We can't look up the address of the entry point of the function simply
via that function symbol for all architectures.
For PPC64 ABI, actually there is a function descriptors structure.
A function descriptor is a three doubleword data structure that contains
the following values:
* The first doubleword contains the address of the entry point of
the function.
* The second doubleword contains the TOC base address for
the function.
* The third doubleword contains the environment pointer for
languages such as Pascal and PL/1.
So we should call a wapperred dereference_function_descriptor() to get
the address of the entry point of the function.
Note this is also safe for other architecture after refer to
"include/asm-generic/sections.h" since:
dereference_function_descriptor(p) always is (p) if without arched definition.
Signed-off-by: Tiejun Chen <tiejun.c...@windriver.com>
---
drivers/misc/kgdbts.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c
index 3aa9a96..4799e1f 100644
--- a/drivers/misc/kgdbts.c
+++ b/drivers/misc/kgdbts.c
@@ -103,6 +103,7 @@
#include <linux/delay.h>
#include <linux/kthread.h>
#include <linux/module.h>
+#include <asm/sections.h>
#define v1printk(a...) do { \
if (verbose) \
@@ -222,6 +223,7 @@ static unsigned long lookup_addr(char *arg)
addr = (unsigned long)do_fork;
else if (!strcmp(arg, "hw_break_val"))
addr = (unsigned long)&hw_break_val;
+ addr = (unsigned long )dereference_function_descriptor((void *)addr);
return addr;
}
--
1.7.9.5
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