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> 35*1e133ab2SMartin Schwidefsky #include <asm/gmap.h> 36d7b250e2SHeiko Carstens #include <asm/irq.h> 376252d702SMartin Schwidefsky #include <asm/mmu_context.h> 38a0616cdeSDavid Howells #include <asm/facility.h> 39a806170eSHeiko Carstens #include "../kernel/entry.h" 401da177e4SLinus Torvalds 411da177e4SLinus Torvalds #define __FAIL_ADDR_MASK -4096L 421da177e4SLinus Torvalds #define __SUBCODE_MASK 0x0600 431da177e4SLinus Torvalds #define __PF_RES_FIELD 0x8000000000000000ULL 441da177e4SLinus Torvalds 4550d7280dSMartin Schwidefsky #define VM_FAULT_BADCONTEXT 0x010000 4650d7280dSMartin Schwidefsky #define VM_FAULT_BADMAP 0x020000 4750d7280dSMartin Schwidefsky #define VM_FAULT_BADACCESS 0x040000 48f2c76e3bSHeiko Carstens #define VM_FAULT_SIGNAL 0x080000 4924eb3a82SDominik Dingel #define VM_FAULT_PFAULT 0x100000 5050d7280dSMartin Schwidefsky 51a4f32bdbSHeiko Carstens static unsigned long store_indication __read_mostly; 5292f842eaSMartin Schwidefsky 53a4f32bdbSHeiko Carstens static int __init fault_init(void) 5492f842eaSMartin Schwidefsky { 55a4f32bdbSHeiko Carstens if (test_facility(75)) 5692f842eaSMartin Schwidefsky store_indication = 0xc00; 57a4f32bdbSHeiko Carstens return 0; 5892f842eaSMartin Schwidefsky } 59a4f32bdbSHeiko Carstens early_initcall(fault_init); 6092f842eaSMartin Schwidefsky 617ecb344aSMartin Schwidefsky static inline int notify_page_fault(struct pt_regs *regs) 6210c1031fSMartin Schwidefsky { 6333464e3bSChristoph Hellwig int ret = 0; 6433464e3bSChristoph Hellwig 6533464e3bSChristoph Hellwig /* kprobe_running() needs smp_processor_id() */ 6622e0a046SHeiko Carstens if (kprobes_built_in() && !user_mode(regs)) { 6733464e3bSChristoph Hellwig preempt_disable(); 6833464e3bSChristoph Hellwig if (kprobe_running() && kprobe_fault_handler(regs, 14)) 6933464e3bSChristoph Hellwig ret = 1; 7033464e3bSChristoph Hellwig preempt_enable(); 7133464e3bSChristoph Hellwig } 7233464e3bSChristoph Hellwig return ret; 734ba069b8SMichael Grundy } 744ba069b8SMichael Grundy 751da177e4SLinus Torvalds 761da177e4SLinus Torvalds /* 771da177e4SLinus Torvalds * Unlock any spinlocks which will prevent us from getting the 78cefc8be8SKirill Korotaev * message out. 791da177e4SLinus Torvalds */ 801da177e4SLinus Torvalds void bust_spinlocks(int yes) 811da177e4SLinus Torvalds { 821da177e4SLinus Torvalds if (yes) { 831da177e4SLinus Torvalds oops_in_progress = 1; 841da177e4SLinus Torvalds } else { 851da177e4SLinus Torvalds int loglevel_save = console_loglevel; 861da177e4SLinus Torvalds console_unblank(); 871da177e4SLinus Torvalds oops_in_progress = 0; 881da177e4SLinus Torvalds /* 891da177e4SLinus Torvalds * OK, the message is on the console. Now we call printk() 901da177e4SLinus Torvalds * without oops_in_progress set so that printk will give klogd 911da177e4SLinus Torvalds * a poke. Hold onto your hats... 921da177e4SLinus Torvalds */ 931da177e4SLinus Torvalds console_loglevel = 15; 941da177e4SLinus Torvalds printk(" "); 951da177e4SLinus Torvalds console_loglevel = loglevel_save; 961da177e4SLinus Torvalds } 971da177e4SLinus Torvalds } 981da177e4SLinus Torvalds 991da177e4SLinus Torvalds /* 100482b05ddSGerald Schaefer * Returns the address space associated with the fault. 10161365e13SMartin Schwidefsky * Returns 0 for kernel space and 1 for user space. 1021da177e4SLinus Torvalds */ 103457f2180SHeiko Carstens static inline int user_space_fault(struct pt_regs *regs) 1041da177e4SLinus Torvalds { 105457f2180SHeiko Carstens unsigned long trans_exc_code; 106457f2180SHeiko Carstens 1071da177e4SLinus Torvalds /* 10861365e13SMartin Schwidefsky * The lowest two bits of the translation exception 10961365e13SMartin Schwidefsky * identification indicate which paging table was used. 1101da177e4SLinus Torvalds */ 111457f2180SHeiko Carstens trans_exc_code = regs->int_parm_long & 3; 112457f2180SHeiko Carstens if (trans_exc_code == 3) /* home space -> kernel */ 113457f2180SHeiko Carstens return 0; 114457f2180SHeiko Carstens if (user_mode(regs)) 115457f2180SHeiko Carstens return 1; 116457f2180SHeiko Carstens if (trans_exc_code == 2) /* secondary space -> set_fs */ 11761365e13SMartin Schwidefsky return current->thread.mm_segment.ar4; 118457f2180SHeiko Carstens if (current->flags & PF_VCPU) 119457f2180SHeiko Carstens return 1; 120457f2180SHeiko Carstens return 0; 1211da177e4SLinus Torvalds } 1221da177e4SLinus Torvalds 1233b7df342SHeiko Carstens static int bad_address(void *p) 1243b7df342SHeiko Carstens { 1253b7df342SHeiko Carstens unsigned long dummy; 1263b7df342SHeiko Carstens 1273b7df342SHeiko Carstens return probe_kernel_address((unsigned long *)p, dummy); 1283b7df342SHeiko Carstens } 1293b7df342SHeiko Carstens 1303b7df342SHeiko Carstens static void dump_pagetable(unsigned long asce, unsigned long address) 1313b7df342SHeiko Carstens { 1323b7df342SHeiko Carstens unsigned long *table = __va(asce & PAGE_MASK); 1333b7df342SHeiko Carstens 1343b7df342SHeiko Carstens pr_alert("AS:%016lx ", asce); 1353b7df342SHeiko Carstens switch (asce & _ASCE_TYPE_MASK) { 1363b7df342SHeiko Carstens case _ASCE_TYPE_REGION1: 1373b7df342SHeiko Carstens table = table + ((address >> 53) & 0x7ff); 1383b7df342SHeiko Carstens if (bad_address(table)) 1393b7df342SHeiko Carstens goto bad; 1403b7df342SHeiko Carstens pr_cont("R1:%016lx ", *table); 1413b7df342SHeiko Carstens if (*table & _REGION_ENTRY_INVALID) 1423b7df342SHeiko Carstens goto out; 1433b7df342SHeiko Carstens table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); 1443b7df342SHeiko Carstens /* fallthrough */ 1453b7df342SHeiko Carstens case _ASCE_TYPE_REGION2: 1463b7df342SHeiko Carstens table = table + ((address >> 42) & 0x7ff); 1473b7df342SHeiko Carstens if (bad_address(table)) 1483b7df342SHeiko Carstens goto bad; 1493b7df342SHeiko Carstens pr_cont("R2:%016lx ", *table); 1503b7df342SHeiko Carstens if (*table & _REGION_ENTRY_INVALID) 1513b7df342SHeiko Carstens goto out; 1523b7df342SHeiko Carstens table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); 1533b7df342SHeiko Carstens /* fallthrough */ 1543b7df342SHeiko Carstens case _ASCE_TYPE_REGION3: 1553b7df342SHeiko Carstens table = table + ((address >> 31) & 0x7ff); 1563b7df342SHeiko Carstens if (bad_address(table)) 1573b7df342SHeiko Carstens goto bad; 1583b7df342SHeiko Carstens pr_cont("R3:%016lx ", *table); 1593b7df342SHeiko Carstens if (*table & (_REGION_ENTRY_INVALID | _REGION3_ENTRY_LARGE)) 1603b7df342SHeiko Carstens goto out; 1613b7df342SHeiko Carstens table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); 1623b7df342SHeiko Carstens /* fallthrough */ 1633b7df342SHeiko Carstens case _ASCE_TYPE_SEGMENT: 1643b7df342SHeiko Carstens table = table + ((address >> 20) & 0x7ff); 1653b7df342SHeiko Carstens if (bad_address(table)) 1663b7df342SHeiko Carstens goto bad; 16791c0837eSJoe Perches pr_cont("S:%016lx ", *table); 1683b7df342SHeiko Carstens if (*table & (_SEGMENT_ENTRY_INVALID | _SEGMENT_ENTRY_LARGE)) 1693b7df342SHeiko Carstens goto out; 1703b7df342SHeiko Carstens table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN); 1713b7df342SHeiko Carstens } 1723b7df342SHeiko Carstens table = table + ((address >> 12) & 0xff); 1733b7df342SHeiko Carstens if (bad_address(table)) 1743b7df342SHeiko Carstens goto bad; 1753b7df342SHeiko Carstens pr_cont("P:%016lx ", *table); 1763b7df342SHeiko Carstens out: 1773b7df342SHeiko Carstens pr_cont("\n"); 1783b7df342SHeiko Carstens return; 1793b7df342SHeiko Carstens bad: 1803b7df342SHeiko Carstens pr_cont("BAD\n"); 1813b7df342SHeiko Carstens } 1823b7df342SHeiko Carstens 1833b7df342SHeiko Carstens static void dump_fault_info(struct pt_regs *regs) 1843b7df342SHeiko Carstens { 1853b7df342SHeiko Carstens unsigned long asce; 1863b7df342SHeiko Carstens 1875d7eccecSHeiko Carstens pr_alert("Failing address: %016lx TEID: %016lx\n", 1885d7eccecSHeiko Carstens regs->int_parm_long & __FAIL_ADDR_MASK, regs->int_parm_long); 1893b7df342SHeiko Carstens pr_alert("Fault in "); 1903b7df342SHeiko Carstens switch (regs->int_parm_long & 3) { 1913b7df342SHeiko Carstens case 3: 1923b7df342SHeiko Carstens pr_cont("home space "); 1933b7df342SHeiko Carstens break; 1943b7df342SHeiko Carstens case 2: 1953b7df342SHeiko Carstens pr_cont("secondary space "); 1963b7df342SHeiko Carstens break; 1973b7df342SHeiko Carstens case 1: 1983b7df342SHeiko Carstens pr_cont("access register "); 1993b7df342SHeiko Carstens break; 2003b7df342SHeiko Carstens case 0: 2013b7df342SHeiko Carstens pr_cont("primary space "); 2023b7df342SHeiko Carstens break; 2033b7df342SHeiko Carstens } 2043b7df342SHeiko Carstens pr_cont("mode while using "); 2053b7df342SHeiko Carstens if (!user_space_fault(regs)) { 2063b7df342SHeiko Carstens asce = S390_lowcore.kernel_asce; 2073b7df342SHeiko Carstens pr_cont("kernel "); 2083b7df342SHeiko Carstens } 2093b7df342SHeiko Carstens #ifdef CONFIG_PGSTE 2103b7df342SHeiko Carstens else if ((current->flags & PF_VCPU) && S390_lowcore.gmap) { 2113b7df342SHeiko Carstens struct gmap *gmap = (struct gmap *)S390_lowcore.gmap; 2123b7df342SHeiko Carstens asce = gmap->asce; 2133b7df342SHeiko Carstens pr_cont("gmap "); 2143b7df342SHeiko Carstens } 2153b7df342SHeiko Carstens #endif 2163b7df342SHeiko Carstens else { 2173b7df342SHeiko Carstens asce = S390_lowcore.user_asce; 2183b7df342SHeiko Carstens pr_cont("user "); 2193b7df342SHeiko Carstens } 2203b7df342SHeiko Carstens pr_cont("ASCE.\n"); 2213b7df342SHeiko Carstens dump_pagetable(asce, regs->int_parm_long & __FAIL_ADDR_MASK); 2223b7df342SHeiko Carstens } 2233b7df342SHeiko Carstens 2245d7eccecSHeiko Carstens int show_unhandled_signals = 1; 2255d7eccecSHeiko Carstens 2265d7eccecSHeiko Carstens void report_user_fault(struct pt_regs *regs, long signr, int is_mm_fault) 227ab3c68eeSHeiko Carstens { 228ab3c68eeSHeiko Carstens if ((task_pid_nr(current) > 1) && !show_unhandled_signals) 229ab3c68eeSHeiko Carstens return; 230ab3c68eeSHeiko Carstens if (!unhandled_signal(current, signr)) 231ab3c68eeSHeiko Carstens return; 232ab3c68eeSHeiko Carstens if (!printk_ratelimit()) 233ab3c68eeSHeiko Carstens return; 234413d4047SHeiko Carstens printk(KERN_ALERT "User process fault: interruption code %04x ilc:%d ", 235413d4047SHeiko Carstens regs->int_code & 0xffff, regs->int_code >> 17); 2369cb1ccecSHeiko Carstens print_vma_addr(KERN_CONT "in ", regs->psw.addr); 237aa33c8cbSMartin Schwidefsky printk(KERN_CONT "\n"); 2385d7eccecSHeiko Carstens if (is_mm_fault) 2393b7df342SHeiko Carstens dump_fault_info(regs); 240ab3c68eeSHeiko Carstens show_regs(regs); 241ab3c68eeSHeiko Carstens } 242ab3c68eeSHeiko Carstens 2431da177e4SLinus Torvalds /* 2441da177e4SLinus Torvalds * Send SIGSEGV to task. This is an external routine 2451da177e4SLinus Torvalds * to keep the stack usage of do_page_fault small. 2461da177e4SLinus Torvalds */ 247aa33c8cbSMartin Schwidefsky static noinline void do_sigsegv(struct pt_regs *regs, int si_code) 2481da177e4SLinus Torvalds { 2491da177e4SLinus Torvalds struct siginfo si; 2501da177e4SLinus Torvalds 2515d7eccecSHeiko Carstens report_user_fault(regs, SIGSEGV, 1); 2521da177e4SLinus Torvalds si.si_signo = SIGSEGV; 2531da177e4SLinus Torvalds si.si_code = si_code; 254aa33c8cbSMartin Schwidefsky si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK); 2551da177e4SLinus Torvalds force_sig_info(SIGSEGV, &si, current); 2561da177e4SLinus Torvalds } 2571da177e4SLinus Torvalds 258aa33c8cbSMartin Schwidefsky static noinline void do_no_context(struct pt_regs *regs) 25910c1031fSMartin Schwidefsky { 26010c1031fSMartin Schwidefsky const struct exception_table_entry *fixup; 26110c1031fSMartin Schwidefsky 26210c1031fSMartin Schwidefsky /* Are we prepared to handle this kernel fault? */ 2639cb1ccecSHeiko Carstens fixup = search_exception_tables(regs->psw.addr); 26410c1031fSMartin Schwidefsky if (fixup) { 265fecc868aSHeiko Carstens regs->psw.addr = extable_fixup(fixup); 26610c1031fSMartin Schwidefsky return; 26710c1031fSMartin Schwidefsky } 26810c1031fSMartin Schwidefsky 26910c1031fSMartin Schwidefsky /* 27010c1031fSMartin Schwidefsky * Oops. The kernel tried to access some bad page. We'll have to 27110c1031fSMartin Schwidefsky * terminate things with extreme prejudice. 27210c1031fSMartin Schwidefsky */ 273457f2180SHeiko Carstens if (!user_space_fault(regs)) 27410c1031fSMartin Schwidefsky printk(KERN_ALERT "Unable to handle kernel pointer dereference" 2753b7df342SHeiko Carstens " in virtual kernel address space\n"); 27610c1031fSMartin Schwidefsky else 27710c1031fSMartin Schwidefsky printk(KERN_ALERT "Unable to handle kernel paging request" 2783b7df342SHeiko Carstens " in virtual user address space\n"); 2793b7df342SHeiko Carstens dump_fault_info(regs); 280aa33c8cbSMartin Schwidefsky die(regs, "Oops"); 28110c1031fSMartin Schwidefsky do_exit(SIGKILL); 28210c1031fSMartin Schwidefsky } 28310c1031fSMartin Schwidefsky 284aa33c8cbSMartin Schwidefsky static noinline void do_low_address(struct pt_regs *regs) 28510c1031fSMartin Schwidefsky { 28610c1031fSMartin Schwidefsky /* Low-address protection hit in kernel mode means 28710c1031fSMartin Schwidefsky NULL pointer write access in kernel mode. */ 28810c1031fSMartin Schwidefsky if (regs->psw.mask & PSW_MASK_PSTATE) { 28910c1031fSMartin Schwidefsky /* Low-address protection hit in user mode 'cannot happen'. */ 290aa33c8cbSMartin Schwidefsky die (regs, "Low-address protection"); 29110c1031fSMartin Schwidefsky do_exit(SIGKILL); 29210c1031fSMartin Schwidefsky } 29310c1031fSMartin Schwidefsky 294aa33c8cbSMartin Schwidefsky do_no_context(regs); 29510c1031fSMartin Schwidefsky } 29610c1031fSMartin Schwidefsky 297aa33c8cbSMartin Schwidefsky static noinline void do_sigbus(struct pt_regs *regs) 29810c1031fSMartin Schwidefsky { 29910c1031fSMartin Schwidefsky struct task_struct *tsk = current; 30036bf9680SMartin Schwidefsky struct siginfo si; 30110c1031fSMartin Schwidefsky 30210c1031fSMartin Schwidefsky /* 30310c1031fSMartin Schwidefsky * Send a sigbus, regardless of whether we were in kernel 30410c1031fSMartin Schwidefsky * or user mode. 30510c1031fSMartin Schwidefsky */ 30636bf9680SMartin Schwidefsky si.si_signo = SIGBUS; 30736bf9680SMartin Schwidefsky si.si_errno = 0; 30836bf9680SMartin Schwidefsky si.si_code = BUS_ADRERR; 309aa33c8cbSMartin Schwidefsky si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK); 31036bf9680SMartin Schwidefsky force_sig_info(SIGBUS, &si, tsk); 31110c1031fSMartin Schwidefsky } 31210c1031fSMartin Schwidefsky 313aa33c8cbSMartin Schwidefsky static noinline void do_fault_error(struct pt_regs *regs, int fault) 31450d7280dSMartin Schwidefsky { 31550d7280dSMartin Schwidefsky int si_code; 31650d7280dSMartin Schwidefsky 31750d7280dSMartin Schwidefsky switch (fault) { 31850d7280dSMartin Schwidefsky case VM_FAULT_BADACCESS: 31950d7280dSMartin Schwidefsky case VM_FAULT_BADMAP: 32050d7280dSMartin Schwidefsky /* Bad memory access. Check if it is kernel or user space. */ 3217d256175SHeiko Carstens if (user_mode(regs)) { 32250d7280dSMartin Schwidefsky /* User mode accesses just cause a SIGSEGV */ 32350d7280dSMartin Schwidefsky si_code = (fault == VM_FAULT_BADMAP) ? 32450d7280dSMartin Schwidefsky SEGV_MAPERR : SEGV_ACCERR; 325aa33c8cbSMartin Schwidefsky do_sigsegv(regs, si_code); 32650d7280dSMartin Schwidefsky return; 32750d7280dSMartin Schwidefsky } 32850d7280dSMartin Schwidefsky case VM_FAULT_BADCONTEXT: 32924eb3a82SDominik Dingel case VM_FAULT_PFAULT: 330aa33c8cbSMartin Schwidefsky do_no_context(regs); 33150d7280dSMartin Schwidefsky break; 332f2c76e3bSHeiko Carstens case VM_FAULT_SIGNAL: 333f2c76e3bSHeiko Carstens if (!user_mode(regs)) 334f2c76e3bSHeiko Carstens do_no_context(regs); 335f2c76e3bSHeiko Carstens break; 33650d7280dSMartin Schwidefsky default: /* fault & VM_FAULT_ERROR */ 33799583181SHeiko Carstens if (fault & VM_FAULT_OOM) { 3387d256175SHeiko Carstens if (!user_mode(regs)) 339aa33c8cbSMartin Schwidefsky do_no_context(regs); 34099583181SHeiko Carstens else 34150d7280dSMartin Schwidefsky pagefault_out_of_memory(); 34233692f27SLinus Torvalds } else if (fault & VM_FAULT_SIGSEGV) { 34333692f27SLinus Torvalds /* Kernel mode? Handle exceptions or die */ 34433692f27SLinus Torvalds if (!user_mode(regs)) 34533692f27SLinus Torvalds do_no_context(regs); 34633692f27SLinus Torvalds else 34733692f27SLinus Torvalds do_sigsegv(regs, SEGV_MAPERR); 34899583181SHeiko Carstens } else if (fault & VM_FAULT_SIGBUS) { 34950d7280dSMartin Schwidefsky /* Kernel mode? Handle exceptions or die */ 3507d256175SHeiko Carstens if (!user_mode(regs)) 351aa33c8cbSMartin Schwidefsky do_no_context(regs); 35236bf9680SMartin Schwidefsky else 353aa33c8cbSMartin Schwidefsky do_sigbus(regs); 35450d7280dSMartin Schwidefsky } else 35550d7280dSMartin Schwidefsky BUG(); 35650d7280dSMartin Schwidefsky break; 35750d7280dSMartin Schwidefsky } 35850d7280dSMartin Schwidefsky } 35950d7280dSMartin Schwidefsky 3601da177e4SLinus Torvalds /* 3611da177e4SLinus Torvalds * This routine handles page faults. It determines the address, 3621da177e4SLinus Torvalds * and the problem, and then passes it off to one of the appropriate 3631da177e4SLinus Torvalds * routines. 3641da177e4SLinus Torvalds * 36550d7280dSMartin Schwidefsky * interruption code (int_code): 3661da177e4SLinus Torvalds * 04 Protection -> Write-Protection (suprression) 3671da177e4SLinus Torvalds * 10 Segment translation -> Not present (nullification) 3681da177e4SLinus Torvalds * 11 Page translation -> Not present (nullification) 3691da177e4SLinus Torvalds * 3b Region third trans. -> Not present (nullification) 3701da177e4SLinus Torvalds */ 371aa33c8cbSMartin Schwidefsky static inline int do_exception(struct pt_regs *regs, int access) 3721da177e4SLinus Torvalds { 37324eb3a82SDominik Dingel #ifdef CONFIG_PGSTE 37424eb3a82SDominik Dingel struct gmap *gmap; 37524eb3a82SDominik Dingel #endif 3761da177e4SLinus Torvalds struct task_struct *tsk; 3771da177e4SLinus Torvalds struct mm_struct *mm; 3781da177e4SLinus Torvalds struct vm_area_struct *vma; 379aa33c8cbSMartin Schwidefsky unsigned long trans_exc_code; 3801da177e4SLinus Torvalds unsigned long address; 38133ce6140SHeiko Carstens unsigned int flags; 38233ce6140SHeiko Carstens int fault; 38310c1031fSMartin Schwidefsky 38439efd4ecSMartin Schwidefsky tsk = current; 38539efd4ecSMartin Schwidefsky /* 38639efd4ecSMartin Schwidefsky * The instruction that caused the program check has 38739efd4ecSMartin Schwidefsky * been nullified. Don't signal single step via SIGTRAP. 38839efd4ecSMartin Schwidefsky */ 389d3a73acbSMartin Schwidefsky clear_pt_regs_flag(regs, PIF_PER_TRAP); 39039efd4ecSMartin Schwidefsky 3917ecb344aSMartin Schwidefsky if (notify_page_fault(regs)) 39250d7280dSMartin Schwidefsky return 0; 3931da177e4SLinus Torvalds 3941da177e4SLinus Torvalds mm = tsk->mm; 395aa33c8cbSMartin Schwidefsky trans_exc_code = regs->int_parm_long; 3961da177e4SLinus Torvalds 3971da177e4SLinus Torvalds /* 3981da177e4SLinus Torvalds * Verify that the fault happened in user space, that 3991da177e4SLinus Torvalds * we are not in an interrupt and that there is a 4001da177e4SLinus Torvalds * user context. 4011da177e4SLinus Torvalds */ 40250d7280dSMartin Schwidefsky fault = VM_FAULT_BADCONTEXT; 40370ffdb93SDavid Hildenbrand if (unlikely(!user_space_fault(regs) || faulthandler_disabled() || !mm)) 40450d7280dSMartin Schwidefsky goto out; 4051da177e4SLinus Torvalds 40661365e13SMartin Schwidefsky address = trans_exc_code & __FAIL_ADDR_MASK; 407a8b0ca17SPeter Zijlstra perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); 408f2c76e3bSHeiko Carstens flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; 409759496baSJohannes Weiner if (user_mode(regs)) 410759496baSJohannes Weiner flags |= FAULT_FLAG_USER; 41133ce6140SHeiko Carstens if (access == VM_WRITE || (trans_exc_code & store_indication) == 0x400) 41233ce6140SHeiko Carstens flags |= FAULT_FLAG_WRITE; 4131da177e4SLinus Torvalds down_read(&mm->mmap_sem); 4141da177e4SLinus Torvalds 415e5992f2eSMartin Schwidefsky #ifdef CONFIG_PGSTE 416527e30b4SMartin Schwidefsky gmap = (current->flags & PF_VCPU) ? 417527e30b4SMartin Schwidefsky (struct gmap *) S390_lowcore.gmap : NULL; 41824eb3a82SDominik Dingel if (gmap) { 419527e30b4SMartin Schwidefsky current->thread.gmap_addr = address; 420527e30b4SMartin Schwidefsky address = __gmap_translate(gmap, address); 421e5992f2eSMartin Schwidefsky if (address == -EFAULT) { 422e5992f2eSMartin Schwidefsky fault = VM_FAULT_BADMAP; 423e5992f2eSMartin Schwidefsky goto out_up; 424e5992f2eSMartin Schwidefsky } 42524eb3a82SDominik Dingel if (gmap->pfault_enabled) 42624eb3a82SDominik Dingel flags |= FAULT_FLAG_RETRY_NOWAIT; 427e5992f2eSMartin Schwidefsky } 428e5992f2eSMartin Schwidefsky #endif 429e5992f2eSMartin Schwidefsky 430e5992f2eSMartin Schwidefsky retry: 43150d7280dSMartin Schwidefsky fault = VM_FAULT_BADMAP; 4321da177e4SLinus Torvalds vma = find_vma(mm, address); 4331da177e4SLinus Torvalds if (!vma) 43450d7280dSMartin Schwidefsky goto out_up; 435c1821c2eSGerald Schaefer 43650d7280dSMartin Schwidefsky if (unlikely(vma->vm_start > address)) { 4371da177e4SLinus Torvalds if (!(vma->vm_flags & VM_GROWSDOWN)) 43850d7280dSMartin Schwidefsky goto out_up; 4391da177e4SLinus Torvalds if (expand_stack(vma, address)) 44050d7280dSMartin Schwidefsky goto out_up; 44150d7280dSMartin Schwidefsky } 44250d7280dSMartin Schwidefsky 4431da177e4SLinus Torvalds /* 4441da177e4SLinus Torvalds * Ok, we have a good vm_area for this memory access, so 4451da177e4SLinus Torvalds * we can handle it.. 4461da177e4SLinus Torvalds */ 44750d7280dSMartin Schwidefsky fault = VM_FAULT_BADACCESS; 4481ab947deSMartin Schwidefsky if (unlikely(!(vma->vm_flags & access))) 44950d7280dSMartin Schwidefsky goto out_up; 4501da177e4SLinus Torvalds 45153492b1dSGerald Schaefer if (is_vm_hugetlb_page(vma)) 45253492b1dSGerald Schaefer address &= HPAGE_MASK; 4531da177e4SLinus Torvalds /* 4541da177e4SLinus Torvalds * If for any reason at all we couldn't handle the fault, 4551da177e4SLinus Torvalds * make sure we exit gracefully rather than endlessly redo 4561da177e4SLinus Torvalds * the fault. 4571da177e4SLinus Torvalds */ 45833ce6140SHeiko Carstens fault = handle_mm_fault(mm, vma, address, flags); 459f2c76e3bSHeiko Carstens /* No reason to continue if interrupted by SIGKILL. */ 460f2c76e3bSHeiko Carstens if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) { 461f2c76e3bSHeiko Carstens fault = VM_FAULT_SIGNAL; 462f2c76e3bSHeiko Carstens goto out; 463f2c76e3bSHeiko Carstens } 46450d7280dSMartin Schwidefsky if (unlikely(fault & VM_FAULT_ERROR)) 46550d7280dSMartin Schwidefsky goto out_up; 46650d7280dSMartin Schwidefsky 46733ce6140SHeiko Carstens /* 46833ce6140SHeiko Carstens * Major/minor page fault accounting is only done on the 46933ce6140SHeiko Carstens * initial attempt. If we go through a retry, it is extremely 47033ce6140SHeiko Carstens * likely that the page will be found in page cache at that point. 47133ce6140SHeiko Carstens */ 47233ce6140SHeiko Carstens if (flags & FAULT_FLAG_ALLOW_RETRY) { 473bde69af2SHeiko Carstens if (fault & VM_FAULT_MAJOR) { 47483c54070SNick Piggin tsk->maj_flt++; 475a8b0ca17SPeter Zijlstra perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 476bde69af2SHeiko Carstens regs, address); 477bde69af2SHeiko Carstens } else { 47883c54070SNick Piggin tsk->min_flt++; 479a8b0ca17SPeter Zijlstra perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 480bde69af2SHeiko Carstens regs, address); 481bde69af2SHeiko Carstens } 48233ce6140SHeiko Carstens if (fault & VM_FAULT_RETRY) { 48324eb3a82SDominik Dingel #ifdef CONFIG_PGSTE 48424eb3a82SDominik Dingel if (gmap && (flags & FAULT_FLAG_RETRY_NOWAIT)) { 48524eb3a82SDominik Dingel /* FAULT_FLAG_RETRY_NOWAIT has been set, 48624eb3a82SDominik Dingel * mmap_sem has not been released */ 48724eb3a82SDominik Dingel current->thread.gmap_pfault = 1; 48824eb3a82SDominik Dingel fault = VM_FAULT_PFAULT; 48924eb3a82SDominik Dingel goto out_up; 49024eb3a82SDominik Dingel } 49124eb3a82SDominik Dingel #endif 49233ce6140SHeiko Carstens /* Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk 49333ce6140SHeiko Carstens * of starvation. */ 49424eb3a82SDominik Dingel flags &= ~(FAULT_FLAG_ALLOW_RETRY | 49524eb3a82SDominik Dingel FAULT_FLAG_RETRY_NOWAIT); 49645cac65bSShaohua Li flags |= FAULT_FLAG_TRIED; 497e5992f2eSMartin Schwidefsky down_read(&mm->mmap_sem); 49833ce6140SHeiko Carstens goto retry; 49933ce6140SHeiko Carstens } 50033ce6140SHeiko Carstens } 501527e30b4SMartin Schwidefsky #ifdef CONFIG_PGSTE 502527e30b4SMartin Schwidefsky if (gmap) { 503527e30b4SMartin Schwidefsky address = __gmap_link(gmap, current->thread.gmap_addr, 504527e30b4SMartin Schwidefsky address); 505527e30b4SMartin Schwidefsky if (address == -EFAULT) { 506527e30b4SMartin Schwidefsky fault = VM_FAULT_BADMAP; 507527e30b4SMartin Schwidefsky goto out_up; 508527e30b4SMartin Schwidefsky } 509527e30b4SMartin Schwidefsky if (address == -ENOMEM) { 510527e30b4SMartin Schwidefsky fault = VM_FAULT_OOM; 511527e30b4SMartin Schwidefsky goto out_up; 512527e30b4SMartin Schwidefsky } 513527e30b4SMartin Schwidefsky } 514527e30b4SMartin Schwidefsky #endif 51550d7280dSMartin Schwidefsky fault = 0; 51650d7280dSMartin Schwidefsky out_up: 5171da177e4SLinus Torvalds up_read(&mm->mmap_sem); 51850d7280dSMartin Schwidefsky out: 51950d7280dSMartin Schwidefsky return fault; 5201da177e4SLinus Torvalds } 5211da177e4SLinus Torvalds 5227a5388deSHeiko Carstens void do_protection_exception(struct pt_regs *regs) 5231da177e4SLinus Torvalds { 524aa33c8cbSMartin Schwidefsky unsigned long trans_exc_code; 52550d7280dSMartin Schwidefsky int fault; 52661365e13SMartin Schwidefsky 527aa33c8cbSMartin Schwidefsky trans_exc_code = regs->int_parm_long; 528f752ac4dSMartin Schwidefsky /* 529f752ac4dSMartin Schwidefsky * Protection exceptions are suppressing, decrement psw address. 530f752ac4dSMartin Schwidefsky * The exception to this rule are aborted transactions, for these 531f752ac4dSMartin Schwidefsky * the PSW already points to the correct location. 532f752ac4dSMartin Schwidefsky */ 533f752ac4dSMartin Schwidefsky if (!(regs->int_code & 0x200)) 534aa33c8cbSMartin Schwidefsky regs->psw.addr = __rewind_psw(regs->psw, regs->int_code >> 16); 53510c1031fSMartin Schwidefsky /* 53610c1031fSMartin Schwidefsky * Check for low-address protection. This needs to be treated 53710c1031fSMartin Schwidefsky * as a special case because the translation exception code 53810c1031fSMartin Schwidefsky * field is not guaranteed to contain valid data in this case. 53910c1031fSMartin Schwidefsky */ 54061365e13SMartin Schwidefsky if (unlikely(!(trans_exc_code & 4))) { 541aa33c8cbSMartin Schwidefsky do_low_address(regs); 54210c1031fSMartin Schwidefsky return; 54310c1031fSMartin Schwidefsky } 544aa33c8cbSMartin Schwidefsky fault = do_exception(regs, VM_WRITE); 54550d7280dSMartin Schwidefsky if (unlikely(fault)) 546aa33c8cbSMartin Schwidefsky do_fault_error(regs, fault); 5471da177e4SLinus Torvalds } 5487a5388deSHeiko Carstens NOKPROBE_SYMBOL(do_protection_exception); 5491da177e4SLinus Torvalds 5507a5388deSHeiko Carstens void do_dat_exception(struct pt_regs *regs) 5511da177e4SLinus Torvalds { 5521ab947deSMartin Schwidefsky int access, fault; 55350d7280dSMartin Schwidefsky 5541ab947deSMartin Schwidefsky access = VM_READ | VM_EXEC | VM_WRITE; 555aa33c8cbSMartin Schwidefsky fault = do_exception(regs, access); 55650d7280dSMartin Schwidefsky if (unlikely(fault)) 557aa33c8cbSMartin Schwidefsky do_fault_error(regs, fault); 5581da177e4SLinus Torvalds } 5597a5388deSHeiko Carstens NOKPROBE_SYMBOL(do_dat_exception); 5601da177e4SLinus Torvalds 5611da177e4SLinus Torvalds #ifdef CONFIG_PFAULT 5621da177e4SLinus Torvalds /* 5631da177e4SLinus Torvalds * 'pfault' pseudo page faults routines. 5641da177e4SLinus Torvalds */ 565fb0a9d7eSHeiko Carstens static int pfault_disable; 5661da177e4SLinus Torvalds 5671da177e4SLinus Torvalds static int __init nopfault(char *str) 5681da177e4SLinus Torvalds { 5691da177e4SLinus Torvalds pfault_disable = 1; 5701da177e4SLinus Torvalds return 1; 5711da177e4SLinus Torvalds } 5721da177e4SLinus Torvalds 5731da177e4SLinus Torvalds __setup("nopfault", nopfault); 5741da177e4SLinus Torvalds 5757dd8fe1fSHeiko Carstens struct pfault_refbk { 5767dd8fe1fSHeiko Carstens u16 refdiagc; 5777dd8fe1fSHeiko Carstens u16 reffcode; 5787dd8fe1fSHeiko Carstens u16 refdwlen; 5797dd8fe1fSHeiko Carstens u16 refversn; 5807dd8fe1fSHeiko Carstens u64 refgaddr; 5817dd8fe1fSHeiko Carstens u64 refselmk; 5827dd8fe1fSHeiko Carstens u64 refcmpmk; 5837dd8fe1fSHeiko Carstens u64 reserved; 5847dd8fe1fSHeiko Carstens } __attribute__ ((packed, aligned(8))); 5851da177e4SLinus Torvalds 5861da177e4SLinus Torvalds int pfault_init(void) 5871da177e4SLinus Torvalds { 5887dd8fe1fSHeiko Carstens struct pfault_refbk refbk = { 5897dd8fe1fSHeiko Carstens .refdiagc = 0x258, 5907dd8fe1fSHeiko Carstens .reffcode = 0, 5917dd8fe1fSHeiko Carstens .refdwlen = 5, 5927dd8fe1fSHeiko Carstens .refversn = 2, 593e22cf8caSChristian Borntraeger .refgaddr = __LC_LPP, 5947dd8fe1fSHeiko Carstens .refselmk = 1ULL << 48, 5957dd8fe1fSHeiko Carstens .refcmpmk = 1ULL << 48, 5967dd8fe1fSHeiko Carstens .reserved = __PF_RES_FIELD }; 5971da177e4SLinus Torvalds int rc; 5981da177e4SLinus Torvalds 599f32269a0SCarsten Otte if (pfault_disable) 6001da177e4SLinus Torvalds return -1; 6011ec2772eSMartin Schwidefsky diag_stat_inc(DIAG_STAT_X258); 60294c12cc7SMartin Schwidefsky asm volatile( 6031da177e4SLinus Torvalds " diag %1,%0,0x258\n" 6041da177e4SLinus Torvalds "0: j 2f\n" 6051da177e4SLinus Torvalds "1: la %0,8\n" 6061da177e4SLinus Torvalds "2:\n" 60794c12cc7SMartin Schwidefsky EX_TABLE(0b,1b) 608d4b68996SMartin Schwidefsky : "=d" (rc) : "a" (&refbk), "m" (refbk) : "cc"); 6091da177e4SLinus Torvalds return rc; 6101da177e4SLinus Torvalds } 6111da177e4SLinus Torvalds 6121da177e4SLinus Torvalds void pfault_fini(void) 6131da177e4SLinus Torvalds { 6147dd8fe1fSHeiko Carstens struct pfault_refbk refbk = { 6157dd8fe1fSHeiko Carstens .refdiagc = 0x258, 6167dd8fe1fSHeiko Carstens .reffcode = 1, 6177dd8fe1fSHeiko Carstens .refdwlen = 5, 6187dd8fe1fSHeiko Carstens .refversn = 2, 6197dd8fe1fSHeiko Carstens }; 6201da177e4SLinus Torvalds 621f32269a0SCarsten Otte if (pfault_disable) 6221da177e4SLinus Torvalds return; 6231ec2772eSMartin Schwidefsky diag_stat_inc(DIAG_STAT_X258); 62494c12cc7SMartin Schwidefsky asm volatile( 6251da177e4SLinus Torvalds " diag %0,0,0x258\n" 6261da177e4SLinus Torvalds "0:\n" 62794c12cc7SMartin Schwidefsky EX_TABLE(0b,0b) 628d4b68996SMartin Schwidefsky : : "a" (&refbk), "m" (refbk) : "cc"); 6291da177e4SLinus Torvalds } 6301da177e4SLinus Torvalds 631f2db2e6cSHeiko Carstens static DEFINE_SPINLOCK(pfault_lock); 632f2db2e6cSHeiko Carstens static LIST_HEAD(pfault_list); 633f2db2e6cSHeiko Carstens 634fde15c3aSHeiko Carstens static void pfault_interrupt(struct ext_code ext_code, 635f6649a7eSMartin Schwidefsky unsigned int param32, unsigned long param64) 6361da177e4SLinus Torvalds { 6371da177e4SLinus Torvalds struct task_struct *tsk; 6381da177e4SLinus Torvalds __u16 subcode; 639f2db2e6cSHeiko Carstens pid_t pid; 6401da177e4SLinus Torvalds 6411da177e4SLinus Torvalds /* 6421da177e4SLinus Torvalds * Get the external interruption subcode & pfault 6431da177e4SLinus Torvalds * initial/completion signal bit. VM stores this 6441da177e4SLinus Torvalds * in the 'cpu address' field associated with the 6451da177e4SLinus Torvalds * external interrupt. 6461da177e4SLinus Torvalds */ 647fde15c3aSHeiko Carstens subcode = ext_code.subcode; 6481da177e4SLinus Torvalds if ((subcode & 0xff00) != __SUBCODE_MASK) 6491da177e4SLinus Torvalds return; 650420f42ecSHeiko Carstens inc_irq_stat(IRQEXT_PFL); 651f2db2e6cSHeiko Carstens /* Get the token (= pid of the affected task). */ 652e22cf8caSChristian Borntraeger pid = param64 & LPP_PFAULT_PID_MASK; 653f2db2e6cSHeiko Carstens rcu_read_lock(); 654f2db2e6cSHeiko Carstens tsk = find_task_by_pid_ns(pid, &init_pid_ns); 655f2db2e6cSHeiko Carstens if (tsk) 656f2db2e6cSHeiko Carstens get_task_struct(tsk); 657f2db2e6cSHeiko Carstens rcu_read_unlock(); 658f2db2e6cSHeiko Carstens if (!tsk) 659f2db2e6cSHeiko Carstens return; 660f2db2e6cSHeiko Carstens spin_lock(&pfault_lock); 6611da177e4SLinus Torvalds if (subcode & 0x0080) { 6621da177e4SLinus Torvalds /* signal bit is set -> a page has been swapped in by VM */ 663f2db2e6cSHeiko Carstens if (tsk->thread.pfault_wait == 1) { 6641da177e4SLinus Torvalds /* Initial interrupt was faster than the completion 6651da177e4SLinus Torvalds * interrupt. pfault_wait is valid. Set pfault_wait 6661da177e4SLinus Torvalds * back to zero and wake up the process. This can 6671da177e4SLinus Torvalds * safely be done because the task is still sleeping 668b6d09449SMartin Schwidefsky * and can't produce new pfaults. */ 6691da177e4SLinus Torvalds tsk->thread.pfault_wait = 0; 670f2db2e6cSHeiko Carstens list_del(&tsk->thread.list); 6711da177e4SLinus Torvalds wake_up_process(tsk); 672d5e50a51SHeiko Carstens put_task_struct(tsk); 673f2db2e6cSHeiko Carstens } else { 674f2db2e6cSHeiko Carstens /* Completion interrupt was faster than initial 675f2db2e6cSHeiko Carstens * interrupt. Set pfault_wait to -1 so the initial 676fa2fb2f4SHeiko Carstens * interrupt doesn't put the task to sleep. 677fa2fb2f4SHeiko Carstens * If the task is not running, ignore the completion 678fa2fb2f4SHeiko Carstens * interrupt since it must be a leftover of a PFAULT 679fa2fb2f4SHeiko Carstens * CANCEL operation which didn't remove all pending 680fa2fb2f4SHeiko Carstens * completion interrupts. */ 681fa2fb2f4SHeiko Carstens if (tsk->state == TASK_RUNNING) 682f2db2e6cSHeiko Carstens tsk->thread.pfault_wait = -1; 6831da177e4SLinus Torvalds } 6841da177e4SLinus Torvalds } else { 6851da177e4SLinus Torvalds /* signal bit not set -> a real page is missing. */ 686d49f47f8SHeiko Carstens if (WARN_ON_ONCE(tsk != current)) 687d49f47f8SHeiko Carstens goto out; 688d5e50a51SHeiko Carstens if (tsk->thread.pfault_wait == 1) { 689d5e50a51SHeiko Carstens /* Already on the list with a reference: put to sleep */ 6900a16ba78SHeiko Carstens __set_task_state(tsk, TASK_UNINTERRUPTIBLE); 691d5e50a51SHeiko Carstens set_tsk_need_resched(tsk); 692d5e50a51SHeiko Carstens } else if (tsk->thread.pfault_wait == -1) { 6931da177e4SLinus Torvalds /* Completion interrupt was faster than the initial 694f2db2e6cSHeiko Carstens * interrupt (pfault_wait == -1). Set pfault_wait 695f2db2e6cSHeiko Carstens * back to zero and exit. */ 6961da177e4SLinus Torvalds tsk->thread.pfault_wait = 0; 697f2db2e6cSHeiko Carstens } else { 698f2db2e6cSHeiko Carstens /* Initial interrupt arrived before completion 699d5e50a51SHeiko Carstens * interrupt. Let the task sleep. 700d5e50a51SHeiko Carstens * An extra task reference is needed since a different 701d5e50a51SHeiko Carstens * cpu may set the task state to TASK_RUNNING again 702d5e50a51SHeiko Carstens * before the scheduler is reached. */ 703d5e50a51SHeiko Carstens get_task_struct(tsk); 704f2db2e6cSHeiko Carstens tsk->thread.pfault_wait = 1; 705f2db2e6cSHeiko Carstens list_add(&tsk->thread.list, &pfault_list); 7060a16ba78SHeiko Carstens __set_task_state(tsk, TASK_UNINTERRUPTIBLE); 7071da177e4SLinus Torvalds set_tsk_need_resched(tsk); 7081da177e4SLinus Torvalds } 7091da177e4SLinus Torvalds } 710d49f47f8SHeiko Carstens out: 711f2db2e6cSHeiko Carstens spin_unlock(&pfault_lock); 71254c27791SHeiko Carstens put_task_struct(tsk); 713f2db2e6cSHeiko Carstens } 714f2db2e6cSHeiko Carstens 715e2741f17SPaul Gortmaker static int pfault_cpu_notify(struct notifier_block *self, unsigned long action, 716e2741f17SPaul Gortmaker void *hcpu) 717f2db2e6cSHeiko Carstens { 718f2db2e6cSHeiko Carstens struct thread_struct *thread, *next; 719f2db2e6cSHeiko Carstens struct task_struct *tsk; 720f2db2e6cSHeiko Carstens 7211c725922SHeiko Carstens switch (action & ~CPU_TASKS_FROZEN) { 722f2db2e6cSHeiko Carstens case CPU_DEAD: 723f2db2e6cSHeiko Carstens spin_lock_irq(&pfault_lock); 724f2db2e6cSHeiko Carstens list_for_each_entry_safe(thread, next, &pfault_list, list) { 725f2db2e6cSHeiko Carstens thread->pfault_wait = 0; 726f2db2e6cSHeiko Carstens list_del(&thread->list); 727f2db2e6cSHeiko Carstens tsk = container_of(thread, struct task_struct, thread); 728f2db2e6cSHeiko Carstens wake_up_process(tsk); 729d5e50a51SHeiko Carstens put_task_struct(tsk); 730f2db2e6cSHeiko Carstens } 731f2db2e6cSHeiko Carstens spin_unlock_irq(&pfault_lock); 732f2db2e6cSHeiko Carstens break; 733f2db2e6cSHeiko Carstens default: 734f2db2e6cSHeiko Carstens break; 735f2db2e6cSHeiko Carstens } 736f2db2e6cSHeiko Carstens return NOTIFY_OK; 737f2db2e6cSHeiko Carstens } 7381da177e4SLinus Torvalds 739fb0a9d7eSHeiko Carstens static int __init pfault_irq_init(void) 74029b08d2bSHeiko Carstens { 741fb0a9d7eSHeiko Carstens int rc; 74229b08d2bSHeiko Carstens 7431dad093bSThomas Huth rc = register_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt); 7447dd8fe1fSHeiko Carstens if (rc) 7457dd8fe1fSHeiko Carstens goto out_extint; 7467dd8fe1fSHeiko Carstens rc = pfault_init() == 0 ? 0 : -EOPNOTSUPP; 7477dd8fe1fSHeiko Carstens if (rc) 7487dd8fe1fSHeiko Carstens goto out_pfault; 74982003c3eSHeiko Carstens irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL); 7507dd8fe1fSHeiko Carstens hotcpu_notifier(pfault_cpu_notify, 0); 7517dd8fe1fSHeiko Carstens return 0; 7527dd8fe1fSHeiko Carstens 7537dd8fe1fSHeiko Carstens out_pfault: 7541dad093bSThomas Huth unregister_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt); 7557dd8fe1fSHeiko Carstens out_extint: 756fb0a9d7eSHeiko Carstens pfault_disable = 1; 757fb0a9d7eSHeiko Carstens return rc; 758fb0a9d7eSHeiko Carstens } 759fb0a9d7eSHeiko Carstens early_initcall(pfault_irq_init); 760fb0a9d7eSHeiko Carstens 7617dd8fe1fSHeiko Carstens #endif /* CONFIG_PFAULT */ 762