1 /* 2 * This file and its contents are supplied under the terms of the 3 * Common Development and Distribution License ("CDDL"), version 1.0. 4 * You may only use this file in accordance with the terms of version 5 * 1.0 of the CDDL. 6 * 7 * A full copy of the text of the CDDL should have accompanied this 8 * source. A copy of the CDDL is also available via the Internet at 9 * http://www.illumos.org/license/CDDL. 10 */ 11 12 /* 13 * Copyright 2018 Joyent, Inc. 14 */ 15 16 #include <sys/types.h> 17 #include <sys/sysi86.h> 18 #include <sys/segments.h> 19 #include <sys/segment.h> 20 #include <unistd.h> 21 #include <string.h> 22 #include <errno.h> 23 #include <pthread.h> 24 #include <err.h> 25 26 char foo[4096]; 27 28 static void * 29 donothing(void *nothing) 30 { 31 (void) sleep(5); 32 return (NULL); 33 } 34 35 int 36 main(void) 37 { 38 pthread_t tid; 39 40 /* 41 * This first is similar to what sbcl does in some variants. Note the 42 * SDT_MEMRW (not SDT_MEMRWA) so we check that the kernel is forcing the 43 * 'accessed' bit too. 44 */ 45 int sel = SEL_LDT(7); 46 47 struct ssd ssd = { sel, (unsigned long)&foo, 4096, 48 SDT_MEMRW | (SEL_UPL << 5) | (1 << 7), 0x4 }; 49 50 if (sysi86(SI86DSCR, &ssd) < 0) 51 err(-1, "failed to setup segment"); 52 53 __asm__ __volatile__("mov %0, %%fs" : : "r" (sel)); 54 55 ssd.acc1 = 0; 56 57 if (sysi86(SI86DSCR, &ssd) == 0) 58 errx(-1, "removed in-use segment?"); 59 60 __asm__ __volatile__("mov %0, %%fs" : : "r" (0)); 61 62 if (sysi86(SI86DSCR, &ssd) < 0) 63 err(-1, "failed to remove segment"); 64 65 for (int i = 0; i < MAXNLDT; i++) { 66 ssd.sel = SEL_LDT(i); 67 (void) sysi86(SI86DSCR, &ssd); 68 } 69 70 for (int i = 0; i < 10; i++) 71 (void) pthread_create(&tid, NULL, donothing, NULL); 72 73 if (forkall() == 0) { 74 (void) sleep(2); 75 _exit(0); 76 } 77 78 (void) sleep(6); 79 return (0); 80 } 81