| Message ID | 20201203223217.1238899-1-arnd@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: cpufeature: fix unused function warning | expand |
On Thu, Dec 03, 2020 at 11:32:11PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@arndb.de> > > The __system_matches_cap() function is now only used in an #ifdef > section: > > arch/arm64/kernel/cpufeature.c:2649:13: error: unused function '__system_matches_cap' [-Werror,-Wunused-function] > > Move it into that #ifdef section. > > Fixes: 7cf283c7bd62 ("arm64: uaccess: remove redundant PAN toggling") > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > arch/arm64/kernel/cpufeature.c | 36 ++++++++++++++++------------------ > 1 file changed, 17 insertions(+), 19 deletions(-) Acked-by: Will Deacon <will@kernel.org> We can probably go further and remove the helper altogether as I don't think it really helps has_generic_auth(), but this should fix the warning. Will
On Fri, Dec 04, 2020 at 09:59:10AM +0000, Will Deacon wrote: > On Thu, Dec 03, 2020 at 11:32:11PM +0100, Arnd Bergmann wrote: > > From: Arnd Bergmann <arnd@arndb.de> > > > > The __system_matches_cap() function is now only used in an #ifdef > > section: > > > > arch/arm64/kernel/cpufeature.c:2649:13: error: unused function '__system_matches_cap' [-Werror,-Wunused-function] > > > > Move it into that #ifdef section. > > > > Fixes: 7cf283c7bd62 ("arm64: uaccess: remove redundant PAN toggling") > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> I already queued a fix from Mark: 701f49065e68 ("arm64: mark __system_matches_cap as __maybe_unused"). > Acked-by: Will Deacon <will@kernel.org> > > We can probably go further and remove the helper altogether as I don't > think it really helps has_generic_auth(), but this should fix the warning. We could replace the ARM64_HAS_GENERIC_AUTH checks with a single helper function that tests for ARM64_HAS_GENERIC_AUTH_ARCH or ARM64_HAS_GENERIC_AUTH_IMP_DEF. Or you had a different idea?
On Mon, Dec 07, 2020 at 06:19:31PM +0000, Catalin Marinas wrote: > On Fri, Dec 04, 2020 at 09:59:10AM +0000, Will Deacon wrote: > > On Thu, Dec 03, 2020 at 11:32:11PM +0100, Arnd Bergmann wrote: > > > From: Arnd Bergmann <arnd@arndb.de> > > > > > > The __system_matches_cap() function is now only used in an #ifdef > > > section: > > > > > > arch/arm64/kernel/cpufeature.c:2649:13: error: unused function '__system_matches_cap' [-Werror,-Wunused-function] > > > > > > Move it into that #ifdef section. > > > > > > Fixes: 7cf283c7bd62 ("arm64: uaccess: remove redundant PAN toggling") > > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > > I already queued a fix from Mark: 701f49065e68 ("arm64: mark > __system_matches_cap as __maybe_unused"). > > > Acked-by: Will Deacon <will@kernel.org> > > > > We can probably go further and remove the helper altogether as I don't > > think it really helps has_generic_auth(), but this should fix the warning. > > We could replace the ARM64_HAS_GENERIC_AUTH checks with a single helper > function that tests for ARM64_HAS_GENERIC_AUTH_ARCH or > ARM64_HAS_GENERIC_AUTH_IMP_DEF. Or you had a different idea? I was just thinking something like below, although it's a bit annoying that we can't use cpucap_multi_entry_cap_matches() here afaict. Will --->8 diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 39138f6d3ba2..32a138ce0a92 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -155,8 +155,6 @@ EXPORT_SYMBOL(cpu_hwcap_keys); static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap); -static bool __system_matches_cap(unsigned int n); - /* * NOTE: Any changes to the visibility of features should be kept in * sync with the documentation of the CPU feature register ABI. @@ -1652,8 +1650,13 @@ static bool has_address_auth_metacap(const struct arm64_cpu_capabilities *entry, static bool has_generic_auth(const struct arm64_cpu_capabilities *entry, int __unused) { - return __system_matches_cap(ARM64_HAS_GENERIC_AUTH_ARCH) || - __system_matches_cap(ARM64_HAS_GENERIC_AUTH_IMP_DEF); + const struct arm64_cpu_capabilities *cap_arch, *cap_impdef; + + cap_arch = cpu_hwcaps_ptrs[ARM64_HAS_GENERIC_AUTH_ARCH]; + cap_impdef = cpu_hwcaps_ptrs[ARM64_HAS_GENERIC_AUTH_IMP_DEF]; + + return cap_arch->matches(cap_arch, SCOPE_SYSTEM) || + cap_impdef->matches(cap_impdef, SCOPE_SYSTEM); } #endif /* CONFIG_ARM64_PTR_AUTH */ @@ -2637,23 +2640,6 @@ bool this_cpu_has_cap(unsigned int n) return false; } -/* - * This helper function is used in a narrow window when, - * - The system wide safe registers are set with all the SMP CPUs and, - * - The SYSTEM_FEATURE cpu_hwcaps may not have been set. - * In all other cases cpus_have_{const_}cap() should be used. - */ -static bool __maybe_unused __system_matches_cap(unsigned int n) -{ - if (n < ARM64_NCAPS) { - const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n]; - - if (cap) - return cap->matches(cap, SCOPE_SYSTEM); - } - return false; -} - void cpu_set_feature(unsigned int num) { WARN_ON(num >= MAX_CPU_FEATURES);
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 6bdb03400581..2c4e526c6e78 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -156,8 +156,6 @@ EXPORT_SYMBOL(cpu_hwcap_keys); static void cpu_enable_cnp(struct arm64_cpu_capabilities const *cap); -static bool __system_matches_cap(unsigned int n); - /* * NOTE: Any changes to the visibility of features should be kept in * sync with the documentation of the CPU feature register ABI. @@ -1617,6 +1615,23 @@ static void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused) #endif /* CONFIG_ARM64_RAS_EXTN */ #ifdef CONFIG_ARM64_PTR_AUTH +/* + * This helper function is used in a narrow window when, + * - The system wide safe registers are set with all the SMP CPUs and, + * - The SYSTEM_FEATURE cpu_hwcaps may not have been set. + * In all other cases cpus_have_{const_}cap() should be used. + */ +static bool __system_matches_cap(unsigned int n) +{ + if (n < ARM64_NCAPS) { + const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n]; + + if (cap) + return cap->matches(cap, SCOPE_SYSTEM); + } + return false; +} + static bool has_address_auth_cpucap(const struct arm64_cpu_capabilities *entry, int scope) { int boot_val, sec_val; @@ -2640,23 +2655,6 @@ bool this_cpu_has_cap(unsigned int n) return false; } -/* - * This helper function is used in a narrow window when, - * - The system wide safe registers are set with all the SMP CPUs and, - * - The SYSTEM_FEATURE cpu_hwcaps may not have been set. - * In all other cases cpus_have_{const_}cap() should be used. - */ -static bool __system_matches_cap(unsigned int n) -{ - if (n < ARM64_NCAPS) { - const struct arm64_cpu_capabilities *cap = cpu_hwcaps_ptrs[n]; - - if (cap) - return cap->matches(cap, SCOPE_SYSTEM); - } - return false; -} - void cpu_set_feature(unsigned int num) { WARN_ON(num >= MAX_CPU_FEATURES);