diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2016-11-08 14:56:20 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2016-11-16 18:50:51 +0100 |
| commit | a4023f682739439b434165b54af7cb3676a4766e (patch) | |
| tree | ef2638d37291c56d972f20b69c59a6dee9292c18 /arch/arm64/kernel | |
| parent | arm64: split thread_info from task stack (diff) | |
| download | linux-a4023f682739439b434165b54af7cb3676a4766e.tar.xz linux-a4023f682739439b434165b54af7cb3676a4766e.zip | |
arm64: Add hypervisor safe helper for checking constant capabilities
The hypervisor may not have full access to the kernel data structures
and hence cannot safely use cpus_have_cap() helper for checking the
system capability. Add a safe helper for hypervisors to check a constant
system capability, which *doesn't* fall back to checking the bitmap
maintained by the kernel. With this, make the cpus_have_cap() only
check the bitmask and force constant cap checks to use the new API
for quicker checks.
Cc: Robert Ritcher <rritcher@cavium.com>
Cc: Tirumalesh Chalamarla <tchalamarla@cavium.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 2 | ||||
| -rw-r--r-- | arch/arm64/kernel/process.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index c02504ea304b..fc2bd1926607 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1102,5 +1102,5 @@ void __init setup_cpu_features(void) static bool __maybe_unused cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused) { - return (cpus_have_cap(ARM64_HAS_PAN) && !cpus_have_cap(ARM64_HAS_UAO)); + return (cpus_have_const_cap(ARM64_HAS_PAN) && !cpus_have_const_cap(ARM64_HAS_UAO)); } diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index a98b743631c5..a3a2816ba73a 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -283,7 +283,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start, memset(childregs, 0, sizeof(struct pt_regs)); childregs->pstate = PSR_MODE_EL1h; if (IS_ENABLED(CONFIG_ARM64_UAO) && - cpus_have_cap(ARM64_HAS_UAO)) + cpus_have_const_cap(ARM64_HAS_UAO)) childregs->pstate |= PSR_UAO_BIT; p->thread.cpu_context.x19 = stack_start; p->thread.cpu_context.x20 = stk_sz; |