Re: [PATCH v2] x86_64, vmcoreinfo: Append 'page_offset_base' to vmcoreinfo

From: Bhupesh Sharma
Date: Tue Nov 27 2018 - 23:26:41 EST


On Wed, Nov 28, 2018 at 7:27 AM Baoquan He <bhe@xxxxxxxxxx> wrote:
>
> On 11/27/18 at 04:39pm, Kees Cook wrote:
> > >> >> diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
> > >> >> index 4c8acdfdc5a7..6161d77c5bfb 100644
> > >> >> --- a/arch/x86/kernel/machine_kexec_64.c
> > >> >> +++ b/arch/x86/kernel/machine_kexec_64.c
> > >> >> @@ -356,6 +356,9 @@ void arch_crash_save_vmcoreinfo(void)
> > >> >> VMCOREINFO_SYMBOL(init_top_pgt);
> > >> >> vmcoreinfo_append_str("NUMBER(pgtable_l5_enabled)=%d\n",
> > >> >> pgtable_l5_enabled());
> > >> >> +#ifdef CONFIG_RANDOMIZE_BASE
> >
> > Okay, gotcha. In that case, shouldn't this be CONFIG_RANDOMIZE_MEMORY?
>
> And yes, if we only care about KASLR, it should be
> CONFIG_RANDOMIZE_MEMORY, but not CONFIG_RANDOMIZE_BASE.
>

Have you tried building the changes with 'make allmodconfig' with all
the different CONFIG options you have suggested so far?