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-rw-r--r--arch/um/Makefile-skas5
-rw-r--r--arch/um/drivers/chan_user.c42
-rw-r--r--arch/um/drivers/line.c13
-rw-r--r--arch/um/drivers/net_kern.c2
-rw-r--r--arch/um/drivers/virt-pci.c2
-rw-r--r--arch/um/include/asm/mmu.h1
-rw-r--r--arch/um/include/asm/processor-generic.h1
-rw-r--r--arch/um/include/shared/kern_util.h5
-rw-r--r--arch/um/include/shared/os.h3
-rw-r--r--arch/um/include/shared/ptrace_user.h41
-rw-r--r--arch/um/include/shared/registers.h2
-rw-r--r--arch/um/kernel/process.c14
-rw-r--r--arch/um/kernel/ptrace.c2
-rw-r--r--arch/um/kernel/signal.c12
-rw-r--r--arch/um/kernel/skas/uaccess.c4
-rw-r--r--arch/um/kernel/time.c32
-rw-r--r--arch/um/os-Linux/helper.c6
-rw-r--r--arch/um/os-Linux/registers.c20
-rw-r--r--arch/um/os-Linux/skas/process.c117
-rw-r--r--arch/um/os-Linux/start_up.c111
-rw-r--r--arch/um/os-Linux/util.c19
21 files changed, 148 insertions, 306 deletions
diff --git a/arch/um/Makefile-skas b/arch/um/Makefile-skas
index ac35de5316a6..67323b028999 100644
--- a/arch/um/Makefile-skas
+++ b/arch/um/Makefile-skas
@@ -4,7 +4,12 @@
#
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)
diff --git a/arch/um/drivers/chan_user.c b/arch/um/drivers/chan_user.c
index 25727ed648b7..ed7cc830b3e7 100644
--- a/arch/um/drivers/chan_user.c
+++ b/arch/um/drivers/chan_user.c
@@ -141,7 +141,7 @@ struct winch_data {
int pipe_fd;
};
-static int winch_thread(void *arg)
+static __noreturn int winch_thread(void *arg)
{
struct winch_data *data = arg;
sigset_t sigs;
@@ -153,8 +153,8 @@ static int winch_thread(void *arg)
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
@@ -166,29 +166,29 @@ static int winch_thread(void *arg)
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;
}
/*
@@ -199,8 +199,8 @@ static int winch_thread(void *arg)
*/
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) {
/*
@@ -211,9 +211,15 @@ static int winch_thread(void *arg)
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,
diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index b98545f3edb5..449d320c3f55 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -629,15 +629,18 @@ static irqreturn_t winch_interrupt(int irq, void *data)
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;
diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
index 3d7836c46507..cabcc501b448 100644
--- a/arch/um/drivers/net_kern.c
+++ b/arch/um/drivers/net_kern.c
@@ -204,7 +204,7 @@ static int uml_net_close(struct net_device *dev)
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;
diff --git a/arch/um/drivers/virt-pci.c b/arch/um/drivers/virt-pci.c
index ffe2ee8a0246..97a37c062997 100644
--- a/arch/um/drivers/virt-pci.c
+++ b/arch/um/drivers/virt-pci.c
@@ -971,7 +971,7 @@ static long um_pci_map_platform(unsigned long offset, size_t size,
*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 = {
diff --git a/arch/um/include/asm/mmu.h b/arch/um/include/asm/mmu.h
index 5b072aba5b65..a7555e43ed14 100644
--- a/arch/um/include/asm/mmu.h
+++ b/arch/um/include/asm/mmu.h
@@ -12,7 +12,6 @@
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);
diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h
index 7414154b8e9a..6c3779541845 100644
--- a/arch/um/include/asm/processor-generic.h
+++ b/arch/um/include/asm/processor-generic.h
@@ -22,7 +22,6 @@ struct mm_struct;
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;
diff --git a/arch/um/include/shared/kern_util.h b/arch/um/include/shared/kern_util.h
index d8b8b4f07e42..789b83013f35 100644
--- a/arch/um/include/shared/kern_util.h
+++ b/arch/um/include/shared/kern_util.h
@@ -34,7 +34,6 @@ extern int handle_page_fault(unsigned long address, unsigned long ip,
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);
@@ -50,7 +49,7 @@ extern void do_uml_exitcalls(void);
* 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);
@@ -58,7 +57,7 @@ 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);
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 0df646c6651e..aff8906304ea 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -323,9 +323,6 @@ extern void sigio_broken(int fd);
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);
diff --git a/arch/um/include/shared/ptrace_user.h b/arch/um/include/shared/ptrace_user.h
index 95455e8996e7..8a705d8f96ce 100644
--- a/arch/um/include/shared/ptrace_user.h
+++ b/arch/um/include/shared/ptrace_user.h
@@ -12,45 +12,4 @@
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
diff --git a/arch/um/include/shared/registers.h b/arch/um/include/shared/registers.h
index 2f9c3ce5b45e..a0450326521c 100644
--- a/arch/um/include/shared/registers.h
+++ b/arch/um/include/shared/registers.h
@@ -14,8 +14,6 @@ extern int save_fp_registers(int pid, unsigned long *fp_regs);
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);
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 106b7da2f8d6..ab95648e93e1 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -220,7 +220,7 @@ void arch_cpu_idle(void)
um_idle_sleep();
}
-int __cant_sleep(void) {
+int __uml_cant_sleep(void) {
return in_atomic() || irqs_disabled() || in_interrupt();
/* Is in_interrupt() really needed? */
}
@@ -332,17 +332,9 @@ int __init make_proc_sysemu(void)
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);
}
/*
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
index 5154b27de580..6600a2782796 100644
--- a/arch/um/kernel/ptrace.c
+++ b/arch/um/kernel/ptrace.c
@@ -12,7 +12,6 @@
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);
@@ -22,7 +21,6 @@ void user_enable_single_step(struct task_struct *child)
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);
diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c
index ae4658f576ab..a56b44522766 100644
--- a/arch/um/kernel/signal.c
+++ b/arch/um/kernel/signal.c
@@ -121,18 +121,6 @@ void do_signal(struct pt_regs *regs)
}
/*
- * 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(&current->thread.regs));
-
- /*
* if there's no signal to deliver, we just put the saved sigmask
* back
*/
diff --git a/arch/um/kernel/skas/uaccess.c b/arch/um/kernel/skas/uaccess.c
index aaee96f07172..198269e384c4 100644
--- a/arch/um/kernel/skas/uaccess.c
+++ b/arch/um/kernel/skas/uaccess.c
@@ -236,7 +236,9 @@ EXPORT_SYMBOL(strnlen_user);
* 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:
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index fddd1dec27e6..3e270da6b6f6 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -432,9 +432,29 @@ static void time_travel_update_time(unsigned long long next, bool idle)
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);
@@ -568,7 +588,11 @@ static void time_travel_set_start(void)
#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)
{
}
@@ -720,9 +744,7 @@ static u64 timer_read(struct clocksource *cs)
*/
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;
}
diff --git a/arch/um/os-Linux/helper.c b/arch/um/os-Linux/helper.c
index b459745f52e2..3cb8ac63be6e 100644
--- a/arch/um/os-Linux/helper.c
+++ b/arch/um/os-Linux/helper.c
@@ -46,7 +46,7 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv)
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;
@@ -70,7 +70,7 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv)
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) {
@@ -121,7 +121,7 @@ int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags,
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;
diff --git a/arch/um/os-Linux/registers.c b/arch/um/os-Linux/registers.c
index b123955be7ac..bd80b921add0 100644
--- a/arch/um/os-Linux/registers.c
+++ b/arch/um/os-Linux/registers.c
@@ -11,26 +11,6 @@
#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];
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 9464833e741a..1f5c3f2523d1 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -177,48 +177,11 @@ static void handle_segv(int pid, struct uml_pt_regs *regs, unsigned long *aux_fp
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);
}
@@ -226,7 +189,7 @@ extern char __syscall_stub_start[];
/**
* 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.
@@ -241,9 +204,13 @@ extern char __syscall_stub_start[];
*/
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);
@@ -254,39 +221,30 @@ static int userspace_tramp(void *stack)
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);
@@ -298,7 +256,7 @@ int kill_userspace_mm[NR_CPUS];
/**
* 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.
@@ -355,10 +313,10 @@ int start_userspace(unsigned long stub_stack)
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;
}
@@ -380,8 +338,6 @@ int start_userspace(unsigned long stub_stack)
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 */
@@ -411,11 +367,10 @@ void userspace(struct uml_pt_regs *regs, unsigned long *aux_fp_regs)
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",
@@ -474,7 +429,7 @@ void userspace(struct uml_pt_regs *regs, unsigned long *aux_fp_regs)
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);
@@ -597,10 +552,10 @@ int copy_context_skas0(unsigned long new_stack, int pid)
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;
}
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index e3ee4db58b40..8b0e98ab842c 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -112,102 +112,32 @@ static int start_ptraced_child(void)
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++;
@@ -240,20 +170,15 @@ static void __init check_sysemu(void)
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)
@@ -263,9 +188,9 @@ 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)
@@ -291,7 +216,7 @@ static void __init check_ptrace(void)
break;
}
}
- stop_ptraced_child(pid, 0, 1);
+ stop_ptraced_child(pid, 0);
os_info("OK\n");
check_sysemu();
}
@@ -370,7 +295,7 @@ void __init os_early_checks(void)
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)
diff --git a/arch/um/os-Linux/util.c b/arch/um/os-Linux/util.c
index fc0f2a9dee5a..1dca4ffbd572 100644
--- a/arch/um/os-Linux/util.c
+++ b/arch/um/os-Linux/util.c
@@ -173,23 +173,38 @@ __uml_setup("quiet", quiet_cmd_param,
"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);
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-01 11:29:50 +0300