In hv_common_cpu_init(), the per-CPU hypercall input/output pages need to be marked as decrypted (shared) for confidential VM isolation types. This is already done for SNP and TDX isolation; extend the same handling to Arm CCA Realm guests so that the host hypervisor can access the shared hypercall buffers.
is_realm_world() is only declared in arch/arm64/include/asm/rsi.h, so using it directly in the arch-neutral drivers/hv/hv_common.c would break the x86 build. Introduce a Hyper-V-specific helper following the established hv_isolation_type_snp() / hv_isolation_type_tdx() pattern. On architectures other than arm64 the weak default keeps the existing behaviour. Signed-off-by: Kameron Carr <[email protected]> --- arch/arm64/hyperv/mshyperv.c | 5 +++++ drivers/hv/hv_common.c | 9 ++++++++- include/asm-generic/mshyperv.h | 1 + 3 files changed, 14 insertions(+), 1 deletion(-) diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c index 08fec82691683..b595b2b9bdbbb 100644 --- a/arch/arm64/hyperv/mshyperv.c +++ b/arch/arm64/hyperv/mshyperv.c @@ -208,3 +208,8 @@ bool hv_is_hyperv_initialized(void) return hyperv_initialized; } EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized); + +bool hv_isolation_type_cca(void) +{ + return is_realm_world(); +} diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index 6b67ac6167891..010c7d98b5de1 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -499,7 +499,8 @@ int hv_common_cpu_init(unsigned int cpu) } if (!ms_hyperv.paravisor_present && - (hv_isolation_type_snp() || hv_isolation_type_tdx())) { + (hv_isolation_type_snp() || hv_isolation_type_tdx() || + hv_isolation_type_cca())) { ret = set_memory_decrypted((unsigned long)mem, pgcount); if (ret) { /* It may be unsafe to free 'mem' */ @@ -666,6 +667,12 @@ bool __weak hv_isolation_type_tdx(void) } EXPORT_SYMBOL_GPL(hv_isolation_type_tdx); +bool __weak hv_isolation_type_cca(void) +{ + return false; +} +EXPORT_SYMBOL_GPL(hv_isolation_type_cca); + void __weak hv_setup_vmbus_handler(void (*handler)(void)) { } diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index bf601d67cecb9..1fa79abce743c 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -79,6 +79,7 @@ u64 hv_do_fast_hypercall16(u16 control, u64 input1, u64 input2); bool hv_isolation_type_snp(void); bool hv_isolation_type_tdx(void); +bool hv_isolation_type_cca(void); /* * On architectures where Hyper-V doesn't support AEOI (e.g., ARM64), -- 2.45.4
