uml: stop specially protecting kernel stacks

Map all of physical memory as executable to avoid having to change stack
protections during fork and exit.

unprotect_stack is now called only from MODE_TT code, so it is marked as such.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jeff Dike 2007-10-16 01:26:46 -07:00 committed by Linus Torvalds
parent 8d82076080
commit 5c8aaceab8
4 changed files with 7 additions and 4 deletions

View file

@ -82,7 +82,9 @@ extern void check_stack_overflow(void *ptr);
extern void relay_signal(int sig, union uml_pt_regs *regs);
extern int user_context(unsigned long sp);
extern void timer_irq(union uml_pt_regs *regs);
#ifdef CONFIG_MODE_TT
extern void unprotect_stack(unsigned long stack);
#endif
extern void do_uml_exitcalls(void);
extern int attach_debugger(int idle_pid, int pid, int stop);
extern int config_gdb(char *str);

View file

@ -47,7 +47,9 @@ union thread_union cpu0_irqstack
__attribute__((__section__(".data.init_irqstack"))) =
{ INIT_THREAD_INFO(init_task) };
#ifdef CONFIG_MODE_TT
void unprotect_stack(unsigned long stack)
{
os_protect_memory((void *) stack, THREAD_SIZE, 1, 1, 0);
}
#endif

View file

@ -105,7 +105,7 @@ void __init setup_physmem(unsigned long start, unsigned long reserve_end,
offset = uml_reserved - uml_physmem;
err = os_map_memory((void *) uml_reserved, physmem_fd, offset,
len - offset, 1, 1, 0);
len - offset, 1, 1, 1);
if(err < 0){
os_print_error(err, "Mapping memory");
exit(1);

View file

@ -82,9 +82,9 @@ unsigned long alloc_stack(int order, int atomic)
if (atomic)
flags = GFP_ATOMIC;
page = __get_free_pages(flags, order);
if(page == 0)
if (page == 0)
return 0;
stack_protections(page);
return page;
}
@ -141,7 +141,6 @@ void release_thread(struct task_struct *task)
void exit_thread(void)
{
unprotect_stack((unsigned long) current_thread);
}
void *get_current(void)