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? Cheers, Mathias