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 <string.h> 23 #include <signal.h> 24 #include <unistd.h> 25 26 #include <altivec.h> 27 28 #include "utils.h" 29 #include "tm.h" 30 31 #define MAX_ATTEMPT 500000 32 33 #define NV_VMX_REGS 12 /* Number of non-volatile VMX registers */ 34 #define VMX20 20 /* First non-volatile register to check in vr20-31 subset */ 35 36 long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss); 37 38 static sig_atomic_t fail, broken; 39 40 /* Test only non-volatile registers, i.e. 12 vmx registers from vr20 to vr31 */ 41 vector int vms[] = { 42 /* First context will be set with these values, i.e. non-speculative */ 43 /* VMX20 , VMX21 , ... */ 44 { 1, 2, 3, 4},{ 5, 6, 7, 8},{ 9,10,11,12}, 45 {13,14,15,16},{17,18,19,20},{21,22,23,24}, 46 {25,26,27,28},{29,30,31,32},{33,34,35,36}, 47 {37,38,39,40},{41,42,43,44},{45,46,47,48}, 48 /* Second context will be set with these values, i.e. speculative */ 49 /* VMX20 , VMX21 , ... */ 50 { -1, -2, -3, -4},{ -5, -6, -7, -8},{ -9,-10,-11,-12}, 51 {-13,-14,-15,-16},{-17,-18,-19,-20},{-21,-22,-23,-24}, 52 {-25,-26,-27,-28},{-29,-30,-31,-32},{-33,-34,-35,-36}, 53 {-37,-38,-39,-40},{-41,-42,-43,-44},{-45,-46,-47,-48} 54 }; 55 56 static void signal_usr1(int signum, siginfo_t *info, void *uc) 57 { 58 int i, j; 59 ucontext_t *ucp = uc; 60 ucontext_t *tm_ucp = ucp->uc_link; 61 62 for (i = 0; i < NV_VMX_REGS; i++) { 63 /* Check first context. Print all mismatches. */ 64 fail = memcmp(ucp->uc_mcontext.v_regs->vrregs[VMX20 + i], 65 &vms[i], sizeof(vector int)); 66 if (fail) { 67 broken = 1; 68 printf("VMX%d (1st context) == 0x", VMX20 + i); 69 /* Print actual value in first context. */ 70 for (j = 0; j < 4; j++) 71 printf("%08x", ucp->uc_mcontext.v_regs->vrregs[VMX20 + i][j]); 72 printf(" instead of 0x"); 73 /* Print expected value. */ 74 for (j = 0; j < 4; j++) 75 printf("%08x", vms[i][j]); 76 printf(" (expected)\n"); 77 } 78 } 79 80 for (i = 0; i < NV_VMX_REGS; i++) { 81 /* Check second context. Print all mismatches. */ 82 fail = memcmp(tm_ucp->uc_mcontext.v_regs->vrregs[VMX20 + i], 83 &vms[NV_VMX_REGS + i], sizeof (vector int)); 84 if (fail) { 85 broken = 1; 86 printf("VMX%d (2nd context) == 0x", NV_VMX_REGS + i); 87 /* Print actual value in second context. */ 88 for (j = 0; j < 4; j++) 89 printf("%08x", tm_ucp->uc_mcontext.v_regs->vrregs[VMX20 + i][j]); 90 printf(" instead of 0x"); 91 /* Print expected value. */ 92 for (j = 0; j < 4; j++) 93 printf("%08x", vms[NV_VMX_REGS + i][j]); 94 printf(" (expected)\n"); 95 } 96 } 97 } 98 99 static int tm_signal_context_chk() 100 { 101 struct sigaction act; 102 int i; 103 long rc; 104 pid_t pid = getpid(); 105 106 SKIP_IF(!have_htm()); 107 108 act.sa_sigaction = signal_usr1; 109 sigemptyset(&act.sa_mask); 110 act.sa_flags = SA_SIGINFO; 111 if (sigaction(SIGUSR1, &act, NULL) < 0) { 112 perror("sigaction sigusr1"); 113 exit(1); 114 } 115 116 i = 0; 117 while (i < MAX_ATTEMPT && !broken) { 118 /* 119 * tm_signal_self_context_load will set both first and second 120 * contexts accordingly to the values passed through non-NULL 121 * array pointers to it, in that case 'vms', and invoke the 122 * signal handler installed for SIGUSR1. 123 */ 124 rc = tm_signal_self_context_load(pid, NULL, NULL, vms, NULL); 125 FAIL_IF(rc != pid); 126 i++; 127 } 128 129 return (broken); 130 } 131 132 int main(void) 133 { 134 return test_harness(tm_signal_context_chk, "tm_signal_context_chk_vmx"); 135 } 136