Re: [PATCH v3 2/4] x86/traps: Print non-canonical address on #GP

[Ingo Molnar <mingo@kernel.org>]

* Jann Horn <jannh@google.com> wrote:

> You mean something like this?
> 
> ========================
> diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
> index 9b23c4bda243..16a6bdaccb51 100644
> --- a/arch/x86/kernel/traps.c
> +++ b/arch/x86/kernel/traps.c
> @@ -516,32 +516,36 @@ dotraplinkage void do_bounds(struct pt_regs
> *regs, long error_code)
>   * On 64-bit, if an uncaught #GP occurs while dereferencing a non-canonical
>   * address, return that address.
>   */
> -static unsigned long get_kernel_gp_address(struct pt_regs *regs)
> +static bool get_kernel_gp_address(struct pt_regs *regs, unsigned long *addr,
> +                                          bool *non_canonical)

Yeah, that's pretty much the perfect end result!

> I guess that could potentially be useful if a #GP is triggered by
> something like an SSE alignment error? I'll add it in unless someone
> else complains.

Yeah - also it's correct information about the context of the fault, so 
it probably cannot *hurt*, and will allow us to debug/validate everything 
in this area faster.

> > > +#define GPFSTR "general protection fault"
> > >  dotraplinkage void
> >
> > Please separate macro and function definitions by an additional newline.
> 
> Will change it.

Thanks!

	Ingo