Philippe Mathieu-Daudé <phi...@redhat.com> writes:
> On 3/16/20 6:21 PM, Alex Bennée wrote: >> This tests a bunch of registers that the kernel allows userspace to >> read including the CPUID registers. We need a SVE aware compiler as we >> are testing the id_aa64zfr0_el1 register in the set. >> Signed-off-by: Alex Bennée <alex.ben...@linaro.org> >> Reviewed-by: Richard Henderson <richard.hender...@linaro.org> >> Message-Id: <20190205190224.2198-7-alex.ben...@linaro.org> >> --- >> vgdbstub >> - don't build unless using docker or CROSS_CC_HAS_SVE >> --- >> tests/tcg/aarch64/sysregs.c | 172 ++++++++++++++++++++++++++++++ >> tests/tcg/aarch64/Makefile.target | 6 ++ >> 2 files changed, 178 insertions(+) >> create mode 100644 tests/tcg/aarch64/sysregs.c >> diff --git a/tests/tcg/aarch64/sysregs.c >> b/tests/tcg/aarch64/sysregs.c >> new file mode 100644 >> index 00000000000..40cf8d2877e >> --- /dev/null >> +++ b/tests/tcg/aarch64/sysregs.c >> @@ -0,0 +1,172 @@ >> +/* >> + * Check emulated system register access for linux-user mode. >> + * >> + * See: >> https://www.kernel.org/doc/Documentation/arm64/cpu-feature-registers.txt >> + * >> + * Copyright (c) 2019 Linaro >> + * >> + * This work is licensed under the terms of the GNU GPL, version 2 or later. >> + * See the COPYING file in the top-level directory. >> + * >> + * SPDX-License-Identifier: GPL-2.0-or-later >> + */ >> + >> +#include <asm/hwcap.h> >> +#include <stdio.h> >> +#include <sys/auxv.h> >> +#include <signal.h> >> +#include <string.h> >> +#include <stdbool.h> >> + >> +#ifndef HWCAP_CPUID >> +#define HWCAP_CPUID (1 << 11) >> +#endif >> + >> +int failed_bit_count; >> + >> +/* Read and print system register `id' value */ >> +#define get_cpu_reg(id) ({ \ >> + unsigned long __val = 0xdeadbeef; \ >> + asm("mrs %0, "#id : "=r" (__val)); \ >> + printf("%-20s: 0x%016lx\n", #id, __val); \ >> + __val; \ >> + }) >> + >> +/* As above but also check no bits outside of `mask' are set*/ >> +#define get_cpu_reg_check_mask(id, mask) ({ \ >> + unsigned long __cval = get_cpu_reg(id); \ >> + unsigned long __extra = __cval & ~mask; \ >> + if (__extra) { \ >> + printf("%-20s: 0x%016lx\n", " !!extra bits!!", __extra); >> \ >> + failed_bit_count++; \ >> + } \ >> +}) >> + >> +/* As above but check RAZ */ >> +#define get_cpu_reg_check_zero(id) ({ \ >> + unsigned long __val = 0xdeadbeef; \ >> + asm("mrs %0, "#id : "=r" (__val)); \ >> + if (__val) { \ >> + printf("%-20s: 0x%016lx (not RAZ!)\n", #id, __val); \ >> + failed_bit_count++; \ >> + } \ >> +}) >> + >> +/* Chunk up mask into 63:48, 47:32, 31:16, 15:0 to ease counting */ >> +#define _m(a, b, c, d) (0x ## a ## b ## c ## d ##ULL) >> + >> +bool should_fail; >> +int should_fail_count; >> +int should_not_fail_count; >> +uintptr_t failed_pc[10]; >> + >> +void sigill_handler(int signo, siginfo_t *si, void *data) >> +{ >> + ucontext_t *uc = (ucontext_t *)data; >> + >> + if (should_fail) { >> + should_fail_count++; >> + } else { >> + uintptr_t pc = (uintptr_t) uc->uc_mcontext.pc; >> + failed_pc[should_not_fail_count++] = pc; >> + } >> + uc->uc_mcontext.pc += 4; >> +} >> + >> +int main(void) >> +{ >> + struct sigaction sa; >> + >> + /* Hook in a SIGILL handler */ >> + memset(&sa, 0, sizeof(struct sigaction)); >> + sa.sa_flags = SA_SIGINFO; >> + sa.sa_sigaction = &sigill_handler; >> + sigemptyset(&sa.sa_mask); >> + >> + if (sigaction(SIGILL, &sa, 0) != 0) { >> + perror("sigaction"); >> + return 1; >> + } >> + >> + /* Counter values have been exposed since Linux 4.12 */ >> + printf("Checking Counter registers\n"); >> + >> + get_cpu_reg(ctr_el0); >> + get_cpu_reg(cntvct_el0); >> + get_cpu_reg(cntfrq_el0); >> + >> + /* HWCAP_CPUID indicates we can read feature registers, since Linux >> 4.11 */ >> + if (!(getauxval(AT_HWCAP) & HWCAP_CPUID)) { >> + printf("CPUID registers unavailable\n"); >> + return 1; >> + } else { >> + printf("Checking CPUID registers\n"); >> + } >> + >> + /* >> + * Some registers only expose some bits to user-space. Anything >> + * that is IMPDEF is exported as 0 to user-space. The _mask checks >> + * assert no extra bits are set. >> + * >> + * This check is *not* comprehensive as some fields are set to >> + * minimum valid fields - for the purposes of this check allowed >> + * to have non-zero values. >> + */ >> + get_cpu_reg_check_mask(id_aa64isar0_el1, _m(00ff,ffff,f0ff,fff0)); >> + get_cpu_reg_check_mask(id_aa64isar1_el1, _m(0000,00f0,ffff,ffff)); >> + /* TGran4 & TGran64 as pegged to -1 */ >> + get_cpu_reg_check_mask(id_aa64mmfr0_el1, _m(0000,0000,ff00,0000)); >> + get_cpu_reg_check_zero(id_aa64mmfr1_el1); >> + /* EL1/EL0 reported as AA64 only */ >> + get_cpu_reg_check_mask(id_aa64pfr0_el1, _m(000f,000f,00ff,0011)); >> + get_cpu_reg_check_mask(id_aa64pfr1_el1, _m(0000,0000,0000,00f0)); >> + /* all hidden, DebugVer fixed to 0x6 (ARMv8 debug architecture) */ >> + get_cpu_reg_check_mask(id_aa64dfr0_el1, _m(0000,0000,0000,0006)); >> + get_cpu_reg_check_zero(id_aa64dfr1_el1); >> + get_cpu_reg_check_zero(id_aa64zfr0_el1); >> + >> + get_cpu_reg_check_zero(id_aa64afr0_el1); >> + get_cpu_reg_check_zero(id_aa64afr1_el1); >> + >> + get_cpu_reg_check_mask(midr_el1, _m(0000,0000,ffff,ffff)); >> + /* mpidr sets bit 31, everything else hidden */ >> + get_cpu_reg_check_mask(mpidr_el1, _m(0000,0000,8000,0000)); >> + /* REVIDR is all IMPDEF so should be all zeros to user-space */ >> + get_cpu_reg_check_zero(revidr_el1); >> + >> + /* >> + * There are a block of more registers that are RAZ in the rest of >> + * the Op0=3, Op1=0, CRn=0, CRm=0,4,5,6,7 space. However for >> + * brevity we don't check stuff that is currently un-allocated >> + * here. Feel free to add them ;-) >> + */ >> + >> + printf("Remaining registers should fail\n"); >> + should_fail = true; >> + >> + /* Unexposed register access causes SIGILL */ >> + get_cpu_reg(id_mmfr0_el1); >> + get_cpu_reg(id_mmfr1_el1); >> + get_cpu_reg(id_mmfr2_el1); >> + get_cpu_reg(id_mmfr3_el1); >> + >> + get_cpu_reg(mvfr0_el1); >> + get_cpu_reg(mvfr1_el1); >> + >> + if (should_not_fail_count > 0) { >> + int i; >> + for (i = 0; i < should_not_fail_count; i++) { >> + uintptr_t pc = failed_pc[i]; >> + uint32_t insn = *(uint32_t *) pc; >> + printf("insn %#x @ %#lx unexpected FAIL\n", insn, pc); >> + } >> + return 1; >> + } >> + >> + if (failed_bit_count > 0) { >> + printf("Extra information leaked to user-space!\n"); >> + return 1; >> + } >> + >> + return should_fail_count == 6 ? 0 : 1; >> +} >> diff --git a/tests/tcg/aarch64/Makefile.target >> b/tests/tcg/aarch64/Makefile.target >> index 8ed477d0d51..a25afc071cc 100644 >> --- a/tests/tcg/aarch64/Makefile.target >> +++ b/tests/tcg/aarch64/Makefile.target >> @@ -42,4 +42,10 @@ run-semiconsole: semiconsole >> run-plugin-semiconsole-with-%: >> $(call skip-test, $<, "MANUAL ONLY") >> +ifneq ($(DOCKER_IMAGE)$(CROSS_CC_HAS_SVE),) >> +# System Registers Tests >> +AARCH64_TESTS += sysregs >> +sysregs: CFLAGS+=-march=armv8.1-a+sve >> +endif >> + >> TESTS += $(AARCH64_TESTS) >> > > warning: while parsing target description (at line 47): Vector > "vq128hf" references undefined type "ieee_half" > warning: Could not load XML target description; ignoring > *** stack smashing detected ***: <unknown> terminated How? That test doesn't even use the gdbstub. > > (GCC 9.2.1, Fedora 30) -- Alex Bennée