Commit a479c334 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: SVM: Condition sev_enabled and sev_es_enabled on CONFIG_KVM_AMD_SEV=y 



Define sev_enabled and sev_es_enabled as 'false' and explicitly #ifdef
out all of sev_hardware_setup() if CONFIG_KVM_AMD_SEV=n.  This kills
three birds at once:

  - Makes sev_enabled and sev_es_enabled off by default if
    CONFIG_KVM_AMD_SEV=n.  Previously, they could be on by default if
    CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT=y, regardless of KVM SEV
    support.

  - Hides the sev and sev_es modules params when CONFIG_KVM_AMD_SEV=n.

  - Resolves a false positive -Wnonnull in __sev_recycle_asids() that is
    currently masked by the equivalent IS_ENABLED(CONFIG_KVM_AMD_SEV)
    check in svm_sev_enabled(), which will be dropped in a future patch.

Reviewed by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: default avatarBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20210422021125.3417167-9-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 8d364a07

arch/x86/kvm/svm/sev.c

+8 −1
Original line number Diff line number Diff line
@@ -44,6 +44,7 @@ 
#define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES

#endif



#ifdef CONFIG_KVM_AMD_SEV

/* enable/disable SEV support */

static bool sev_enabled = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);

module_param_named(sev, sev_enabled, bool, 0444);
@@ -51,6 +52,10 @@ module_param_named(sev, sev_enabled, bool, 0444); 
/* enable/disable SEV-ES support */

static bool sev_es_enabled = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);

module_param_named(sev_es, sev_es_enabled, bool, 0444);

#else

#define sev_enabled false

#define sev_es_enabled false

#endif /* CONFIG_KVM_AMD_SEV */



static u8 sev_enc_bit;

static int sev_flush_asids(void);
@@ -1817,11 +1822,12 @@ void __init sev_set_cpu_caps(void) 


void __init sev_hardware_setup(void)

{

#ifdef CONFIG_KVM_AMD_SEV

	unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count;

	bool sev_es_supported = false;

	bool sev_supported = false;



	if (!IS_ENABLED(CONFIG_KVM_AMD_SEV) || !sev_enabled || !npt_enabled)

	if (!sev_enabled || !npt_enabled)

		goto out;



	/* Does the CPU support SEV? */
@@ -1885,6 +1891,7 @@ void __init sev_hardware_setup(void) 
out:

	sev_enabled = sev_supported;

	sev_es_enabled = sev_es_supported;

#endif

}



void sev_hardware_teardown(void)