Re: [RFC] [Patch 0/21] Non disruptive application core dump infrastructure

From: Tejun Heo
Date: Tue Dec 14 2010 - 11:29:23 EST


Hello, Linus.

On 12/14/2010 05:19 PM, Linus Torvalds wrote:
> On Tue, Dec 14, 2010 at 8:03 AM, Tejun Heo <tj@xxxxxxxxxx> wrote:
>>
>> I think a better way would be adding a ptrace attach which is nestable
>> and doesn't have the nasty side effect caused by the interactions
>> between the implicit SIGSTOP and group stop.
>
> Don't we already nest at least to some degree? At least you can strace
> a gdb session or another strace, no?

Yes, it depends on what the 'nesting' means. I was thinking about
gcore'ing or attching gdb to an already strace'd process. This might
not be strictly necessary but for ptrace attach to be transparent, we
need another PTRACE_* call anyway as PTRACE_ATTACH implies SIGSTOP and
having nestable attach would be beneficial in several use cases
including using debugging tools nested and allowing userland
checkpointing of debugging sessions.

Thanks.

--
tejun
--
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/