Commit 4daf2a1c authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

x86/sev: Drop redundant and potentially misleading 'sev_enabled' 



Drop the sev_enabled flag and switch its one user over to sev_active().
sev_enabled was made redundant with the introduction of sev_status in
commit b57de6cd ("x86/sev-es: Add SEV-ES Feature Detection").
sev_enabled and sev_active() are guaranteed to be equivalent, as each is
true iff 'sev_status & MSR_AMD64_SEV_ENABLED' is true, and are only ever
written in tandem (ignoring compressed boot's version of sev_status).

Removing sev_enabled avoids confusion over whether it refers to the guest
or the host, and will also allow KVM to usurp "sev_enabled" for its own
purposes.

No functional change intended.

Reviewed-by: default avatarTom 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: <20210422021125.3417167-7-seanjc@google.com>
Acked-by: default avatarBorislav Petkov <bp@suse.de>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 01338078

arch/x86/include/asm/mem_encrypt.h

+0 −1
Original line number Diff line number Diff line
@@ -20,7 +20,6 @@ 


extern u64 sme_me_mask;

extern u64 sev_status;

extern bool sev_enabled;



void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr,

			 unsigned long decrypted_kernel_vaddr,

arch/x86/mm/mem_encrypt.c

+4 −6
Original line number Diff line number Diff line
@@ -44,8 +44,6 @@ EXPORT_SYMBOL(sme_me_mask); 
DEFINE_STATIC_KEY_FALSE(sev_enable_key);

EXPORT_SYMBOL_GPL(sev_enable_key);



bool sev_enabled __section(".data");



/* Buffer used for early in-place encryption by BSP, no locking needed */

static char sme_early_buffer[PAGE_SIZE] __initdata __aligned(PAGE_SIZE);
@@ -373,14 +371,14 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size) 
 * up under SME the trampoline area cannot be encrypted, whereas under SEV

 * the trampoline area must be encrypted.

 */

bool sme_active(void)

bool sev_active(void)

{

	return sme_me_mask && !sev_enabled;

	return sev_status & MSR_AMD64_SEV_ENABLED;

}



bool sev_active(void)

bool sme_active(void)

{

	return sev_status & MSR_AMD64_SEV_ENABLED;

	return sme_me_mask && !sev_active();

}

EXPORT_SYMBOL_GPL(sev_active);

arch/x86/mm/mem_encrypt_identity.c

+0 −1
Original line number Diff line number Diff line
@@ -545,7 +545,6 @@ void __init sme_enable(struct boot_params *bp) 


		/* SEV state cannot be controlled by a command line option */

		sme_me_mask = me_mask;

		sev_enabled = true;

		physical_mask &= ~sme_me_mask;

		return;

	}