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arm64: cpufeature: Relocate PAN emulation report 

The PAN emulation notification was only happening for non-boot CPUs
if CPU capabilities had already been configured. This seems to be the
wrong place, as it's system-wide and isn't attached to capabilities,
so its reporting didn't normally happen. Instead, report it once from
the boot CPU.

Before (missing PAN emulation report):

 SMP: Total of 4 processors activated.
 CPU features: detected feature: 32-bit EL0 Support
 CPU features: detected feature: Kernel page table isolation (KPTI)
 CPU: All CPU(s) started at EL2

After:

 SMP: Total of 4 processors activated.
 CPU features: detected feature: 32-bit EL0 Support
 CPU features: detected feature: Kernel page table isolation (KPTI)
 CPU features: emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching
 CPU: All CPU(s) started at EL2

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
hifive-unleashed-5.1
Kees Cook 2018-02-21 10:18:21 -08:00 committed by Will Deacon
parent 6141ac1c27
commit 2e6f549fe9
1 changed files with 3 additions and 3 deletions
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6
arch/arm64/kernel/cpufeature.c
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@ -1335,9 +1335,6 @@ static void verify_local_cpu_capabilities(void)
if (system_supports_sve())
verify_sve_features();
if (system_uses_ttbr0_pan())
pr_info("Emulating Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
}
void check_local_cpu_capabilities(void)
@ -1396,6 +1393,9 @@ void __init setup_cpu_features(void)
if (system_supports_32bit_el0())
setup_elf_hwcaps(compat_elf_hwcaps);
if (system_uses_ttbr0_pan())
pr_info("emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching\n");
sve_setup();
/* Advertise that we have computed the system capabilities */