11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * S390 version 3a53c8fabSHeiko Carstens * Copyright IBM Corp. 1999 41da177e4SLinus Torvalds * Author(s): Hartmut Penner (hp@de.ibm.com) 51da177e4SLinus Torvalds * Ulrich Weigand (uweigand@de.ibm.com) 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * Derived from "arch/i386/mm/fault.c" 81da177e4SLinus Torvalds * Copyright (C) 1995 Linus Torvalds 91da177e4SLinus Torvalds */ 101da177e4SLinus Torvalds 11052ff461SHeiko Carstens #include <linux/kernel_stat.h> 12cdd6c482SIngo Molnar #include <linux/perf_event.h> 131da177e4SLinus Torvalds #include <linux/signal.h> 141da177e4SLinus Torvalds #include <linux/sched.h> 151da177e4SLinus Torvalds #include <linux/kernel.h> 161da177e4SLinus Torvalds #include <linux/errno.h> 171da177e4SLinus Torvalds #include <linux/string.h> 181da177e4SLinus Torvalds #include <linux/types.h> 191da177e4SLinus Torvalds #include <linux/ptrace.h> 201da177e4SLinus Torvalds #include <linux/mman.h> 211da177e4SLinus Torvalds #include <linux/mm.h> 227757591aSHeiko Carstens #include <linux/compat.h> 231da177e4SLinus Torvalds #include <linux/smp.h> 241eeb66a1SChristoph Hellwig #include <linux/kdebug.h> 251da177e4SLinus Torvalds #include <linux/init.h> 261da177e4SLinus Torvalds #include <linux/console.h> 271da177e4SLinus Torvalds #include <linux/module.h> 281da177e4SLinus Torvalds #include <linux/hardirq.h> 294ba069b8SMichael Grundy #include <linux/kprobes.h> 30be5ec363SMartin Schwidefsky #include <linux/uaccess.h> 3153492b1dSGerald Schaefer #include <linux/hugetlb.h> 32cbb870c8SHeiko Carstens #include <asm/asm-offsets.h> 331ec2772eSMartin Schwidefsky #include <asm/diag.h> 341da177e4SLinus Torvalds #include <asm/pgtable.h> 35d7b250e2SHeiko Carstens #include <asm/irq.h> 366252d702SMartin Schwidefsky #include <asm/mmu_context.h> 37a0616cdeSDavid Howells #include <asm/facility.h> 38a806170eSHeiko Carstens #include "../kernel/entry.h" 391da177e4SLinus Torvalds 401da177e4SLinus Torvalds #define __FAIL_ADDR_MASK -4096L 411da177e4SLinus Torvalds #define __SUBCODE_MASK 0x0600 421da177e4SLinus Torvalds #define __PF_RES_FIELD 0x8000000000000000ULL 431da177e4SLinus Torvalds 4450d7280dSMartin Schwidefsky #define VM_FAULT_BADCONTEXT 0x010000 4550d7280dSMartin Schwidefsky #define VM_FAULT_BADMAP 0x020000 4650d7280dSMartin Schwidefsky #define VM_FAULT_BADACCESS 0x040000 47f2c76e3bSHeiko Carstens #define VM_FAULT_SIGNAL 0x080000 4824eb3a82SDominik Dingel #define VM_FAULT_PFAULT 0x100000 4950d7280dSMartin Schwidefsky 50a4f32bdbSHeiko Carstens static unsigned long store_indication __read_mostly; 5192f842eaSMartin Schwidefsky 52a4f32bdbSHeiko Carstens static int __init fault_init(void) 5392f842eaSMartin Schwidefsky { 54a4f32bdbSHeiko Carstens if (test_facility(75)) 5592f842eaSMartin Schwidefsky store_indication = 0xc00; 56a4f32bdbSHeiko Carstens return 0; 5792f842eaSMartin Schwidefsky } 58a4f32bdbSHeiko Carstens early_initcall(fault_init); 5992f842eaSMartin Schwidefsky 607ecb344aSMartin Schwidefsky static inline int notify_page_fault(struct pt_regs *regs) 6110c1031fSMartin Schwidefsky { 6233464e3bSChristoph Hellwig int ret = 0; 6333464e3bSChristoph Hellwig 6433464e3bSChristoph Hellwig /* kprobe_running() needs smp_processor_id() */ 6522e0a046SHeiko Carstens if (kprobes_built_in() && !user_mode(regs)) { 6633464e3bSChristoph Hellwig preempt_disable(); 6733464e3bSChristoph Hellwig if (kprobe_running() && kprobe_fault_handler(regs, 14)) 6833464e3bSChristoph Hellwig ret = 1; 6933464e3bSChristoph Hellwig preempt_enable(); 7033464e3bSChristoph Hellwig } 7133464e3bSChristoph Hellwig return ret; 724ba069b8SMichael Grundy } 734ba069b8SMichael Grundy 741da177e4SLinus Torvalds 751da177e4SLinus Torvalds /* 761da177e4SLinus Torvalds * Unlock any spinlocks which will prevent us from getting the 77cefc8be8SKirill Korotaev * message out. 781da177e4SLinus Torvalds */ 791da177e4SLinus Torvalds void bust_spinlocks(int yes) 801da177e4SLinus Torvalds { 811da177e4SLinus Torvalds if (yes) { 821da177e4SLinus Torvalds oops_in_progress = 1; 831da177e4SLinus Torvalds } else { 841da177e4SLinus Torvalds int loglevel_save = console_loglevel; 851da177e4SLinus Torvalds console_unblank(); 861da177e4SLinus Torvalds oops_in_progress = 0; 871da177e4SLinus Torvalds /* 881da177e4SLinus Torvalds * OK, the message is on the console. Now we call printk() 891da177e4SLinus Torvalds * without oops_in_progress set so that printk will give klogd 901da177e4SLinus Torvalds * a poke. Hold onto your hats... 911da177e4SLinus Torvalds */ 921da177e4SLinus Torvalds console_loglevel = 15; 931da177e4SLinus Torvalds printk(" "); 941da177e4SLinus Torvalds console_loglevel = loglevel_save; 951da177e4SLinus Torvalds } 961da177e4SLinus Torvalds } 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds /* 99482b05ddSGerald Schaefer * Returns the address space associated with the fault. 10061365e13SMartin Schwidefsky * Returns 0 for kernel space and 1 for user space. 1011da177e4SLinus Torvalds */ 102457f2180SHeiko Carstens static inline int user_space_fault(struct pt_regs *regs) 1031da177e4SLinus Torvalds { 104457f2180SHeiko Carstens unsigned long trans_exc_code; 105457f2180SHeiko Carstens 1061da177e4SLinus Torvalds /* 10761365e13SMartin Schwidefsky * The lowest two bits of the translation exception 10861365e13SMartin Schwidefsky * identification indicate which paging table was used. 1091da177e4SLinus Torvalds */ 110457f2180SHeiko Carstens trans_exc_code = regs->int_parm_long & 3; 111457f2180SHeiko Carstens if (trans_exc_code == 3) /* home space -> kernel */ 112457f2180SHeiko Carstens return 0; 113457f2180SHeiko Carstens if (user_mode(regs)) 114457f2180SHeiko Carstens return 1; 115457f2180SHeiko Carstens if (trans_exc_code == 2) /* secondary space -> set_fs */ 11661365e13SMartin Schwidefsky return current->thread.mm_segment.ar4; 117457f2180SHeiko Carstens if (current->flags & PF_VCPU) 118457f2180SHeiko Carstens return 1; 119457f2180SHeiko Carstens return 0; 1201da177e4SLinus Torvalds } 1211da177e4SLinus Torvalds 1223b7df342SHeiko Carstens static int bad_address(void *p) 1233b7df342SHeiko Carstens { 1243b7df342SHeiko Carstens unsigned long dummy; 1253b7df342SHeiko Carstens 1263b7df342SHeiko Carstens return probe_kernel_address((unsigned long *)p, dummy); 1273b7df342SHeiko Carstens } 1283b7df342SHeiko Carstens 1293b7df342SHeiko Carstens static void dump_pagetable(unsigned long asce, unsigned long address) 1303b7df342SHeiko Carstens { 1313b7df342SHeiko Carstens unsigned long *table = __va(asce & PAGE_MASK); 1323b7df342SHeiko Carstens 1333b7df342SHeiko Carstens pr_alert("AS:%016lx ", asce); 1343b7df342SHeiko Carstens switch (asce & _ASCE_TYPE_MASK) { 1353b7df342SHeiko Carstens case _ASCE_TYPE_REGION1: 1363b7df342SHeiko Carstens table = table + ((address >> 53) & 0x7ff); 1373b7df342SHeiko Carstens if (bad_address(table)) 1383b7df342SHeiko Carstens goto bad; 1393b7df342SHeiko Carstens pr_cont("R1:%016lx ", *table); 1403b7df342SHeiko Carstens if (*table & _REGION_ENTRY_INVALID) 1413b7df342SHeiko Carstens goto out; 1423b7df342SHeiko Carstens table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); 1433b7df342SHeiko Carstens /* fallthrough */ 1443b7df342SHeiko Carstens case _ASCE_TYPE_REGION2: 1453b7df342SHeiko Carstens table = table + ((address >> 42) & 0x7ff); 1463b7df342SHeiko Carstens if (bad_address(table)) 1473b7df342SHeiko Carstens goto bad; 1483b7df342SHeiko Carstens pr_cont("R2:%016lx ", *table); 1493b7df342SHeiko Carstens if (*table & _REGION_ENTRY_INVALID) 1503b7df342SHeiko Carstens goto out; 1513b7df342SHeiko Carstens table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); 1523b7df342SHeiko Carstens /* fallthrough */ 1533b7df342SHeiko Carstens case _ASCE_TYPE_REGION3: 1543b7df342SHeiko Carstens table = table + ((address >> 31) & 0x7ff); 1553b7df342SHeiko Carstens if (bad_address(table)) 1563b7df342SHeiko Carstens goto bad; 1573b7df342SHeiko Carstens pr_cont("R3:%016lx ", *table); 1583b7df342SHeiko Carstens if (*table & (_REGION_ENTRY_INVALID | _REGION3_ENTRY_LARGE)) 1593b7df342SHeiko Carstens goto out; 1603b7df342SHeiko Carstens table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); 1613b7df342SHeiko Carstens /* fallthrough */ 1623b7df342SHeiko Carstens case _ASCE_TYPE_SEGMENT: 1633b7df342SHeiko Carstens table = table + ((address >> 20) & 0x7ff); 1643b7df342SHeiko Carstens if (bad_address(table)) 1653b7df342SHeiko Carstens goto bad; 16691c0837eSJoe Perches pr_cont("S:%016lx ", *table); 1673b7df342SHeiko Carstens if (*table & (_SEGMENT_ENTRY_INVALID | _SEGMENT_ENTRY_LARGE)) 1683b7df342SHeiko Carstens goto out; 1693b7df342SHeiko Carstens table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN); 1703b7df342SHeiko Carstens } 1713b7df342SHeiko Carstens table = table + ((address >> 12) & 0xff); 1723b7df342SHeiko Carstens if (bad_address(table)) 1733b7df342SHeiko Carstens goto bad; 1743b7df342SHeiko Carstens pr_cont("P:%016lx ", *table); 1753b7df342SHeiko Carstens out: 1763b7df342SHeiko Carstens pr_cont("\n"); 1773b7df342SHeiko Carstens return; 1783b7df342SHeiko Carstens bad: 1793b7df342SHeiko Carstens pr_cont("BAD\n"); 1803b7df342SHeiko Carstens } 1813b7df342SHeiko Carstens 1823b7df342SHeiko Carstens static void dump_fault_info(struct pt_regs *regs) 1833b7df342SHeiko Carstens { 1843b7df342SHeiko Carstens unsigned long asce; 1853b7df342SHeiko Carstens 1863b7df342SHeiko Carstens pr_alert("Fault in "); 1873b7df342SHeiko Carstens switch (regs->int_parm_long & 3) { 1883b7df342SHeiko Carstens case 3: 1893b7df342SHeiko Carstens pr_cont("home space "); 1903b7df342SHeiko Carstens break; 1913b7df342SHeiko Carstens case 2: 1923b7df342SHeiko Carstens pr_cont("secondary space "); 1933b7df342SHeiko Carstens break; 1943b7df342SHeiko Carstens case 1: 1953b7df342SHeiko Carstens pr_cont("access register "); 1963b7df342SHeiko Carstens break; 1973b7df342SHeiko Carstens case 0: 1983b7df342SHeiko Carstens pr_cont("primary space "); 1993b7df342SHeiko Carstens break; 2003b7df342SHeiko Carstens } 2013b7df342SHeiko Carstens pr_cont("mode while using "); 2023b7df342SHeiko Carstens if (!user_space_fault(regs)) { 2033b7df342SHeiko Carstens asce = S390_lowcore.kernel_asce; 2043b7df342SHeiko Carstens pr_cont("kernel "); 2053b7df342SHeiko Carstens } 2063b7df342SHeiko Carstens #ifdef CONFIG_PGSTE 2073b7df342SHeiko Carstens else if ((current->flags & PF_VCPU) && S390_lowcore.gmap) { 2083b7df342SHeiko Carstens struct gmap *gmap = (struct gmap *)S390_lowcore.gmap; 2093b7df342SHeiko Carstens asce = gmap->asce; 2103b7df342SHeiko Carstens pr_cont("gmap "); 2113b7df342SHeiko Carstens } 2123b7df342SHeiko Carstens #endif 2133b7df342SHeiko Carstens else { 2143b7df342SHeiko Carstens asce = S390_lowcore.user_asce; 2153b7df342SHeiko Carstens pr_cont("user "); 2163b7df342SHeiko Carstens } 2173b7df342SHeiko Carstens pr_cont("ASCE.\n"); 2183b7df342SHeiko Carstens dump_pagetable(asce, regs->int_parm_long & __FAIL_ADDR_MASK); 2193b7df342SHeiko Carstens } 2203b7df342SHeiko Carstens 221aa33c8cbSMartin Schwidefsky static inline void report_user_fault(struct pt_regs *regs, long signr) 222ab3c68eeSHeiko Carstens { 223ab3c68eeSHeiko Carstens if ((task_pid_nr(current) > 1) && !show_unhandled_signals) 224ab3c68eeSHeiko Carstens return; 225ab3c68eeSHeiko Carstens if (!unhandled_signal(current, signr)) 226ab3c68eeSHeiko Carstens return; 227ab3c68eeSHeiko Carstens if (!printk_ratelimit()) 228ab3c68eeSHeiko Carstens return; 229413d4047SHeiko Carstens printk(KERN_ALERT "User process fault: interruption code %04x ilc:%d ", 230413d4047SHeiko Carstens regs->int_code & 0xffff, regs->int_code >> 17); 231ab3c68eeSHeiko Carstens print_vma_addr(KERN_CONT "in ", regs->psw.addr & PSW_ADDR_INSN); 232aa33c8cbSMartin Schwidefsky printk(KERN_CONT "\n"); 2333b7df342SHeiko Carstens printk(KERN_ALERT "failing address: %016lx TEID: %016lx\n", 2343b7df342SHeiko Carstens regs->int_parm_long & __FAIL_ADDR_MASK, regs->int_parm_long); 2353b7df342SHeiko Carstens dump_fault_info(regs); 236ab3c68eeSHeiko Carstens show_regs(regs); 237ab3c68eeSHeiko Carstens } 238ab3c68eeSHeiko Carstens 2391da177e4SLinus Torvalds /* 2401da177e4SLinus Torvalds * Send SIGSEGV to task. This is an external routine 2411da177e4SLinus Torvalds * to keep the stack usage of do_page_fault small. 2421da177e4SLinus Torvalds */ 243aa33c8cbSMartin Schwidefsky static noinline void do_sigsegv(struct pt_regs *regs, int si_code) 2441da177e4SLinus Torvalds { 2451da177e4SLinus Torvalds struct siginfo si; 2461da177e4SLinus Torvalds 247aa33c8cbSMartin Schwidefsky report_user_fault(regs, SIGSEGV); 2481da177e4SLinus Torvalds si.si_signo = SIGSEGV; 2491da177e4SLinus Torvalds si.si_code = si_code; 250aa33c8cbSMartin Schwidefsky si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK); 2511da177e4SLinus Torvalds force_sig_info(SIGSEGV, &si, current); 2521da177e4SLinus Torvalds } 2531da177e4SLinus Torvalds 254aa33c8cbSMartin Schwidefsky static noinline void do_no_context(struct pt_regs *regs) 25510c1031fSMartin Schwidefsky { 25610c1031fSMartin Schwidefsky const struct exception_table_entry *fixup; 25710c1031fSMartin Schwidefsky 25810c1031fSMartin Schwidefsky /* Are we prepared to handle this kernel fault? */ 25950d7280dSMartin Schwidefsky fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN); 26010c1031fSMartin Schwidefsky if (fixup) { 261fecc868aSHeiko Carstens regs->psw.addr = extable_fixup(fixup); 26210c1031fSMartin Schwidefsky return; 26310c1031fSMartin Schwidefsky } 26410c1031fSMartin Schwidefsky 26510c1031fSMartin Schwidefsky /* 26610c1031fSMartin Schwidefsky * Oops. The kernel tried to access some bad page. We'll have to 26710c1031fSMartin Schwidefsky * terminate things with extreme prejudice. 26810c1031fSMartin Schwidefsky */ 269457f2180SHeiko Carstens if (!user_space_fault(regs)) 27010c1031fSMartin Schwidefsky printk(KERN_ALERT "Unable to handle kernel pointer dereference" 2713b7df342SHeiko Carstens " in virtual kernel address space\n"); 27210c1031fSMartin Schwidefsky else 27310c1031fSMartin Schwidefsky printk(KERN_ALERT "Unable to handle kernel paging request" 2743b7df342SHeiko Carstens " in virtual user address space\n"); 2753b7df342SHeiko Carstens printk(KERN_ALERT "failing address: %016lx TEID: %016lx\n", 2763b7df342SHeiko Carstens regs->int_parm_long & __FAIL_ADDR_MASK, regs->int_parm_long); 2773b7df342SHeiko Carstens dump_fault_info(regs); 278aa33c8cbSMartin Schwidefsky die(regs, "Oops"); 27910c1031fSMartin Schwidefsky do_exit(SIGKILL); 28010c1031fSMartin Schwidefsky } 28110c1031fSMartin Schwidefsky 282aa33c8cbSMartin Schwidefsky static noinline void do_low_address(struct pt_regs *regs) 28310c1031fSMartin Schwidefsky { 28410c1031fSMartin Schwidefsky /* Low-address protection hit in kernel mode means 28510c1031fSMartin Schwidefsky NULL pointer write access in kernel mode. */ 28610c1031fSMartin Schwidefsky if (regs->psw.mask & PSW_MASK_PSTATE) { 28710c1031fSMartin Schwidefsky /* Low-address protection hit in user mode 'cannot happen'. */ 288aa33c8cbSMartin Schwidefsky die (regs, "Low-address protection"); 28910c1031fSMartin Schwidefsky do_exit(SIGKILL); 29010c1031fSMartin Schwidefsky } 29110c1031fSMartin Schwidefsky 292aa33c8cbSMartin Schwidefsky do_no_context(regs); 29310c1031fSMartin Schwidefsky } 29410c1031fSMartin Schwidefsky 295aa33c8cbSMartin Schwidefsky static noinline void do_sigbus(struct pt_regs *regs) 29610c1031fSMartin Schwidefsky { 29710c1031fSMartin Schwidefsky struct task_struct *tsk = current; 29836bf9680SMartin Schwidefsky struct siginfo si; 29910c1031fSMartin Schwidefsky 30010c1031fSMartin Schwidefsky /* 30110c1031fSMartin Schwidefsky * Send a sigbus, regardless of whether we were in kernel 30210c1031fSMartin Schwidefsky * or user mode. 30310c1031fSMartin Schwidefsky */ 30436bf9680SMartin Schwidefsky si.si_signo = SIGBUS; 30536bf9680SMartin Schwidefsky si.si_errno = 0; 30636bf9680SMartin Schwidefsky si.si_code = BUS_ADRERR; 307aa33c8cbSMartin Schwidefsky si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK); 30836bf9680SMartin Schwidefsky force_sig_info(SIGBUS, &si, tsk); 30910c1031fSMartin Schwidefsky } 31010c1031fSMartin Schwidefsky 311aa33c8cbSMartin Schwidefsky static noinline void do_fault_error(struct pt_regs *regs, int fault) 31250d7280dSMartin Schwidefsky { 31350d7280dSMartin Schwidefsky int si_code; 31450d7280dSMartin Schwidefsky 31550d7280dSMartin Schwidefsky switch (fault) { 31650d7280dSMartin Schwidefsky case VM_FAULT_BADACCESS: 31750d7280dSMartin Schwidefsky case VM_FAULT_BADMAP: 31850d7280dSMartin Schwidefsky /* Bad memory access. Check if it is kernel or user space. */ 3197d256175SHeiko Carstens if (user_mode(regs)) { 32050d7280dSMartin Schwidefsky /* User mode accesses just cause a SIGSEGV */ 32150d7280dSMartin Schwidefsky si_code = (fault == VM_FAULT_BADMAP) ? 32250d7280dSMartin Schwidefsky SEGV_MAPERR : SEGV_ACCERR; 323aa33c8cbSMartin Schwidefsky do_sigsegv(regs, si_code); 32450d7280dSMartin Schwidefsky return; 32550d7280dSMartin Schwidefsky } 32650d7280dSMartin Schwidefsky case VM_FAULT_BADCONTEXT: 32724eb3a82SDominik Dingel case VM_FAULT_PFAULT: 328aa33c8cbSMartin Schwidefsky do_no_context(regs); 32950d7280dSMartin Schwidefsky break; 330f2c76e3bSHeiko Carstens case VM_FAULT_SIGNAL: 331f2c76e3bSHeiko Carstens if (!user_mode(regs)) 332f2c76e3bSHeiko Carstens do_no_context(regs); 333f2c76e3bSHeiko Carstens break; 33450d7280dSMartin Schwidefsky default: /* fault & VM_FAULT_ERROR */ 33599583181SHeiko Carstens if (fault & VM_FAULT_OOM) { 3367d256175SHeiko Carstens if (!user_mode(regs)) 337aa33c8cbSMartin Schwidefsky do_no_context(regs); 33899583181SHeiko Carstens else 33950d7280dSMartin Schwidefsky pagefault_out_of_memory(); 34033692f27SLinus Torvalds } else if (fault & VM_FAULT_SIGSEGV) { 34133692f27SLinus Torvalds /* Kernel mode? Handle exceptions or die */ 34233692f27SLinus Torvalds if (!user_mode(regs)) 34333692f27SLinus Torvalds do_no_context(regs); 34433692f27SLinus Torvalds else 34533692f27SLinus Torvalds do_sigsegv(regs, SEGV_MAPERR); 34699583181SHeiko Carstens } else if (fault & VM_FAULT_SIGBUS) { 34750d7280dSMartin Schwidefsky /* Kernel mode? Handle exceptions or die */ 3487d256175SHeiko Carstens if (!user_mode(regs)) 349aa33c8cbSMartin Schwidefsky do_no_context(regs); 35036bf9680SMartin Schwidefsky else 351aa33c8cbSMartin Schwidefsky do_sigbus(regs); 35250d7280dSMartin Schwidefsky } else 35350d7280dSMartin Schwidefsky BUG(); 35450d7280dSMartin Schwidefsky break; 35550d7280dSMartin Schwidefsky } 35650d7280dSMartin Schwidefsky } 35750d7280dSMartin Schwidefsky 3581da177e4SLinus Torvalds /* 3591da177e4SLinus Torvalds * This routine handles page faults. It determines the address, 3601da177e4SLinus Torvalds * and the problem, and then passes it off to one of the appropriate 3611da177e4SLinus Torvalds * routines. 3621da177e4SLinus Torvalds * 36350d7280dSMartin Schwidefsky * interruption code (int_code): 3641da177e4SLinus Torvalds * 04 Protection -> Write-Protection (suprression) 3651da177e4SLinus Torvalds * 10 Segment translation -> Not present (nullification) 3661da177e4SLinus Torvalds * 11 Page translation -> Not present (nullification) 3671da177e4SLinus Torvalds * 3b Region third trans. -> Not present (nullification) 3681da177e4SLinus Torvalds */ 369aa33c8cbSMartin Schwidefsky static inline int do_exception(struct pt_regs *regs, int access) 3701da177e4SLinus Torvalds { 37124eb3a82SDominik Dingel #ifdef CONFIG_PGSTE 37224eb3a82SDominik Dingel struct gmap *gmap; 37324eb3a82SDominik Dingel #endif 3741da177e4SLinus Torvalds struct task_struct *tsk; 3751da177e4SLinus Torvalds struct mm_struct *mm; 3761da177e4SLinus Torvalds struct vm_area_struct *vma; 377aa33c8cbSMartin Schwidefsky unsigned long trans_exc_code; 3781da177e4SLinus Torvalds unsigned long address; 37933ce6140SHeiko Carstens unsigned int flags; 38033ce6140SHeiko Carstens int fault; 38110c1031fSMartin Schwidefsky 38239efd4ecSMartin Schwidefsky tsk = current; 38339efd4ecSMartin Schwidefsky /* 38439efd4ecSMartin Schwidefsky * The instruction that caused the program check has 38539efd4ecSMartin Schwidefsky * been nullified. Don't signal single step via SIGTRAP. 38639efd4ecSMartin Schwidefsky */ 387d3a73acbSMartin Schwidefsky clear_pt_regs_flag(regs, PIF_PER_TRAP); 38839efd4ecSMartin Schwidefsky 3897ecb344aSMartin Schwidefsky if (notify_page_fault(regs)) 39050d7280dSMartin Schwidefsky return 0; 3911da177e4SLinus Torvalds 3921da177e4SLinus Torvalds mm = tsk->mm; 393aa33c8cbSMartin Schwidefsky trans_exc_code = regs->int_parm_long; 3941da177e4SLinus Torvalds 3951da177e4SLinus Torvalds /* 3961da177e4SLinus Torvalds * Verify that the fault happened in user space, that 3971da177e4SLinus Torvalds * we are not in an interrupt and that there is a 3981da177e4SLinus Torvalds * user context. 3991da177e4SLinus Torvalds */ 40050d7280dSMartin Schwidefsky fault = VM_FAULT_BADCONTEXT; 40170ffdb93SDavid Hildenbrand if (unlikely(!user_space_fault(regs) || faulthandler_disabled() || !mm)) 40250d7280dSMartin Schwidefsky goto out; 4031da177e4SLinus Torvalds 40461365e13SMartin Schwidefsky address = trans_exc_code & __FAIL_ADDR_MASK; 405a8b0ca17SPeter Zijlstra perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); 406f2c76e3bSHeiko Carstens flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; 407759496baSJohannes Weiner if (user_mode(regs)) 408759496baSJohannes Weiner flags |= FAULT_FLAG_USER; 40933ce6140SHeiko Carstens if (access == VM_WRITE || (trans_exc_code & store_indication) == 0x400) 41033ce6140SHeiko Carstens flags |= FAULT_FLAG_WRITE; 4111da177e4SLinus Torvalds down_read(&mm->mmap_sem); 4121da177e4SLinus Torvalds 413e5992f2eSMartin Schwidefsky #ifdef CONFIG_PGSTE 414527e30b4SMartin Schwidefsky gmap = (current->flags & PF_VCPU) ? 415527e30b4SMartin Schwidefsky (struct gmap *) S390_lowcore.gmap : NULL; 41624eb3a82SDominik Dingel if (gmap) { 417527e30b4SMartin Schwidefsky current->thread.gmap_addr = address; 418527e30b4SMartin Schwidefsky address = __gmap_translate(gmap, address); 419e5992f2eSMartin Schwidefsky if (address == -EFAULT) { 420e5992f2eSMartin Schwidefsky fault = VM_FAULT_BADMAP; 421e5992f2eSMartin Schwidefsky goto out_up; 422e5992f2eSMartin Schwidefsky } 42324eb3a82SDominik Dingel if (gmap->pfault_enabled) 42424eb3a82SDominik Dingel flags |= FAULT_FLAG_RETRY_NOWAIT; 425e5992f2eSMartin Schwidefsky } 426e5992f2eSMartin Schwidefsky #endif 427e5992f2eSMartin Schwidefsky 428e5992f2eSMartin Schwidefsky retry: 42950d7280dSMartin Schwidefsky fault = VM_FAULT_BADMAP; 4301da177e4SLinus Torvalds vma = find_vma(mm, address); 4311da177e4SLinus Torvalds if (!vma) 43250d7280dSMartin Schwidefsky goto out_up; 433c1821c2eSGerald Schaefer 43450d7280dSMartin Schwidefsky if (unlikely(vma->vm_start > address)) { 4351da177e4SLinus Torvalds if (!(vma->vm_flags & VM_GROWSDOWN)) 43650d7280dSMartin Schwidefsky goto out_up; 4371da177e4SLinus Torvalds if (expand_stack(vma, address)) 43850d7280dSMartin Schwidefsky goto out_up; 43950d7280dSMartin Schwidefsky } 44050d7280dSMartin Schwidefsky 4411da177e4SLinus Torvalds /* 4421da177e4SLinus Torvalds * Ok, we have a good vm_area for this memory access, so 4431da177e4SLinus Torvalds * we can handle it.. 4441da177e4SLinus Torvalds */ 44550d7280dSMartin Schwidefsky fault = VM_FAULT_BADACCESS; 4461ab947deSMartin Schwidefsky if (unlikely(!(vma->vm_flags & access))) 44750d7280dSMartin Schwidefsky goto out_up; 4481da177e4SLinus Torvalds 44953492b1dSGerald Schaefer if (is_vm_hugetlb_page(vma)) 45053492b1dSGerald Schaefer address &= HPAGE_MASK; 4511da177e4SLinus Torvalds /* 4521da177e4SLinus Torvalds * If for any reason at all we couldn't handle the fault, 4531da177e4SLinus Torvalds * make sure we exit gracefully rather than endlessly redo 4541da177e4SLinus Torvalds * the fault. 4551da177e4SLinus Torvalds */ 45633ce6140SHeiko Carstens fault = handle_mm_fault(mm, vma, address, flags); 457f2c76e3bSHeiko Carstens /* No reason to continue if interrupted by SIGKILL. */ 458f2c76e3bSHeiko Carstens if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) { 459f2c76e3bSHeiko Carstens fault = VM_FAULT_SIGNAL; 460f2c76e3bSHeiko Carstens goto out; 461f2c76e3bSHeiko Carstens } 46250d7280dSMartin Schwidefsky if (unlikely(fault & VM_FAULT_ERROR)) 46350d7280dSMartin Schwidefsky goto out_up; 46450d7280dSMartin Schwidefsky 46533ce6140SHeiko Carstens /* 46633ce6140SHeiko Carstens * Major/minor page fault accounting is only done on the 46733ce6140SHeiko Carstens * initial attempt. If we go through a retry, it is extremely 46833ce6140SHeiko Carstens * likely that the page will be found in page cache at that point. 46933ce6140SHeiko Carstens */ 47033ce6140SHeiko Carstens if (flags & FAULT_FLAG_ALLOW_RETRY) { 471bde69af2SHeiko Carstens if (fault & VM_FAULT_MAJOR) { 47283c54070SNick Piggin tsk->maj_flt++; 473a8b0ca17SPeter Zijlstra perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 474bde69af2SHeiko Carstens regs, address); 475bde69af2SHeiko Carstens } else { 47683c54070SNick Piggin tsk->min_flt++; 477a8b0ca17SPeter Zijlstra perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 478bde69af2SHeiko Carstens regs, address); 479bde69af2SHeiko Carstens } 48033ce6140SHeiko Carstens if (fault & VM_FAULT_RETRY) { 48124eb3a82SDominik Dingel #ifdef CONFIG_PGSTE 48224eb3a82SDominik Dingel if (gmap && (flags & FAULT_FLAG_RETRY_NOWAIT)) { 48324eb3a82SDominik Dingel /* FAULT_FLAG_RETRY_NOWAIT has been set, 48424eb3a82SDominik Dingel * mmap_sem has not been released */ 48524eb3a82SDominik Dingel current->thread.gmap_pfault = 1; 48624eb3a82SDominik Dingel fault = VM_FAULT_PFAULT; 48724eb3a82SDominik Dingel goto out_up; 48824eb3a82SDominik Dingel } 48924eb3a82SDominik Dingel #endif 49033ce6140SHeiko Carstens /* Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk 49133ce6140SHeiko Carstens * of starvation. */ 49224eb3a82SDominik Dingel flags &= ~(FAULT_FLAG_ALLOW_RETRY | 49324eb3a82SDominik Dingel FAULT_FLAG_RETRY_NOWAIT); 49445cac65bSShaohua Li flags |= FAULT_FLAG_TRIED; 495e5992f2eSMartin Schwidefsky down_read(&mm->mmap_sem); 49633ce6140SHeiko Carstens goto retry; 49733ce6140SHeiko Carstens } 49833ce6140SHeiko Carstens } 499527e30b4SMartin Schwidefsky #ifdef CONFIG_PGSTE 500527e30b4SMartin Schwidefsky if (gmap) { 501527e30b4SMartin Schwidefsky address = __gmap_link(gmap, current->thread.gmap_addr, 502527e30b4SMartin Schwidefsky address); 503527e30b4SMartin Schwidefsky if (address == -EFAULT) { 504527e30b4SMartin Schwidefsky fault = VM_FAULT_BADMAP; 505527e30b4SMartin Schwidefsky goto out_up; 506527e30b4SMartin Schwidefsky } 507527e30b4SMartin Schwidefsky if (address == -ENOMEM) { 508527e30b4SMartin Schwidefsky fault = VM_FAULT_OOM; 509527e30b4SMartin Schwidefsky goto out_up; 510527e30b4SMartin Schwidefsky } 511527e30b4SMartin Schwidefsky } 512527e30b4SMartin Schwidefsky #endif 51350d7280dSMartin Schwidefsky fault = 0; 51450d7280dSMartin Schwidefsky out_up: 5151da177e4SLinus Torvalds up_read(&mm->mmap_sem); 51650d7280dSMartin Schwidefsky out: 51750d7280dSMartin Schwidefsky return fault; 5181da177e4SLinus Torvalds } 5191da177e4SLinus Torvalds 5207a5388deSHeiko Carstens void do_protection_exception(struct pt_regs *regs) 5211da177e4SLinus Torvalds { 522aa33c8cbSMartin Schwidefsky unsigned long trans_exc_code; 52350d7280dSMartin Schwidefsky int fault; 52461365e13SMartin Schwidefsky 525aa33c8cbSMartin Schwidefsky trans_exc_code = regs->int_parm_long; 526f752ac4dSMartin Schwidefsky /* 527f752ac4dSMartin Schwidefsky * Protection exceptions are suppressing, decrement psw address. 528f752ac4dSMartin Schwidefsky * The exception to this rule are aborted transactions, for these 529f752ac4dSMartin Schwidefsky * the PSW already points to the correct location. 530f752ac4dSMartin Schwidefsky */ 531f752ac4dSMartin Schwidefsky if (!(regs->int_code & 0x200)) 532aa33c8cbSMartin Schwidefsky regs->psw.addr = __rewind_psw(regs->psw, regs->int_code >> 16); 53310c1031fSMartin Schwidefsky /* 53410c1031fSMartin Schwidefsky * Check for low-address protection. This needs to be treated 53510c1031fSMartin Schwidefsky * as a special case because the translation exception code 53610c1031fSMartin Schwidefsky * field is not guaranteed to contain valid data in this case. 53710c1031fSMartin Schwidefsky */ 53861365e13SMartin Schwidefsky if (unlikely(!(trans_exc_code & 4))) { 539aa33c8cbSMartin Schwidefsky do_low_address(regs); 54010c1031fSMartin Schwidefsky return; 54110c1031fSMartin Schwidefsky } 542aa33c8cbSMartin Schwidefsky fault = do_exception(regs, VM_WRITE); 54350d7280dSMartin Schwidefsky if (unlikely(fault)) 544aa33c8cbSMartin Schwidefsky do_fault_error(regs, fault); 5451da177e4SLinus Torvalds } 5467a5388deSHeiko Carstens NOKPROBE_SYMBOL(do_protection_exception); 5471da177e4SLinus Torvalds 5487a5388deSHeiko Carstens void do_dat_exception(struct pt_regs *regs) 5491da177e4SLinus Torvalds { 5501ab947deSMartin Schwidefsky int access, fault; 55150d7280dSMartin Schwidefsky 5521ab947deSMartin Schwidefsky access = VM_READ | VM_EXEC | VM_WRITE; 553aa33c8cbSMartin Schwidefsky fault = do_exception(regs, access); 55450d7280dSMartin Schwidefsky if (unlikely(fault)) 555aa33c8cbSMartin Schwidefsky do_fault_error(regs, fault); 5561da177e4SLinus Torvalds } 5577a5388deSHeiko Carstens NOKPROBE_SYMBOL(do_dat_exception); 5581da177e4SLinus Torvalds 5591da177e4SLinus Torvalds #ifdef CONFIG_PFAULT 5601da177e4SLinus Torvalds /* 5611da177e4SLinus Torvalds * 'pfault' pseudo page faults routines. 5621da177e4SLinus Torvalds */ 563fb0a9d7eSHeiko Carstens static int pfault_disable; 5641da177e4SLinus Torvalds 5651da177e4SLinus Torvalds static int __init nopfault(char *str) 5661da177e4SLinus Torvalds { 5671da177e4SLinus Torvalds pfault_disable = 1; 5681da177e4SLinus Torvalds return 1; 5691da177e4SLinus Torvalds } 5701da177e4SLinus Torvalds 5711da177e4SLinus Torvalds __setup("nopfault", nopfault); 5721da177e4SLinus Torvalds 5737dd8fe1fSHeiko Carstens struct pfault_refbk { 5747dd8fe1fSHeiko Carstens u16 refdiagc; 5757dd8fe1fSHeiko Carstens u16 reffcode; 5767dd8fe1fSHeiko Carstens u16 refdwlen; 5777dd8fe1fSHeiko Carstens u16 refversn; 5787dd8fe1fSHeiko Carstens u64 refgaddr; 5797dd8fe1fSHeiko Carstens u64 refselmk; 5807dd8fe1fSHeiko Carstens u64 refcmpmk; 5817dd8fe1fSHeiko Carstens u64 reserved; 5827dd8fe1fSHeiko Carstens } __attribute__ ((packed, aligned(8))); 5831da177e4SLinus Torvalds 5841da177e4SLinus Torvalds int pfault_init(void) 5851da177e4SLinus Torvalds { 5867dd8fe1fSHeiko Carstens struct pfault_refbk refbk = { 5877dd8fe1fSHeiko Carstens .refdiagc = 0x258, 5887dd8fe1fSHeiko Carstens .reffcode = 0, 5897dd8fe1fSHeiko Carstens .refdwlen = 5, 5907dd8fe1fSHeiko Carstens .refversn = 2, 591e22cf8caSChristian Borntraeger .refgaddr = __LC_LPP, 5927dd8fe1fSHeiko Carstens .refselmk = 1ULL << 48, 5937dd8fe1fSHeiko Carstens .refcmpmk = 1ULL << 48, 5947dd8fe1fSHeiko Carstens .reserved = __PF_RES_FIELD }; 5951da177e4SLinus Torvalds int rc; 5961da177e4SLinus Torvalds 597f32269a0SCarsten Otte if (pfault_disable) 5981da177e4SLinus Torvalds return -1; 5991ec2772eSMartin Schwidefsky diag_stat_inc(DIAG_STAT_X258); 60094c12cc7SMartin Schwidefsky asm volatile( 6011da177e4SLinus Torvalds " diag %1,%0,0x258\n" 6021da177e4SLinus Torvalds "0: j 2f\n" 6031da177e4SLinus Torvalds "1: la %0,8\n" 6041da177e4SLinus Torvalds "2:\n" 60594c12cc7SMartin Schwidefsky EX_TABLE(0b,1b) 606d4b68996SMartin Schwidefsky : "=d" (rc) : "a" (&refbk), "m" (refbk) : "cc"); 6071da177e4SLinus Torvalds return rc; 6081da177e4SLinus Torvalds } 6091da177e4SLinus Torvalds 6101da177e4SLinus Torvalds void pfault_fini(void) 6111da177e4SLinus Torvalds { 6127dd8fe1fSHeiko Carstens struct pfault_refbk refbk = { 6137dd8fe1fSHeiko Carstens .refdiagc = 0x258, 6147dd8fe1fSHeiko Carstens .reffcode = 1, 6157dd8fe1fSHeiko Carstens .refdwlen = 5, 6167dd8fe1fSHeiko Carstens .refversn = 2, 6177dd8fe1fSHeiko Carstens }; 6181da177e4SLinus Torvalds 619f32269a0SCarsten Otte if (pfault_disable) 6201da177e4SLinus Torvalds return; 6211ec2772eSMartin Schwidefsky diag_stat_inc(DIAG_STAT_X258); 62294c12cc7SMartin Schwidefsky asm volatile( 6231da177e4SLinus Torvalds " diag %0,0,0x258\n" 6241da177e4SLinus Torvalds "0:\n" 62594c12cc7SMartin Schwidefsky EX_TABLE(0b,0b) 626d4b68996SMartin Schwidefsky : : "a" (&refbk), "m" (refbk) : "cc"); 6271da177e4SLinus Torvalds } 6281da177e4SLinus Torvalds 629f2db2e6cSHeiko Carstens static DEFINE_SPINLOCK(pfault_lock); 630f2db2e6cSHeiko Carstens static LIST_HEAD(pfault_list); 631f2db2e6cSHeiko Carstens 632fde15c3aSHeiko Carstens static void pfault_interrupt(struct ext_code ext_code, 633f6649a7eSMartin Schwidefsky unsigned int param32, unsigned long param64) 6341da177e4SLinus Torvalds { 6351da177e4SLinus Torvalds struct task_struct *tsk; 6361da177e4SLinus Torvalds __u16 subcode; 637f2db2e6cSHeiko Carstens pid_t pid; 6381da177e4SLinus Torvalds 6391da177e4SLinus Torvalds /* 6401da177e4SLinus Torvalds * Get the external interruption subcode & pfault 6411da177e4SLinus Torvalds * initial/completion signal bit. VM stores this 6421da177e4SLinus Torvalds * in the 'cpu address' field associated with the 6431da177e4SLinus Torvalds * external interrupt. 6441da177e4SLinus Torvalds */ 645fde15c3aSHeiko Carstens subcode = ext_code.subcode; 6461da177e4SLinus Torvalds if ((subcode & 0xff00) != __SUBCODE_MASK) 6471da177e4SLinus Torvalds return; 648420f42ecSHeiko Carstens inc_irq_stat(IRQEXT_PFL); 649f2db2e6cSHeiko Carstens /* Get the token (= pid of the affected task). */ 650e22cf8caSChristian Borntraeger pid = param64 & LPP_PFAULT_PID_MASK; 651f2db2e6cSHeiko Carstens rcu_read_lock(); 652f2db2e6cSHeiko Carstens tsk = find_task_by_pid_ns(pid, &init_pid_ns); 653f2db2e6cSHeiko Carstens if (tsk) 654f2db2e6cSHeiko Carstens get_task_struct(tsk); 655f2db2e6cSHeiko Carstens rcu_read_unlock(); 656f2db2e6cSHeiko Carstens if (!tsk) 657f2db2e6cSHeiko Carstens return; 658f2db2e6cSHeiko Carstens spin_lock(&pfault_lock); 6591da177e4SLinus Torvalds if (subcode & 0x0080) { 6601da177e4SLinus Torvalds /* signal bit is set -> a page has been swapped in by VM */ 661f2db2e6cSHeiko Carstens if (tsk->thread.pfault_wait == 1) { 6621da177e4SLinus Torvalds /* Initial interrupt was faster than the completion 6631da177e4SLinus Torvalds * interrupt. pfault_wait is valid. Set pfault_wait 6641da177e4SLinus Torvalds * back to zero and wake up the process. This can 6651da177e4SLinus Torvalds * safely be done because the task is still sleeping 666b6d09449SMartin Schwidefsky * and can't produce new pfaults. */ 6671da177e4SLinus Torvalds tsk->thread.pfault_wait = 0; 668f2db2e6cSHeiko Carstens list_del(&tsk->thread.list); 6691da177e4SLinus Torvalds wake_up_process(tsk); 670d5e50a51SHeiko Carstens put_task_struct(tsk); 671f2db2e6cSHeiko Carstens } else { 672f2db2e6cSHeiko Carstens /* Completion interrupt was faster than initial 673f2db2e6cSHeiko Carstens * interrupt. Set pfault_wait to -1 so the initial 674fa2fb2f4SHeiko Carstens * interrupt doesn't put the task to sleep. 675fa2fb2f4SHeiko Carstens * If the task is not running, ignore the completion 676fa2fb2f4SHeiko Carstens * interrupt since it must be a leftover of a PFAULT 677fa2fb2f4SHeiko Carstens * CANCEL operation which didn't remove all pending 678fa2fb2f4SHeiko Carstens * completion interrupts. */ 679fa2fb2f4SHeiko Carstens if (tsk->state == TASK_RUNNING) 680f2db2e6cSHeiko Carstens tsk->thread.pfault_wait = -1; 6811da177e4SLinus Torvalds } 6821da177e4SLinus Torvalds } else { 6831da177e4SLinus Torvalds /* signal bit not set -> a real page is missing. */ 684d49f47f8SHeiko Carstens if (WARN_ON_ONCE(tsk != current)) 685d49f47f8SHeiko Carstens goto out; 686d5e50a51SHeiko Carstens if (tsk->thread.pfault_wait == 1) { 687d5e50a51SHeiko Carstens /* Already on the list with a reference: put to sleep */ 6880a16ba78SHeiko Carstens __set_task_state(tsk, TASK_UNINTERRUPTIBLE); 689d5e50a51SHeiko Carstens set_tsk_need_resched(tsk); 690d5e50a51SHeiko Carstens } else if (tsk->thread.pfault_wait == -1) { 6911da177e4SLinus Torvalds /* Completion interrupt was faster than the initial 692f2db2e6cSHeiko Carstens * interrupt (pfault_wait == -1). Set pfault_wait 693f2db2e6cSHeiko Carstens * back to zero and exit. */ 6941da177e4SLinus Torvalds tsk->thread.pfault_wait = 0; 695f2db2e6cSHeiko Carstens } else { 696f2db2e6cSHeiko Carstens /* Initial interrupt arrived before completion 697d5e50a51SHeiko Carstens * interrupt. Let the task sleep. 698d5e50a51SHeiko Carstens * An extra task reference is needed since a different 699d5e50a51SHeiko Carstens * cpu may set the task state to TASK_RUNNING again 700d5e50a51SHeiko Carstens * before the scheduler is reached. */ 701d5e50a51SHeiko Carstens get_task_struct(tsk); 702f2db2e6cSHeiko Carstens tsk->thread.pfault_wait = 1; 703f2db2e6cSHeiko Carstens list_add(&tsk->thread.list, &pfault_list); 7040a16ba78SHeiko Carstens __set_task_state(tsk, TASK_UNINTERRUPTIBLE); 7051da177e4SLinus Torvalds set_tsk_need_resched(tsk); 7061da177e4SLinus Torvalds } 7071da177e4SLinus Torvalds } 708d49f47f8SHeiko Carstens out: 709f2db2e6cSHeiko Carstens spin_unlock(&pfault_lock); 71054c27791SHeiko Carstens put_task_struct(tsk); 711f2db2e6cSHeiko Carstens } 712f2db2e6cSHeiko Carstens 713e2741f17SPaul Gortmaker static int pfault_cpu_notify(struct notifier_block *self, unsigned long action, 714e2741f17SPaul Gortmaker void *hcpu) 715f2db2e6cSHeiko Carstens { 716f2db2e6cSHeiko Carstens struct thread_struct *thread, *next; 717f2db2e6cSHeiko Carstens struct task_struct *tsk; 718f2db2e6cSHeiko Carstens 7191c725922SHeiko Carstens switch (action & ~CPU_TASKS_FROZEN) { 720f2db2e6cSHeiko Carstens case CPU_DEAD: 721f2db2e6cSHeiko Carstens spin_lock_irq(&pfault_lock); 722f2db2e6cSHeiko Carstens list_for_each_entry_safe(thread, next, &pfault_list, list) { 723f2db2e6cSHeiko Carstens thread->pfault_wait = 0; 724f2db2e6cSHeiko Carstens list_del(&thread->list); 725f2db2e6cSHeiko Carstens tsk = container_of(thread, struct task_struct, thread); 726f2db2e6cSHeiko Carstens wake_up_process(tsk); 727d5e50a51SHeiko Carstens put_task_struct(tsk); 728f2db2e6cSHeiko Carstens } 729f2db2e6cSHeiko Carstens spin_unlock_irq(&pfault_lock); 730f2db2e6cSHeiko Carstens break; 731f2db2e6cSHeiko Carstens default: 732f2db2e6cSHeiko Carstens break; 733f2db2e6cSHeiko Carstens } 734f2db2e6cSHeiko Carstens return NOTIFY_OK; 735f2db2e6cSHeiko Carstens } 7361da177e4SLinus Torvalds 737fb0a9d7eSHeiko Carstens static int __init pfault_irq_init(void) 73829b08d2bSHeiko Carstens { 739fb0a9d7eSHeiko Carstens int rc; 74029b08d2bSHeiko Carstens 7411dad093bSThomas Huth rc = register_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt); 7427dd8fe1fSHeiko Carstens if (rc) 7437dd8fe1fSHeiko Carstens goto out_extint; 7447dd8fe1fSHeiko Carstens rc = pfault_init() == 0 ? 0 : -EOPNOTSUPP; 7457dd8fe1fSHeiko Carstens if (rc) 7467dd8fe1fSHeiko Carstens goto out_pfault; 74782003c3eSHeiko Carstens irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL); 7487dd8fe1fSHeiko Carstens hotcpu_notifier(pfault_cpu_notify, 0); 7497dd8fe1fSHeiko Carstens return 0; 7507dd8fe1fSHeiko Carstens 7517dd8fe1fSHeiko Carstens out_pfault: 7521dad093bSThomas Huth unregister_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt); 7537dd8fe1fSHeiko Carstens out_extint: 754fb0a9d7eSHeiko Carstens pfault_disable = 1; 755fb0a9d7eSHeiko Carstens return rc; 756fb0a9d7eSHeiko Carstens } 757fb0a9d7eSHeiko Carstens early_initcall(pfault_irq_init); 758fb0a9d7eSHeiko Carstens 7597dd8fe1fSHeiko Carstens #endif /* CONFIG_PFAULT */ 760