* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
-#include <linux/config.h>
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/ptrace.h>
/* We must not map this if we have highmem enabled */
pte = pte_offset_map(pmd, addr);
printk(", *pte=%08lx", pte_val(*pte));
-#ifdef CONFIG_CPU_32
printk(", *ppte=%08lx", pte_val(pte[-PTRS_PER_PTE]));
-#endif
pte_unmap(pte);
#endif
} while(0);
*/
static void
__do_user_fault(struct task_struct *tsk, unsigned long addr,
- unsigned int fsr, int code, struct pt_regs *regs)
+ unsigned int fsr, unsigned int sig, int code,
+ struct pt_regs *regs)
{
struct siginfo si;
#ifdef CONFIG_DEBUG_USER
if (user_debug & UDBG_SEGV) {
- printk(KERN_DEBUG "%s: unhandled page fault at 0x%08lx, code 0x%03x\n",
- tsk->comm, addr, fsr);
+ printk(KERN_DEBUG "%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n",
+ tsk->comm, sig, addr, fsr);
show_pte(tsk->mm, addr);
show_regs(regs);
}
tsk->thread.address = addr;
tsk->thread.error_code = fsr;
tsk->thread.trap_no = 14;
- si.si_signo = SIGSEGV;
+ si.si_signo = sig;
si.si_errno = 0;
si.si_code = code;
- si.si_addr = (void *)addr;
- force_sig_info(SIGSEGV, &si, tsk);
+ si.si_addr = (void __user *)addr;
+ force_sig_info(sig, &si, tsk);
}
-void
-do_bad_area(struct task_struct *tsk, struct mm_struct *mm, unsigned long addr,
- unsigned int fsr, struct pt_regs *regs)
+void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
+ struct task_struct *tsk = current;
+ struct mm_struct *mm = tsk->active_mm;
+
/*
* If we are in kernel mode at this point, we
* have no context to handle this fault with.
*/
if (user_mode(regs))
- __do_user_fault(tsk, addr, fsr, SEGV_MAPERR, regs);
+ __do_user_fault(tsk, addr, fsr, SIGSEGV, SEGV_MAPERR, regs);
else
__do_kernel_fault(mm, addr, fsr, regs);
}
if (fsr & (1 << 11)) /* write? */
mask = VM_WRITE;
else
- mask = VM_READ|VM_EXEC;
+ mask = VM_READ|VM_EXEC|VM_WRITE;
fault = VM_FAULT_BADACCESS;
if (!(vma->vm_flags & mask))
return fault;
}
- if (tsk->pid != 1)
+ if (!is_init(tsk))
goto out;
/*
- * If we are out of memory for pid1,
- * sleep for a while and retry
+ * If we are out of memory for pid1, sleep for a while and retry
*/
+ up_read(&mm->mmap_sem);
yield();
+ down_read(&mm->mmap_sem);
goto survive;
check_stack:
{
struct task_struct *tsk;
struct mm_struct *mm;
- int fault;
+ int fault, sig, code;
tsk = current;
mm = tsk->mm;
* If we're in an interrupt or have no user
* context, we must not take the fault..
*/
- if (in_interrupt() || !mm)
+ if (in_atomic() || !mm)
goto no_context;
- down_read(&mm->mmap_sem);
+ /*
+ * As per x86, we may deadlock here. However, since the kernel only
+ * validly references user space from well defined areas of the code,
+ * we can bug out early if this is from code which shouldn't.
+ */
+ if (!down_read_trylock(&mm->mmap_sem)) {
+ if (!user_mode(regs) && !search_exception_tables(regs->ARM_pc))
+ goto no_context;
+ down_read(&mm->mmap_sem);
+ }
+
fault = __do_page_fault(mm, addr, fsr, tsk);
up_read(&mm->mmap_sem);
/*
- * Handle the "normal" case first
+ * Handle the "normal" case first - VM_FAULT_MAJOR / VM_FAULT_MINOR
*/
- if (fault > 0)
+ if (fault >= VM_FAULT_MINOR)
return 0;
- /*
- * We had some memory, but were unable to
- * successfully fix up this page fault.
- */
- if (fault == 0)
- goto do_sigbus;
-
/*
* If we are in kernel mode at this point, we
* have no context to handle this fault with.
if (!user_mode(regs))
goto no_context;
- if (fault == VM_FAULT_OOM) {
+ switch (fault) {
+ case VM_FAULT_OOM:
/*
- * We ran out of memory, or some other thing happened to
- * us that made us unable to handle the page fault gracefully.
+ * We ran out of memory, or some other thing
+ * happened to us that made us unable to handle
+ * the page fault gracefully.
*/
- printk("VM: killing process %s\n", tsk->comm);
+ printk("VM: killing process %s(%d:#%u)\n",
+ tsk->comm, tsk->pid, tsk->xid);
do_exit(SIGKILL);
- } else
- __do_user_fault(tsk, addr, fsr, fault == VM_FAULT_BADACCESS ?
- SEGV_ACCERR : SEGV_MAPERR, regs);
- return 0;
+ return 0;
+ case VM_FAULT_SIGBUS:
+ /*
+ * We had some memory, but were unable to
+ * successfully fix up this page fault.
+ */
+ sig = SIGBUS;
+ code = BUS_ADRERR;
+ break;
-/*
- * We ran out of memory, or some other thing happened to us that made
- * us unable to handle the page fault gracefully.
- */
-do_sigbus:
- /*
- * Send a sigbus, regardless of whether we were in kernel
- * or user mode.
- */
- tsk->thread.address = addr;
- tsk->thread.error_code = fsr;
- tsk->thread.trap_no = 14;
- force_sig(SIGBUS, tsk);
-#ifdef CONFIG_DEBUG_USER
- if (user_debug & UDBG_BUS) {
- printk(KERN_DEBUG "%s: sigbus at 0x%08lx, pc=0x%08lx\n",
- current->comm, addr, instruction_pointer(regs));
+ default:
+ /*
+ * Something tried to access memory that
+ * isn't in our memory map..
+ */
+ sig = SIGSEGV;
+ code = fault == VM_FAULT_BADACCESS ?
+ SEGV_ACCERR : SEGV_MAPERR;
+ break;
}
-#endif
- /* Kernel mode? Handle exceptions or die */
- if (user_mode(regs))
- return 0;
+ __do_user_fault(tsk, addr, fsr, sig, code, regs);
+ return 0;
no_context:
__do_kernel_fault(mm, addr, fsr, regs);
do_translation_fault(unsigned long addr, unsigned int fsr,
struct pt_regs *regs)
{
- struct task_struct *tsk;
unsigned int index;
pgd_t *pgd, *pgd_k;
pmd_t *pmd, *pmd_k;
if (pmd_none(*pmd_k))
goto bad_area;
- set_pmd(pmd, *pmd_k);
+ copy_pmd(pmd, pmd_k);
return 0;
bad_area:
- tsk = current;
-
- do_bad_area(tsk, tsk->active_mm, addr, fsr, regs);
+ do_bad_area(addr, fsr, regs);
return 0;
}
static int
do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
- struct task_struct *tsk = current;
- do_bad_area(tsk, tsk->active_mm, addr, fsr, regs);
+ do_bad_area(addr, fsr, regs);
return 0;
}
static struct fsr_info {
int (*fn)(unsigned long addr, unsigned int fsr, struct pt_regs *regs);
int sig;
+ int code;
const char *name;
} fsr_info[] = {
/*
* The following are the standard ARMv3 and ARMv4 aborts. ARMv5
* defines these to be "precise" aborts.
*/
- { do_bad, SIGSEGV, "vector exception" },
- { do_bad, SIGILL, "alignment exception" },
- { do_bad, SIGKILL, "terminal exception" },
- { do_bad, SIGILL, "alignment exception" },
- { do_bad, SIGBUS, "external abort on linefetch" },
- { do_translation_fault, SIGSEGV, "section translation fault" },
- { do_bad, SIGBUS, "external abort on linefetch" },
- { do_page_fault, SIGSEGV, "page translation fault" },
- { do_bad, SIGBUS, "external abort on non-linefetch" },
- { do_bad, SIGSEGV, "section domain fault" },
- { do_bad, SIGBUS, "external abort on non-linefetch" },
- { do_bad, SIGSEGV, "page domain fault" },
- { do_bad, SIGBUS, "external abort on translation" },
- { do_sect_fault, SIGSEGV, "section permission fault" },
- { do_bad, SIGBUS, "external abort on translation" },
- { do_page_fault, SIGSEGV, "page permission fault" },
+ { do_bad, SIGSEGV, 0, "vector exception" },
+ { do_bad, SIGILL, BUS_ADRALN, "alignment exception" },
+ { do_bad, SIGKILL, 0, "terminal exception" },
+ { do_bad, SIGILL, BUS_ADRALN, "alignment exception" },
+ { do_bad, SIGBUS, 0, "external abort on linefetch" },
+ { do_translation_fault, SIGSEGV, SEGV_MAPERR, "section translation fault" },
+ { do_bad, SIGBUS, 0, "external abort on linefetch" },
+ { do_page_fault, SIGSEGV, SEGV_MAPERR, "page translation fault" },
+ { do_bad, SIGBUS, 0, "external abort on non-linefetch" },
+ { do_bad, SIGSEGV, SEGV_ACCERR, "section domain fault" },
+ { do_bad, SIGBUS, 0, "external abort on non-linefetch" },
+ { do_bad, SIGSEGV, SEGV_ACCERR, "page domain fault" },
+ { do_bad, SIGBUS, 0, "external abort on translation" },
+ { do_sect_fault, SIGSEGV, SEGV_ACCERR, "section permission fault" },
+ { do_bad, SIGBUS, 0, "external abort on translation" },
+ { do_page_fault, SIGSEGV, SEGV_ACCERR, "page permission fault" },
/*
* The following are "imprecise" aborts, which are signalled by bit
* 10 of the FSR, and may not be recoverable. These are only
* supported if the CPU abort handler supports bit 10.
*/
- { do_bad, SIGBUS, "unknown 16" },
- { do_bad, SIGBUS, "unknown 17" },
- { do_bad, SIGBUS, "unknown 18" },
- { do_bad, SIGBUS, "unknown 19" },
- { do_bad, SIGBUS, "lock abort" }, /* xscale */
- { do_bad, SIGBUS, "unknown 21" },
- { do_bad, SIGBUS, "imprecise external abort" }, /* xscale */
- { do_bad, SIGBUS, "unknown 23" },
- { do_bad, SIGBUS, "dcache parity error" }, /* xscale */
- { do_bad, SIGBUS, "unknown 25" },
- { do_bad, SIGBUS, "unknown 26" },
- { do_bad, SIGBUS, "unknown 27" },
- { do_bad, SIGBUS, "unknown 28" },
- { do_bad, SIGBUS, "unknown 29" },
- { do_bad, SIGBUS, "unknown 30" },
- { do_bad, SIGBUS, "unknown 31" }
+ { do_bad, SIGBUS, 0, "unknown 16" },
+ { do_bad, SIGBUS, 0, "unknown 17" },
+ { do_bad, SIGBUS, 0, "unknown 18" },
+ { do_bad, SIGBUS, 0, "unknown 19" },
+ { do_bad, SIGBUS, 0, "lock abort" }, /* xscale */
+ { do_bad, SIGBUS, 0, "unknown 21" },
+ { do_bad, SIGBUS, BUS_OBJERR, "imprecise external abort" }, /* xscale */
+ { do_bad, SIGBUS, 0, "unknown 23" },
+ { do_bad, SIGBUS, 0, "dcache parity error" }, /* xscale */
+ { do_bad, SIGBUS, 0, "unknown 25" },
+ { do_bad, SIGBUS, 0, "unknown 26" },
+ { do_bad, SIGBUS, 0, "unknown 27" },
+ { do_bad, SIGBUS, 0, "unknown 28" },
+ { do_bad, SIGBUS, 0, "unknown 29" },
+ { do_bad, SIGBUS, 0, "unknown 30" },
+ { do_bad, SIGBUS, 0, "unknown 31" }
};
void __init
do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
const struct fsr_info *inf = fsr_info + (fsr & 15) + ((fsr & (1 << 10)) >> 6);
+ struct siginfo info;
if (!inf->fn(addr, fsr, regs))
return;
printk(KERN_ALERT "Unhandled fault: %s (0x%03x) at 0x%08lx\n",
inf->name, fsr, addr);
- force_sig(inf->sig, current);
- show_pte(current->mm, addr);
- die_if_kernel("Oops", regs, 0);
+
+ info.si_signo = inf->sig;
+ info.si_errno = 0;
+ info.si_code = inf->code;
+ info.si_addr = (void __user *)addr;
+ notify_die("", regs, &info, fsr, 0);
}
asmlinkage void
git://git.onelab.eu / linux-2.6.git / blobdiff