commit 2e1ec106dc5aac951ba884ebe4cca036e9a2d45f

 Author: Sven Schnelle <svens@linux.ibm.com>

 Date:   Thu Dec 16 12:43:56 2021 +0100

     s390: add support for --reuse-cmdline

     --reuse-cmdline reads the command line of the currently

     running kernel from /proc/cmdline and uses that for the

     kernel that should be kexec'd.

     Signed-off-by: Sven Schnelle <svens@linux.ibm.com>

     Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com>

     Signed-off-by: Simon Horman <horms@verge.net.au>

 diff --git a/kexec/arch/s390/include/arch/options.h b/kexec/arch/s390/include/arch/options.h

 index 76044a301ceb3cca013f70dff330a8ad343d808a..c150244996c79165cf1e83e331f728432b752652 100644

 --- a/kexec/arch/s390/include/arch/options.h

 +++ b/kexec/arch/s390/include/arch/options.h

 @@ -1,9 +1,10 @@

  #ifndef KEXEC_ARCH_S390_OPTIONS_H

  #define KEXEC_ARCH_S390_OPTIONS_H

 -#define OPT_ARCH_MAX	(OPT_MAX+0)

 -#define OPT_APPEND	OPT_MAX+0

 -#define OPT_RAMDISK	OPT_MAX+1

 +#define OPT_ARCH_MAX		(OPT_MAX+0)

 +#define OPT_APPEND		(OPT_MAX+0)

 +#define OPT_RAMDISK		(OPT_MAX+1)

 +#define OPT_REUSE_CMDLINE	(OPT_MAX+2)

  /* Options relevant to the architecture (excluding loader-specific ones),

   * in this case none:

 @@ -31,7 +32,8 @@

  	KEXEC_ARCH_OPTIONS				\

  	{"command-line",     1, 0, OPT_APPEND},		\

  	{"append",           1, 0, OPT_APPEND},		\

 -	{"initrd",	     1, 0, OPT_RAMDISK},

 +	{"initrd",	     1, 0, OPT_RAMDISK},	\

 +	{"reuse-cmdline",    0, 0, OPT_REUSE_CMDLINE },

  #define KEXEC_ALL_OPT_STR KEXEC_ARCH_OPT_STR

 diff --git a/kexec/arch/s390/kexec-image.c b/kexec/arch/s390/kexec-image.c

 index 209ab77ddccbd60f10989e2d9fc273324aefa76d..69aaf96812f741110bf323b4bb8d5dda155f293a 100644

 --- a/kexec/arch/s390/kexec-image.c

 +++ b/kexec/arch/s390/kexec-image.c

 @@ -71,6 +71,10 @@ int image_s390_load_file(int argc, char **argv, struct kexec_info *info)

  		case OPT_RAMDISK:

  			ramdisk = optarg;

  			break;

 +		case OPT_REUSE_CMDLINE:

 +			free(info->command_line);

 +			info->command_line = get_command_line();

 +			break;

  		}

  	}

 @@ -123,6 +127,10 @@ image_s390_load(int argc, char **argv, const char *kernel_buf,

  			if (command_line_add(info, optarg))

  				return -1;

  			break;

 +		case OPT_REUSE_CMDLINE:

 +			free(info->command_line);

 +			info->command_line = get_command_line();

 +			break;

  		case OPT_RAMDISK:

  			ramdisk = optarg;

  			break;

 @@ -223,5 +231,6 @@ image_s390_usage(void)

  	printf("--command-line=STRING Set the kernel command line to STRING.\n"

  	       "--append=STRING       Set the kernel command line to STRING.\n"

  	       "--initrd=FILENAME     Use the file FILENAME as a ramdisk.\n"

 +	       "--reuse-cmdline       Use kernel command line from running system.\n"

  		);

  }