Messages in this thread | | | Subject | Re: [RFC][PATCH] x86: Make x32 syscall support conditional on a kernel parameter | From | Ben Hutchings <> | Date | Thu, 06 Nov 2014 16:25:13 +0000 |
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On Thu, 2014-11-06 at 09:02 +0100, Geert Uytterhoeven wrote: > On Thu, Nov 6, 2014 at 4:53 AM, Ben Hutchings <ben@decadent.org.uk> wrote: [...] > > diff --git a/arch/x86/kernel/syscall_64.c b/arch/x86/kernel/syscall_64.c > > index 4ac730b..7a6e66f 100644 > > --- a/arch/x86/kernel/syscall_64.c > > +++ b/arch/x86/kernel/syscall_64.c > > > +static int __init x32_enable(void) > > +{ > > + BUG_ON(system_call_fast_compare_end - system_call_fast_compare != 10); > > + BUG_ON(system_call_trace_compare_end - system_call_trace_compare != 10); > > + BUG_ON(system_call_mask_compare_end - system_call_mask_compare != 10); > > BUILD_BUG_ON
No, these can't be evaluated at compile time because the symbols are external.
> > + > > + if (x32_enabled) { > > + text_poke_early(system_call_fast_compare, > > + system_call_mask_compare, 10); > > + text_poke_early(system_call_trace_compare, > > + system_call_mask_compare, 10); > > +#ifdef CONFIG_X86_X32_DISABLED > > + pr_info("Enabled x32 syscalls\n"); > > +#endif > > I don't think it hurts to print this unconditionally. [...]
It seemed like it would be unnecessary noise in an x32-only system.
Ben.
-- Ben Hutchings Beware of programmers who carry screwdrivers. - Leonard Brandwein [unhandled content-type:application/pgp-signature] | |