diff mbox series

[12/25] x86/sgx: Add helper to update SGX_LEPUBKEYHASHn MSRs

Message ID 6730fbd2f7b26532f09e5a5e416a58f03a66d222.1614590788.git.kai.huang@intel.com (mailing list archive)
State New, archived
Headers show
Series KVM SGX virtualization support | expand

Commit Message

Huang, Kai March 1, 2021, 9:45 a.m. UTC 
Add a helper to update SGX_LEPUBKEYHASHn MSRs.  SGX virtualization also
needs to update those MSRs based on guest's "virtual" SGX_LEPUBKEYHASHn
before EINIT from guest.

Acked-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Kai Huang <kai.huang@intel.com>
---
 arch/x86/kernel/cpu/sgx/ioctl.c |  5 ++---
 arch/x86/kernel/cpu/sgx/main.c  | 15 +++++++++++++++
 arch/x86/kernel/cpu/sgx/sgx.h   |  2 ++
 3 files changed, 19 insertions(+), 3 deletions(-)

Comments

Sean Christopherson March 1, 2021, 4:57 p.m. UTC | #1 
On Mon, Mar 01, 2021, Kai Huang wrote:
> diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
> index 8c922e68274d..276220d0e4b5 100644
> --- a/arch/x86/kernel/cpu/sgx/main.c
> +++ b/arch/x86/kernel/cpu/sgx/main.c
> @@ -696,6 +696,21 @@ static bool __init sgx_page_cache_init(void)
>  	return true;
>  }
>  
> +
> +/*
> + * Update the SGX_LEPUBKEYHASH MSRs to the values specified by caller.
> + * Bare-metal driver requires to update them to hash of enclave's signer
> + * before EINIT. KVM needs to update them to guest's virtual MSR values
> + * before doing EINIT from guest.
> + */
> +void sgx_update_lepubkeyhash(u64 *lepubkeyhash)
> +{
> +	int i;

Probably worth adding:

	WARN_ON_ONCE(preemptible());

> +
> +	for (i = 0; i < 4; i++)
> +		wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + i, lepubkeyhash[i]);
> +}
> +
>  static int __init sgx_init(void)
>  {
>  	int ret;
Huang, Kai March 2, 2021, 12:34 a.m. UTC | #2 
On Mon, 2021-03-01 at 08:57 -0800, Sean Christopherson wrote:
> On Mon, Mar 01, 2021, Kai Huang wrote:
> > diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
> > index 8c922e68274d..276220d0e4b5 100644
> > --- a/arch/x86/kernel/cpu/sgx/main.c
> > +++ b/arch/x86/kernel/cpu/sgx/main.c
> > @@ -696,6 +696,21 @@ static bool __init sgx_page_cache_init(void)
> >  	return true;
> >  }
> >  
> > 
> > 
> > 
> > +
> > +/*
> > + * Update the SGX_LEPUBKEYHASH MSRs to the values specified by caller.
> > + * Bare-metal driver requires to update them to hash of enclave's signer
> > + * before EINIT. KVM needs to update them to guest's virtual MSR values
> > + * before doing EINIT from guest.
> > + */
> > +void sgx_update_lepubkeyhash(u64 *lepubkeyhash)
> > +{
> > +	int i;
> 
> Probably worth adding:
> 
> 	WARN_ON_ONCE(preemptible());

Agreed. Will do.

> 
> > +
> > +	for (i = 0; i < 4; i++)
> > +		wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + i, lepubkeyhash[i]);
> > +}
> > +
> >  static int __init sgx_init(void)
> >  {
> >  	int ret;
diff mbox series

Patch

diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
index e5977752c7be..1bae754268d1 100644
--- a/arch/x86/kernel/cpu/sgx/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -495,7 +495,7 @@  static int sgx_encl_init(struct sgx_encl *encl, struct sgx_sigstruct *sigstruct,
 			 void *token)
 {
 	u64 mrsigner[4];
-	int i, j, k;
+	int i, j;
 	void *addr;
 	int ret;
 
@@ -544,8 +544,7 @@  static int sgx_encl_init(struct sgx_encl *encl, struct sgx_sigstruct *sigstruct,
 
 			preempt_disable();
 
-			for (k = 0; k < 4; k++)
-				wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + k, mrsigner[k]);
+			sgx_update_lepubkeyhash(mrsigner);
 
 			ret = __einit(sigstruct, token, addr);
 
diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index 8c922e68274d..276220d0e4b5 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -696,6 +696,21 @@  static bool __init sgx_page_cache_init(void)
 	return true;
 }
 
+
+/*
+ * Update the SGX_LEPUBKEYHASH MSRs to the values specified by caller.
+ * Bare-metal driver requires to update them to hash of enclave's signer
+ * before EINIT. KVM needs to update them to guest's virtual MSR values
+ * before doing EINIT from guest.
+ */
+void sgx_update_lepubkeyhash(u64 *lepubkeyhash)
+{
+	int i;
+
+	for (i = 0; i < 4; i++)
+		wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + i, lepubkeyhash[i]);
+}
+
 static int __init sgx_init(void)
 {
 	int ret;
diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h
index 5d71c9c8644d..d4b19e5cca16 100644
--- a/arch/x86/kernel/cpu/sgx/sgx.h
+++ b/arch/x86/kernel/cpu/sgx/sgx.h
@@ -92,4 +92,6 @@  static inline int __init sgx_vepc_init(void)
 }
 #endif
 
+void sgx_update_lepubkeyhash(u64 *lepubkeyhash);
+
 #endif /* _X86_SGX_H */