From: Vasily Gorbik <gor@linux.ibm.com>
Date: Fri, 22 Nov 2019 12:35:34 +0100
Subject: s390/unwind: unify task is current checks
Git-commit: 103b4cca60d2c8c51f1290cc984b7046ccb8b46d
Patch-mainline: v5.5-rc1
References: jsc#SLE-11050
Avoid mixture of task == NULL and task == current meaning the same
thing and simply always initialize task with current in unwind_start.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
---
arch/s390/include/asm/stacktrace.h | 2 +-
arch/s390/include/asm/unwind.h | 3 ++-
arch/s390/kernel/dumpstack.c | 4 ----
3 files changed, 3 insertions(+), 6 deletions(-)
diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h
index fee40212af11..0ae4bbf7779c 100644
--- a/arch/s390/include/asm/stacktrace.h
+++ b/arch/s390/include/asm/stacktrace.h
@@ -38,7 +38,7 @@ static inline unsigned long get_stack_pointer(struct task_struct *task,
{
if (regs)
return (unsigned long) kernel_stack_pointer(regs);
- if (!task || task == current)
+ if (task == current)
return current_stack_pointer();
return (unsigned long) task->thread.ksp;
}
diff --git a/arch/s390/include/asm/unwind.h b/arch/s390/include/asm/unwind.h
index eaaefeceef6f..a2d8dd766987 100644
--- a/arch/s390/include/asm/unwind.h
+++ b/arch/s390/include/asm/unwind.h
@@ -61,7 +61,8 @@ static inline void unwind_start(struct unwind_state *state,
struct pt_regs *regs,
unsigned long sp)
{
- sp = sp ? : get_stack_pointer(task, regs);
+ task = task ?: current;
+ sp = sp ?: get_stack_pointer(task, regs);
__unwind_start(state, task, regs, sp);
}
diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
index 34bdc60c0b11..fc442aec0d96 100644
--- a/arch/s390/kernel/dumpstack.c
+++ b/arch/s390/kernel/dumpstack.c
@@ -93,8 +93,6 @@ int get_stack_info(unsigned long sp, struct task_struct *task,
if (!sp)
goto unknown;
- task = task ? : current;
-
/* Check per-task stack */
if (in_task_stack(sp, task, info))
goto recursion_check;
@@ -128,8 +126,6 @@ void show_stack(struct task_struct *task, unsigned long *stack)
struct unwind_state state;
printk("Call Trace:\n");
- if (!task)
- task = current;
unwind_for_each_frame(&state, task, NULL, (unsigned long) stack)
printk(state.reliable ? " [<%016lx>] %pSR \n" :
"([<%016lx>] %pSR)\n",