From a4c39ef4ed43103caef80029cd30427a9ff342d8 Mon Sep 17 00:00:00 2001 From: Jo Van Bulck Date: Thu, 5 Oct 2023 17:38:51 +0200 Subject: [PATCH] selftests/sgx: Ensure test enclave buffer is entirely preserved Attach the "used" attribute to instruct the compiler to preserve the static encl_buffer, even if it appears it is not entirely referenced in the enclave code, as expected by the external tests manipulating page permissions. Signed-off-by: Jo Van Bulck Signed-off-by: Dave Hansen Reviewed-by: Jarkko Sakkinen Acked-by: Kai Huang Link: https://lore.kernel.org/all/a2732938-f3db-a0af-3d68-a18060f66e79@cs.kuleuven.be/ Link: https://lore.kernel.org/all/20231005153854.25566-11-jo.vanbulck%40cs.kuleuven.be --- tools/testing/selftests/sgx/defines.h | 1 + tools/testing/selftests/sgx/test_encl.c | 9 +++++---- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/sgx/defines.h b/tools/testing/selftests/sgx/defines.h index d8587c971941a..b8f482667ce14 100644 --- a/tools/testing/selftests/sgx/defines.h +++ b/tools/testing/selftests/sgx/defines.h @@ -13,6 +13,7 @@ #define __aligned(x) __attribute__((__aligned__(x))) #define __packed __attribute__((packed)) +#define __used __attribute__((used)) #include "../../../../arch/x86/include/asm/sgx.h" #include "../../../../arch/x86/include/asm/enclu.h" diff --git a/tools/testing/selftests/sgx/test_encl.c b/tools/testing/selftests/sgx/test_encl.c index 649604c526e77..7465f121fb746 100644 --- a/tools/testing/selftests/sgx/test_encl.c +++ b/tools/testing/selftests/sgx/test_encl.c @@ -5,11 +5,12 @@ #include "defines.h" /* - * Data buffer spanning two pages that will be placed first in .data - * segment. Even if not used internally the second page is needed by - * external test manipulating page permissions. + * Data buffer spanning two pages that will be placed first in the .data + * segment. Even if not used internally the second page is needed by external + * test manipulating page permissions, so mark encl_buffer as "used" to make + * sure it is entirely preserved by the compiler. */ -static uint8_t encl_buffer[8192] = { 1 }; +static uint8_t __used encl_buffer[8192] = { 1 }; enum sgx_enclu_function { EACCEPT = 0x5, -- 2.39.5