Re: [PATCH v2 08/11] uprobes: Change handle_trampoline() to flush the frames invalidated by longjmp()

[Srikar Dronamraju]

> Change handle_trampoline() to unwind ->return_instances until we know
> that the next chain is alive or NULL, this ensures that the current
> chain is the last we need to report and free.
> 
> Alternatively, every return_instance could use unique trampoline_vaddr,
> in this case we could use it as a key. And this could solve the problem
> with sigaltstack() automatically.
> 
> But this approach needs more changes, and it puts the "hard" limit on
> MAX_URETPROBE_DEPTH. Plus it can not solve another problem partially
> fixed by the next patch.
> 
> Note: this change has no effect on !x86, the arch-agnostic version of
> arch_uretprobe_is_alive() just returns "true".
> 
> TODO: as documented by the previous change, arch_uretprobe_is_alive()
> can be fooled by sigaltstack/etc.
> 
> Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>

Looks good to me.

Acked-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>

-- 
Thanks and Regards
Srikar Dronamraju

--
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/