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From:   Rick Edgecombe <rick.p.edgecombe@intel.com>
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Cc:     rick.p.edgecombe@intel.com, Yu-cheng Yu <yu-cheng.yu@intel.com>
Subject: [PATCH 26/35] x86/process: Change copy_thread() argument 'arg' to 'stack_size'
Date:   Sun, 30 Jan 2022 13:18:29 -0800
Message-Id: <20220130211838.8382-27-rick.p.edgecombe@intel.com>
In-Reply-To: <20220130211838.8382-1-rick.p.edgecombe@intel.com>
References: <20220130211838.8382-1-rick.p.edgecombe@intel.com>
Precedence: bulk

From: Yu-cheng Yu <yu-cheng.yu@intel.com>

The single call site of copy_thread() passes stack size in 'arg'.  To make
this clear and in preparation of using this argument for shadow stack
allocation, change 'arg' to 'stack_size'.  No functional changes.

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
---
 arch/x86/kernel/process.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 81d8ef036637..82a816178e7f 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -130,8 +130,9 @@ static int set_new_tls(struct task_struct *p, unsigned long tls)
 		return do_set_thread_area_64(p, ARCH_SET_FS, tls);
 }
 
-int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
-		struct task_struct *p, unsigned long tls)
+int copy_thread(unsigned long clone_flags, unsigned long sp,
+		unsigned long stack_size, struct task_struct *p,
+		unsigned long tls)
 {
 	struct inactive_task_frame *frame;
 	struct fork_frame *fork_frame;
@@ -175,7 +176,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 	if (unlikely(p->flags & PF_KTHREAD)) {
 		p->thread.pkru = pkru_get_init_value();
 		memset(childregs, 0, sizeof(struct pt_regs));
-		kthread_frame_init(frame, sp, arg);
+		kthread_frame_init(frame, sp, stack_size);
 		return 0;
 	}
 
@@ -208,7 +209,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 		 */
 		childregs->sp = 0;
 		childregs->ip = 0;
-		kthread_frame_init(frame, sp, arg);
+		kthread_frame_init(frame, sp, stack_size);
 		return 0;
 	}
 
-- 
2.17.1