Commit 7f1a00b6 authored Jun 24, 2016 by Linus Torvalds

fix up initial thread stack pointer vs thread_info confusion



The INIT_TASK() initializer was similarly confused about the stack vs
thread_info allocation that the allocators had, and that were fixed in
commit b235beea ("Clarify naming of thread info/stack allocators").

The task ->stack pointer only incidentally ends up having the same value
as the thread_info, and in fact that will change.

So fix the initial task struct initializer to point to 'init_stack'
instead of 'init_thread_info', and make sure the ia64 definition for
that exists.

This actually makes the ia64 tsk->stack pointer be sensible for the
initial task, but not for any other task.  As mentioned in commit
b235beea, that whole pointer isn't actually used on ia64, since
task_stack_page() there just points to the (single) allocation.

All the other architectures seem to have copied the 'init_stack'
definition, even if it tended to be generally unusued.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent aca9c293

arch/ia64/kernel/init_task.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@ static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
		* handled. This is done by having a special ".data..init_task" section...
		*/
		#define init_thread_info init_task_mem.s.thread_info
		#define init_stack init_task_mem.stack

		union {
		struct {

include/linux/init_task.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -190,7 +190,7 @@ extern struct task_group root_task_group;
		#define INIT_TASK(tsk) \
		{ \
		.state = 0, \
		.stack = &init_thread_info, \
		.stack = init_stack, \
		.usage = ATOMIC_INIT(2), \
		.flags = PF_KTHREAD, \
		.prio = MAX_PRIO-20, \