X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fs390%2Fs390mach.c;h=5399c5d99b81e0b5bc8f56949d4ec937711b6e67;hb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;hp=2138af884f8205f3928212e0792b6b5fb6a3d327;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git diff --git a/drivers/s390/s390mach.c b/drivers/s390/s390mach.c index 2138af884..5399c5d99 100644 --- a/drivers/s390/s390mach.c +++ b/drivers/s390/s390mach.c @@ -8,10 +8,12 @@ * Martin Schwidefsky (schwidefsky@de.ibm.com) */ -#include #include #include #include +#include +#include +#include #include @@ -21,37 +23,23 @@ // #define DBG(args,...) do {} while (0); static struct semaphore m_sem; -static struct semaphore s_sem; -extern int css_process_crw(int); +extern int css_process_crw(int, int); extern int chsc_process_crw(void); extern int chp_process_crw(int, int); extern void css_reiterate_subchannels(void); -extern void css_trigger_slow_path(void); -static void +extern struct workqueue_struct *slow_path_wq; +extern struct work_struct slow_path_work; + +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)); -} - -static int -s390_mchk_slow_path(void *param) -{ - struct semaphore *sem; - - sem = (struct semaphore *)param; - /* Set a nice name. */ - daemonize("kslowcrw"); -repeat: - down_interruptible(sem); - css_trigger_slow_path(); - goto repeat; - return 0; + for(;;); } /* @@ -62,35 +50,59 @@ repeat: static int s390_collect_crw_info(void *param) { - struct crw crw; + struct crw crw[2]; int ccode, ret, slow; struct semaphore *sem; + unsigned int chain; sem = (struct semaphore *)param; - /* Set a nice name. */ - daemonize("kmcheck"); repeat: down_interruptible(sem); slow = 0; + chain = 0; while (1) { - ccode = stcrw(&crw); + if (unlikely(chain > 1)) { + struct crw tmp_crw; + + printk(KERN_WARNING"%s: Code does not support more " + "than two chained crws; please report to " + "linux390@de.ibm.com!\n", __FUNCTION__); + ccode = stcrw(&tmp_crw); + printk(KERN_WARNING"%s: crw reports slct=%d, oflw=%d, " + "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n", + __FUNCTION__, tmp_crw.slct, tmp_crw.oflw, + tmp_crw.chn, tmp_crw.rsc, tmp_crw.anc, + tmp_crw.erc, tmp_crw.rsid); + printk(KERN_WARNING"%s: This was crw number %x in the " + "chain\n", __FUNCTION__, chain); + if (ccode != 0) + break; + chain = tmp_crw.chn ? chain + 1 : 0; + continue; + } + ccode = stcrw(&crw[chain]); if (ccode != 0) break; DBG(KERN_DEBUG "crw_info : CRW reports slct=%d, oflw=%d, " "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n", - crw.slct, crw.oflw, crw.chn, crw.rsc, crw.anc, - crw.erc, crw.rsid); + crw[chain].slct, crw[chain].oflw, crw[chain].chn, + crw[chain].rsc, crw[chain].anc, crw[chain].erc, + crw[chain].rsid); /* Check for overflows. */ - if (crw.oflw) { + if (crw[chain].oflw) { pr_debug("%s: crw overflow detected!\n", __FUNCTION__); css_reiterate_subchannels(); + chain = 0; slow = 1; continue; } - switch (crw.rsc) { + switch (crw[chain].rsc) { case CRW_RSC_SCH: - pr_debug("source is subchannel %04X\n", crw.rsid); - ret = css_process_crw (crw.rsid); + if (crw[0].chn && !chain) + break; + pr_debug("source is subchannel %04X\n", crw[0].rsid); + ret = css_process_crw (crw[0].rsid, + chain ? crw[1].rsid : 0); if (ret == -EAGAIN) slow = 1; break; @@ -98,18 +110,28 @@ repeat: pr_debug("source is monitoring facility\n"); break; case CRW_RSC_CPATH: - pr_debug("source is channel path %02X\n", crw.rsid); - switch (crw.erc) { + pr_debug("source is channel path %02X\n", crw[0].rsid); + /* + * Check for solicited machine checks. These are + * created by reset channel path and need not be + * reported to the common I/O layer. + */ + if (crw[chain].slct) { + DBG(KERN_INFO"solicited machine check for " + "channel path %02X\n", crw[0].rsid); + break; + } + switch (crw[0].erc) { case CRW_ERC_IPARM: /* Path has come. */ - ret = chp_process_crw(crw.rsid, 1); + ret = chp_process_crw(crw[0].rsid, 1); break; case CRW_ERC_PERRI: /* Path has gone. */ case CRW_ERC_PERRN: - ret = chp_process_crw(crw.rsid, 0); + ret = chp_process_crw(crw[0].rsid, 0); break; default: pr_debug("Don't know how to handle erc=%x\n", - crw.erc); + crw[0].erc); ret = 0; } if (ret == -EAGAIN) @@ -128,47 +150,48 @@ repeat: pr_debug("unknown source\n"); break; } + /* chain is always 0 or 1 here. */ + chain = crw[chain].chn ? chain + 1 : 0; } if (slow) - up(&s_sem); + queue_work(slow_path_wq, &slow_path_work); goto 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"); - - 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"); + /* + * 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->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 @@ -181,7 +204,7 @@ 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 @@ -191,6 +214,287 @@ 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 CONFIG_64BIT + 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 CONFIG_64BIT + 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), "m" (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 CONFIG_64BIT + 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 CONFIG_64BIT + /* + * 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; +} + +#define MAX_IPD_COUNT 29 +#define MAX_IPD_TIME (5 * 60 * USEC_PER_SEC) /* 5 minutes */ + +/* + * machine check handler. + */ +void +s390_do_machine_check(struct pt_regs *regs) +{ + static DEFINE_SPINLOCK(ipd_lock); + static unsigned long long last_ipd; + static int ipd_count; + unsigned long long tmp; + struct mci *mci; + struct mcck_struct *mcck; + int umode; + + lockdep_off(); + + 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 CONFIG_64BIT + 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."); + } + + /* + * Nullifying exigent condition, therefore we might + * retry this instruction. + */ + + spin_lock(&ipd_lock); + + tmp = get_clock(); + + if (((tmp - last_ipd) >> 12) < MAX_IPD_TIME) + ipd_count++; + else + ipd_count = 1; + + last_ipd = tmp; + + if (ipd_count == MAX_IPD_COUNT) + s390_handle_damage("too many ipd retries."); + + spin_unlock(&ipd_lock); + } + 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); + } + lockdep_on(); } /* @@ -202,10 +506,8 @@ static int machine_check_init(void) { init_MUTEX_LOCKED(&m_sem); - init_MUTEX_LOCKED( &s_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 @@ -225,8 +527,7 @@ arch_initcall(machine_check_init); static int __init machine_check_crw_init (void) { - kernel_thread(s390_collect_crw_info, &m_sem, CLONE_FS|CLONE_FILES); - kernel_thread(s390_mchk_slow_path, &s_sem, CLONE_FS|CLONE_FILES); + kthread_run(s390_collect_crw_info, &m_sem, "kmcheck"); ctl_set_bit(14, 28); /* enable channel report MCH */ return 0; }