diff options
Diffstat (limited to 'arch/frv/mm/extable.c')
| -rw-r--r-- | arch/frv/mm/extable.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/arch/frv/mm/extable.c b/arch/frv/mm/extable.c new file mode 100644 index 000000000..8863d6c1d --- /dev/null +++ b/arch/frv/mm/extable.c @@ -0,0 +1,49 @@ +/* + * linux/arch/frv/mm/extable.c + */ + +#include <linux/module.h> +#include <linux/spinlock.h> +#include <asm/uaccess.h> + +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; + + +/*****************************************************************************/ +/* + * 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() */ |