X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Flinux-os.c;h=4c6ef832e79dfd8d022fe13de4c592d9fdc2c679;hb=4efb45cc0b0b9c3109d7cfd72f3f35de2ca4727e;hp=25fd43373ee8d1c54d6ee5f9eba171cdf203c3d6;hpb=a3b0216d19e2451899cb4acc1a48fa63853ea943;p=sbcl.git diff --git a/src/runtime/linux-os.c b/src/runtime/linux-os.c index 25fd433..4c6ef83 100644 --- a/src/runtime/linux-os.c +++ b/src/runtime/linux-os.c @@ -34,8 +34,10 @@ #include "runtime.h" #include "genesis/static-symbols.h" #include "genesis/fdefn.h" + #include #include +#include #include #include @@ -52,10 +54,17 @@ #include "gencgc-internal.h" #endif +#ifdef LISP_FEATURE_X86 +/* Prototype for personality(2). Done inline here since the header file + * for this isn't available on old versions of glibc. */ +int personality (unsigned long); +#endif + size_t os_vm_page_size; -#ifdef LISP_FEATURE_SB_THREAD -#include +#if defined(LISP_FEATURE_SB_THREAD) && !defined(LISP_FEATURE_SB_LUTEX) && !defined(LISP_FEATURE_SB_PTHREAD_FUTEX) +#include +#include #include /* values taken from the kernel's linux/futex.h. This header file @@ -66,18 +75,27 @@ size_t os_vm_page_size; #define FUTEX_FD (2) #define FUTEX_REQUEUE (3) -#define __NR_sys_futex __NR_futex - -_syscall4(int,sys_futex, - int *, futex, - int, op, - int, val, - struct timespec *, rel); +#define sys_futex sbcl_sys_futex +static inline int sys_futex (void *futex, int op, int val, struct timespec *rel) +{ + return syscall (SYS_futex, futex, op, val, rel); +} int futex_wait(int *lock_word, int oldval) { - int t= sys_futex(lock_word,FUTEX_WAIT,oldval, 0); + int t; + again: + t = sys_futex(lock_word,FUTEX_WAIT,oldval, 0); + + /* Interrupted FUTEX_WAIT calls may return early. + * + * If someone manages to wake the futex while we're spinning + * around it, we will just return with -1 and errno EWOULDBLOCK, + * because the value has changed, so that's ok. */ + if (t != 0 && errno == EINTR) + goto again; + return t; } @@ -90,27 +108,60 @@ futex_wake(int *lock_word, int n) int linux_sparc_siginfo_bug = 0; + +/* This variable was in real use for a few months, basically for + * storing autodetected information about whether the Linux + * installation was recent enough to support SBCL threads, and make + * some run-time decisions based on that. But this turned out to be + * unstable, so now we just flat-out refuse to start on the old installations + * when thread support has been compiled in. + * + * Unfortunately, in the meanwhile Slime started depending on this + * variable for deciding which communication style to use. So even + * though this variable looks unused, it shouldn't be deleted until + * it's no longer used in the versions of Slime that people are + * likely to download first. -- JES, 2006-06-07 + */ int linux_no_threads_p = 0; +#ifdef LISP_FEATURE_SB_THREAD +int +isnptl (void) +{ + size_t n = confstr (_CS_GNU_LIBPTHREAD_VERSION, NULL, 0); + if (n > 0) { + char *buf = alloca (n); + confstr (_CS_GNU_LIBPTHREAD_VERSION, buf, n); + if (strstr (buf, "NPTL")) { + return 1; + } + } + return 0; +} +#endif + void -os_init(void) +os_init(char *argv[], char *envp[]) { /* Conduct various version checks: do we have enough mmap(), is * this a sparc running 2.2, can we do threads? */ -#ifdef LISP_FEATURE_SB_THREAD +#if defined(LISP_FEATURE_SB_THREAD) && !defined(LISP_FEATURE_SB_LUTEX) && !defined(LISP_FEATURE_SB_PTHREAD_FUTEX) int *futex=0; #endif struct utsname name; int major_version; int minor_version; + int patch_version; char *p; uname(&name); p=name.release; major_version = atoi(p); p=strchr(p,'.')+1; minor_version = atoi(p); + p=strchr(p,'.')+1; + patch_version = atoi(p); if (major_version<2) { - lose("linux kernel version too old: major version=%d (can't run in version < 2.0.0)", + lose("linux kernel version too old: major version=%d (can't run in version < 2.0.0)\n", major_version); } if (!(major_version>2 || minor_version >= 4)) { @@ -120,12 +171,77 @@ os_init(void) #endif } #ifdef LISP_FEATURE_SB_THREAD +#if !defined(LISP_FEATURE_SB_LUTEX) && !defined(LISP_FEATURE_SB_PTHREAD_FUTEX) futex_wait(futex,-1); - if(errno==ENOSYS) linux_no_threads_p = 1; - if(linux_no_threads_p) - fprintf(stderr,"Linux with NPTL support (e.g. kernel 2.6 or newer) required for \nthread-enabled SBCL. Disabling thread support.\n\n"); + if(errno==ENOSYS) { + lose("This version of SBCL is compiled with threading support, but your kernel\n" + "is too old to support this. Please use a more recent kernel or\n" + "a version of SBCL without threading support.\n"); + } +#endif + if(! isnptl()) { + lose("This version of SBCL only works correctly with the NPTL threading\n" + "library. Please use a newer glibc, use an older SBCL, or stop using\n" + "LD_ASSUME_KERNEL\n"); + } #endif os_vm_page_size = getpagesize(); + + /* KLUDGE: Disable memory randomization on new Linux kernels + * by setting a personality flag and re-executing. (We need + * to re-execute, since the memory maps that can conflict with + * the SBCL spaces have already been done at this point). + * + * Since randomization is currently implemented only on x86 kernels, + * don't do this trick on other platforms. + */ +#ifdef LISP_FEATURE_X86 + if ((major_version == 2 + /* Some old kernels will apparently lose unsupported personality flags + * on exec() */ + && ((minor_version == 6 && patch_version >= 11) + || (minor_version > 6))) + || major_version >= 3) + { + int pers = personality(0xffffffffUL); + /* 0x40000 aka. ADDR_NO_RANDOMIZE */ + if (!(pers & 0x40000)) { + int retval = personality(pers | 0x40000); + /* Allegedly some Linux kernels (the reported case was + * "hardened Linux 2.6.7") won't set the new personality, + * but nor will they return -1 for an error. So as a + * workaround query the new personality... + */ + int newpers = personality(0xffffffffUL); + /* ... and don't re-execute if either the setting resulted + * in an error or if the value didn't change. Otherwise + * this might result in an infinite loop. + */ + if (retval != -1 && newpers != pers) { + /* Use /proc/self/exe instead of trying to figure out + * the executable path from PATH and argv[0], since + * that's unreliable. We follow the symlink instead of + * executing the file directly in order to prevent top + * from displaying the name of the process as "exe". */ + char runtime[PATH_MAX+1]; + int i = readlink("/proc/self/exe", runtime, PATH_MAX); + if (i != -1) { + runtime[i] = '\0'; + execve(runtime, argv, envp); + } + } + /* Either changing the personality or execve() failed. Either + * way we might as well continue, and hope that the random + * memory maps are ok this time around. + */ + fprintf(stderr, "WARNING: Couldn't re-execute SBCL with the proper personality flags (maybe /proc isn't mounted?). Trying to continue anyway.\n"); + } + } + /* Use SSE detector. Recent versions of Linux enable SSE support + * on SSE capable CPUs. */ + /* FIXME: Are there any old versions that does not support SSE? */ + fast_bzero_pointer = fast_bzero_detect; +#endif } @@ -150,11 +266,17 @@ os_validate(os_vm_address_t addr, os_vm_size_t len) } #endif actual = mmap(addr, len, OS_VM_PROT_ALL, flags, -1, 0); - if (actual == MAP_FAILED || (addr && (addr!=actual))) { + if (actual == MAP_FAILED) { perror("mmap"); return 0; /* caller should check this */ } + if (addr && (addr!=actual)) { + fprintf(stderr, "mmap: wanted %lu bytes at %p, actually mapped at %p\n", + (unsigned long) len, addr, actual); + return 0; + } + #ifdef LISP_FEATURE_ALPHA len=(len+(os_vm_page_size-1))&(~(os_vm_page_size-1)); @@ -181,7 +303,7 @@ os_map(int fd, int offset, os_vm_address_t addr, os_vm_size_t len) fd, (off_t) offset); if (actual == MAP_FAILED || (addr && (addr != actual))) { perror("mmap"); - lose("unexpected mmap(..) failure"); + lose("unexpected mmap(..) failure\n"); } return actual; @@ -191,7 +313,14 @@ void os_protect(os_vm_address_t address, os_vm_size_t length, os_vm_prot_t prot) { if (mprotect(address, length, prot) == -1) { - perror("mprotect"); + if (errno == ENOMEM) { + lose("An mprotect call failed with ENOMEM. This probably means that the maximum amount\n" + "of separate memory mappings was exceeded. To fix the problem, either increase\n" + "the maximum with e.g. 'echo 262144 > /proc/sys/vm/max_map_count' or recompile\n" + "SBCL with a larger value for GENCGC-PAGE-SIZE in 'src/target/parms.lisp'."); + } else { + perror("mprotect"); + } } } @@ -226,34 +355,15 @@ is_valid_lisp_addr(os_vm_address_t addr) * any OS-dependent special low-level handling for signals */ - -#if defined LISP_FEATURE_GENCGC - /* - * The GENCGC needs to be hooked into whatever signal is raised for + * The GC needs to be hooked into whatever signal is raised for * page fault on this OS. */ static void sigsegv_handler(int signal, siginfo_t *info, void* void_context) { os_context_t *context = arch_os_get_context(&void_context); - void* fault_addr = (void*)info->si_addr; - if (!gencgc_handle_wp_violation(fault_addr)) - if(!handle_guard_page_triggered(context,fault_addr)) -#ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK - arrange_return_to_lisp_function(context, SymbolFunction(MEMORY_FAULT_ERROR)); -#else - interrupt_handle_now(signal, info, context); -#endif -} - -#else - -static void -sigsegv_handler(int signal, siginfo_t *info, void* void_context) -{ - os_context_t *context = arch_os_get_context(&void_context); - os_vm_address_t addr = arch_get_bad_addr(signal,info,context); + os_vm_address_t addr = arch_get_bad_addr(signal, info, context); #ifdef LISP_FEATURE_ALPHA /* Alpha stuff: This is the end of a pseudo-atomic section during @@ -264,18 +374,25 @@ sigsegv_handler(int signal, siginfo_t *info, void* void_context) At the end of the atomic section we tried to write to reg_ALLOC, got a SIGSEGV (there's nothing mapped there) so ended up here. */ if (addr != NULL && - *os_context_register_addr(context,reg_ALLOC) & (1L<<63)){ - *os_context_register_addr(context,reg_ALLOC) -= (1L<<63); + *os_context_register_addr(context, reg_ALLOC) & (1L<<63)) { + *os_context_register_addr(context, reg_ALLOC) -= (1L<<63); interrupt_handle_pending(context); return; } #endif - if(!interrupt_maybe_gc(signal, info, context)) - if(!handle_guard_page_triggered(context,addr)) +#ifdef LISP_FEATURE_GENCGC + if (!gencgc_handle_wp_violation(addr)) +#else + if (!interrupt_maybe_gc(signal, info, context)) +#endif + if (!handle_guard_page_triggered(context, addr)) +#ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK + lisp_memory_fault_error(context, addr); +#else interrupt_handle_now(signal, info, context); -} #endif +} void os_install_interrupt_handlers(void) @@ -289,3 +406,18 @@ os_install_interrupt_handlers(void) sig_stop_for_gc_handler); #endif } + +char * +os_get_runtime_executable_path() +{ + char path[PATH_MAX + 1]; + int size; + + size = readlink("/proc/self/exe", path, sizeof(path)-1); + if (size < 0) + return NULL; + else + path[size] = '\0'; + + return copied_string(path); +}