diff options
| author |   Andrew Morton <akpm@osdl.org> | 2006-12-06 20:36:40 -0800 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-07 08:39:34 -0800 |
| commit | 20aa7b21b1cbd1aa3fbf5fc14da5f7484a61a824 (patch) | |
| tree | ae0e9ec484c26f29f8f5cfa863a84943c27dfe9d /include/linux | |
| parent | [PATCH] parport_pc: Add support for OX16PCI952 parallel port (diff) | |
[PATCH] probe_kernel_address() needs to do set_fs()
probe_kernel_address() purports to be generic, only it forgot to select
KERNEL_DS, so it presently won't work right on all architectures.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/uaccess.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 67918c22339c..76c3fe325101 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -65,14 +65,22 @@ static inline unsigned long __copy_from_user_nocache(void *to, * do_page_fault() doesn't attempt to take mmap_sem. This makes * probe_kernel_address() suitable for use within regions where the caller * already holds mmap_sem, or other locks which nest inside mmap_sem. + * This must be a macro because __get_user() needs to know the types of the + * args. + * + * We don't include enough header files to be able to do the set_fs(). We + * require that the probe_kernel_address() caller will do that. */ #define probe_kernel_address(addr, retval) \ ({ \ long ret; \ + mm_segment_t old_fs = get_fs(); \ \ + set_fs(KERNEL_DS); \ pagefault_disable(); \ ret = __get_user(retval, addr); \ pagefault_enable(); \ + set_fs(old_fs); \ ret; \ }) |