vsprintf: fix %ps on non symbols when using kallsyms
Using %ps in a printk format will sometimes fail silently and print the
empty string if the address passed in does not match a symbol that
kallsyms knows about. But using %pS will fall back to printing the full
address if kallsyms can't find the symbol. Make %ps act the same as %pS
by falling back to printing the address.
While we're here also make %ps print the module that a symbol comes from
so that it matches what %pS already does. Take this simple function for
example (in a module):
static void test_printk(void)
{
int test;
pr_info("with pS: %pS\n", &test);
pr_info("with ps: %ps\n", &test);
}
Before this patch:
with pS: 0xdff7df44
with ps:
After this patch:
with pS: 0xdff7df44
with ps: 0xdff7df44
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
index 3875719..6883e19 100644
--- a/include/linux/kallsyms.h
+++ b/include/linux/kallsyms.h
@@ -36,6 +36,7 @@
/* Look up a kernel symbol and return it in a text buffer. */
extern int sprint_symbol(char *buffer, unsigned long address);
+extern int sprint_symbol_no_offset(char *buffer, unsigned long address);
extern int sprint_backtrace(char *buffer, unsigned long address);
/* Look up a kernel symbol and print it to the kernel messages. */
@@ -80,6 +81,12 @@
return 0;
}
+static inline int sprint_symbol_no_offset(char *buffer, unsigned long addr)
+{
+ *buffer = '\0';
+ return 0;
+}
+
static inline int sprint_backtrace(char *buffer, unsigned long addr)
{
*buffer = '\0';