[PATCH v5 25/32] um: Stop conflating task_struct::stack with thread_info

From: Andy Lutomirski
Date: Mon Jul 11 2016 - 16:57:26 EST


From: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>

thread_info may move in the future, so use the accessors.

Andy Lutomirski wrote this changelog message and changed
"task_thread_info(child)->cpu" to "task_cpu(child)".

Message-Id: <CA+55aFxvZhBu9U1cqpVm4frv0p5mqu=0TxsSqE-=95ft8HvCVA@xxxxxxxxxxxxxx>
Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
arch/x86/um/ptrace_32.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/um/ptrace_32.c b/arch/x86/um/ptrace_32.c
index ebd4dd6ef73b..2a6f781ce9cf 100644
--- a/arch/x86/um/ptrace_32.c
+++ b/arch/x86/um/ptrace_32.c
@@ -191,7 +191,7 @@ int peek_user(struct task_struct *child, long addr, long data)

static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
- int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
+ int err, n, cpu = task_cpu(child);
struct user_i387_struct fpregs;

err = save_i387_registers(userspace_pid[cpu],
@@ -208,7 +208,7 @@ static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *c

static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
- int n, cpu = ((struct thread_info *) child->stack)->cpu;
+ int n, cpu = task_cpu(child);
struct user_i387_struct fpregs;

n = copy_from_user(&fpregs, buf, sizeof(fpregs));
@@ -221,7 +221,7 @@ static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *c

static int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
{
- int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
+ int err, n, cpu = task_cpu(child);
struct user_fxsr_struct fpregs;

err = save_fpx_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
@@ -237,7 +237,7 @@ static int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *

static int set_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
{
- int n, cpu = ((struct thread_info *) child->stack)->cpu;
+ int n, cpu = task_cpu(child);
struct user_fxsr_struct fpregs;

n = copy_from_user(&fpregs, buf, sizeof(fpregs));
--
2.7.4