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Commit e78acf67ba7e32071e6eca14d8c39c7b1f130c31

Authored by Tiejun Chen
Committed by Jason Wessel
1 parent f7c82d5a3c
Exists in smarc-l5.0.0_1.0.0-ga and in 5 other branches imx_3.10.17_1.0.1_ga, imx_3.10.53_1.1.0_ga, imx_3.14.28_1.0.0_ga, smarc-imx_3.10.53_1.1.0_ga, smarc-imx_3.14.28_1.0.0_ga

kgdb/kgdbts: support ppc64 

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.chen@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

Showing 1 changed file with 2 additions and 0 deletions Side-by-side Diff

drivers/misc/kgdbts.c
Diff comments   View file @ e78acf6
... ... @@ -103,6 +103,7 @@
103 103 #include <linux/delay.h>
104 104 #include <linux/kthread.h>
105 105 #include <linux/module.h>
  106 +#include <asm/sections.h>
106 107  
107 108 #define v1printk(a...) do { \
108 109 if (verbose) \
... ... @@ -222,6 +223,7 @@
222 223 addr = (unsigned long)do_fork;
223 224 else if (!strcmp(arg, "hw_break_val"))
224 225 addr = (unsigned long)&hw_break_val;
  226 + addr = (unsigned long) dereference_function_descriptor((void *)addr);
225 227 return addr;
226 228 }
227 229