From nobody Sat Nov 1 14:14:01 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 25FE43002DC; Wed, 15 Oct 2025 18:34:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760553247; cv=none; b=KghF6hzIYH5Ot4ZU6YfNB7P2i87yj+NozOJx9DPjarpdHAz4mObgpoGzEWuDpK39KqHwuhQQjsYOTF3aoEm51R7cQvrrFXVeiYKsMQhc8ciD5F0LkRtHKdV9pn/3lH4lAm0LRxvE4doxfog4wsyGzu5zWPuAA0k0m5VAHKUllKI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760553247; c=relaxed/simple; bh=Xv6yHCpNjzsH8/JCHYEyM4n96nFPTL8HY23YJ+yYWPM=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=KWqkHHu3nOq0nXgZ6qxInNVPciDdB0bjA2U/XiFkAOf+/sKFJqhI32+r7Gyr8lA3BY9UsBtJFXaEyRvP/VlQbi4nnqo/XBuWgGVy0UYhnYcUmYAhG6RyXainCkq9GTSZE208Vfm9v3TFdQWOLSP2g3wSN3HZCkxEs/kHZJYVgc4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VHP4U2l5; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VHP4U2l5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC578C116B1; Wed, 15 Oct 2025 18:34:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760553246; bh=Xv6yHCpNjzsH8/JCHYEyM4n96nFPTL8HY23YJ+yYWPM=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=VHP4U2l5loyGV8ALU7Ia2R6/40D6LmhS6xILEBqjXewj3GySfW0t1tVXzNP61zHVW sXHbk88fLJrMna5/0AwBTIvnRdO7Sm9Ae6SDtj9lh+8R4cgvRUaTRUXNXaqxt6JtxZ +skunpbXlJNBkTcvH6TcYAOXjYQD93rvadMk46aZHznN5HGSWxotRtv0qsTpkBXU39 PKZqSN/kDgG+IvDZDblSuRgkv5gQiyfLxaMG18eH7/sb0gEb9h82JY56PbMRdy7cc2 KHvc06/ic1N9xypP/ENWi9sRiGgAQDddwoInJjW2lRx/QXc+uclV2v0g174eZBsWAX zP/N0kMhDV36w== From: Mark Brown Date: Wed, 15 Oct 2025 18:56:37 +0100 Subject: [PATCH v2 2/3] kselftst/arm64: Test NT_ARM_SVE FPSIMD format writes on non-SVE systems Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20251015-arm64-sme-ptrace-sme-only-v2-2-33c7b2f27cbf@kernel.org> References: <20251015-arm64-sme-ptrace-sme-only-v2-0-33c7b2f27cbf@kernel.org> In-Reply-To: <20251015-arm64-sme-ptrace-sme-only-v2-0-33c7b2f27cbf@kernel.org> To: Catalin Marinas , Will Deacon , Shuah Khan , Jonathan Corbet , Oleg Nesterov Cc: Mark Rutland , David Spickett , Thiago Jung Bauermann , Luis Machado , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Mark Brown X-Mailer: b4 0.15-dev-2a268 X-Developer-Signature: v=1; a=openpgp-sha256; l=2876; i=broonie@kernel.org; h=from:subject:message-id; bh=Xv6yHCpNjzsH8/JCHYEyM4n96nFPTL8HY23YJ+yYWPM=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBo7+kTtExQl2fALYDooDYk+IBi3sFFozHENC+hJ 2suVYsiBFGJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCaO/pEwAKCRAk1otyXVSH 0BOvB/98hVKg3ztxRIYwgaH9DWjipCXQnv+FYob/1LS82o5N10ru8M1jnZVp9eHnHhMoSYCxDmz aMhbTxD1AOQKxn4FqpEuwTv1hiC+5++THVw11uZZDcqrtzbCsxT6a0TZD7YuiNupitSSuI1mnUS 6k6U8qNWOIIdjIBJYCZasj5TRCZhgkw7nzVD4gKDSZ9jvefU9fIdNsQMCsR5mh2LZVT7pE7Hn7d R7Wv8vG+xA6VcqUTK/6Ra10mIHNzQE7Vg74wHvRzd4xj7n7qNDf+dfMa3vShssHdNCtpTmmG8ow ybRqI/4CpbvjZthTLw/L7XCxGGddlgnVwkm8aeTNVfrL0SW7 X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB In order to allow exiting streaming mode on systems with SME but not SVE we allow writes of FPSIMD format data via NT_ARM_SVE even when SVE is not supported, add a test case that covers this to sve-ptrace. We do not support reads. Signed-off-by: Mark Brown --- tools/testing/selftests/arm64/fp/sve-ptrace.c | 61 +++++++++++++++++++++++= ++++ 1 file changed, 61 insertions(+) diff --git a/tools/testing/selftests/arm64/fp/sve-ptrace.c b/tools/testing/= selftests/arm64/fp/sve-ptrace.c index e0fc3a001e28..f44d44618575 100644 --- a/tools/testing/selftests/arm64/fp/sve-ptrace.c +++ b/tools/testing/selftests/arm64/fp/sve-ptrace.c @@ -394,6 +394,58 @@ static void ptrace_sve_fpsimd(pid_t child, const struc= t vec_type *type) free(svebuf); } =20 +/* Write the FPSIMD registers via the SVE regset when SVE is not supported= */ +static void ptrace_sve_fpsimd_no_sve(pid_t child) +{ + void *svebuf; + struct user_sve_header *sve; + struct user_fpsimd_state *fpsimd, new_fpsimd; + unsigned int i, j; + unsigned char *p; + int ret; + + svebuf =3D malloc(SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD)); + if (!svebuf) { + ksft_test_result_fail("Failed to allocate FPSIMD buffer\n"); + return; + } + + /* On a system without SVE the VL should be set to 0 */ + memset(svebuf, 0, SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD)); + sve =3D svebuf; + sve->flags =3D SVE_PT_REGS_FPSIMD; + sve->size =3D SVE_PT_SIZE(0, SVE_PT_REGS_FPSIMD); + sve->vl =3D 0; + + /* Try to set a known FPSIMD state via PT_REGS_SVE */ + fpsimd =3D (struct user_fpsimd_state *)((char *)sve + + SVE_PT_FPSIMD_OFFSET); + for (i =3D 0; i < 32; ++i) { + p =3D (unsigned char *)&fpsimd->vregs[i]; + + for (j =3D 0; j < sizeof(fpsimd->vregs[i]); ++j) + p[j] =3D j; + } + + ret =3D set_sve(child, &vec_types[0], sve); + ksft_test_result(ret =3D=3D 0, "FPSIMD write via SVE\n"); + if (ret) { + ksft_test_result_skip("Verify FPSIMD write via SVE\n"); + goto out; + } + + /* Verify via the FPSIMD regset */ + if (get_fpsimd(child, &new_fpsimd)) { + ksft_test_result_skip("Verify FPSIMD write via SVE\n"); + goto out; + } + ksft_test_result(memcmp(fpsimd, &new_fpsimd, sizeof(*fpsimd)) =3D=3D 0, + "Verify FPSIMD write via SVE\n"); + +out: + free(svebuf); +} + /* Validate attempting to set SVE data and read SVE data */ static void ptrace_set_sve_get_sve_data(pid_t child, const struct vec_type *type, @@ -826,6 +878,15 @@ static int do_parent(pid_t child) } } =20 + /* We support SVE writes of FPSMID format on SME only systems */ + if (!(getauxval(AT_HWCAP) & HWCAP_SVE) && + (getauxval(AT_HWCAP2) & HWCAP2_SME)) { + ptrace_sve_fpsimd_no_sve(child); + } else { + ksft_test_result_skip("FPSIMD write via SVE\n"); + ksft_test_result_skip("Verify FPSIMD write via SVE\n"); + } + ret =3D EXIT_SUCCESS; =20 error: --=20 2.47.2