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Diffstat (limited to 'arch/parisc/mm/fault.c')
-rw-r--r--arch/parisc/mm/fault.c201
1 files changed, 141 insertions, 60 deletions
diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index b2e3e9a8cec..3ca9c1131cf 100644
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -1,5 +1,4 @@
-/* $Id: fault.c,v 1.5 2000/01/26 16:20:29 jsm Exp $
- *
+/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
@@ -20,10 +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)
@@ -35,6 +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
@@ -139,19 +136,93 @@ parisc_acctyp(unsigned long code, unsigned int inst)
}
#endif
+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 = this_cpu_ptr(&exception_data);
+ d->fault_ip = regs->iaoq[0];
+ d->fault_space = regs->isr;
+ d->fault_addr = regs->ior;
+
+ regs->iaoq[0] = ((fix->fixup) & ~3);
+ /*
+ * NOTE: In some cases the faulting instruction
+ * may be in the delay slot of a branch. We
+ * don't want to take the branch, so we don't
+ * increment iaoq[1], instead we set it to be
+ * iaoq[0]+4, and clear the B bit in the PSW
+ */
+ regs->iaoq[1] = regs->iaoq[0] + 4;
+ regs->gr[0] &= ~PSW_B; /* IPSW in gr[0] */
+
+ return 1;
+ }
+
+ 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;
- const struct exception_table_entry *fix;
+ struct task_struct *tsk;
+ struct mm_struct *mm;
unsigned long acc_type;
int fault;
+ unsigned int flags;
- if (in_atomic() || !mm)
+ if (in_atomic())
goto no_context;
+ 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)
@@ -163,8 +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;
@@ -174,7 +243,11 @@ good_area:
* fault.
*/
- fault = handle_mm_fault(mm, vma, address, (acc_type & VM_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
@@ -187,10 +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;
@@ -208,61 +294,56 @@ 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;
}
no_context:
- if (!user_mode(regs)) {
- fix = search_exception_tables(regs->iaoq[0]);
-
- if (fix) {
- struct exception_data *d;
-
- d = &__get_cpu_var(exception_data);
- d->fault_ip = regs->iaoq[0];
- d->fault_space = regs->isr;
- d->fault_addr = regs->ior;
-
- regs->iaoq[0] = ((fix->fixup) & ~3);
-
- /*
- * NOTE: In some cases the faulting instruction
- * may be in the delay slot of a branch. We
- * don't want to take the branch, so we don't
- * increment iaoq[1], instead we set it to be
- * iaoq[0]+4, and clear the B bit in the PSW
- */
-
- regs->iaoq[1] = regs->iaoq[0] + 4;
- regs->gr[0] &= ~PSW_B; /* IPSW in gr[0] */
-
- return;
- }
+ if (!user_mode(regs) && fixup_exception(regs)) {
+ return;
}
parisc_terminate("Bad Address (null pointer deref?)", regs, code, address);
out_of_memory:
up_read(&mm->mmap_sem);
- printk(KERN_CRIT "VM: killing process %s\n", current->comm);
- if (user_mode(regs))
- do_group_exit(SIGKILL);
- goto no_context;
+ if (!user_mode(regs))
+ goto no_context;
+ pagefault_out_of_memory();
}
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