[PATCH 1/2] kexec: accumulate kexec_crash_size if crashk_low_res defined

[Kaihao Bai <carlo.bai@linux.alibaba.com>]

Currently x86 and arm64 support to reserve low memory range for
crashkernel. When crashkernel=Y,low is defined, the main kernel would
reserve another memblock (instead of crashkernel=X,high, which stored
in crashk_res) for crashkernel and store it in crashk_low_res. But
the value of /sys/kernel/kexec_crash_size only calculates the size of
crashk_res size is not calculated.

To ensure the consistency of /sys/kernel/kexec_crash_size, when
crashk_low_res is defined, its size needs to be accumulated to
kexec_crash_size.

Signed-off-by: Kaihao Bai <carlo.bai@linux.alibaba.com>
---
 kernel/kexec_core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 4d34c78..137f6eb 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -1016,6 +1016,8 @@ size_t crash_get_memory_size(void)
 	mutex_lock(&kexec_mutex);
 	if (crashk_res.end != crashk_res.start)
 		size = resource_size(&crashk_res);
+	if (crashk_low_res.end != crashk_low_res.start)
+		size += resource_size(&crashk_low_res);
 	mutex_unlock(&kexec_mutex);
 	return size;
 }
-- 
1.8.3.1