Messages in this thread | | | From | "Manfred Spraul" <> | Subject | Re: [PATCH #2] console lock grabbed too early in printk... | Date | Sun, 2 Jul 2000 13:13:32 +0200 |
| |
From: "Chris Lattner" <sabre@skylab.org> > The sequence of events goes like this: > 1. printk of args to sys_access > 2. printk grabs the console lock > 3. vfprintf is called, but one of the strings (the filename) resides on a > page that hasn't been materialized yet. > 4. page fault occurs > 5. page fault handler runs, maps page > 6. Page mapping causes printk > 7. printk causes deadlock as it attempts to grab the console lock that the > kernel thread already has... > 8. we spin with disabled interrupt 9. the nmi watchdog detects that 10. it breaks the console lock, and prints an emergency message.
I really don't think we should add a special case for the console lock: it's a very rare combination, and we have the nmi oopser for general deadlocks.
-- Manfred
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |