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| author | Ard Biesheuvel <ardb@kernel.org> | 2021-03-23 17:10:09 +0100 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2021-03-23 17:13:32 +0100 |
| commit | 34579a08c08ed8e3b352e31e1d5db7ba665e6db6 (patch) | |
| tree | c570504c721a2037cde1b44089b405555667bb2b | |
| parent | 0b68d68e39eee4449201c4cf8d7540e011b998ec (diff) | |
| download | linux-34579a08c08ed8e3b352e31e1d5db7ba665e6db6.tar.gz | |
arm64: random: use hyp entropy under pkvm
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| -rw-r--r-- | arch/arm64/include/asm/archrandom.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/archrandom.h b/arch/arm64/include/asm/archrandom.h index 09e43272ccb0a..7fdd39004ac75 100644 --- a/arch/arm64/include/asm/archrandom.h +++ b/arch/arm64/include/asm/archrandom.h @@ -6,8 +6,10 @@ #include <linux/arm-smccc.h> #include <linux/bug.h> +#include <linux/jump_label.h> #include <linux/kernel.h> #include <asm/cpufeature.h> +#include <asm/virt.h> #define ARM_SMCCC_TRNG_MIN_VERSION 0x10000UL @@ -52,10 +54,25 @@ static inline bool __must_check arch_get_random_int(unsigned int *v) return false; } +// TODO define this in a header without getting into #include hell +#define PKVM_get_entropy \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + 21) + static inline bool __must_check arch_get_random_seed_long(unsigned long *v) { struct arm_smccc_res res; + if (static_branch_likely(&kvm_protected_mode_initialized)) { + arm_smccc_1_1_hvc(PKVM_get_entropy, 64, &res); + if ((int)res.a0 >= 0) { + *v = res.a3; + return true; + } + } + /* * We prefer the SMCCC call, since its semantics (return actual * hardware backed entropy) is closer to the idea behind this |