diff options
34 files changed, 212 insertions, 459 deletions
diff --git a/Documentation/dev-tools/kunit/running_tips.rst b/Documentation/dev-tools/kunit/running_tips.rst index 024e9ad1d1e9..bd689db6fdd2 100644 --- a/Documentation/dev-tools/kunit/running_tips.rst +++ b/Documentation/dev-tools/kunit/running_tips.rst @@ -139,6 +139,17 @@ If your installed version of gcc doesn't work, you can tweak the steps: $ ./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 ====================== 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(¤t->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); } diff --git a/arch/x86/um/asm/elf.h b/arch/x86/um/asm/elf.h index 6523eb7c3bd1..6052200fe925 100644 --- a/arch/x86/um/asm/elf.h +++ b/arch/x86/um/asm/elf.h @@ -168,8 +168,8 @@ do { \ (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; \ diff --git a/arch/x86/um/asm/processor_64.h b/arch/x86/um/asm/processor_64.h index 1ef9c21877bc..f90159508936 100644 --- a/arch/x86/um/asm/processor_64.h +++ b/arch/x86/um/asm/processor_64.h @@ -10,13 +10,11 @@ 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 @@ -28,7 +26,6 @@ static inline void arch_flush_thread(struct arch_thread *thread) 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; }) diff --git a/arch/x86/um/os-Linux/Makefile b/arch/x86/um/os-Linux/Makefile index ae169125d03f..5249bbc30dcd 100644 --- a/arch/x86/um/os-Linux/Makefile +++ b/arch/x86/um/os-Linux/Makefile @@ -6,7 +6,6 @@ obj-y = registers.o task_size.o mcontext.o obj-$(CONFIG_X86_32) += tls.o -obj-$(CONFIG_64BIT) += prctl.o USER_OBJS := $(obj-y) diff --git a/arch/x86/um/os-Linux/prctl.c b/arch/x86/um/os-Linux/prctl.c deleted file mode 100644 index 8431e87ac333..000000000000 --- a/arch/x86/um/os-Linux/prctl.c +++ /dev/null @@ -1,12 +0,0 @@ -/* - * 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); -} diff --git a/arch/x86/um/ptrace_32.c b/arch/x86/um/ptrace_32.c index 0bc4b73a9cde..7f1abde2c84b 100644 --- a/arch/x86/um/ptrace_32.c +++ b/arch/x86/um/ptrace_32.c @@ -25,30 +25,6 @@ void arch_switch_to(struct task_struct *to) 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 diff --git a/arch/x86/um/ptrace_64.c b/arch/x86/um/ptrace_64.c index 289d0159b041..aa68d83d3f44 100644 --- a/arch/x86/um/ptrace_64.c +++ b/arch/x86/um/ptrace_64.c @@ -188,32 +188,6 @@ int peek_user(struct task_struct *child, long addr, long data) 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; diff --git a/arch/x86/um/shared/sysdep/ptrace_32.h b/arch/x86/um/shared/sysdep/ptrace_32.h index db8478a83a09..0c4989842fbe 100644 --- a/arch/x86/um/shared/sysdep/ptrace_32.h +++ b/arch/x86/um/shared/sysdep/ptrace_32.h @@ -8,10 +8,6 @@ #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) diff --git a/arch/x86/um/shared/sysdep/ptrace_user.h b/arch/x86/um/shared/sysdep/ptrace_user.h index 44782bbad41e..1d1a824fa652 100644 --- a/arch/x86/um/shared/sysdep/ptrace_user.h +++ b/arch/x86/um/shared/sysdep/ptrace_user.h @@ -15,14 +15,12 @@ #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 diff --git a/arch/x86/um/shared/sysdep/stub_32.h b/arch/x86/um/shared/sysdep/stub_32.h index 38fa894b65d0..ea8b5a2d67af 100644 --- a/arch/x86/um/shared/sysdep/stub_32.h +++ b/arch/x86/um/shared/sysdep/stub_32.h @@ -12,72 +12,79 @@ #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 ;" diff --git a/arch/x86/um/shared/sysdep/stub_64.h b/arch/x86/um/shared/sysdep/stub_64.h index 2de1c8f88173..b24168ef0ac4 100644 --- a/arch/x86/um/shared/sysdep/stub_64.h +++ b/arch/x86/um/shared/sysdep/stub_64.h @@ -16,7 +16,7 @@ #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; @@ -27,7 +27,7 @@ static inline long stub_syscall0(long syscall) 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; @@ -38,7 +38,8 @@ static inline long stub_syscall2(long syscall, long arg1, long arg2) 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; @@ -50,7 +51,7 @@ static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3) 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; @@ -64,8 +65,8 @@ static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3, 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; @@ -78,12 +79,12 @@ static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3, 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 ;" diff --git a/arch/x86/um/syscalls_64.c b/arch/x86/um/syscalls_64.c index 27b29ae6c471..6a00a28c9cca 100644 --- a/arch/x86/um/syscalls_64.c +++ b/arch/x86/um/syscalls_64.c @@ -16,60 +16,24 @@ 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; } @@ -83,10 +47,10 @@ SYSCALL_DEFINE2(arch_prctl, int, option, unsigned long, arg2) 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, diff --git a/arch/x86/um/tls_64.c b/arch/x86/um/tls_64.c index ebd3855d9b13..c51a613f6f5c 100644 --- a/arch/x86/um/tls_64.c +++ b/arch/x86/um/tls_64.c @@ -12,7 +12,7 @@ int arch_set_tls(struct task_struct *t, unsigned long tls) * 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; } |