diff options
Diffstat (limited to 'arch/x86/um/os-Linux')
| -rw-r--r-- | arch/x86/um/os-Linux/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/um/os-Linux/mcontext.c | 16 | ||||
| -rw-r--r-- | arch/x86/um/os-Linux/registers.c | 152 | ||||
| -rw-r--r-- | arch/x86/um/os-Linux/task_size.c | 151 | ||||
| -rw-r--r-- | arch/x86/um/os-Linux/tls.c | 1 |
5 files changed, 62 insertions, 260 deletions
diff --git a/arch/x86/um/os-Linux/Makefile b/arch/x86/um/os-Linux/Makefile index 5249bbc30dcd..77a308aaa5ec 100644 --- a/arch/x86/um/os-Linux/Makefile +++ b/arch/x86/um/os-Linux/Makefile @@ -3,7 +3,7 @@ # Licensed under the GPL # -obj-y = registers.o task_size.o mcontext.o +obj-y = registers.o mcontext.o obj-$(CONFIG_X86_32) += tls.o diff --git a/arch/x86/um/os-Linux/mcontext.c b/arch/x86/um/os-Linux/mcontext.c index 49c3744cac37..37decaa74761 100644 --- a/arch/x86/um/os-Linux/mcontext.c +++ b/arch/x86/um/os-Linux/mcontext.c @@ -3,6 +3,8 @@ #define __FRAME_OFFSETS #include <asm/ptrace.h> #include <sysdep/ptrace.h> +#include <sysdep/mcontext.h> +#include <arch.h> void get_regs_from_mc(struct uml_pt_regs *regs, mcontext_t *mc) { @@ -26,7 +28,17 @@ void get_regs_from_mc(struct uml_pt_regs *regs, mcontext_t *mc) COPY(RIP); COPY2(EFLAGS, EFL); COPY2(CS, CSGSFS); - regs->gp[CS / sizeof(unsigned long)] &= 0xffff; - regs->gp[CS / sizeof(unsigned long)] |= 3; + regs->gp[SS / sizeof(unsigned long)] = mc->gregs[REG_CSGSFS] >> 48; +#endif +} + +void mc_set_rip(void *_mc, void *target) +{ + mcontext_t *mc = _mc; + +#ifdef __i386__ + mc->gregs[REG_EIP] = (unsigned long)target; +#else + mc->gregs[REG_RIP] = (unsigned long)target; #endif } diff --git a/arch/x86/um/os-Linux/registers.c b/arch/x86/um/os-Linux/registers.c index df8f4b4bf98b..eb1cdadc8a61 100644 --- a/arch/x86/um/os-Linux/registers.c +++ b/arch/x86/um/os-Linux/registers.c @@ -16,132 +16,72 @@ #include <asm/sigcontext.h> #include <linux/elf.h> #include <registers.h> +#include <sys/mman.h> -int have_xstate_support; +static unsigned long ptrace_regset; +unsigned long host_fp_size; -int save_i387_registers(int pid, unsigned long *fp_regs) -{ - if (ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0) - return -errno; - return 0; -} - -int save_fp_registers(int pid, unsigned long *fp_regs) +int get_fp_registers(int pid, unsigned long *regs) { -#ifdef PTRACE_GETREGSET - struct iovec iov; + struct iovec iov = { + .iov_base = regs, + .iov_len = host_fp_size, + }; - if (have_xstate_support) { - iov.iov_base = fp_regs; - iov.iov_len = FP_SIZE * sizeof(unsigned long); - if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0) - return -errno; - return 0; - } else -#endif - return save_i387_registers(pid, fp_regs); -} - -int restore_i387_registers(int pid, unsigned long *fp_regs) -{ - if (ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0) + if (ptrace(PTRACE_GETREGSET, pid, ptrace_regset, &iov) < 0) return -errno; return 0; } -int restore_fp_registers(int pid, unsigned long *fp_regs) -{ -#ifdef PTRACE_SETREGSET - struct iovec iov; - if (have_xstate_support) { - iov.iov_base = fp_regs; - iov.iov_len = FP_SIZE * sizeof(unsigned long); - if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0) - return -errno; - return 0; - } else -#endif - return restore_i387_registers(pid, fp_regs); -} - -#ifdef __i386__ -int have_fpx_regs = 1; -int save_fpx_registers(int pid, unsigned long *fp_regs) +int put_fp_registers(int pid, unsigned long *regs) { - if (ptrace(PTRACE_GETFPXREGS, pid, 0, fp_regs) < 0) - return -errno; - return 0; -} + struct iovec iov = { + .iov_base = regs, + .iov_len = host_fp_size, + }; -int restore_fpx_registers(int pid, unsigned long *fp_regs) -{ - if (ptrace(PTRACE_SETFPXREGS, pid, 0, fp_regs) < 0) + if (ptrace(PTRACE_SETREGSET, pid, ptrace_regset, &iov) < 0) return -errno; return 0; } -int get_fp_registers(int pid, unsigned long *regs) -{ - if (have_fpx_regs) - return save_fpx_registers(pid, regs); - else - return save_fp_registers(pid, regs); -} - -int put_fp_registers(int pid, unsigned long *regs) -{ - if (have_fpx_regs) - return restore_fpx_registers(pid, regs); - else - return restore_fp_registers(pid, regs); -} - -void arch_init_registers(int pid) +int arch_init_registers(int pid) { - struct user_fpxregs_struct fpx_regs; - int err; - - err = ptrace(PTRACE_GETFPXREGS, pid, 0, &fpx_regs); - if (!err) - return; - - if (errno != EIO) - panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d", - errno); - - have_fpx_regs = 0; -} + struct iovec iov = { + /* Just use plenty of space, it does not cost us anything */ + .iov_len = 2 * 1024 * 1024, + }; + int ret; + + iov.iov_base = mmap(NULL, iov.iov_len, PROT_WRITE | PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + if (iov.iov_base == MAP_FAILED) + return -ENOMEM; + + /* GDB has x86_xsave_length, which uses x86_cpuid_count */ + ptrace_regset = NT_X86_XSTATE; + ret = ptrace(PTRACE_GETREGSET, pid, ptrace_regset, &iov); + if (ret) + ret = -errno; + + if (ret == -ENODEV) { +#ifdef CONFIG_X86_32 + ptrace_regset = NT_PRXFPREG; #else + ptrace_regset = NT_PRFPREG; +#endif + iov.iov_len = 2 * 1024 * 1024; + ret = ptrace(PTRACE_GETREGSET, pid, ptrace_regset, &iov); + if (ret) + ret = -errno; + } -int get_fp_registers(int pid, unsigned long *regs) -{ - return save_fp_registers(pid, regs); -} - -int put_fp_registers(int pid, unsigned long *regs) -{ - return restore_fp_registers(pid, regs); -} - -void arch_init_registers(int pid) -{ -#ifdef PTRACE_GETREGSET - void * fp_regs; - struct iovec iov; - - fp_regs = malloc(FP_SIZE * sizeof(unsigned long)); - if(fp_regs == NULL) - return; + munmap(iov.iov_base, 2 * 1024 * 1024); - iov.iov_base = fp_regs; - iov.iov_len = FP_SIZE * sizeof(unsigned long); - if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0) - have_xstate_support = 1; + host_fp_size = iov.iov_len; - free(fp_regs); -#endif + return ret; } -#endif unsigned long get_thread_reg(int reg, jmp_buf *buf) { diff --git a/arch/x86/um/os-Linux/task_size.c b/arch/x86/um/os-Linux/task_size.c deleted file mode 100644 index 1dc9adc20b1c..000000000000 --- a/arch/x86/um/os-Linux/task_size.c +++ /dev/null @@ -1,151 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#include <stdio.h> -#include <stdlib.h> -#include <signal.h> -#include <sys/mman.h> -#include <longjmp.h> - -#ifdef __i386__ - -static jmp_buf buf; - -static void segfault(int sig) -{ - longjmp(buf, 1); -} - -static int page_ok(unsigned long page) -{ - unsigned long *address = (unsigned long *) (page << UM_KERN_PAGE_SHIFT); - unsigned long n = ~0UL; - void *mapped = NULL; - int ok = 0; - - /* - * First see if the page is readable. If it is, it may still - * be a VDSO, so we go on to see if it's writable. If not - * then try mapping memory there. If that fails, then we're - * still in the kernel area. As a sanity check, we'll fail if - * the mmap succeeds, but gives us an address different from - * what we wanted. - */ - if (setjmp(buf) == 0) - n = *address; - else { - mapped = mmap(address, UM_KERN_PAGE_SIZE, - PROT_READ | PROT_WRITE, - MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - if (mapped == MAP_FAILED) - return 0; - if (mapped != address) - goto out; - } - - /* - * Now, is it writeable? If so, then we're in user address - * space. If not, then try mprotecting it and try the write - * again. - */ - if (setjmp(buf) == 0) { - *address = n; - ok = 1; - goto out; - } else if (mprotect(address, UM_KERN_PAGE_SIZE, - PROT_READ | PROT_WRITE) != 0) - goto out; - - if (setjmp(buf) == 0) { - *address = n; - ok = 1; - } - - out: - if (mapped != NULL) - munmap(mapped, UM_KERN_PAGE_SIZE); - return ok; -} - -unsigned long os_get_top_address(void) -{ - struct sigaction sa, old; - unsigned long bottom = 0; - /* - * A 32-bit UML on a 64-bit host gets confused about the VDSO at - * 0xffffe000. It is mapped, is readable, can be reprotected writeable - * and written. However, exec discovers later that it can't be - * unmapped. So, just set the highest address to be checked to just - * below it. This might waste some address space on 4G/4G 32-bit - * hosts, but shouldn't hurt otherwise. - */ - unsigned long top = 0xffffd000 >> UM_KERN_PAGE_SHIFT; - unsigned long test, original; - - printf("Locating the bottom of the address space ... "); - fflush(stdout); - - /* - * We're going to be longjmping out of the signal handler, so - * SA_DEFER needs to be set. - */ - sa.sa_handler = segfault; - sigemptyset(&sa.sa_mask); - sa.sa_flags = SA_NODEFER; - if (sigaction(SIGSEGV, &sa, &old)) { - perror("os_get_top_address"); - exit(1); - } - - /* Manually scan the address space, bottom-up, until we find - * the first valid page (or run out of them). - */ - for (bottom = 0; bottom < top; bottom++) { - if (page_ok(bottom)) - break; - } - - /* If we've got this far, we ran out of pages. */ - if (bottom == top) { - fprintf(stderr, "Unable to determine bottom of address " - "space.\n"); - exit(1); - } - - printf("0x%lx\n", bottom << UM_KERN_PAGE_SHIFT); - printf("Locating the top of the address space ... "); - fflush(stdout); - - original = bottom; - - /* This could happen with a 4G/4G split */ - if (page_ok(top)) - goto out; - - do { - test = bottom + (top - bottom) / 2; - if (page_ok(test)) - bottom = test; - else - top = test; - } while (top - bottom > 1); - -out: - /* Restore the old SIGSEGV handling */ - if (sigaction(SIGSEGV, &old, NULL)) { - perror("os_get_top_address"); - exit(1); - } - top <<= UM_KERN_PAGE_SHIFT; - printf("0x%lx\n", top); - - return top; -} - -#else - -unsigned long os_get_top_address(void) -{ - /* The old value of CONFIG_TOP_ADDR */ - return 0x7fc0002000; -} - -#endif diff --git a/arch/x86/um/os-Linux/tls.c b/arch/x86/um/os-Linux/tls.c index 3e1b1bf6acbc..eed9efe29ade 100644 --- a/arch/x86/um/os-Linux/tls.c +++ b/arch/x86/um/os-Linux/tls.c @@ -6,6 +6,7 @@ #include <sys/syscall.h> #include <unistd.h> +#include <os.h> #include <sysdep/tls.h> #ifndef PTRACE_GET_THREAD_AREA |