[PATCH 1/2] riscv: Add dump stack in show_regs

[Kefeng Wang]

hi Palmer, kindly ping...

On 2020/11/24 19:20, Kefeng Wang wrote:
> Like commit 1149aad10b1e ("arm64: Add dump_backtrace() in show_regs"),
> dump the stack in riscv show_regs as common code expects.
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang at huawei.com>
> ---
> NOTE: The patches based on
> https://patchwork.kernel.org/project/linux-riscv/list/?series=383349
>
>   arch/riscv/include/asm/bug.h        |  1 +
>   arch/riscv/include/asm/stacktrace.h |  2 ++
>   arch/riscv/kernel/process.c         |  9 ++++++++-
>   arch/riscv/kernel/stacktrace.c      | 10 ++++++++--
>   arch/riscv/kernel/traps.c           |  3 ++-
>   5 files changed, 21 insertions(+), 4 deletions(-)
>
> diff --git a/arch/riscv/include/asm/bug.h b/arch/riscv/include/asm/bug.h
> index d6f1ec08d97b..d3804a2f9aad 100644
> --- a/arch/riscv/include/asm/bug.h
> +++ b/arch/riscv/include/asm/bug.h
> @@ -85,6 +85,7 @@ do {								\
>   struct pt_regs;
>   struct task_struct;
>   
> +void __show_regs(struct pt_regs *regs);
>   void die(struct pt_regs *regs, const char *str);
>   void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr);
>   
> diff --git a/arch/riscv/include/asm/stacktrace.h b/arch/riscv/include/asm/stacktrace.h
> index 470a65c4ccdc..3450c1912afd 100644
> --- a/arch/riscv/include/asm/stacktrace.h
> +++ b/arch/riscv/include/asm/stacktrace.h
> @@ -13,5 +13,7 @@ struct stackframe {
>   
>   extern void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs,
>   				    bool (*fn)(void *, unsigned long), void *arg);
> +extern void dump_backtrace(struct pt_regs *regs, struct task_struct *task,
> +			   const char *loglvl);
>   
>   #endif /* _ASM_RISCV_STACKTRACE_H */
> diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> index 19225ec65db6..e41b733abeaa 100644
> --- a/arch/riscv/kernel/process.c
> +++ b/arch/riscv/kernel/process.c
> @@ -18,6 +18,7 @@
>   #include <asm/unistd.h>
>   #include <asm/processor.h>
>   #include <asm/csr.h>
> +#include <asm/stacktrace.h>
>   #include <asm/string.h>
>   #include <asm/switch_to.h>
>   #include <asm/thread_info.h>
> @@ -39,7 +40,7 @@ void arch_cpu_idle(void)
>   	local_irq_enable();
>   }
>   
> -void show_regs(struct pt_regs *regs)
> +void __show_regs(struct pt_regs *regs)
>   {
>   	show_regs_print_info(KERN_DEFAULT);
>   
> @@ -69,6 +70,12 @@ void show_regs(struct pt_regs *regs)
>   	pr_cont("status: " REG_FMT " badaddr: " REG_FMT " cause: " REG_FMT "\n",
>   		regs->status, regs->badaddr, regs->cause);
>   }
> +void show_regs(struct pt_regs *regs)
> +{
> +	__show_regs(regs);
> +	if (!user_mode(regs))
> +		dump_backtrace(regs, NULL, KERN_DEFAULT);
> +}
>   
>   void start_thread(struct pt_regs *regs, unsigned long pc,
>   	unsigned long sp)
> diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
> index 48b870a685b3..76dadf6d396b 100644
> --- a/arch/riscv/kernel/stacktrace.c
> +++ b/arch/riscv/kernel/stacktrace.c
> @@ -101,10 +101,16 @@ static bool print_trace_address(void *arg, unsigned long pc)
>   	return true;
>   }
>   
> +void dump_backtrace(struct pt_regs *regs, struct task_struct *task,
> +		    const char *loglvl)
> +{
> +	pr_cont("%sCall Trace:\n", loglvl);
> +	walk_stackframe(task, regs, print_trace_address, (void *)loglvl);
> +}
> +
>   void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)
>   {
> -	pr_cont("Call Trace:\n");
> -	walk_stackframe(task, NULL, print_trace_address, (void *)loglvl);
> +	dump_backtrace(NULL, task, loglvl);
>   }
>   
>   static bool save_wchan(void *arg, unsigned long pc)
> diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
> index ad14f4466d92..570eb078b1e1 100644
> --- a/arch/riscv/kernel/traps.c
> +++ b/arch/riscv/kernel/traps.c
> @@ -16,6 +16,7 @@
>   #include <linux/module.h>
>   #include <linux/irq.h>
>   
> +#include <asm/bug.h>
>   #include <asm/processor.h>
>   #include <asm/ptrace.h>
>   #include <asm/csr.h>
> @@ -66,7 +67,7 @@ void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr)
>   			tsk->comm, task_pid_nr(tsk), signo, code, addr);
>   		print_vma_addr(KERN_CONT " in ", instruction_pointer(regs));
>   		pr_cont("\n");
> -		show_regs(regs);
> +		__show_regs(regs);
>   	}
>   
>   	force_sig_fault(signo, code, (void __user *)addr);