$ ./tools/testing/kunit/kunit.py run --make_options=CC=/usr/bin/gcc-6
$ lcov -t "my_kunit_tests" -o coverage.info -c -d .kunit/ --gcov-tool=/usr/bin/gcov-6
+Alternatively, LLVM-based toolchains can also be used:
+
+.. code-block:: bash
+
+ # Build with LLVM and append coverage options to the current config
+ $ ./tools/testing/kunit/kunit.py run --make_options LLVM=1 --kunitconfig=.kunit/ --kunitconfig=tools/testing/kunit/configs/coverage_uml.config
+ $ llvm-profdata merge -sparse default.profraw -o default.profdata
+ $ llvm-cov export --format=lcov .kunit/vmlinux -instr-profile default.profdata > coverage.info
+ # The coverage.info file is in lcov-compatible format and it can be used to e.g. generate HTML report
+ $ genhtml -o /tmp/coverage_html coverage.info
+
Running tests manually
======================
#
GPROF_OPT += -pg
+
+ifdef CONFIG_CC_IS_CLANG
+GCOV_OPT += -fprofile-instr-generate -fcoverage-mapping
+else
GCOV_OPT += -fprofile-arcs -ftest-coverage
+endif
CFLAGS-$(CONFIG_GCOV) += $(GCOV_OPT)
CFLAGS-$(CONFIG_GPROF) += $(GPROF_OPT)
int pipe_fd;
};
-static int winch_thread(void *arg)
+static __noreturn int winch_thread(void *arg)
{
struct winch_data *data = arg;
sigset_t sigs;
pipe_fd = data->pipe_fd;
count = write(pipe_fd, &c, sizeof(c));
if (count != sizeof(c))
- printk(UM_KERN_ERR "winch_thread : failed to write "
- "synchronization byte, err = %d\n", -count);
+ os_info("winch_thread : failed to write synchronization byte, err = %d\n",
+ -count);
/*
* We are not using SIG_IGN on purpose, so don't fix it as I thought to
sigfillset(&sigs);
/* Block all signals possible. */
if (sigprocmask(SIG_SETMASK, &sigs, NULL) < 0) {
- printk(UM_KERN_ERR "winch_thread : sigprocmask failed, "
- "errno = %d\n", errno);
- exit(1);
+ os_info("winch_thread : sigprocmask failed, errno = %d\n",
+ errno);
+ goto wait_kill;
}
/* In sigsuspend(), block anything else than SIGWINCH. */
sigdelset(&sigs, SIGWINCH);
if (setsid() < 0) {
- printk(UM_KERN_ERR "winch_thread : setsid failed, errno = %d\n",
+ os_info("winch_thread : setsid failed, errno = %d\n",
errno);
- exit(1);
+ goto wait_kill;
}
if (ioctl(pty_fd, TIOCSCTTY, 0) < 0) {
- printk(UM_KERN_ERR "winch_thread : TIOCSCTTY failed on "
- "fd %d err = %d\n", pty_fd, errno);
- exit(1);
+ os_info("winch_thread : TIOCSCTTY failed on "
+ "fd %d err = %d\n", pty_fd, errno);
+ goto wait_kill;
}
if (tcsetpgrp(pty_fd, os_getpid()) < 0) {
- printk(UM_KERN_ERR "winch_thread : tcsetpgrp failed on "
- "fd %d err = %d\n", pty_fd, errno);
- exit(1);
+ os_info("winch_thread : tcsetpgrp failed on fd %d err = %d\n",
+ pty_fd, errno);
+ goto wait_kill;
}
/*
*/
count = read(pipe_fd, &c, sizeof(c));
if (count != sizeof(c))
- printk(UM_KERN_ERR "winch_thread : failed to read "
- "synchronization byte, err = %d\n", errno);
+ os_info("winch_thread : failed to read synchronization byte, err = %d\n",
+ errno);
while(1) {
/*
count = write(pipe_fd, &c, sizeof(c));
if (count != sizeof(c))
- printk(UM_KERN_ERR "winch_thread : write failed, "
- "err = %d\n", errno);
+ os_info("winch_thread : write failed, err = %d\n",
+ errno);
}
+
+wait_kill:
+ c = 2;
+ count = write(pipe_fd, &c, sizeof(c));
+ while (1)
+ pause();
}
static int winch_tramp(int fd, struct tty_port *port, int *fd_out,
if (fd != -1) {
err = generic_read(fd, &c, NULL);
- if (err < 0) {
+ /* A read of 2 means the winch thread failed and has warned */
+ if (err < 0 || (err == 1 && c == 2)) {
if (err != -EAGAIN) {
winch->fd = -1;
list_del(&winch->list);
os_close_file(fd);
- printk(KERN_ERR "winch_interrupt : "
- "read failed, errno = %d\n", -err);
- printk(KERN_ERR "fd %d is losing SIGWINCH "
- "support\n", winch->tty_fd);
+ if (err < 0) {
+ printk(KERN_ERR "winch_interrupt : read failed, errno = %d\n",
+ -err);
+ printk(KERN_ERR "fd %d is losing SIGWINCH support\n",
+ winch->tty_fd);
+ }
INIT_WORK(&winch->work, __free_winch);
schedule_work(&winch->work);
return IRQ_HANDLED;
return 0;
}
-static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct uml_net_private *lp = netdev_priv(dev);
unsigned long flags;
*ops = &um_pci_device_bar_ops;
*priv = &um_pci_platform_device->resptr[0];
- return 0;
+ return offset;
}
static const struct logic_iomem_region_ops um_pci_platform_ops = {
typedef struct mm_context {
struct mm_id id;
struct uml_arch_mm_context arch;
- struct page *stub_pages[2];
} mm_context_t;
extern void __switch_mm(struct mm_id * mm_idp);
struct thread_struct {
struct pt_regs regs;
struct pt_regs *segv_regs;
- int singlestep_syscall;
void *fault_addr;
jmp_buf *fault_catcher;
struct task_struct *prev_sched;
extern unsigned int do_IRQ(int irq, struct uml_pt_regs *regs);
extern void initial_thread_cb(void (*proc)(void *), void *arg);
-extern int is_syscall(unsigned long addr);
extern void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
* Are we disallowed to sleep? Used to choose between GFP_KERNEL and
* GFP_ATOMIC.
*/
-extern int __cant_sleep(void);
+extern int __uml_cant_sleep(void);
extern int get_current_pid(void);
extern int copy_from_user_proc(void *to, void *from, int size);
extern char *uml_strdup(const char *string);
extern unsigned long to_irq_stack(unsigned long *mask_out);
extern unsigned long from_irq_stack(int nested);
-extern int singlestepping(void *t);
+extern int singlestepping(void);
extern void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
extern void bus_handler(int sig, struct siginfo *si, struct uml_pt_regs *regs);
extern int __add_sigio_fd(int fd);
extern int __ignore_sigio_fd(int fd);
-/* prctl.c */
-extern int os_arch_prctl(int pid, int option, unsigned long *arg2);
-
/* tty.c */
extern int get_pty(void);
extern int ptrace_getregs(long pid, unsigned long *regs_out);
extern int ptrace_setregs(long pid, unsigned long *regs_in);
-/* syscall emulation path in ptrace */
-
-#ifndef PTRACE_SYSEMU
-#define PTRACE_SYSEMU 31
-#endif
-#ifndef PTRACE_SYSEMU_SINGLESTEP
-#define PTRACE_SYSEMU_SINGLESTEP 32
-#endif
-
-/* On architectures, that started to support PTRACE_O_TRACESYSGOOD
- * in linux 2.4, there are two different definitions of
- * PTRACE_SETOPTIONS: linux 2.4 uses 21 while linux 2.6 uses 0x4200.
- * For binary compatibility, 2.6 also supports the old "21", named
- * PTRACE_OLDSETOPTION. On these architectures, UML always must use
- * "21", to ensure the kernel runs on 2.4 and 2.6 host without
- * recompilation. So, we use PTRACE_OLDSETOPTIONS in UML.
- * We also want to be able to build the kernel on 2.4, which doesn't
- * have PTRACE_OLDSETOPTIONS. So, if it is missing, we declare
- * PTRACE_OLDSETOPTIONS to be the same as PTRACE_SETOPTIONS.
- *
- * On architectures, that start to support PTRACE_O_TRACESYSGOOD on
- * linux 2.6, PTRACE_OLDSETOPTIONS never is defined, and also isn't
- * supported by the host kernel. In that case, our trick lets us use
- * the new 0x4200 with the name PTRACE_OLDSETOPTIONS.
- */
-#ifndef PTRACE_OLDSETOPTIONS
-#define PTRACE_OLDSETOPTIONS PTRACE_SETOPTIONS
-#endif
-
-void set_using_sysemu(int value);
-int get_using_sysemu(void);
-extern int sysemu_supported;
-
-#define SELECT_PTRACE_OPERATION(sysemu_mode, singlestep_mode) \
- (((int[3][3] ) { \
- { PTRACE_SYSCALL, PTRACE_SYSCALL, PTRACE_SINGLESTEP }, \
- { PTRACE_SYSEMU, PTRACE_SYSEMU, PTRACE_SINGLESTEP }, \
- { PTRACE_SYSEMU, PTRACE_SYSEMU_SINGLESTEP, \
- PTRACE_SYSEMU_SINGLESTEP } }) \
- [sysemu_mode][singlestep_mode])
-
#endif
extern int restore_fp_registers(int pid, unsigned long *fp_regs);
extern int save_fpx_registers(int pid, unsigned long *fp_regs);
extern int restore_fpx_registers(int pid, unsigned long *fp_regs);
-extern int save_registers(int pid, struct uml_pt_regs *regs);
-extern int restore_pid_registers(int pid, struct uml_pt_regs *regs);
extern int init_pid_registers(int pid);
extern void get_safe_registers(unsigned long *regs, unsigned long *fp_regs);
extern int get_fp_registers(int pid, unsigned long *regs);
um_idle_sleep();
}
-int __cant_sleep(void) {
+int __uml_cant_sleep(void) {
return in_atomic() || irqs_disabled() || in_interrupt();
/* Is in_interrupt() really needed? */
}
late_initcall(make_proc_sysemu);
-int singlestepping(void * t)
+int singlestepping(void)
{
- struct task_struct *task = t ? t : current;
-
- if (!test_thread_flag(TIF_SINGLESTEP))
- return 0;
-
- if (task->thread.singlestep_syscall)
- return 1;
-
- return 2;
+ return test_thread_flag(TIF_SINGLESTEP);
}
/*
void user_enable_single_step(struct task_struct *child)
{
set_tsk_thread_flag(child, TIF_SINGLESTEP);
- child->thread.singlestep_syscall = 0;
#ifdef SUBARCH_SET_SINGLESTEPPING
SUBARCH_SET_SINGLESTEPPING(child, 1);
void user_disable_single_step(struct task_struct *child)
{
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
- child->thread.singlestep_syscall = 0;
#ifdef SUBARCH_SET_SINGLESTEPPING
SUBARCH_SET_SINGLESTEPPING(child, 0);
}
}
- /*
- * This closes a way to execute a system call on the host. If
- * you set a breakpoint on a system call instruction and singlestep
- * from it, the tracing thread used to PTRACE_SINGLESTEP the process
- * rather than PTRACE_SYSCALL it, allowing the system call to execute
- * on the host. The tracing thread will check this flag and
- * PTRACE_SYSCALL if necessary.
- */
- if (test_thread_flag(TIF_SINGLESTEP))
- current->thread.singlestep_syscall =
- is_syscall(PT_REGS_IP(¤t->thread.regs));
-
/*
* if there's no signal to deliver, we just put the saved sigmask
* back
* argument and comparison of the previous
* futex value with another constant.
*
- * @encoded_op: encoded operation to execute
+ * @op: operation to execute
+ * @oparg: argument to operation
+ * @oval: old value at uaddr
* @uaddr: pointer to user space address
*
* Return:
time_travel_del_event(&ne);
}
+static void time_travel_update_time_rel(unsigned long long offs)
+{
+ unsigned long flags;
+
+ /*
+ * Disable interrupts before calculating the new time so
+ * that a real timer interrupt (signal) can't happen at
+ * a bad time e.g. after we read time_travel_time but
+ * before we've completed updating the time.
+ */
+ local_irq_save(flags);
+ time_travel_update_time(time_travel_time + offs, false);
+ local_irq_restore(flags);
+}
+
void time_travel_ndelay(unsigned long nsec)
{
- time_travel_update_time(time_travel_time + nsec, false);
+ /*
+ * Not strictly needed to use _rel() version since this is
+ * only used in INFCPU/EXT modes, but it doesn't hurt and
+ * is more readable too.
+ */
+ time_travel_update_time_rel(nsec);
}
EXPORT_SYMBOL(time_travel_ndelay);
#define time_travel_time 0
#define time_travel_ext_waiting 0
-static inline void time_travel_update_time(unsigned long long ns, bool retearly)
+static inline void time_travel_update_time(unsigned long long ns, bool idle)
+{
+}
+
+static inline void time_travel_update_time_rel(unsigned long long offs)
{
}
*/
if (!irqs_disabled() && !in_interrupt() && !in_softirq() &&
!time_travel_ext_waiting)
- time_travel_update_time(time_travel_time +
- TIMER_MULTIPLIER,
- false);
+ time_travel_update_time_rel(TIMER_MULTIPLIER);
return time_travel_time / TIMER_MULTIPLIER;
}
unsigned long stack, sp;
int pid, fds[2], ret, n;
- stack = alloc_stack(0, __cant_sleep());
+ stack = alloc_stack(0, __uml_cant_sleep());
if (stack == 0)
return -ENOMEM;
data.pre_data = pre_data;
data.argv = argv;
data.fd = fds[1];
- data.buf = __cant_sleep() ? uml_kmalloc(PATH_MAX, UM_GFP_ATOMIC) :
+ data.buf = __uml_cant_sleep() ? uml_kmalloc(PATH_MAX, UM_GFP_ATOMIC) :
uml_kmalloc(PATH_MAX, UM_GFP_KERNEL);
pid = clone(helper_child, (void *) sp, CLONE_VM, &data);
if (pid < 0) {
unsigned long stack, sp;
int pid, status, err;
- stack = alloc_stack(0, __cant_sleep());
+ stack = alloc_stack(0, __uml_cant_sleep());
if (stack == 0)
return -ENOMEM;
#include <sysdep/ptrace_user.h>
#include <registers.h>
-int save_registers(int pid, struct uml_pt_regs *regs)
-{
- int err;
-
- err = ptrace(PTRACE_GETREGS, pid, 0, regs->gp);
- if (err < 0)
- return -errno;
- return 0;
-}
-
-int restore_pid_registers(int pid, struct uml_pt_regs *regs)
-{
- int err;
-
- err = ptrace(PTRACE_SETREGS, pid, 0, regs->gp);
- if (err < 0)
- return -errno;
- return 0;
-}
-
/* This is set once at boot time and not changed thereafter */
static unsigned long exec_regs[MAX_REG_NR];
segv(regs->faultinfo, 0, 1, NULL);
}
-/*
- * To use the same value of using_sysemu as the caller, ask it that value
- * (in local_using_sysemu
- */
-static void handle_trap(int pid, struct uml_pt_regs *regs,
- int local_using_sysemu)
+static void handle_trap(int pid, struct uml_pt_regs *regs)
{
- int err, status;
-
if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END))
fatal_sigsegv();
- if (!local_using_sysemu)
- {
- err = ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET,
- __NR_getpid);
- if (err < 0) {
- printk(UM_KERN_ERR "%s - nullifying syscall failed, errno = %d\n",
- __func__, errno);
- fatal_sigsegv();
- }
-
- err = ptrace(PTRACE_SYSCALL, pid, 0, 0);
- if (err < 0) {
- printk(UM_KERN_ERR "%s - continuing to end of syscall failed, errno = %d\n",
- __func__, errno);
- fatal_sigsegv();
- }
-
- CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL));
- if ((err < 0) || !WIFSTOPPED(status) ||
- (WSTOPSIG(status) != SIGTRAP + 0x80)) {
- err = ptrace_dump_regs(pid);
- if (err)
- printk(UM_KERN_ERR "Failed to get registers from process, errno = %d\n",
- -err);
- printk(UM_KERN_ERR "%s - failed to wait at end of syscall, errno = %d, status = %d\n",
- __func__, errno, status);
- fatal_sigsegv();
- }
- }
-
handle_syscall(regs);
}
/**
* userspace_tramp() - userspace trampoline
- * @stack: pointer to the new userspace stack page, can be NULL, if? FIXME:
+ * @stack: pointer to the new userspace stack page
*
* The userspace trampoline is used to setup a new userspace process in start_userspace() after it was clone()'ed.
* This function will run on a temporary stack page.
*/
static int userspace_tramp(void *stack)
{
+ struct sigaction sa;
void *addr;
int fd;
unsigned long long offset;
+ unsigned long segv_handler = STUB_CODE +
+ (unsigned long) stub_segv_handler -
+ (unsigned long) __syscall_stub_start;
ptrace(PTRACE_TRACEME, 0, 0, 0);
addr = mmap64((void *) STUB_CODE, UM_KERN_PAGE_SIZE,
PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset);
if (addr == MAP_FAILED) {
- printk(UM_KERN_ERR "mapping mmap stub at 0x%lx failed, errno = %d\n",
- STUB_CODE, errno);
+ os_info("mapping mmap stub at 0x%lx failed, errno = %d\n",
+ STUB_CODE, errno);
exit(1);
}
- if (stack != NULL) {
- fd = phys_mapping(uml_to_phys(stack), &offset);
- addr = mmap((void *) STUB_DATA,
- STUB_DATA_PAGES * UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
- MAP_FIXED | MAP_SHARED, fd, offset);
- if (addr == MAP_FAILED) {
- printk(UM_KERN_ERR "mapping segfault stack at 0x%lx failed, errno = %d\n",
- STUB_DATA, errno);
- exit(1);
- }
+ fd = phys_mapping(uml_to_phys(stack), &offset);
+ addr = mmap((void *) STUB_DATA,
+ STUB_DATA_PAGES * UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
+ MAP_FIXED | MAP_SHARED, fd, offset);
+ if (addr == MAP_FAILED) {
+ os_info("mapping segfault stack at 0x%lx failed, errno = %d\n",
+ STUB_DATA, errno);
+ exit(1);
}
- if (stack != NULL) {
- struct sigaction sa;
-
- unsigned long v = STUB_CODE +
- (unsigned long) stub_segv_handler -
- (unsigned long) __syscall_stub_start;
-
- set_sigstack((void *) STUB_DATA, STUB_DATA_PAGES * UM_KERN_PAGE_SIZE);
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = SA_ONSTACK | SA_NODEFER | SA_SIGINFO;
- sa.sa_sigaction = (void *) v;
- sa.sa_restorer = NULL;
- if (sigaction(SIGSEGV, &sa, NULL) < 0) {
- printk(UM_KERN_ERR "%s - setting SIGSEGV handler failed - errno = %d\n",
- __func__, errno);
- exit(1);
- }
+
+ set_sigstack((void *) STUB_DATA, STUB_DATA_PAGES * UM_KERN_PAGE_SIZE);
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = SA_ONSTACK | SA_NODEFER | SA_SIGINFO;
+ sa.sa_sigaction = (void *) segv_handler;
+ sa.sa_restorer = NULL;
+ if (sigaction(SIGSEGV, &sa, NULL) < 0) {
+ os_info("%s - setting SIGSEGV handler failed - errno = %d\n",
+ __func__, errno);
+ exit(1);
}
kill(os_getpid(), SIGSTOP);
/**
* start_userspace() - prepare a new userspace process
- * @stub_stack: pointer to the stub stack. Can be NULL, if? FIXME:
+ * @stub_stack: pointer to the stub stack.
*
* Setups a new temporary stack page that is used while userspace_tramp() runs
* Clones the kernel process into a new userspace process, with FDs only.
goto out_kill;
}
- if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
+ if (ptrace(PTRACE_SETOPTIONS, pid, NULL,
(void *) PTRACE_O_TRACESYSGOOD) < 0) {
err = -errno;
- printk(UM_KERN_ERR "%s : PTRACE_OLDSETOPTIONS failed, errno = %d\n",
+ printk(UM_KERN_ERR "%s : PTRACE_SETOPTIONS failed, errno = %d\n",
__func__, errno);
goto out_kill;
}
void userspace(struct uml_pt_regs *regs, unsigned long *aux_fp_regs)
{
int err, status, op, pid = userspace_pid[0];
- /* To prevent races if using_sysemu changes under us.*/
- int local_using_sysemu;
siginfo_t si;
/* Handle any immediate reschedules or signals */
fatal_sigsegv();
}
- /* Now we set local_using_sysemu to be used for one loop */
- local_using_sysemu = get_using_sysemu();
-
- op = SELECT_PTRACE_OPERATION(local_using_sysemu,
- singlestepping(NULL));
+ if (singlestepping())
+ op = PTRACE_SYSEMU_SINGLESTEP;
+ else
+ op = PTRACE_SYSEMU;
if (ptrace(op, pid, 0, 0)) {
printk(UM_KERN_ERR "%s - ptrace continue failed, op = %d, errno = %d\n",
else handle_segv(pid, regs, aux_fp_regs);
break;
case SIGTRAP + 0x80:
- handle_trap(pid, regs, local_using_sysemu);
+ handle_trap(pid, regs);
break;
case SIGTRAP:
relay_signal(SIGTRAP, (struct siginfo *)&si, regs);
goto out_kill;
}
- if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
+ if (ptrace(PTRACE_SETOPTIONS, pid, NULL,
(void *)PTRACE_O_TRACESYSGOOD) < 0) {
err = -errno;
- printk(UM_KERN_ERR "%s : PTRACE_OLDSETOPTIONS failed, errno = %d\n",
+ printk(UM_KERN_ERR "%s : PTRACE_SETOPTIONS failed, errno = %d\n",
__func__, errno);
goto out_kill;
}
return pid;
}
-/* When testing for SYSEMU support, if it is one of the broken versions, we
- * must just avoid using sysemu, not panic, but only if SYSEMU features are
- * broken.
- * So only for SYSEMU features we test mustpanic, while normal host features
- * must work anyway!
- */
-static int stop_ptraced_child(int pid, int exitcode, int mustexit)
+static void stop_ptraced_child(int pid, int exitcode)
{
- int status, n, ret = 0;
+ int status, n;
+
+ if (ptrace(PTRACE_CONT, pid, 0, 0) < 0)
+ fatal_perror("stop_ptraced_child : ptrace failed");
- if (ptrace(PTRACE_CONT, pid, 0, 0) < 0) {
- perror("stop_ptraced_child : ptrace failed");
- return -1;
- }
CATCH_EINTR(n = waitpid(pid, &status, 0));
if (!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
int exit_with = WEXITSTATUS(status);
- if (exit_with == 2)
- non_fatal("check_ptrace : child exited with status 2. "
- "\nDisabling SYSEMU support.\n");
- non_fatal("check_ptrace : child exited with exitcode %d, while "
- "expecting %d; status 0x%x\n", exit_with,
- exitcode, status);
- if (mustexit)
- exit(1);
- ret = -1;
+ fatal("stop_ptraced_child : child exited with exitcode %d, "
+ "while expecting %d; status 0x%x\n", exit_with,
+ exitcode, status);
}
-
- return ret;
-}
-
-/* Changed only during early boot */
-static int force_sysemu_disabled = 0;
-
-static int __init nosysemu_cmd_param(char *str, int* add)
-{
- force_sysemu_disabled = 1;
- return 0;
}
-__uml_setup("nosysemu", nosysemu_cmd_param,
-"nosysemu\n"
-" Turns off syscall emulation patch for ptrace (SYSEMU).\n"
-" SYSEMU is a performance-patch introduced by Laurent Vivier. It changes\n"
-" behaviour of ptrace() and helps reduce host context switch rates.\n"
-" To make it work, you need a kernel patch for your host, too.\n"
-" See http://perso.wanadoo.fr/laurent.vivier/UML/ for further \n"
-" information.\n\n");
-
static void __init check_sysemu(void)
{
- unsigned long regs[MAX_REG_NR];
int pid, n, status, count=0;
- os_info("Checking syscall emulation patch for ptrace...");
- sysemu_supported = 0;
- pid = start_ptraced_child();
-
- if (ptrace(PTRACE_SYSEMU, pid, 0, 0) < 0)
- goto fail;
-
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- if (n < 0)
- fatal_perror("check_sysemu : wait failed");
- if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- fatal("check_sysemu : expected SIGTRAP, got status = %d\n",
- status);
-
- if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
- fatal_perror("check_sysemu : PTRACE_GETREGS failed");
- if (PT_SYSCALL_NR(regs) != __NR_getpid) {
- non_fatal("check_sysemu got system call number %d, "
- "expected %d...", PT_SYSCALL_NR(regs), __NR_getpid);
- goto fail;
- }
-
- n = ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_RET_OFFSET, os_getpid());
- if (n < 0) {
- non_fatal("check_sysemu : failed to modify system call "
- "return");
- goto fail;
- }
-
- if (stop_ptraced_child(pid, 0, 0) < 0)
- goto fail_stopped;
-
- sysemu_supported = 1;
- os_info("OK\n");
- set_using_sysemu(!force_sysemu_disabled);
-
- os_info("Checking advanced syscall emulation patch for ptrace...");
+ os_info("Checking syscall emulation for ptrace...");
pid = start_ptraced_child();
- if ((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
+ if ((ptrace(PTRACE_SETOPTIONS, pid, 0,
(void *) PTRACE_O_TRACESYSGOOD) < 0))
- fatal_perror("check_sysemu: PTRACE_OLDSETOPTIONS failed");
+ fatal_perror("check_sysemu: PTRACE_SETOPTIONS failed");
while (1) {
count++;
goto fail;
}
}
- if (stop_ptraced_child(pid, 0, 0) < 0)
- goto fail_stopped;
+ stop_ptraced_child(pid, 0);
- sysemu_supported = 2;
os_info("OK\n");
- if (!force_sysemu_disabled)
- set_using_sysemu(sysemu_supported);
return;
fail:
- stop_ptraced_child(pid, 1, 0);
-fail_stopped:
- non_fatal("missing\n");
+ stop_ptraced_child(pid, 1);
+ fatal("missing\n");
}
static void __init check_ptrace(void)
os_info("Checking that ptrace can change system call numbers...");
pid = start_ptraced_child();
- if ((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
+ if ((ptrace(PTRACE_SETOPTIONS, pid, 0,
(void *) PTRACE_O_TRACESYSGOOD) < 0))
- fatal_perror("check_ptrace: PTRACE_OLDSETOPTIONS failed");
+ fatal_perror("check_ptrace: PTRACE_SETOPTIONS failed");
while (1) {
if (ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
break;
}
}
- stop_ptraced_child(pid, 0, 1);
+ stop_ptraced_child(pid, 0);
os_info("OK\n");
check_sysemu();
}
pid = start_ptraced_child();
if (init_pid_registers(pid))
fatal("Failed to initialize default registers");
- stop_ptraced_child(pid, 1, 1);
+ stop_ptraced_child(pid, 1);
}
int __init parse_iomem(char *str, int *add)
"quiet\n"
" Turns off information messages during boot.\n\n");
+/*
+ * The os_info/os_warn functions will be called by helper threads. These
+ * have a very limited stack size and using the libc formatting functions
+ * may overflow the stack.
+ * So pull in the kernel vscnprintf and use that instead with a fixed
+ * on-stack buffer.
+ */
+int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
+
void os_info(const char *fmt, ...)
{
+ char buf[256];
va_list list;
+ int len;
if (quiet_info)
return;
va_start(list, fmt);
- vfprintf(stderr, fmt, list);
+ len = vscnprintf(buf, sizeof(buf), fmt, list);
+ fwrite(buf, len, 1, stderr);
va_end(list);
}
void os_warn(const char *fmt, ...)
{
+ char buf[256];
va_list list;
+ int len;
va_start(list, fmt);
- vfprintf(stderr, fmt, list);
+ len = vscnprintf(buf, sizeof(buf), fmt, list);
+ fwrite(buf, len, 1, stderr);
va_end(list);
}
(pr_reg)[18] = (_regs)->regs.gp[18]; \
(pr_reg)[19] = (_regs)->regs.gp[19]; \
(pr_reg)[20] = (_regs)->regs.gp[20]; \
- (pr_reg)[21] = current->thread.arch.fs; \
- (pr_reg)[22] = 0; \
+ (pr_reg)[21] = (_regs)->regs.gp[21]; \
+ (pr_reg)[22] = (_regs)->regs.gp[22]; \
(pr_reg)[23] = 0; \
(pr_reg)[24] = 0; \
(pr_reg)[25] = 0; \
struct arch_thread {
unsigned long debugregs[8];
int debugregs_seq;
- unsigned long fs;
struct faultinfo faultinfo;
};
#define INIT_ARCH_THREAD { .debugregs = { [ 0 ... 7 ] = 0 }, \
.debugregs_seq = 0, \
- .fs = 0, \
.faultinfo = { 0, 0, 0 } }
#define STACKSLOTS_PER_LINE 4
static inline void arch_copy_thread(struct arch_thread *from,
struct arch_thread *to)
{
- to->fs = from->fs;
}
#define current_sp() ({ void *sp; __asm__("movq %%rsp, %0" : "=r" (sp) : ); sp; })
obj-y = registers.o task_size.o mcontext.o
obj-$(CONFIG_X86_32) += tls.o
-obj-$(CONFIG_64BIT) += prctl.o
USER_OBJS := $(obj-y)
+++ /dev/null
-/*
- * Copyright (C) 2007 Jeff Dike (jdike@{addtoit.com,linux.intel.com})
- * Licensed under the GPL
- */
-
-#include <sys/ptrace.h>
-#include <asm/ptrace.h>
-
-int os_arch_prctl(int pid, int option, unsigned long *arg2)
-{
- return ptrace(PTRACE_ARCH_PRCTL, pid, (unsigned long) arg2, option);
-}
printk(KERN_WARNING "arch_switch_tls failed, errno = EINVAL\n");
}
-int is_syscall(unsigned long addr)
-{
- unsigned short instr;
- int n;
-
- n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
- if (n) {
- /* access_process_vm() grants access to vsyscall and stub,
- * while copy_from_user doesn't. Maybe access_process_vm is
- * slow, but that doesn't matter, since it will be called only
- * in case of singlestepping, if copy_from_user failed.
- */
- n = access_process_vm(current, addr, &instr, sizeof(instr),
- FOLL_FORCE);
- if (n != sizeof(instr)) {
- printk(KERN_ERR "is_syscall : failed to read "
- "instruction from 0x%lx\n", addr);
- return 1;
- }
- }
- /* int 0x80 or sysenter */
- return (instr == 0x80cd) || (instr == 0x340f);
-}
-
/* determines which flags the user has access to. */
/* 1 = access 0 = no access */
#define FLAG_MASK 0x00044dd5
return put_user(tmp, (unsigned long *) data);
}
-/* XXX Mostly copied from sys-i386 */
-int is_syscall(unsigned long addr)
-{
- unsigned short instr;
- int n;
-
- n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
- if (n) {
- /*
- * access_process_vm() grants access to vsyscall and stub,
- * while copy_from_user doesn't. Maybe access_process_vm is
- * slow, but that doesn't matter, since it will be called only
- * in case of singlestepping, if copy_from_user failed.
- */
- n = access_process_vm(current, addr, &instr, sizeof(instr),
- FOLL_FORCE);
- if (n != sizeof(instr)) {
- printk("is_syscall : failed to read instruction from "
- "0x%lx\n", addr);
- return 1;
- }
- }
- /* sysenter */
- return instr == 0x050f;
-}
-
static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
#define MAX_FP_NR HOST_FPX_SIZE
-void set_using_sysemu(int value);
-int get_using_sysemu(void);
-extern int sysemu_supported;
-
#define UPT_SYSCALL_ARG1(r) UPT_BX(r)
#define UPT_SYSCALL_ARG2(r) UPT_CX(r)
#define UPT_SYSCALL_ARG3(r) UPT_DX(r)
#define FP_SIZE ((HOST_FPX_SIZE > HOST_FP_SIZE) ? HOST_FPX_SIZE : HOST_FP_SIZE)
#else
#define FP_SIZE HOST_FP_SIZE
+#endif
/*
- * x86_64 FC3 doesn't define this in /usr/include/linux/ptrace.h even though
- * it's defined in the kernel's include/linux/ptrace.h. Additionally, use the
- * 2.4 name and value for 2.4 host compatibility.
+ * glibc before 2.27 does not include PTRACE_SYSEMU_SINGLESTEP in its enum,
+ * ensure we have a definition by (re-)defining it here.
*/
-#ifndef PTRACE_OLDSETOPTIONS
-#define PTRACE_OLDSETOPTIONS 21
-#endif
-
+#ifndef PTRACE_SYSEMU_SINGLESTEP
+#define PTRACE_SYSEMU_SINGLESTEP 32
#endif
#define STUB_MMAP_NR __NR_mmap2
#define MMAP_OFFSET(o) ((o) >> UM_KERN_PAGE_SHIFT)
-static inline long stub_syscall0(long syscall)
+static __always_inline long stub_syscall0(long syscall)
{
long ret;
- __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall));
+ __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall)
+ : "memory");
return ret;
}
-static inline long stub_syscall1(long syscall, long arg1)
+static __always_inline long stub_syscall1(long syscall, long arg1)
{
long ret;
- __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1));
+ __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1)
+ : "memory");
return ret;
}
-static inline long stub_syscall2(long syscall, long arg1, long arg2)
+static __always_inline long stub_syscall2(long syscall, long arg1, long arg2)
{
long ret;
__asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
- "c" (arg2));
+ "c" (arg2)
+ : "memory");
return ret;
}
-static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
+static __always_inline long stub_syscall3(long syscall, long arg1, long arg2,
+ long arg3)
{
long ret;
__asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
- "c" (arg2), "d" (arg3));
+ "c" (arg2), "d" (arg3)
+ : "memory");
return ret;
}
-static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
- long arg4)
+static __always_inline long stub_syscall4(long syscall, long arg1, long arg2,
+ long arg3, long arg4)
{
long ret;
__asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
- "c" (arg2), "d" (arg3), "S" (arg4));
+ "c" (arg2), "d" (arg3), "S" (arg4)
+ : "memory");
return ret;
}
-static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3,
- long arg4, long arg5)
+static __always_inline long stub_syscall5(long syscall, long arg1, long arg2,
+ long arg3, long arg4, long arg5)
{
long ret;
__asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
- "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5));
+ "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5)
+ : "memory");
return ret;
}
-static inline void trap_myself(void)
+static __always_inline void trap_myself(void)
{
__asm("int3");
}
-static inline void remap_stack_and_trap(void)
+static __always_inline void remap_stack_and_trap(void)
{
__asm__ volatile (
"movl %%esp,%%ebx ;"
#define __syscall_clobber "r11","rcx","memory"
#define __syscall "syscall"
-static inline long stub_syscall0(long syscall)
+static __always_inline long stub_syscall0(long syscall)
{
long ret;
return ret;
}
-static inline long stub_syscall2(long syscall, long arg1, long arg2)
+static __always_inline long stub_syscall2(long syscall, long arg1, long arg2)
{
long ret;
return ret;
}
-static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
+static __always_inline long stub_syscall3(long syscall, long arg1, long arg2,
+ long arg3)
{
long ret;
return ret;
}
-static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
+static __always_inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
long arg4)
{
long ret;
return ret;
}
-static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3,
- long arg4, long arg5)
+static __always_inline long stub_syscall5(long syscall, long arg1, long arg2,
+ long arg3, long arg4, long arg5)
{
long ret;
return ret;
}
-static inline void trap_myself(void)
+static __always_inline void trap_myself(void)
{
__asm("int3");
}
-static inline void remap_stack_and_trap(void)
+static __always_inline void remap_stack_and_trap(void)
{
__asm__ volatile (
"movq %0,%%rax ;"
long arch_prctl(struct task_struct *task, int option,
unsigned long __user *arg2)
{
- unsigned long *ptr = arg2, tmp;
- long ret;
- int pid = task->mm->context.id.u.pid;
-
- /*
- * With ARCH_SET_FS (and ARCH_SET_GS is treated similarly to
- * be safe), we need to call arch_prctl on the host because
- * setting %fs may result in something else happening (like a
- * GDT or thread.fs being set instead). So, we let the host
- * fiddle the registers and thread struct and restore the
- * registers afterwards.
- *
- * So, the saved registers are stored to the process (this
- * needed because a stub may have been the last thing to run),
- * arch_prctl is run on the host, then the registers are read
- * back.
- */
- switch (option) {
- case ARCH_SET_FS:
- case ARCH_SET_GS:
- ret = restore_pid_registers(pid, ¤t->thread.regs.regs);
- if (ret)
- return ret;
- break;
- case ARCH_GET_FS:
- case ARCH_GET_GS:
- /*
- * With these two, we read to a local pointer and
- * put_user it to the userspace pointer that we were
- * given. If addr isn't valid (because it hasn't been
- * faulted in or is just bogus), we want put_user to
- * fault it in (or return -EFAULT) instead of having
- * the host return -EFAULT.
- */
- ptr = &tmp;
- }
-
- ret = os_arch_prctl(pid, option, ptr);
- if (ret)
- return ret;
+ long ret = -EINVAL;
switch (option) {
case ARCH_SET_FS:
- current->thread.arch.fs = (unsigned long) ptr;
- ret = save_registers(pid, ¤t->thread.regs.regs);
+ current->thread.regs.regs.gp[FS_BASE / sizeof(unsigned long)] =
+ (unsigned long) arg2;
+ ret = 0;
break;
case ARCH_SET_GS:
- ret = save_registers(pid, ¤t->thread.regs.regs);
+ current->thread.regs.regs.gp[GS_BASE / sizeof(unsigned long)] =
+ (unsigned long) arg2;
+ ret = 0;
break;
case ARCH_GET_FS:
- ret = put_user(tmp, arg2);
+ ret = put_user(current->thread.regs.regs.gp[FS_BASE / sizeof(unsigned long)], arg2);
break;
case ARCH_GET_GS:
- ret = put_user(tmp, arg2);
+ ret = put_user(current->thread.regs.regs.gp[GS_BASE / sizeof(unsigned long)], arg2);
break;
}
void arch_switch_to(struct task_struct *to)
{
- if ((to->thread.arch.fs == 0) || (to->mm == NULL))
- return;
-
- arch_prctl(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
+ /*
+ * Nothing needs to be done on x86_64.
+ * The FS_BASE/GS_BASE registers are saved in the ptrace register set.
+ */
}
SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
* If CLONE_SETTLS is set, we need to save the thread id
* so it can be set during context switches.
*/
- t->thread.arch.fs = tls;
+ t->thread.regs.regs.gp[FS_BASE / sizeof(unsigned long)] = tls;
return 0;
}
projects / thirdparty / linux.git / commitdiff
