[PATCH] proc/wchan: Use printk format instead of lookup_symbol_name()

From: Helge Deller
Date: Thu Dec 17 2020 - 11:55:54 EST


To resolve the symbol fuction name for wchan, use the printk format
specifier %ps instead of manually looking up the symbol function name
via lookup_symbol_name().

Signed-off-by: Helge Deller <deller@xxxxxx>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index b362523a9829..c4593e1cafa4 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -67,7 +67,6 @@
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/rcupdate.h>
-#include <linux/kallsyms.h>
#include <linux/stacktrace.h>
#include <linux/resource.h>
#include <linux/module.h>
@@ -386,19 +385,17 @@ static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task)
{
unsigned long wchan;
- char symname[KSYM_NAME_LEN];

- if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
- goto print0;
+ if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
+ wchan = get_wchan(task);
+ else
+ wchan = 0;

- wchan = get_wchan(task);
- if (wchan && !lookup_symbol_name(wchan, symname)) {
- seq_puts(m, symname);
- return 0;
- }
+ if (wchan)
+ seq_printf(m, "%ps", (void *) wchan);
+ else
+ seq_putc(m, '0');

-print0:
- seq_putc(m, '0');
return 0;
}
#endif /* CONFIG_KALLSYMS */