| Message ID | bd05c8faee64972a9e01f9497d1870dc267a55f4.1724309198.git.christophe.leroy@csgroup.eu |
|---|---|
| State | New |
| Headers | show |
| Series | Wire up getrandom() vDSO implementation on powerpc | expand |
On Thu, Aug 22, 2024 at 09:13:24AM +0200, Christophe Leroy wrote: > On powerpc, a call to a VDSO function is not a standard C function > call. Unlike x86 that returns a negated error code in case of an > error, powerpc sets CR[SO] and returns the error code as a > positive value. > > So use a macro called VDSO_CALL() which takes a pointer to the > function to call, the number of arguments and the arguments. You'll probably want to move to VDSO_CALL() for the whole test suite, not just the getrandom one, right?
Le 26/08/2024 à 09:37, Jason A. Donenfeld a écrit : > On Thu, Aug 22, 2024 at 09:13:24AM +0200, Christophe Leroy wrote: >> On powerpc, a call to a VDSO function is not a standard C function >> call. Unlike x86 that returns a negated error code in case of an >> error, powerpc sets CR[SO] and returns the error code as a >> positive value. >> >> So use a macro called VDSO_CALL() which takes a pointer to the >> function to call, the number of arguments and the arguments. > > You'll probably want to move to VDSO_CALL() for the whole test suite, > not just the getrandom one, right? Yes indeed, the following needs it as well: vdso_test_abi.c vdso_test_getcpu.c vdso_test_gettimeofday.c vdso_test_correctness.c Christophe
diff --git a/tools/testing/selftests/vDSO/vdso_call.h b/tools/testing/selftests/vDSO/vdso_call.h new file mode 100644 index 000000000000..ca5db2220925 --- /dev/null +++ b/tools/testing/selftests/vDSO/vdso_call.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Macro to call vDSO functions + * + * Copyright (C) 2024 Christophe Leroy <christophe.leroy@csgroup.eu>, CS GROUP France + */ +#ifndef __VDSO_CALL_H__ +#define __VDSO_CALL_H__ + +#define VDSO_CALL(fn, nr, args...) fn(args) + +#endif diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c index 02bcffc23e0c..16ad400721c3 100644 --- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c +++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c @@ -22,6 +22,7 @@ #include "../kselftest.h" #include "parse_vdso.h" #include "vdso_config.h" +#include "vdso_call.h" #ifndef timespecsub #define timespecsub(tsp, usp, vsp) \ @@ -147,7 +148,7 @@ static ssize_t vgetrandom(void *buf, size_t len, unsigned long flags) exit(KSFT_FAIL); } } - return grnd_ctx.fn(buf, len, flags, state, grnd_ctx.params.size_of_opaque_state); + return VDSO_CALL(grnd_ctx.fn, 5, buf, len, flags, state, grnd_ctx.params.size_of_opaque_state); } enum { TRIALS = 25000000, THREADS = 256 };
On powerpc, a call to a VDSO function is not a standard C function call. Unlike x86 that returns a negated error code in case of an error, powerpc sets CR[SO] and returns the error code as a positive value. So use a macro called VDSO_CALL() which takes a pointer to the function to call, the number of arguments and the arguments. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- tools/testing/selftests/vDSO/vdso_call.h | 12 ++++++++++++ tools/testing/selftests/vDSO/vdso_test_getrandom.c | 3 ++- 2 files changed, 14 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/vDSO/vdso_call.h