powerpc/kexec_file: print configured kernel command line

[Sourabh Jain]

Kexec with the -d option prints extra logs about the kexec/kdump kernel
that help debug kexec and kdump. For example, it shows what kexec
segments are loaded, their locations, and sizes.

One key piece of information still missing is the kernel command line
configured for the kexec/kdump kernel.

With this patch included, the kernel will print the kernel command line
configured for the kexec/kdump kernel as shown below:

kexec --initrd=./initrd ./kernel -lspd --command-line="test1 test2"

Loaded elf core header at 0x22e30000, bufsz=0x2000 memsz=0x80000
kexec_elf: Command line: elfcorehdr=0x22e30000 test1 test2   <--- New
kexec_elf: Loaded initrd at 0x22eb0000

Cc: Madhavan Srinivasan <maddy at linux.ibm.com>
Cc: Michael Ellerman <mpe at ellerman.id.au>
Signed-off-by: Sourabh Jain <sourabhjain at linux.ibm.com>
---
 arch/powerpc/kexec/elf_64.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index 5d6d616404cf..db0af790c784 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -90,6 +90,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
 		cmdline = modified_cmdline;
 	}
 
+	kexec_dprintk("Command line: %s", cmdline ? cmdline : "");
+
 	if (initrd != NULL) {
 		kbuf.buffer = initrd;
 		kbuf.bufsz = kbuf.memsz = initrd_len;
-- 
2.50.1