8141529: Fix handling of _JAVA_SR_SIGNUM
Reviewed-by: dholmes, stuefe, dsamersoff
--- a/hotspot/src/os/aix/vm/jsig.c Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/aix/vm/jsig.c Thu Nov 05 15:05:59 2015 +0100
@@ -1,6 +1,6 @@
/*
- * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
- * Copyright 2012, 2013 SAP AG. All rights reserved.
+ * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright 2012, 2015 SAP AG. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -36,26 +36,23 @@
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
+#include <stdint.h>
#define bool int
#define true 1
#define false 0
-// Highest so far on AIX 5.2 is SIGSAK (63)
-#define MAXSIGNUM 63
-#define MASK(sig) ((unsigned int)1 << sig)
+static struct sigaction sact[NSIG]; /* saved signal handlers */
+static sigset_t jvmsigs; /* Signals used by jvm. */
-static struct sigaction sact[MAXSIGNUM]; /* saved signal handlers */
-static unsigned int jvmsigs = 0; /* signals used by jvm */
-
-/* used to synchronize the installation of signal handlers */
+/* Used to synchronize the installation of signal handlers. */
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
static pthread_t tid = 0;
typedef void (*sa_handler_t)(int);
typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
-// signal_t is already defined on AIX
+// signal_t is already defined on AIX.
typedef sa_handler_t (*signal_like_function_t)(int, sa_handler_t);
typedef int (*sigaction_t)(int, const struct sigaction *, struct sigaction *);
@@ -68,7 +65,7 @@
static void signal_lock() {
pthread_mutex_lock(&mutex);
/* When the jvm is installing its set of signal handlers, threads
- * other than the jvm thread should wait */
+ * other than the jvm thread should wait. */
if (jvm_signal_installing) {
if (tid != pthread_self()) {
pthread_cond_wait(&cond, &mutex);
@@ -84,10 +81,10 @@
bool is_sigset) {
if (os_signal == NULL) {
if (!is_sigset) {
- // Aix: call functions directly instead of dlsym'ing them
+ // Aix: call functions directly instead of dlsym'ing them.
os_signal = signal;
} else {
- // Aix: call functions directly instead of dlsym'ing them
+ // Aix: call functions directly instead of dlsym'ing them.
os_signal = sigset;
}
if (os_signal == NULL) {
@@ -112,7 +109,7 @@
signal_lock();
- sigused = (MASK(sig) & jvmsigs) != 0;
+ sigused = sigismember(&jvmsigs, sig);
if (jvm_signal_installed && sigused) {
/* jvm has installed its signal handler for this signal. */
/* Save the handler. Don't really install it. */
@@ -129,7 +126,7 @@
save_signal_handler(sig, oldhandler);
/* Record the signals used by jvm */
- jvmsigs |= MASK(sig);
+ sigaddset(&jvmsigs, sig);
signal_unlock();
return oldhandler;
@@ -149,12 +146,12 @@
sa_handler_t sigset(int sig, sa_handler_t disp) {
return set_signal(sig, disp, true);
- }
+}
static int call_os_sigaction(int sig, const struct sigaction *act,
struct sigaction *oact) {
if (os_sigaction == NULL) {
- // Aix: call functions directly instead of dlsym'ing them
+ // Aix: call functions directly instead of dlsym'ing them.
os_sigaction = sigaction;
if (os_sigaction == NULL) {
printf("%s\n", dlerror());
@@ -171,7 +168,7 @@
signal_lock();
- sigused = (MASK(sig) & jvmsigs) != 0;
+ sigused = sigismember(&jvmsigs, sig);
if (jvm_signal_installed && sigused) {
/* jvm has installed its signal handler for this signal. */
/* Save the handler. Don't really install it. */
@@ -193,8 +190,8 @@
*oact = oldAct;
}
- /* Record the signals used by jvm */
- jvmsigs |= MASK(sig);
+ /* Record the signals used by jvm. */
+ sigaddset(&jvmsigs, sig);
signal_unlock();
return res;
@@ -208,9 +205,10 @@
}
}
-/* The three functions for the jvm to call into */
+/* The three functions for the jvm to call into. */
void JVM_begin_signal_setting() {
signal_lock();
+ sigemptyset(&jvmsigs);
jvm_signal_installing = true;
tid = pthread_self();
signal_unlock();
@@ -226,7 +224,7 @@
struct sigaction *JVM_get_signal_action(int sig) {
/* Does race condition make sense here? */
- if ((MASK(sig) & jvmsigs) != 0) {
+ if (sigismember(&jvmsigs, sig)) {
return &sact[sig];
}
return NULL;
--- a/hotspot/src/os/aix/vm/os_aix.cpp Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/aix/vm/os_aix.cpp Thu Nov 05 15:05:59 2015 +0100
@@ -2769,8 +2769,12 @@
// Get signal number to use for suspend/resume
if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
int sig = ::strtol(s, 0, 10);
- if (sig > 0 || sig < NSIG) {
+ if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
+ sig < NSIG) { // Must be legal signal and fit into sigflags[].
SR_signum = sig;
+ } else {
+ warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
+ sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
}
}
@@ -2966,8 +2970,8 @@
bool os::Aix::signal_handlers_are_installed = false;
// For signal-chaining
-struct sigaction os::Aix::sigact[MAXSIGNUM];
-unsigned int os::Aix::sigs = 0;
+struct sigaction sigact[NSIG];
+sigset_t sigs;
bool os::Aix::libjsig_is_loaded = false;
typedef struct sigaction *(*get_signal_t)(int);
get_signal_t os::Aix::get_signal_action = NULL;
@@ -3045,29 +3049,31 @@
}
struct sigaction* os::Aix::get_preinstalled_handler(int sig) {
- if ((((unsigned int)1 << sig) & sigs) != 0) {
+ if (sigismember(&sigs, sig)) {
return &sigact[sig];
}
return NULL;
}
void os::Aix::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
sigact[sig] = oldAct;
- sigs |= (unsigned int)1 << sig;
+ sigaddset(&sigs, sig);
}
// for diagnostic
-int os::Aix::sigflags[MAXSIGNUM];
+int sigflags[NSIG];
int os::Aix::get_our_sigflags(int sig) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
return sigflags[sig];
}
void os::Aix::set_our_sigflags(int sig, int flags) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
- sigflags[sig] = flags;
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
+ if (sig > 0 && sig < NSIG) {
+ sigflags[sig] = flags;
+ }
}
void os::Aix::set_signal_handler(int sig, bool set_installed) {
@@ -3107,7 +3113,7 @@
sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
}
// Save flags, which are set by ours
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
sigflags[sig] = sigAct.sa_flags;
int ret = sigaction(sig, &sigAct, &oldAct);
@@ -3140,10 +3146,11 @@
assert(UseSignalChaining, "should enable signal-chaining");
}
if (libjsig_is_loaded) {
- // Tell libjsig jvm is setting signal handlers
+ // Tell libjsig jvm is setting signal handlers.
(*begin_signal_setting)();
}
+ ::sigemptyset(&sigs);
set_signal_handler(SIGSEGV, true);
set_signal_handler(SIGPIPE, true);
set_signal_handler(SIGBUS, true);
--- a/hotspot/src/os/aix/vm/os_aix.hpp Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/aix/vm/os_aix.hpp Thu Nov 05 15:05:59 2015 +0100
@@ -34,15 +34,9 @@
class Aix {
friend class os;
- // For signal-chaining
- // highest so far (AIX 5.2 - 6.1) is SIGSAK (63)
-#define MAXSIGNUM 63
// Length of strings included in the libperfstat structures.
#define IDENTIFIER_LENGTH 64
- static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
- static unsigned int sigs; // mask of signals that have
- // preinstalled signal handlers
static bool libjsig_is_loaded; // libjsig that interposes sigaction(),
// __sigaction(), signal() is loaded
static struct sigaction *(*get_signal_action)(int);
@@ -51,9 +45,6 @@
static void check_signal_handler(int sig);
- // For signal flags diagnostics
- static int sigflags[MAXSIGNUM];
-
protected:
static julong _physical_memory;
--- a/hotspot/src/os/bsd/vm/jsig.c Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/bsd/vm/jsig.c Thu Nov 05 15:05:59 2015 +0100
@@ -36,12 +36,14 @@
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
+#include <stdint.h>
-#define MAXSIGNUM 32
-#define MASK(sig) ((unsigned int)1 << sig)
-
-static struct sigaction sact[MAXSIGNUM]; /* saved signal handlers */
-static unsigned int jvmsigs = 0; /* signals used by jvm */
+#define MASK(sig) ((uint32_t)1 << (sig-1)) // 0 is not a signal.
+#if (32 < NSIG-1)
+#error "Not all signals can be encoded in jvmsigs. Adapt its type!"
+#endif
+static struct sigaction sact[NSIG]; /* saved signal handlers */
+static uint32_t jvmsigs = 0; /* signals used by jvm */
static __thread bool reentry = false; /* prevent reentry deadlock (per-thread) */
/* used to synchronize the installation of signal handlers */
--- a/hotspot/src/os/bsd/vm/os_bsd.cpp Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/bsd/vm/os_bsd.cpp Thu Nov 05 15:05:59 2015 +0100
@@ -2831,8 +2831,12 @@
// Get signal number to use for suspend/resume
if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
int sig = ::strtol(s, 0, 10);
- if (sig > 0 || sig < NSIG) {
+ if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
+ sig < NSIG) { // Must be legal signal and fit into sigflags[].
SR_signum = sig;
+ } else {
+ warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
+ sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
}
}
@@ -2985,8 +2989,11 @@
bool os::Bsd::signal_handlers_are_installed = false;
// For signal-chaining
-struct sigaction os::Bsd::sigact[MAXSIGNUM];
-unsigned int os::Bsd::sigs = 0;
+struct sigaction sigact[NSIG];
+uint32_t sigs = 0;
+#if (32 < NSIG-1)
+#error "Not all signals can be encoded in sigs. Adapt its type!"
+#endif
bool os::Bsd::libjsig_is_loaded = false;
typedef struct sigaction *(*get_signal_t)(int);
get_signal_t os::Bsd::get_signal_action = NULL;
@@ -3064,29 +3071,31 @@
}
struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
- if ((((unsigned int)1 << sig) & sigs) != 0) {
+ if ((((uint32_t)1 << (sig-1)) & sigs) != 0) {
return &sigact[sig];
}
return NULL;
}
void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
sigact[sig] = oldAct;
- sigs |= (unsigned int)1 << sig;
+ sigs |= (uint32_t)1 << (sig-1);
}
// for diagnostic
-int os::Bsd::sigflags[MAXSIGNUM];
+int sigflags[NSIG];
int os::Bsd::get_our_sigflags(int sig) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
return sigflags[sig];
}
void os::Bsd::set_our_sigflags(int sig, int flags) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
- sigflags[sig] = flags;
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
+ if (sig > 0 && sig < NSIG) {
+ sigflags[sig] = flags;
+ }
}
void os::Bsd::set_signal_handler(int sig, bool set_installed) {
@@ -3137,7 +3146,7 @@
#endif
// Save flags, which are set by ours
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
sigflags[sig] = sigAct.sa_flags;
int ret = sigaction(sig, &sigAct, &oldAct);
--- a/hotspot/src/os/bsd/vm/os_bsd.hpp Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/bsd/vm/os_bsd.hpp Thu Nov 05 15:05:59 2015 +0100
@@ -40,10 +40,6 @@
friend class os;
// For signal-chaining
-#define MAXSIGNUM 32
- static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
- static unsigned int sigs; // mask of signals that have
- // preinstalled signal handlers
static bool libjsig_is_loaded; // libjsig that interposes sigaction(),
// __sigaction(), signal() is loaded
static struct sigaction *(*get_signal_action)(int);
@@ -52,9 +48,6 @@
static void check_signal_handler(int sig);
- // For signal flags diagnostics
- static int sigflags[MAXSIGNUM];
-
#ifdef __APPLE__
// mach_absolute_time
static mach_timebase_info_data_t _timebase_info;
--- a/hotspot/src/os/linux/vm/jsig.c Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/linux/vm/jsig.c Thu Nov 05 15:05:59 2015 +0100
@@ -35,16 +35,19 @@
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
+#include <stdint.h>
#define bool int
#define true 1
#define false 0
-#define MAXSIGNUM 32
-#define MASK(sig) ((unsigned int)1 << sig)
-
-static struct sigaction sact[MAXSIGNUM]; /* saved signal handlers */
-static unsigned int jvmsigs = 0; /* signals used by jvm */
+#define MASK(sig) ((uint64_t)1 << (sig-1)) // 0 is not a signal.
+// Check whether all signals fit into jvmsigs. -1 as MASK shifts by -1.
+#if (64 < NSIG-1)
+#error "Not all signals can be encoded in jvmsigs. Adapt its type!"
+#endif
+static struct sigaction sact[NSIG]; /* saved signal handlers */
+static uint64_t jvmsigs = 0; /* signals used by jvm */
/* used to synchronize the installation of signal handlers */
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
@@ -107,7 +110,7 @@
signal_lock();
- sigused = (sig < MAXSIGNUM) && ((MASK(sig) & jvmsigs) != 0);
+ sigused = (sig < NSIG) && ((MASK(sig) & jvmsigs) != 0);
if (jvm_signal_installed && sigused) {
/* jvm has installed its signal handler for this signal. */
/* Save the handler. Don't really install it. */
@@ -116,7 +119,7 @@
signal_unlock();
return oldhandler;
- } else if (sig < MAXSIGNUM && jvm_signal_installing) {
+ } else if (sig < NSIG && jvm_signal_installing) {
/* jvm is installing its signal handlers. Install the new
* handlers and save the old ones. jvm uses sigaction().
* Leave the piece here just in case. */
@@ -165,7 +168,7 @@
signal_lock();
- sigused = (sig < MAXSIGNUM) && ((MASK(sig) & jvmsigs) != 0);
+ sigused = (sig < NSIG) && ((MASK(sig) & jvmsigs) != 0);
if (jvm_signal_installed && sigused) {
/* jvm has installed its signal handler for this signal. */
/* Save the handler. Don't really install it. */
@@ -178,7 +181,7 @@
signal_unlock();
return 0;
- } else if (sig < MAXSIGNUM && jvm_signal_installing) {
+ } else if (sig < NSIG && jvm_signal_installing) {
/* jvm is installing its signal handlers. Install the new
* handlers and save the old ones. */
res = call_os_sigaction(sig, act, &oldAct);
--- a/hotspot/src/os/linux/vm/os_linux.cpp Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/linux/vm/os_linux.cpp Thu Nov 05 15:05:59 2015 +0100
@@ -3989,15 +3989,19 @@
errno = old_errno;
}
-
static int SR_initialize() {
struct sigaction act;
char *s;
+
// Get signal number to use for suspend/resume
if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
int sig = ::strtol(s, 0, 10);
- if (sig > 0 || sig < _NSIG) {
+ if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
+ sig < NSIG) { // Must be legal signal and fit into sigflags[].
SR_signum = sig;
+ } else {
+ warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
+ sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
}
}
@@ -4151,8 +4155,11 @@
bool os::Linux::signal_handlers_are_installed = false;
// For signal-chaining
-struct sigaction os::Linux::sigact[MAXSIGNUM];
-unsigned int os::Linux::sigs = 0;
+struct sigaction sigact[NSIG];
+uint64_t sigs = 0;
+#if (64 < NSIG-1)
+#error "Not all signals can be encoded in sigs. Adapt its type!"
+#endif
bool os::Linux::libjsig_is_loaded = false;
typedef struct sigaction *(*get_signal_t)(int);
get_signal_t os::Linux::get_signal_action = NULL;
@@ -4230,29 +4237,29 @@
}
struct sigaction* os::Linux::get_preinstalled_handler(int sig) {
- if ((((unsigned int)1 << sig) & sigs) != 0) {
+ if ((((uint64_t)1 << (sig-1)) & sigs) != 0) {
return &sigact[sig];
}
return NULL;
}
void os::Linux::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
sigact[sig] = oldAct;
- sigs |= (unsigned int)1 << sig;
+ sigs |= (uint64_t)1 << (sig-1);
}
// for diagnostic
-int os::Linux::sigflags[MAXSIGNUM];
+int sigflags[NSIG];
int os::Linux::get_our_sigflags(int sig) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
return sigflags[sig];
}
void os::Linux::set_our_sigflags(int sig, int flags) {
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
- if (sig > 0 && sig < MAXSIGNUM) {
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
+ if (sig > 0 && sig < NSIG) {
sigflags[sig] = flags;
}
}
@@ -4292,7 +4299,7 @@
sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
}
// Save flags, which are set by ours
- assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
+ assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
sigflags[sig] = sigAct.sa_flags;
int ret = sigaction(sig, &sigAct, &oldAct);
--- a/hotspot/src/os/linux/vm/os_linux.hpp Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/linux/vm/os_linux.hpp Thu Nov 05 15:05:59 2015 +0100
@@ -34,11 +34,6 @@
friend class os;
friend class TestReserveMemorySpecial;
- // For signal-chaining
-#define MAXSIGNUM 32
- static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
- static unsigned int sigs; // mask of signals that have
- // preinstalled signal handlers
static bool libjsig_is_loaded; // libjsig that interposes sigaction(),
// __sigaction(), signal() is loaded
static struct sigaction *(*get_signal_action)(int);
@@ -47,9 +42,6 @@
static void check_signal_handler(int sig);
- // For signal flags diagnostics
- static int sigflags[MAXSIGNUM];
-
static int (*_clock_gettime)(clockid_t, struct timespec *);
static int (*_pthread_getcpuclockid)(pthread_t, clockid_t *);
static int (*_pthread_setname_np)(pthread_t, const char*);
--- a/hotspot/src/os/solaris/vm/os_solaris.hpp Mon Nov 16 18:50:55 2015 -0500
+++ b/hotspot/src/os/solaris/vm/os_solaris.hpp Thu Nov 05 15:05:59 2015 +0100
@@ -113,9 +113,6 @@
static void try_enable_extended_io();
- // For signal-chaining
- static unsigned long sigs; // mask of signals that have
- // preinstalled signal handlers
static struct sigaction *(*get_signal_action)(int);
static struct sigaction *get_preinstalled_handler(int);
static int (*get_libjsig_version)();