[PATCH 2/2] kernel image probe function return value checking fix

[Dave Young]

Currently kexec will use the kernel image type when probe function return
value >=0. It looks odd, but previously it works. Since commit bf06cf2095
it does not work anymore.

During my testing for arm zImage, in 2nd kernel the atags pointer and the
machine_id are not valid, I did a lot of debugging in kernel, finally I found
this is caused by a kexec tools bug instead.

Because uImage will be probed before zImage, also the uImage probe return 1
instead of -1 since bf06cf2095, thus kexec will mistakenly think it is uImage.

Fix this issue by regarding it's valid only when probe return 0.

Signed-off-by: Dave Young <dyoung at redhat.com>
---
 kexec/kexec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kexec/kexec.c b/kexec/kexec.c
index f13e512..703d524 100644
--- a/kexec/kexec.c
+++ b/kexec/kexec.c
@@ -691,7 +691,7 @@ static int my_load(const char *type, int fileind, int argc, char **argv,
 	}
 	if (!type || guess_only) {
 		for (i = 0; i < file_types; i++) {
-			if (file_type[i].probe(kernel_buf, kernel_size) >= 0)
+			if (file_type[i].probe(kernel_buf, kernel_size) == 0)
 				break;
 		}
 		if (i == file_types) {
-- 
1.8.3.1