diff options
| author | Nick Piggin | 2008-02-06 01:37:04 -0800 |
|---|---|---|
| committer | Linus Torvalds | 2008-02-06 10:41:04 -0800 |
| commit | b0940003f25dd3d2c54c4879809a432a35197f54 (patch) | |
| tree | 13337fe5d5a758f4bf89510e81554a25fce19053 /drivers/char | |
| parent | 5bd91f18be2fc0dd0384fbfca6d3cdd79a8050dd (diff) | |
vt: bitlock fix
vt is missing a memory barrier to close the critical section. Use a real
spinlock for this.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/vt.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/char/vt.c b/drivers/char/vt.c index 7a5badfb7d84..367be9175061 100644 --- a/drivers/char/vt.c +++ b/drivers/char/vt.c @@ -2400,13 +2400,15 @@ static void vt_console_print(struct console *co, const char *b, unsigned count) { struct vc_data *vc = vc_cons[fg_console].d; unsigned char c; - static unsigned long printing; + static DEFINE_SPINLOCK(printing_lock); const ushort *start; ushort cnt = 0; ushort myx; /* console busy or not yet initialized */ - if (!printable || test_and_set_bit(0, &printing)) + if (!printable) + return; + if (!spin_trylock(&printing_lock)) return; if (kmsg_redirect && vc_cons_allocated(kmsg_redirect - 1)) @@ -2481,7 +2483,7 @@ static void vt_console_print(struct console *co, const char *b, unsigned count) notify_update(vc); quit: - clear_bit(0, &printing); + spin_unlock(&printing_lock); } static struct tty_driver *vt_console_device(struct console *c, int *index) |