018b8d12bc
Fix the exception table handling so that modules exceptions are dealt with. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
76 lines
2.4 KiB
C
76 lines
2.4 KiB
C
/*
|
|
* linux/arch/frv/mm/extable.c
|
|
*/
|
|
|
|
#include <linux/config.h>
|
|
#include <linux/module.h>
|
|
#include <linux/spinlock.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
extern const struct exception_table_entry __attribute__((aligned(8))) __start___ex_table[];
|
|
extern const struct exception_table_entry __attribute__((aligned(8))) __stop___ex_table[];
|
|
extern const void __memset_end, __memset_user_error_lr, __memset_user_error_handler;
|
|
extern const void __memcpy_end, __memcpy_user_error_lr, __memcpy_user_error_handler;
|
|
extern spinlock_t modlist_lock;
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
*
|
|
*/
|
|
static inline unsigned long search_one_table(const struct exception_table_entry *first,
|
|
const struct exception_table_entry *last,
|
|
unsigned long value)
|
|
{
|
|
while (first <= last) {
|
|
const struct exception_table_entry __attribute__((aligned(8))) *mid;
|
|
long diff;
|
|
|
|
mid = (last - first) / 2 + first;
|
|
diff = mid->insn - value;
|
|
if (diff == 0)
|
|
return mid->fixup;
|
|
else if (diff < 0)
|
|
first = mid + 1;
|
|
else
|
|
last = mid - 1;
|
|
}
|
|
return 0;
|
|
} /* end search_one_table() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* see if there's a fixup handler available to deal with a kernel fault
|
|
*/
|
|
unsigned long search_exception_table(unsigned long pc)
|
|
{
|
|
const struct exception_table_entry *extab;
|
|
|
|
/* determine if the fault lay during a memcpy_user or a memset_user */
|
|
if (__frame->lr == (unsigned long) &__memset_user_error_lr &&
|
|
(unsigned long) &memset <= pc && pc < (unsigned long) &__memset_end
|
|
) {
|
|
/* the fault occurred in a protected memset
|
|
* - we search for the return address (in LR) instead of the program counter
|
|
* - it was probably during a clear_user()
|
|
*/
|
|
return (unsigned long) &__memset_user_error_handler;
|
|
}
|
|
|
|
if (__frame->lr == (unsigned long) &__memcpy_user_error_lr &&
|
|
(unsigned long) &memcpy <= pc && pc < (unsigned long) &__memcpy_end
|
|
) {
|
|
/* the fault occurred in a protected memset
|
|
* - we search for the return address (in LR) instead of the program counter
|
|
* - it was probably during a copy_to/from_user()
|
|
*/
|
|
return (unsigned long) &__memcpy_user_error_handler;
|
|
}
|
|
|
|
extab = search_exception_tables(pc);
|
|
if (extab)
|
|
return extab->fixup;
|
|
|
|
return 0;
|
|
|
|
} /* end search_exception_table() */
|