diff options
Diffstat (limited to 'arch/parisc/mm/fault.c')
| -rw-r--r-- | arch/parisc/mm/fault.c | 135 |
1 files changed, 107 insertions, 28 deletions
diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c index 18162ce4261..3ca9c1131cf 100644 --- a/arch/parisc/mm/fault.c +++ b/arch/parisc/mm/fault.c @@ -19,10 +19,6 @@ #include <asm/uaccess.h> #include <asm/traps.h> -#define PRINT_USER_FAULTS /* (turn this on if you want user faults to be */ - /* dumped to the console via printk) */ - - /* Various important other fields */ #define bit22set(x) (x & 0x00000200) #define bits23_25set(x) (x & 0x000001c0) @@ -34,6 +30,8 @@ DEFINE_PER_CPU(struct exception_data, exception_data); +int show_unhandled_signals = 1; + /* * parisc_acctyp(unsigned int inst) -- * Given a PA-RISC memory access instruction, determine if the @@ -142,10 +140,16 @@ int fixup_exception(struct pt_regs *regs) { const struct exception_table_entry *fix; + /* If we only stored 32bit addresses in the exception table we can drop + * out if we faulted on a 64bit address. */ + if ((sizeof(regs->iaoq[0]) > sizeof(fix->insn)) + && (regs->iaoq[0] >> 32)) + return 0; + fix = search_exception_tables(regs->iaoq[0]); if (fix) { struct exception_data *d; - d = &__get_cpu_var(exception_data); + d = this_cpu_ptr(&exception_data); d->fault_ip = regs->iaoq[0]; d->fault_space = regs->isr; d->fault_addr = regs->ior; @@ -167,18 +171,58 @@ int fixup_exception(struct pt_regs *regs) return 0; } +/* + * Print out info about fatal segfaults, if the show_unhandled_signals + * sysctl is set: + */ +static inline void +show_signal_msg(struct pt_regs *regs, unsigned long code, + unsigned long address, struct task_struct *tsk, + struct vm_area_struct *vma) +{ + if (!unhandled_signal(tsk, SIGSEGV)) + return; + + if (!printk_ratelimit()) + return; + + pr_warn("\n"); + pr_warn("do_page_fault() command='%s' type=%lu address=0x%08lx", + tsk->comm, code, address); + print_vma_addr(KERN_CONT " in ", regs->iaoq[0]); + if (vma) + pr_warn(" vm_start = 0x%08lx, vm_end = 0x%08lx\n", + vma->vm_start, vma->vm_end); + + show_regs(regs); +} + void do_page_fault(struct pt_regs *regs, unsigned long code, unsigned long address) { struct vm_area_struct *vma, *prev_vma; - struct task_struct *tsk = current; - struct mm_struct *mm = tsk->mm; + struct task_struct *tsk; + struct mm_struct *mm; unsigned long acc_type; int fault; + unsigned int flags; + + if (in_atomic()) + goto no_context; - if (in_atomic() || !mm) + tsk = current; + mm = tsk->mm; + if (!mm) goto no_context; + flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; + if (user_mode(regs)) + flags |= FAULT_FLAG_USER; + + acc_type = parisc_acctyp(code, regs->iir); + if (acc_type & VM_WRITE) + flags |= FAULT_FLAG_WRITE; +retry: down_read(&mm->mmap_sem); vma = find_vma_prev(mm, address, &prev_vma); if (!vma || address < vma->vm_start) @@ -190,8 +234,6 @@ void do_page_fault(struct pt_regs *regs, unsigned long code, good_area: - acc_type = parisc_acctyp(code,regs->iir); - if ((vma->vm_flags & acc_type) != acc_type) goto bad_area; @@ -201,7 +243,11 @@ good_area: * fault. */ - fault = handle_mm_fault(mm, vma, address, (acc_type & VM_WRITE) ? FAULT_FLAG_WRITE : 0); + fault = handle_mm_fault(mm, vma, address, flags); + + if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) + return; + if (unlikely(fault & VM_FAULT_ERROR)) { /* * We hit a shared mapping outside of the file, or some @@ -214,10 +260,23 @@ good_area: goto bad_area; BUG(); } - if (fault & VM_FAULT_MAJOR) - current->maj_flt++; - else - current->min_flt++; + if (flags & FAULT_FLAG_ALLOW_RETRY) { + if (fault & VM_FAULT_MAJOR) + current->maj_flt++; + else + current->min_flt++; + if (fault & VM_FAULT_RETRY) { + flags &= ~FAULT_FLAG_ALLOW_RETRY; + + /* + * No need to up_read(&mm->mmap_sem) as we would + * have already released it in __lock_page_or_retry + * in mm/filemap.c. + */ + + goto retry; + } + } up_read(&mm->mmap_sem); return; @@ -235,22 +294,42 @@ bad_area: if (user_mode(regs)) { struct siginfo si; -#ifdef PRINT_USER_FAULTS - printk(KERN_DEBUG "\n"); - printk(KERN_DEBUG "do_page_fault() pid=%d command='%s' type=%lu address=0x%08lx\n", - task_pid_nr(tsk), tsk->comm, code, address); - if (vma) { - printk(KERN_DEBUG "vm_start = 0x%08lx, vm_end = 0x%08lx\n", - vma->vm_start, vma->vm_end); + show_signal_msg(regs, code, address, tsk, vma); + + switch (code) { + case 15: /* Data TLB miss fault/Data page fault */ + /* send SIGSEGV when outside of vma */ + if (!vma || + address < vma->vm_start || address > vma->vm_end) { + si.si_signo = SIGSEGV; + si.si_code = SEGV_MAPERR; + break; + } + + /* send SIGSEGV for wrong permissions */ + if ((vma->vm_flags & acc_type) != acc_type) { + si.si_signo = SIGSEGV; + si.si_code = SEGV_ACCERR; + break; + } + + /* probably address is outside of mapped file */ + /* fall through */ + case 17: /* NA data TLB miss / page fault */ + case 18: /* Unaligned access - PCXS only */ + si.si_signo = SIGBUS; + si.si_code = (code == 18) ? BUS_ADRALN : BUS_ADRERR; + break; + case 16: /* Non-access instruction TLB miss fault */ + case 26: /* PCXL: Data memory access rights trap */ + default: + si.si_signo = SIGSEGV; + si.si_code = (code == 26) ? SEGV_ACCERR : SEGV_MAPERR; + break; } - show_regs(regs); -#endif - /* FIXME: actually we need to get the signo and code correct */ - si.si_signo = SIGSEGV; si.si_errno = 0; - si.si_code = SEGV_MAPERR; si.si_addr = (void __user *) address; - force_sig_info(SIGSEGV, &si, current); + force_sig_info(si.si_signo, &si, current); return; } |