On Wed, 24 May 2017, Steven Rostedt wrote:
> The trampolines uses the module allocation, and it appears, that needs
> to become rw before freeing again.
Indeed. I realized that when enabling more debug options, which led to a
reliable triple fault.
How intuitive.
> I applied this patch, and it appears to fix the bug for me.
It fixes the bug, but ...
> -static inline void tramp_free(void *tramp)
> +static inline void tramp_free(void *tramp, int size)
> {
> + int npages;
> +
> + npages = PAGE_ALIGN(size) >> PAGE_SHIFT;
For correctness sake this wants
set_memory_nx(...);
as well.
> + set_memory_rw((unsigned long)tramp, npages);
> module_memfree(tramp);
> }
I'll clean that up and post a V2.
Thanks,
tglx
