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Diffstat (limited to 'arch/um/os-Linux/skas/process.c')
-rw-r--r--arch/um/os-Linux/skas/process.c117
1 files changed, 36 insertions, 81 deletions
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 9464833e74..1f5c3f2523 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;
}