[PATCH v4 05/13] selftests/sgx: Include memory clobber for inline asm in test enclave

Jo Van Bulck posted 13 patches 2 years, 3 months ago
There is a newer version of this series
[PATCH v4 05/13] selftests/sgx: Include memory clobber for inline asm in test enclave
Posted by Jo Van Bulck 2 years, 3 months ago
Add the "memory" clobber to the EMODPE and EACCEPT asm blocks to tell the
compiler the assembly code accesses to the secinfo struct. This ensures
the compiler treats the asm block as a memory barrier and the write to
secinfo will be visible to ENCLU.

Signed-off-by: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
---
 tools/testing/selftests/sgx/test_encl.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/sgx/test_encl.c b/tools/testing/selftests/sgx/test_encl.c
index 706c1f7260ff..dfe531c5f560 100644
--- a/tools/testing/selftests/sgx/test_encl.c
+++ b/tools/testing/selftests/sgx/test_encl.c
@@ -24,10 +24,11 @@ static void do_encl_emodpe(void *_op)
 	secinfo.flags = op->flags;
 
 	asm volatile(".byte 0x0f, 0x01, 0xd7"
-				:
+				: /* no outputs */
 				: "a" (EMODPE),
 				  "b" (&secinfo),
-				  "c" (op->epc_addr));
+				  "c" (op->epc_addr)
+				: "memory" /* read from secinfo pointer */);
 }
 
 static void do_encl_eaccept(void *_op)
@@ -42,7 +43,8 @@ static void do_encl_eaccept(void *_op)
 				: "=a" (rax)
 				: "a" (EACCEPT),
 				  "b" (&secinfo),
-				  "c" (op->epc_addr));
+				  "c" (op->epc_addr)
+				: "memory" /* read from secinfo pointer */);
 
 	op->ret = rax;
 }
-- 
2.25.1
Re: [PATCH v4 05/13] selftests/sgx: Include memory clobber for inline asm in test enclave
Posted by Huang, Kai 2 years, 3 months ago
On Fri, 2023-08-25 at 15:32 +0200, Jo Van Bulck wrote:
> Add the "memory" clobber to the EMODPE and EACCEPT asm blocks to tell the
> compiler the assembly code accesses to the secinfo struct. This ensures
> the compiler treats the asm block as a memory barrier and the write to
> secinfo will be visible to ENCLU.
> 
> Signed-off-by: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
> Reviewed-by: Kai Huang <kai.huang@intel.com>
> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
> ---
>  tools/testing/selftests/sgx/test_encl.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/testing/selftests/sgx/test_encl.c b/tools/testing/selftests/sgx/test_encl.c
> index 706c1f7260ff..dfe531c5f560 100644
> --- a/tools/testing/selftests/sgx/test_encl.c
> +++ b/tools/testing/selftests/sgx/test_encl.c
> @@ -24,10 +24,11 @@ static void do_encl_emodpe(void *_op)
>  	secinfo.flags = op->flags;
>  
>  	asm volatile(".byte 0x0f, 0x01, 0xd7"
> -				:
> +				: /* no outputs */
>  				: "a" (EMODPE),
>  				  "b" (&secinfo),
> -				  "c" (op->epc_addr));
> +				  "c" (op->epc_addr)
> +				: "memory" /* read from secinfo pointer */);
>  }
>  
>  static void do_encl_eaccept(void *_op)
> @@ -42,7 +43,8 @@ static void do_encl_eaccept(void *_op)
>  				: "=a" (rax)
>  				: "a" (EACCEPT),
>  				  "b" (&secinfo),
> -				  "c" (op->epc_addr));
> +				  "c" (op->epc_addr)
> +				: "memory" /* read from secinfo pointer */);
>  
>  	op->ret = rax;
>  }

To me this is also a bug fix patch, thus as Jarkko said should be ahead of other
non-bug fix patches.

And also include the Fixes tag?
Re: [PATCH v4 05/13] selftests/sgx: Include memory clobber for inline asm in test enclave
Posted by Jo Van Bulck 2 years, 3 months ago
On 29.08.23 13:07, Huang, Kai wrote:> To me this is also a bug fix 
patch, thus as Jarkko said should be ahead of other
> non-bug fix patches.
> 
> And also include the Fixes tag?

Thanks, moving this ahead and including the tag Fixes: 20404a808593 
("selftests/sgx: Add test for EPCM permission changes")

Best,
Jo