On Fri, May 15, 2020 at 08:58:05AM +0530, Anshuman Khandual wrote:
> On 05/14/2020 01:06 PM, Will Deacon wrote:
> > Why is it a change? We've never reported e.g. "java" on an arm64 kernel, so
>
> We already have "java" defined in existing compat_hwcap_str[] array even
> though it might never get set in compat_elf_hwcap. AFAICS, compat_elf_hwcap
> will have the following capabilities set (at the most).
>
> Via COMPAT_ELF_HWCAP_DEFAULT
>
> 01. COMPAT_HWCAP_HALF
> 02. COMPAT_HWCAP_THUMB
> 03. COMPAT_HWCAP_FAST_MULT
> 04. COMPAT_HWCAP_EDSP
> 05. COMPAT_HWCAP_TLS
> 06. COMPAT_HWCAP_IDIV
> 07. COMPAT_HWCAP_LPAE
>
> Via setup_elf_hwcaps(compat_elf_hwcaps) <-- setup_cpu_features()
>
> 8. COMPAT_HWCAP_NEON
> 9. COMPAT_HWCAP_VFPv4
> 10. COMPAT_HWCAP_VFP
> 11. COMPAT_HWCAP_VFPv3
>
> Via arch_timer_set_evtstrm_feature()
>
> 12. COMPAT_HWCAP_EVTSTRM
>
> The code exists for "java" string to be displayed with /proc/cpuinfo but it
> may never get triggered as compat_elf_hwcap will never have JAVA capability
> unless there is a bug as you had rightly mentioned.
Fair enough, but applying this patch causes a *tonne* of warnings from
aiaiai:
+In file included from arch/arm64/include/asm/cpufeature.h:11,
+ from arch/arm64/include/asm/ptrace.h:11,
+ from arch/arm64/include/asm/irqflags.h:10,
+ from include/linux/irqflags.h:16,
+ from include/linux/spinlock.h:54,
+ from include/linux/seqlock.h:36,
+ from include/linux/time.h:6,
+ from arch/arm64/include/asm/stat.h:12,
+ from include/linux/stat.h:6,
+ from include/linux/module.h:13,
+ from drivers/media/rc/keymaps/rc-imon-mce.mod.c:1:
+arch/arm64/include/asm/hwcap.h:189:26: warning: ‘compat_hwcap2_str’ defined
but not used [-Wunused-const-variable=]
+ 189 | static const char *const compat_hwcap2_str[] = {
+ | ^~~~~~~~~~~~~~~~~
so I'm dropping this for now.
Will
