4eaa701 100644 --- a/drivers/s390/s390mach.h +++ b/drivers/s390/s390mach.h @@ -16,20 +16,45 @@ struct mci { __u32 sd : 1; /* 00 system damage */ __u32 pd : 1; /* 01 instruction-processing damage */ __u32 sr : 1; /* 02 system recovery */ - __u32 to_be_defined_1 : 4; /* 03-06 */ + __u32 to_be_defined_1 : 1; /* 03 */ + __u32 cd : 1; /* 04 timing-facility damage */ + __u32 ed : 1; /* 05 external damage */ + __u32 to_be_defined_2 : 1; /* 06 */ __u32 dg : 1; /* 07 degradation */ __u32 w : 1; /* 08 warning pending */ __u32 cp : 1; /* 09 channel-report pending */ - __u32 to_be_defined_2 : 6; /* 10-15 */ + __u32 sp : 1; /* 10 service-processor damage */ + __u32 ck : 1; /* 11 channel-subsystem damage */ + __u32 to_be_defined_3 : 2; /* 12-13 */ + __u32 b : 1; /* 14 backed up */ + __u32 to_be_defined_4 : 1; /* 15 */ __u32 se : 1; /* 16 storage error uncorrected */ __u32 sc : 1; /* 17 storage error corrected */ __u32 ke : 1; /* 18 storage-key error uncorrected */ __u32 ds : 1; /* 19 storage degradation */ - __u32 to_be_defined_3 : 4; /* 20-23 */ + __u32 wp : 1; /* 20 psw mwp validity */ + __u32 ms : 1; /* 21 psw mask and key validity */ + __u32 pm : 1; /* 22 psw program mask and cc validity */ + __u32 ia : 1; /* 23 psw instruction address validity */ __u32 fa : 1; /* 24 failing storage address validity */ - __u32 to_be_defined_4 : 7; /* 25-31 */ + __u32 to_be_defined_5 : 1; /* 25 */ + __u32 ec : 1; /* 26 external damage code validity */ + __u32 fp : 1; /* 27 floating point register validity */ + __u32 gr : 1; /* 28 general register validity */ + __u32 cr : 1; /* 29 control register validity */ + __u32 to_be_defined_6 : 1; /* 30 */ + __u32 st : 1; /* 31 storage logical validity */ __u32 ie : 1; /* 32 indirect storage error */ - __u32 to_be_defined_5 : 31; /* 33-63 */ + __u32 ar : 1; /* 33 access register validity */ + __u32 da : 1; /* 34 delayed access exception */ + __u32 to_be_defined_7 : 7; /* 35-41 */ + __u32 pr : 1; /* 42 tod programmable register validity */ + __u32 fc : 1; /* 43 fp control register validity */ + __u32 ap : 1; /* 44 ancillary report */ + __u32 to_be_defined_8 : 1; /* 45 */ + __u32 ct : 1; /* 46 cpu timer validity */ + __u32 cc : 1; /* 47 clock comparator validity */ + __u32 to_be_defined_9 : 16; /* 47-63 */ }; /* |