[RFC PATCH V3 02/11] x86/HV: Initialize shared memory boundary in the Isolation VM.
From: Tianyu Lan <hidden>
Date: 2021-05-30 15:06:56
Also in:
linux-arch, linux-hyperv, linux-iommu, linux-scsi, lkml, netdev
Subsystem:
generic include/asm header files, hyper-v/azure core and drivers, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Arnd Bergmann, "K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Tianyu Lan <redacted> Hyper-V also exposes shared memory boundary via cpuid HYPERV_CPUID_ISOLATION_CONFIG and store it in the shared_gpa_boundary of ms_hyperv struct. This prepares to share memory with host for SNP guest. Signed-off-by: Tianyu Lan <redacted> --- arch/x86/kernel/cpu/mshyperv.c | 2 ++ include/asm-generic/mshyperv.h | 12 +++++++++++- 2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 22f13343b5da..d1ca36224657 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c@@ -320,6 +320,8 @@ static void __init ms_hyperv_init_platform(void) if (ms_hyperv.priv_high & HV_ISOLATION) { ms_hyperv.isolation_config_a = cpuid_eax(HYPERV_CPUID_ISOLATION_CONFIG); ms_hyperv.isolation_config_b = cpuid_ebx(HYPERV_CPUID_ISOLATION_CONFIG); + ms_hyperv.shared_gpa_boundary = + (u64)1 << ms_hyperv.shared_gpa_boundary_bits; pr_info("Hyper-V: Isolation Config: Group A 0x%x, Group B 0x%x\n", ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index 3ae56a29594f..2914e27b0429 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h@@ -34,8 +34,18 @@ struct ms_hyperv_info { u32 max_vp_index; u32 max_lp_index; u32 isolation_config_a; - u32 isolation_config_b; + union { + u32 isolation_config_b; + struct { + u32 cvm_type : 4; + u32 Reserved11 : 1; + u32 shared_gpa_boundary_active : 1; + u32 shared_gpa_boundary_bits : 6; + u32 Reserved12 : 20; + }; + }; void __percpu **ghcb_base; + u64 shared_gpa_boundary; }; extern struct ms_hyperv_info ms_hyperv;
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2.25.1