Re: ftrace introduces instability into kernel 2.6.27(-rc2,-rc3)

From: Benjamin Herrenschmidt
Date: Wed Aug 20 2008 - 17:52:25 EST



> > As you can see, it restores r1 -before- it pops r24..r31 off
> > the stack ! I let you imagine what happens if an interrupt happens
> > just in between those two instructions (mr and lmw). We don't do
> > redzones on our ABI, so basically, the registers end up corrupted
> > by the interrupt.
>
> Ouch! You've disassembled this without -pg too, and it does not have this
> bug? What version of gcc do you have?

Oops, should have mentioned it ;-)

4.2.3 (Ubuntu 4.2.3-2ubuntu7)

Ben.


--
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/