1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright 2016, Cyril Bur, IBM Corp. 4 * 5 * Test the kernel's signal frame code. 6 * 7 * The kernel sets up two sets of ucontexts if the signal was to be 8 * delivered while the thread was in a transaction (referred too as 9 * first and second contexts). 10 * Expected behaviour is that the checkpointed state is in the user 11 * context passed to the signal handler (first context). The speculated 12 * state can be accessed with the uc_link pointer (second context). 13 * 14 * The rationale for this is that if TM unaware code (which linked 15 * against TM libs) installs a signal handler it will not know of the 16 * speculative nature of the 'live' registers and may infer the wrong 17 * thing. 18 */ 19 20 #include <stdlib.h> 21 #include <stdio.h> 22 #include <signal.h> 23 #include <unistd.h> 24 25 #include <altivec.h> 26 27 #include "utils.h" 28 #include "tm.h" 29 30 #define MAX_ATTEMPT 500000 31 32 #define NV_GPR_REGS 18 /* Number of non-volatile GPR registers */ 33 #define R14 14 /* First non-volatile register to check in r14-r31 subset */ 34 35 long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss); 36 37 static sig_atomic_t fail, broken; 38 39 /* Test only non-volatile general purpose registers, i.e. r14-r31 */ 40 static long gprs[] = { 41 /* First context will be set with these values, i.e. non-speculative */ 42 /* R14, R15, ... */ 43 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 44 /* Second context will be set with these values, i.e. speculative */ 45 /* R14, R15, ... */ 46 -1,-2,-3,-4,-5,-6,-7,-8,-9,-10,-11,-12,-13,-14,-15,-16,-17,-18 47 }; 48 49 static void signal_usr1(int signum, siginfo_t *info, void *uc) 50 { 51 int i; 52 ucontext_t *ucp = uc; 53 ucontext_t *tm_ucp = ucp->uc_link; 54 55 /* Check first context. Print all mismatches. */ 56 for (i = 0; i < NV_GPR_REGS; i++) { 57 fail = (ucp->uc_mcontext.gp_regs[R14 + i] != gprs[i]); 58 if (fail) { 59 broken = 1; 60 printf("GPR%d (1st context) == %lu instead of %lu (expected)\n", 61 R14 + i, ucp->uc_mcontext.gp_regs[R14 + i], gprs[i]); 62 } 63 } 64 65 /* Check second context. Print all mismatches. */ 66 for (i = 0; i < NV_GPR_REGS; i++) { 67 fail = (tm_ucp->uc_mcontext.gp_regs[R14 + i] != gprs[NV_GPR_REGS + i]); 68 if (fail) { 69 broken = 1; 70 printf("GPR%d (2nd context) == %lu instead of %lu (expected)\n", 71 R14 + i, tm_ucp->uc_mcontext.gp_regs[R14 + i], gprs[NV_GPR_REGS + i]); 72 } 73 } 74 } 75 76 static int tm_signal_context_chk_gpr() 77 { 78 struct sigaction act; 79 int i; 80 long rc; 81 pid_t pid = getpid(); 82 83 SKIP_IF(!have_htm()); 84 SKIP_IF(htm_is_synthetic()); 85 86 act.sa_sigaction = signal_usr1; 87 sigemptyset(&act.sa_mask); 88 act.sa_flags = SA_SIGINFO; 89 if (sigaction(SIGUSR1, &act, NULL) < 0) { 90 perror("sigaction sigusr1"); 91 exit(1); 92 } 93 94 i = 0; 95 while (i < MAX_ATTEMPT && !broken) { 96 /* 97 * tm_signal_self_context_load will set both first and second 98 * contexts accordingly to the values passed through non-NULL 99 * array pointers to it, in that case 'gprs', and invoke the 100 * signal handler installed for SIGUSR1. 101 */ 102 rc = tm_signal_self_context_load(pid, gprs, NULL, NULL, NULL); 103 FAIL_IF(rc != pid); 104 i++; 105 } 106 107 return broken; 108 } 109 110 int main(void) 111 { 112 return test_harness(tm_signal_context_chk_gpr, "tm_signal_context_chk_gpr"); 113 } 114