[PATCH 2/2] kselftest/arm64: Correct buffer size for SME ZA storage

From: Zenghui Yu
Date: Sun Dec 18 2022 - 04:30:50 EST


It looks like a copy-paste error to describe the ZA buffer size using (the
number of P registers * the maximum size of a Z register). This doesn't
have practical impact though as we're always allocating enough space even
for the architectural maximum ZA storage, with SVL equals to 2048 bits.

Switch to use ZA_SIG_REGS_SIZE(SVE_VQ_MAX). setup_za() will need to
initialize two 64MB arraies with this change and can be optimized later (if
someone complain).

Signed-off-by: Zenghui Yu <yuzenghui@xxxxxxxxxx>
---
tools/testing/selftests/arm64/abi/syscall-abi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/arm64/abi/syscall-abi.c b/tools/testing/selftests/arm64/abi/syscall-abi.c
index 24a498029c78..4adeb21f500e 100644
--- a/tools/testing/selftests/arm64/abi/syscall-abi.c
+++ b/tools/testing/selftests/arm64/abi/syscall-abi.c
@@ -282,8 +282,8 @@ static int check_svcr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
return errors;
}

-uint8_t za_in[SVE_NUM_PREGS * __SVE_ZREG_SIZE(SVE_VQ_MAX)];
-uint8_t za_out[SVE_NUM_PREGS * __SVE_ZREG_SIZE(SVE_VQ_MAX)];
+uint8_t za_in[ZA_SIG_REGS_SIZE(SVE_VQ_MAX)];
+uint8_t za_out[ZA_SIG_REGS_SIZE(SVE_VQ_MAX)];

static void setup_za(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
uint64_t svcr)
--
2.33.0