commit 1926150ee350e17fee2aeabb8ef781222d94366e

Author: Dave Anderson <anderson@redhat.com>

Date:   Mon Jun 11 13:46:41 2018 -0400

    Fix for the ppc64/ppc64le "bt" command on Linux 4.7 and later kernels

    that contain commit d8bff643d81a58181356c0aa3ab771ac10da6894,

    titled "[x86] asm: Make sure verify_cpu() has a good stack", which

    inadvertently breaks the ppc64/ppc64le kernel stack size calculation

    when running with crash-7.2.2 or later.  Without the patch, "bt" may

    fail with a filtered kdump dumpfile with the two error messages

    "bt: page excluded: kernel virtual address: <address> type: stack

    contents" and "bt: read of stack at <address> failed".

    (anderson@redhat.com)

diff --git a/task.c b/task.c

index f6956d5..1b32629 100644

--- a/task.c

+++ b/task.c

@@ -440,7 +440,7 @@ task_init(void)

 	} else if (VALID_SIZE(thread_union) && 

 	    	((len = SIZE(thread_union)) != STACKSIZE())) {

 		machdep->stacksize = len;

-	} else {

+	} else if (!VALID_SIZE(thread_union) && !VALID_SIZE(task_union)) {

 		if (kernel_symbol_exists("__start_init_task") &&

 		    kernel_symbol_exists("__end_init_task")) {

 			len = symbol_value("__end_init_task");