Re: OOPS in perf_mmap_close()

From: Vince Weaver
Date: Wed May 22 2013 - 23:44:49 EST



In case anyone cares, the Oops is happening here:

1a56: 48 c1 e8 0c shr $0xc,%rax
1a5a: 48 ff c0 inc %rax
> 1a5d: f0 48 29 45 60 lock sub %rax,0x60(%rbp)
1a62: 49 8b 46 40 mov 0x40(%r14),%rax

Which maps to this in perf_mmap_close() in kernel/events/core.c:

atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm);

And "user" (%rbp) is RBP: 0000000000000000, hence the problem.

I'm having trouble tracking the problem back any further as the code is a
bit covoluted and is not commented at all.

Vince
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/