[PATCH 10/20] ARC: kernel stack: INIT_THREAD need not setup @init_stack in @ksp

Vineet Gupta
2023-08-15T00:48:58Z

There are 2 pointers to kernel mode stack of a task
- task_struct.stack: base address of stack page (max possible stack top)
- thread_info.ksp : runtime stack top in __switch_to

INIT_THREAD was setting up ksp to stack base which was not really needed
- it would get overwritten with dynamic value on first call to
__switch_to when init is switched out for the very first time.
- generic code already does
init_task.stack = init_stack
and ARC code uses that to retrieve task's stack base.

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
---
arch/arc/include/asm/processor.h | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h
index fb844fce1ab6..82ddc929d6e7 100644
--- a/arch/arc/include/asm/processor.h
+++ b/arch/arc/include/asm/processor.h
@@ -33,9 +33,7 @@ struct thread_struct {
#endif
};

-#define INIT_THREAD { \
- .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
-}
+#define INIT_THREAD { }

/* Forward declaration, a strange C thing */
struct task_struct;
--
2.34.1