arm64: traps: simplify die() and __die()

In arm64's die and __die routines we pass around a thread_info, and
subsequently use this to determine the relevant task_struct, and the end
of the thread's stack. Subsequent patches will decouple thread_info from
the stack, and this approach will no longer work.

To figure out the end of the stack, we can use the new generic
end_of_stack() helper. As we only call __die() from die(), and die()
always deals with the current task, we can remove the parameter and have
both acquire current directly, which also makes it clear that __die
can't be called for arbitrary tasks.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Mark Rutland 2016-11-03 20:23:06 +00:00 committed by Catalin Marinas
parent a9ea0017eb
commit 876e7a38e8

View File

@ -228,10 +228,9 @@ void show_stack(struct task_struct *tsk, unsigned long *sp)
#endif
#define S_SMP " SMP"
static int __die(const char *str, int err, struct thread_info *thread,
struct pt_regs *regs)
static int __die(const char *str, int err, struct pt_regs *regs)
{
struct task_struct *tsk = thread->task;
struct task_struct *tsk = current;
static int die_counter;
int ret;
@ -246,7 +245,8 @@ static int __die(const char *str, int err, struct thread_info *thread,
print_modules();
__show_regs(regs);
pr_emerg("Process %.*s (pid: %d, stack limit = 0x%p)\n",
TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);
TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk),
end_of_stack(tsk));
if (!user_mode(regs)) {
dump_mem(KERN_EMERG, "Stack: ", regs->sp,
@ -265,7 +265,6 @@ static DEFINE_RAW_SPINLOCK(die_lock);
*/
void die(const char *str, struct pt_regs *regs, int err)
{
struct thread_info *thread = current_thread_info();
int ret;
oops_enter();
@ -273,9 +272,9 @@ void die(const char *str, struct pt_regs *regs, int err)
raw_spin_lock_irq(&die_lock);
console_verbose();
bust_spinlocks(1);
ret = __die(str, err, thread, regs);
ret = __die(str, err, regs);
if (regs && kexec_should_crash(thread->task))
if (regs && kexec_should_crash(current))
crash_kexec(regs);
bust_spinlocks(0);