Add two tests to check vector save/restore when a signal is received during a vector routine. One test ensures that a value is not clobbered during signal handling. The other verifies that vector registers modified in the signal handler are properly reflected when the signal handling is complete.
Signed-off-by: Charlie Jenkins charlie@rivosinc.com --- These tests came about to highlight the bug fixed in https://lore.kernel.org/lkml/20240403072638.567446-1-bjorn@kernel.org/ and will only pass with that fix applied. --- tools/testing/selftests/riscv/Makefile | 2 +- tools/testing/selftests/riscv/sigreturn/.gitignore | 1 + tools/testing/selftests/riscv/sigreturn/Makefile | 12 ++++ .../testing/selftests/riscv/sigreturn/sigreturn.c | 82 ++++++++++++++++++++++ 4 files changed, 96 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/riscv/Makefile b/tools/testing/selftests/riscv/Makefile index 4a9ff515a3a0..7ce03d832b64 100644 --- a/tools/testing/selftests/riscv/Makefile +++ b/tools/testing/selftests/riscv/Makefile @@ -5,7 +5,7 @@ ARCH ?= $(shell uname -m 2>/dev/null || echo not)
ifneq (,$(filter $(ARCH),riscv)) -RISCV_SUBTARGETS ?= hwprobe vector mm +RISCV_SUBTARGETS ?= hwprobe vector mm sigreturn else RISCV_SUBTARGETS := endif diff --git a/tools/testing/selftests/riscv/sigreturn/.gitignore b/tools/testing/selftests/riscv/sigreturn/.gitignore new file mode 100644 index 000000000000..35002b8ae780 --- /dev/null +++ b/tools/testing/selftests/riscv/sigreturn/.gitignore @@ -0,0 +1 @@ +sigreturn diff --git a/tools/testing/selftests/riscv/sigreturn/Makefile b/tools/testing/selftests/riscv/sigreturn/Makefile new file mode 100644 index 000000000000..eb8bac9279a8 --- /dev/null +++ b/tools/testing/selftests/riscv/sigreturn/Makefile @@ -0,0 +1,12 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2021 ARM Limited +# Originally tools/testing/arm64/abi/Makefile + +CFLAGS += -I$(top_srcdir)/tools/include + +TEST_GEN_PROGS := sigreturn + +include ../../lib.mk + +$(OUTPUT)/sigreturn: sigreturn.c + $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ diff --git a/tools/testing/selftests/riscv/sigreturn/sigreturn.c b/tools/testing/selftests/riscv/sigreturn/sigreturn.c new file mode 100644 index 000000000000..62397d5934f1 --- /dev/null +++ b/tools/testing/selftests/riscv/sigreturn/sigreturn.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <ucontext.h> +#include <linux/ptrace.h> +#include "../../kselftest_harness.h" + +#define RISCV_V_MAGIC 0x53465457 +#define DEFAULT_VALUE 2 +#define SIGNAL_HANDLER_OVERRIDE 3 + +static void simple_handle(int sig_no, siginfo_t *info, void *vcontext) +{ + ucontext_t *context = vcontext; + + context->uc_mcontext.__gregs[REG_PC] = context->uc_mcontext.__gregs[REG_PC] + 4; +} + +static void vector_override(int sig_no, siginfo_t *info, void *vcontext) +{ + ucontext_t *context = vcontext; + + // vector state + struct __riscv_extra_ext_header *ext; + struct __riscv_v_ext_state *v_ext_state; + + /* Find the vector context. */ + ext = (void *)(&context->uc_mcontext.__fpregs); + if (ext->hdr.magic != RISCV_V_MAGIC) { + fprintf(stderr, "bad vector magic: %x\n", ext->hdr.magic); + abort(); + } + + v_ext_state = (void *)((char *)(ext) + sizeof(*ext)); + + *(int *)v_ext_state->datap = SIGNAL_HANDLER_OVERRIDE; + + context->uc_mcontext.__gregs[REG_PC] = context->uc_mcontext.__gregs[REG_PC] + 4; +} + +static int vector_sigreturn(int data, void (*handler)(int, siginfo_t *, void *)) +{ + int after_sigreturn; + struct sigaction sig_action = { + .sa_sigaction = handler, + .sa_flags = SA_SIGINFO + }; + + sigaction(SIGSEGV, &sig_action, 0); + + asm(".option push \n\ + .option arch, +v \n\ + vsetivli x0, 1, e32, ta, ma \n\ + vmv.s.x v0, %1 \n\ + # Generate SIGSEGV \n\ + lw a0, 0(x0) \n\ + vmv.x.s %0, v0 \n\ + .option pop" : "=r" (after_sigreturn) : "r" (data)); + + return after_sigreturn; +} + +TEST(vector_restore) +{ + int result; + + result = vector_sigreturn(DEFAULT_VALUE, &simple_handle); + + EXPECT_EQ(DEFAULT_VALUE, result); +} + +TEST(vector_restore_signal_handler_override) +{ + int result; + + result = vector_sigreturn(DEFAULT_VALUE, &vector_override); + + EXPECT_EQ(SIGNAL_HANDLER_OVERRIDE, result); +} + +TEST_HARNESS_MAIN
--- base-commit: 4cece764965020c22cff7665b18a012006359095 change-id: 20240403-vector_sigreturn_tests-8118f0ac54fa