On 2012/09/14 06:10, Eric Sandeen wrote:
The stupid emergency sysrq thing was my fault (at someone else's suggestion) ;) It's caused a lot of woe, and hasn't worked for two years. Should we keep it?
It turns out that emergency thaw is useful in virtuazalition environments where a guest's filesystem can be frozen by a hypervisor controlled guest agent without the guest's users and administrator being aware of it. In such scenarios if the guest agent dies leaving a filesystem frozen we are in trouble. The guest's administrator or root user will eventually notice that writes to the filesystem that was frozen behind its back block but it has no way to figure out what is going on since we do not have check ioctls. In such cases emergency thaw is very useful. Please notice that even if we managed to restart the guest agent, in many cases it is stateless so it will not remember that a froze the filesystem. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
