From 2679f63fe5e4bb1459a0c20859a99c70c15d5ea1 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Fri, 3 Aug 2018 20:13:05 +1000 Subject: [PATCH] selftests/powerpc/64: Test exception cases in copy_tofrom_user This adds a set of test cases to test the behaviour of copy_tofrom_user when exceptions are encountered accessing the source or destination. Currently, copy_tofrom_user does not always copy as many bytes as possible when an exception occurs on a store to the destination, and that is reflected in failures in these tests. Based on a test program from Anton Blanchard. [paulus@ozlabs.org - test all three paths, wrote commit description, made EX_TABLE create an exception table.] Signed-off-by: Paul Mackerras Signed-off-by: Michael Ellerman --- .../selftests/powerpc/copyloops/.gitignore | 3 + .../selftests/powerpc/copyloops/Makefile | 12 +- .../selftests/powerpc/copyloops/asm/ppc_asm.h | 27 ++-- .../copyloops/copy_tofrom_user_reference.S | 24 ++++ .../powerpc/copyloops/exc_validate.c | 124 ++++++++++++++++++ .../selftests/powerpc/copyloops/stubs.S | 19 +++ 6 files changed, 188 insertions(+), 21 deletions(-) create mode 100644 tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S create mode 100644 tools/testing/selftests/powerpc/copyloops/exc_validate.c create mode 100644 tools/testing/selftests/powerpc/copyloops/stubs.S diff --git a/tools/testing/selftests/powerpc/copyloops/.gitignore b/tools/testing/selftests/powerpc/copyloops/.gitignore index bc6c4ba153af..ce12cd0e2967 100644 --- a/tools/testing/selftests/powerpc/copyloops/.gitignore +++ b/tools/testing/selftests/powerpc/copyloops/.gitignore @@ -8,3 +8,6 @@ memcpy_64_t1 memcpy_64_t2 memcpy_power7_t0 memcpy_power7_t1 +copyuser_64_exc_t0 +copyuser_64_exc_t1 +copyuser_64_exc_t2 diff --git a/tools/testing/selftests/powerpc/copyloops/Makefile b/tools/testing/selftests/powerpc/copyloops/Makefile index 498d8d875ab8..1cf89a34d97c 100644 --- a/tools/testing/selftests/powerpc/copyloops/Makefile +++ b/tools/testing/selftests/powerpc/copyloops/Makefile @@ -12,9 +12,10 @@ ASFLAGS = $(CFLAGS) -Wa,-mpower4 TEST_GEN_PROGS := copyuser_64_t0 copyuser_64_t1 copyuser_64_t2 \ copyuser_p7_t0 copyuser_p7_t1 \ memcpy_64_t0 memcpy_64_t1 memcpy_64_t2 \ - memcpy_p7_t0 memcpy_p7_t1 + memcpy_p7_t0 memcpy_p7_t1 \ + copyuser_64_exc_t0 copyuser_64_exc_t1 copyuser_64_exc_t2 -EXTRA_SOURCES := validate.c ../harness.c +EXTRA_SOURCES := validate.c ../harness.c stubs.S include ../../lib.mk @@ -42,3 +43,10 @@ $(OUTPUT)/memcpy_p7_t%: memcpy_power7.S $(EXTRA_SOURCES) -D COPY_LOOP=test_memcpy_power7 \ -D SELFTEST_CASE=$(subst memcpy_p7_t,,$(notdir $@)) \ -o $@ $^ + +$(OUTPUT)/copyuser_64_exc_t%: copyuser_64.S exc_validate.c ../harness.c \ + copy_tofrom_user_reference.S stubs.S + $(CC) $(CPPFLAGS) $(CFLAGS) \ + -D COPY_LOOP=test___copy_tofrom_user_base \ + -D SELFTEST_CASE=$(subst copyuser_64_exc_t,,$(notdir $@)) \ + -o $@ $^ diff --git a/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h b/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h index 91bc40392eb3..0605df807593 100644 --- a/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h +++ b/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h @@ -1,4 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __SELFTESTS_POWERPC_PPC_ASM_H +#define __SELFTESTS_POWERPC_PPC_ASM_H #include #define CONFIG_ALTIVEC @@ -26,25 +28,10 @@ #define PPC_MTOCRF(A, B) mtocrf A, B -#define EX_TABLE(x, y) - -FUNC_START(enter_vmx_usercopy) - li r3,1 - blr - -FUNC_START(exit_vmx_usercopy) - li r3,0 - blr - -FUNC_START(enter_vmx_ops) - li r3,1 - blr - -FUNC_START(exit_vmx_ops) - blr - -FUNC_START(__copy_tofrom_user_base) - blr +#define EX_TABLE(x, y) \ + .section __ex_table,"a"; \ + .8byte x, y; \ + .previous #define BEGIN_FTR_SECTION .if test_feature #define FTR_SECTION_ELSE .else @@ -56,3 +43,5 @@ FUNC_START(__copy_tofrom_user_base) /* Default to taking the first of any alternative feature sections */ test_feature = 1 + +#endif /* __SELFTESTS_POWERPC_PPC_ASM_H */ diff --git a/tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S b/tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S new file mode 100644 index 000000000000..3363b86407d6 --- /dev/null +++ b/tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S @@ -0,0 +1,24 @@ +#include + +_GLOBAL(copy_tofrom_user_reference) + cmpdi r5,0 + beq 4f + + mtctr r5 + +1: lbz r6,0(r4) +2: stb r6,0(r3) + addi r3,r3,1 + addi r4,r4,1 + bdnz 1b + +3: mfctr r3 + blr + +4: mr r3,r5 + blr + +.section __ex_table,"a" + .llong 1b,3b + .llong 2b,3b +.text diff --git a/tools/testing/selftests/powerpc/copyloops/exc_validate.c b/tools/testing/selftests/powerpc/copyloops/exc_validate.c new file mode 100644 index 000000000000..c896ea9a763c --- /dev/null +++ b/tools/testing/selftests/powerpc/copyloops/exc_validate.c @@ -0,0 +1,124 @@ +#include +#include +#include +#include +#include +#include + +#include "utils.h" + +extern char __start___ex_table[]; +extern char __stop___ex_table[]; + +#if defined(__powerpc64__) +#define UCONTEXT_NIA(UC) (UC)->uc_mcontext.gp_regs[PT_NIP] +#elif defined(__powerpc__) +#define UCONTEXT_NIA(UC) (UC)->uc_mcontext.uc_regs->gregs[PT_NIP] +#else +#error implement UCONTEXT_NIA +#endif + +static void segv_handler(int signr, siginfo_t *info, void *ptr) +{ + ucontext_t *uc = (ucontext_t *)ptr; + unsigned long addr = (unsigned long)info->si_addr; + unsigned long *ip = &UCONTEXT_NIA(uc); + unsigned long *ex_p = (unsigned long *)__start___ex_table; + + while (ex_p < (unsigned long *)__stop___ex_table) { + unsigned long insn, fixup; + + insn = *ex_p++; + fixup = *ex_p++; + + if (insn == *ip) { + *ip = fixup; + return; + } + } + + printf("No exception table match for NIA %lx ADDR %lx\n", *ip, addr); + abort(); +} + +static void setup_segv_handler(void) +{ + struct sigaction action; + + memset(&action, 0, sizeof(action)); + action.sa_sigaction = segv_handler; + action.sa_flags = SA_SIGINFO; + sigaction(SIGSEGV, &action, NULL); +} + +unsigned long COPY_LOOP(void *to, const void *from, unsigned long size); +unsigned long test_copy_tofrom_user_reference(void *to, const void *from, unsigned long size); + +static int total_passed; +static int total_failed; + +static void do_one_test(char *dstp, char *srcp, unsigned long len) +{ + unsigned long got, expected; + + got = COPY_LOOP(dstp, srcp, len); + expected = test_copy_tofrom_user_reference(dstp, srcp, len); + + if (got != expected) { + total_failed++; + printf("FAIL from=%p to=%p len=%ld returned %ld, expected %ld\n", + srcp, dstp, len, got, expected); + //abort(); + } else + total_passed++; +} + +//#define MAX_LEN 512 +#define MAX_LEN 16 + +int test_copy_exception(void) +{ + int page_size; + static char *p, *q; + unsigned long src, dst, len; + + page_size = getpagesize(); + p = mmap(NULL, page_size * 2, PROT_READ|PROT_WRITE, + MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); + + if (p == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + memset(p, 0, page_size); + + setup_segv_handler(); + + if (mprotect(p + page_size, page_size, PROT_NONE)) { + perror("mprotect"); + exit(1); + } + + q = p + page_size - MAX_LEN; + + for (src = 0; src < MAX_LEN; src++) { + for (dst = 0; dst < MAX_LEN; dst++) { + for (len = 0; len < MAX_LEN+1; len++) { + // printf("from=%p to=%p len=%ld\n", q+dst, q+src, len); + do_one_test(q+dst, q+src, len); + } + } + } + + printf("Totals:\n"); + printf(" Pass: %d\n", total_passed); + printf(" Fail: %d\n", total_failed); + + return 0; +} + +int main(void) +{ + return test_harness(test_copy_exception, str(COPY_LOOP)); +} diff --git a/tools/testing/selftests/powerpc/copyloops/stubs.S b/tools/testing/selftests/powerpc/copyloops/stubs.S new file mode 100644 index 000000000000..ec8bcf2bf1c2 --- /dev/null +++ b/tools/testing/selftests/powerpc/copyloops/stubs.S @@ -0,0 +1,19 @@ +#include + +FUNC_START(enter_vmx_usercopy) + li r3,1 + blr + +FUNC_START(exit_vmx_usercopy) + li r3,0 + blr + +FUNC_START(enter_vmx_ops) + li r3,1 + blr + +FUNC_START(exit_vmx_ops) + blr + +FUNC_START(__copy_tofrom_user_base) + blr -- 2.30.2