Valgrind as init

[Aidan Thornton]

On Wed, Jun 8, 2011 at 9:39 PM, Scott James Remnant <scott at netsplit.com> wrote:
> The problem with valgrind is the same as the general problem with gdb; init
> needs to be pid 1, and these processes then can't trace it/emulate it.
> Scott

Hi,

This all seems quite familiar. I know initng used to have a kernel
patch you could apply to work around this issue, though that's long
since out of date. Not sure if I ever ran valgrind on pid 1 though. In
fact, I think the big problem was that if it detected a serious enough
memory access violation, valgrind forcibly terminated init, bypassing
any SIGSEGV handler and causing a kernel panic due to pid 1 exiting.

Basically: you don't want to do that. If you need to do so, I suggest
using a VM with the console attached to somewhere that the messages
will survive a kernel panic within the VM. If you can somehow manage
to test whatever it is you need without running upstart as pid 1 that
will make your life a lot easier.

Hope that helps,
Aidan

(Apologies for any duplicates, I sent this from the wrong address.)