diff options
| -rw-r--r-- | tools/testing/selftests/powerpc/tm/.gitignore | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/tm/Makefile | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/tm/tm-signal-stack.c | 76 |
3 files changed, 78 insertions, 1 deletions
diff --git a/tools/testing/selftests/powerpc/tm/.gitignore b/tools/testing/selftests/powerpc/tm/.gitignore index 61c318fdace4..e6668217ccd0 100644 --- a/tools/testing/selftests/powerpc/tm/.gitignore +++ b/tools/testing/selftests/powerpc/tm/.gitignore @@ -1,3 +1,4 @@ tm-resched-dscr tm-syscall tm-signal-msr-resv +tm-signal-stack diff --git a/tools/testing/selftests/powerpc/tm/Makefile b/tools/testing/selftests/powerpc/tm/Makefile index c6b4ca8b2812..e7ceff809fa0 100644 --- a/tools/testing/selftests/powerpc/tm/Makefile +++ b/tools/testing/selftests/powerpc/tm/Makefile @@ -1,4 +1,4 @@ -TEST_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv +TEST_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack all: $(TEST_PROGS) diff --git a/tools/testing/selftests/powerpc/tm/tm-signal-stack.c b/tools/testing/selftests/powerpc/tm/tm-signal-stack.c new file mode 100644 index 000000000000..e44a238c1d77 --- /dev/null +++ b/tools/testing/selftests/powerpc/tm/tm-signal-stack.c @@ -0,0 +1,76 @@ +/* + * Copyright 2015, Michael Neuling, IBM Corp. + * Licensed under GPLv2. + * + * Test the kernel's signal delievery code to ensure that we don't + * trelaim twice in the kernel signal delivery code. This can happen + * if we trigger a signal when in a transaction and the stack pointer + * is bogus. + * + * This test case registers a SEGV handler, sets the stack pointer + * (r1) to NULL, starts a transaction and then generates a SEGV. The + * SEGV should be handled but we exit here as the stack pointer is + * invalid and hance we can't sigreturn. We only need to check that + * this flow doesn't crash the kernel. + */ + +#include <unistd.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <stdlib.h> +#include <stdio.h> +#include <signal.h> + +#include "utils.h" +#include "tm.h" + +void signal_segv(int signum) +{ + /* This should never actually run since stack is foobar */ + exit(1); +} + +int tm_signal_stack() +{ + int pid; + + SKIP_IF(!have_htm()); + + pid = fork(); + if (pid < 0) + exit(1); + + if (pid) { /* Parent */ + /* + * It's likely the whole machine will crash here so if + * the child ever exits, we are good. + */ + wait(NULL); + return 0; + } + + /* + * The flow here is: + * 1) register a signal handler (so signal delievery occurs) + * 2) make stack pointer (r1) = NULL + * 3) start transaction + * 4) cause segv + */ + if (signal(SIGSEGV, signal_segv) == SIG_ERR) + exit(1); + asm volatile("li 1, 0 ;" /* stack ptr == NULL */ + "1:" + ".long 0x7C00051D ;" /* tbegin */ + "beq 1b ;" /* retry forever */ + ".long 0x7C0005DD ; ;" /* tsuspend */ + "ld 2, 0(1) ;" /* trigger segv" */ + : : : "memory"); + + /* This should never get here due to above segv */ + return 1; +} + +int main(void) +{ + return test_harness(tm_signal_stack, "tm_signal_stack"); +} |