[Crash-utility] [PATCH] arm64: fix a backtracing for CONFIG_THREAD_INFO_IN_TASK kernel

[AKASHI Takahiro]

Since v4.10, arm64 kernel supports CONFIG_THREAD_INFO_IN_TASK.
This means that bt->tc->thread_info is no longer equal to the base
address of the task's stack.
This patch fixes this issue.

Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
---
 arm64.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arm64.c b/arm64.c
index e4d497e..2b17081 100644
--- a/arm64.c
+++ b/arm64.c
@@ -2447,7 +2447,7 @@ arm64_in_kdump_text(struct bt_info *bt, struct arm64_stackframe *frame)
 			    (*ptr < ms->crash_kexec_end) &&
 			    INSTACK(*(ptr - 1), bt)) {
 				bt->bptr = ((ulong)(ptr - 1) - (ulong)base)
-					   + bt->tc->thread_info;
+					   + task_to_stackbase(bt->tc->task);
 				if (CRASHDEBUG(1))
 					fprintf(fp, "%lx: %lx (crash_kexec)\n", bt->bptr, *ptr);
 				return TRUE;
@@ -2456,20 +2456,22 @@ arm64_in_kdump_text(struct bt_info *bt, struct arm64_stackframe *frame)
 			    (*ptr < ms->crash_save_cpu_end) &&
 			    INSTACK(*(ptr - 1), bt)) {
 				bt->bptr = ((ulong)(ptr - 1) - (ulong)base)
-					   + bt->tc->thread_info;
+					   + task_to_stackbase(bt->tc->task);
 				if (CRASHDEBUG(1))
 					fprintf(fp, "%lx: %lx (crash_save_cpu)\n", bt->bptr, *ptr);
 				return TRUE;
 			}
 		} else {
 			if ((*ptr >= ms->crash_kexec_start) && (*ptr < ms->crash_kexec_end)) {
-				bt->bptr = ((ulong)ptr - (ulong)base) + bt->tc->thread_info;
+				bt->bptr = ((ulong)ptr - (ulong)base)
+					   + task_to_stackbase(bt->tc->task);
 				if (CRASHDEBUG(1))
 					fprintf(fp, "%lx: %lx (crash_kexec)\n", bt->bptr, *ptr);
 				return TRUE;
 			}
 			if ((*ptr >= ms->crash_save_cpu_start) && (*ptr < ms->crash_save_cpu_end)) {
-				bt->bptr = ((ulong)ptr - (ulong)base) + bt->tc->thread_info;
+				bt->bptr = ((ulong)ptr - (ulong)base)
+					   + task_to_stackbase(bt->tc->task);
 				if (CRASHDEBUG(1))
 					fprintf(fp, "%lx: %lx (crash_save_cpu)\n", bt->bptr, *ptr);
 				return TRUE;
-- 
2.11.0