Use the more generic functions get_signal() signal_setup_done()
for signal delivery.

Signed-off-by: Richard Weinberger <richard@nod.at>

...otherwise me lose user mode regs and the resulting
stack trace is useless.

Signed-off-by: Richard Weinberger <richard@nod.at>

If do_ops() fails we have to release current->mm->mmap_sem
otherwise the failing task will never terminate.

Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

Trinity discovered an execution path such that a task
can unmap his stub page.

Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

The reverse case of this race (you must msync before read) is
well known. This is the not so common one.

It can be triggered only on systems which do a lot of task
switching and only at UML startup. If you are starting 200+ UMLs
~ 0.5% will always die without this fix.

Signed-off-by: Anton Ivanov <antivano@cisco.com>
[rw: minor whitespace fixes]
Signed-off-by: Richard Weinberger <richard@nod.at>

arch_align_stack() moved to asm/exec.h, so change the comment referring to
asm/system.h which no longer exists.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We cannot use print_stack_trace because the name conflicts
with linux/stacktrace.h.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

Pull UML changes from Richard Weinberger:
 "This pile contains a nice defconfig cleanup, a rewritten stack
  unwinder and various cleanups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: Remove unused declarations from <as-layout.h>
  um: remove used STDIO_CONSOLE Kconfig param
  um/vdso: add .gitignore for a couple of targets
  arch/um: make it work with defconfig and x86_64
  um: Make kstack_depth_to_print conform to arch/x86
  um: Get rid of thread_struct->saved_task
  um: Make stack trace reliable against kernel mode faults
  um: Rewrite show_stack()

_end is used, but it's already provided by <asm/sections.h>, so use that.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: user-mode-linux-devel@lists.sourceforge.net
Signed-off-by: Richard Weinberger <richard@nod.at>

Signed-off-by: Richard Weinberger <richard@nod.at>