From mboxrd@z Thu Jan 1 00:00:00 1970 From: mark.rutland@arm.com (Mark Rutland) Date: Wed, 19 Oct 2016 20:10:28 +0100 Subject: [PATCH 04/10] arm64: traps: simplify die() and __die() In-Reply-To: <1476904234-9511-1-git-send-email-mark.rutland@arm.com> References: <1476904234-9511-1-git-send-email-mark.rutland@arm.com> Message-ID: <1476904234-9511-5-git-send-email-mark.rutland@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 Cc: Catalin Marinas Cc: Will Deacon --- arch/arm64/kernel/traps.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 32d4bdb..1cfbe10 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -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 int __die(const char *str, int err, struct thread_info *thread, */ 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); -- 1.9.1