[PATCH] fix arm26 THREAD_SIZE

arm26 currently has a 256 kB THREAD_SIZE (sic).

Looking at the comment in the code, this seems to be based on a
misunderstanding.

The comment says:
this needs attention (see kernel/fork.c which gets a nice div by zero if
this is lower than 8*32768

kernel/fork.c does:
  max_threads = mempages / (8 * THREAD_SIZE / PAGE_SIZE)

Therefore, a division by 0 is impossible for all reasonable cases with
THREAD_SIZE >= PAGE_SIZE.

Since the minimum PAGE_SIZE Linux uses on the arm26 architecture is 16k,
PAGE_SIZE should be sufficient for THREAD_SIZE.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Ian Molton <spyro@f2s.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/include/asm-arm26/thread_info.h b/include/asm-arm26/thread_info.h
index a65e58a..9b367eb 100644 (file)
--- a/include/asm-arm26/thread_info.h
+++ b/include/asm-arm26/thread_info.h
@@ -80,8 +80,7 @@ static inline struct thread_info *current_thread_info(void)
        return (struct thread_info *)(sp & ~0x1fff);
 }
 
-/* FIXME - PAGE_SIZE < 32K */
-#define THREAD_SIZE            (8*32768) // FIXME - this needs attention (see kernel/fork.c which gets a nice div by zero if this is lower than 8*32768
+#define THREAD_SIZE    PAGE_SIZE
 #define task_pt_regs(task) ((struct pt_regs *)(task_stack_page(task) + THREAD_SIZE - 8) - 1)
 
 extern struct thread_info *alloc_thread_info(struct task_struct *task);