PATCH 2.5.2.6: fix up serial, sysrq

From: Jeff Garzik <[email protected]>

The kdev_none change might not be correct, please check.

Indeed, I would say it is not.

- if (!is_local_disk(sb->s_dev) && MAJOR(sb->s_dev))
+ if (!is_local_disk(sb->s_dev) && !kdev_none(sb->s_dev))
go_sync(sb, remount_flag);

Without studying the surrounding code, I conjecture that the test MAJOR(sb->s_dev) was meant to exclude anonymous devices (with major 0), not only NODEV.

Andries