On 14 February 2017 at 22:42, Mathias Krause <mini...@googlemail.com> wrote: > On 14 February 2017 at 19:13, H. Peter Anvin <h...@zytor.com> wrote: >> On 02/12/17 13:12, Mathias Krause wrote: >>> As of commit a5c2a893dbd4 ("x86, 386 removal: Remove >>> CONFIG_X86_WP_WORKS_OK") the kernel won't boot if CR0.WP isn't working >>> correctly. This makes a process reading this file always see "wp : yes" >>> here -- otherwise there would be no process to begin with ;) >>> >>> As this status line in /proc/cpuinfo serves no purpose for quite some >>> time now, get rid of it. >>> >>> Cc: Borislav Petkov <b...@alien8.de> >>> Cc: H. Peter Anvin <h...@linux.intel.com> >>> Signed-off-by: Mathias Krause <mini...@googlemail.com> >>> --- >>> arch/x86/kernel/cpu/proc.c | 6 ++---- >>> 1 file changed, 2 insertions(+), 4 deletions(-) >>> >>> diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c >>> index 6df621ae62a7..c6c5217a7980 100644 >>> --- a/arch/x86/kernel/cpu/proc.c >>> +++ b/arch/x86/kernel/cpu/proc.c >>> @@ -30,8 +30,7 @@ static void show_cpuinfo_misc(struct seq_file *m, struct >>> cpuinfo_x86 *c) >>> "coma_bug\t: %s\n" >>> "fpu\t\t: %s\n" >>> "fpu_exception\t: %s\n" >>> - "cpuid level\t: %d\n" >>> - "wp\t\t: yes\n", >>> + "cpuid level\t: %d\n", >>> static_cpu_has_bug(X86_BUG_FDIV) ? "yes" : "no", >>> static_cpu_has_bug(X86_BUG_F00F) ? "yes" : "no", >>> static_cpu_has_bug(X86_BUG_COMA) ? "yes" : "no", >>> @@ -45,8 +44,7 @@ static void show_cpuinfo_misc(struct seq_file *m, struct >>> cpuinfo_x86 *c) >>> seq_printf(m, >>> "fpu\t\t: yes\n" >>> "fpu_exception\t: yes\n" >>> - "cpuid level\t: %d\n" >>> - "wp\t\t: yes\n", >>> + "cpuid level\t: %d\n", >>> c->cpuid_level); >>> } >>> #endif >>> >> >> Potential userspace breakage, which is why the line was left in the >> first place despite its value now being hard-coded. Removing it will >> save a whopping 9 bytes of kernel rodata; this is a very small price to >> pay for guaranteeing continued compatibility. > > Indeed. That's why I've separated the removal into an extra patch -- > to make it easier not to take it. > >> >> Nacked-by: H. Peter Anvin <h...@zytor.com> > > Do you want me to send the series again without this patch and patch > #6 (Geert took it already) or are you okay with sorting them out > yourself? >
Ping... Peter, what's your preference here? Mathias