/dev/mem: allow rewinding

commit dcefafb6 ("/dev/mem: dont allow seek to last page") inadvertently
disabled rewinding on /dev/mem.

This broke x86info for example.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 47c8452..9cdbadc 100644 (file)
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -710,11 +710,6 @@ static loff_t memory_lseek(struct file *file, loff_t offset, int orig)
        switch (orig) {
        case SEEK_CUR:
                offset += file->f_pos;
-               if ((unsigned long long)offset <
-                   (unsigned long long)file->f_pos) {
-                       ret = -EOVERFLOW;
-                       break;
-               }
        case SEEK_SET:
                /* to avoid userland mistaking f_pos=-9 as -EBADF=-9 */
                if ((unsigned long long)offset >= ~0xFFFULL) {