[PATCH] Fix SAK_work workqueue initialization.

Somewhere in the rewrite of the work queues my cleanup of SAK handling
got broken.  Maybe I didn't retest it properly or possibly the API
was changing so fast I missed something.  Regardless currently
triggering a SAK now generates an ugly BUG_ON and kills the kernel.

Thanks to Alexey Dobriyan <adobriyan@openvz.org> for spotting this.

This modifies the use of SAK_work to initialize it when the data
structure it resides in is initialized, and to simply call
schedule_work when we need to generate a SAK.  I update both
data structures that have a SAK_work member for consistency.

All of the old PREPARE_WORK calls that are now gone.

If we call schedule_work again before it has processed it
has generated the first SAK it will simply ignore the duplicate
schedule_work request.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/char/keyboard.c b/drivers/char/keyboard.c
index c654a3e0c697b36f008b934a8ed276bb6c110373..cb8d691576da5c30a084db075686c7286158b048 100644 (file)
--- a/drivers/char/keyboard.c
+++ b/drivers/char/keyboard.c
@@ -596,7 +596,6 @@ static void fn_spawn_con(struct vc_data *vc)
 static void fn_SAK(struct vc_data *vc)
 {
        struct work_struct *SAK_work = &vc_cons[fg_console].SAK_work;
-       PREPARE_WORK(SAK_work, vc_SAK);
        schedule_work(SAK_work);
 }
 

diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index 3757610b7835d4952e992563821293e6cc781fcd..be73c80d699d5edc4570a5e09c83af3727bc333d 100644 (file)
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -89,7 +89,6 @@ static struct sysrq_key_op sysrq_loglevel_op = {
 static void sysrq_handle_SAK(int key, struct tty_struct *tty)
 {
        struct work_struct *SAK_work = &vc_cons[fg_console].SAK_work;
-       PREPARE_WORK(SAK_work, vc_SAK);
        schedule_work(SAK_work);
 }
 static struct sysrq_key_op sysrq_SAK_op = {

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 65672c57470b87282c3f4a73d261564310ca5565..5289254e7ab3f1e0d0fdfbf48e411e07fdc9c31a 100644 (file)
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -3442,7 +3442,6 @@ void do_SAK(struct tty_struct *tty)
 {
        if (!tty)
                return;
-       PREPARE_WORK(&tty->SAK_work, do_SAK_work);
        schedule_work(&tty->SAK_work);
 }
 
@@ -3568,7 +3567,7 @@ static void initialize_tty_struct(struct tty_struct *tty)
        mutex_init(&tty->atomic_write_lock);
        spin_lock_init(&tty->read_lock);
        INIT_LIST_HEAD(&tty->tty_files);
-       INIT_WORK(&tty->SAK_work, NULL);
+       INIT_WORK(&tty->SAK_work, do_SAK_work);
 }
 
 /*

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 94ce3e7fc9e419be797bcd46647586d30a4457b5..c3f8e383933bbb957ffd2f50982558eb5cf08b81 100644 (file)
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -2635,6 +2635,7 @@ static int __init con_init(void)
         */
        for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
                vc_cons[currcons].d = vc = alloc_bootmem(sizeof(struct vc_data));
+               INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
                visual_init(vc, currcons, 1);
                vc->vc_screenbuf = (unsigned short *)alloc_bootmem(vc->vc_screenbuf_size);
                vc->vc_kmalloced = 0;