On Sat, 2023-08-19 at 11:43 +0200, Jo Van Bulck wrote: > 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. > > Link: https://lore.kernel.org/all/a2732938-f3db-a0af-3d68-a18060f66e79@xxxxxxxxxxxxxx/ > Signed-off-by: Jo Van Bulck <jo.vanbulck@xxxxxxxxxxxxxx> > --- > 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 d8587c971..b8f482667 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 b09550cb3..c7bcbc85b 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, Acked-by: Kai Huang <kai.huang@xxxxxxxxx>
