Add --reuse-cmdline

This patch adds an option "--reuse-cmdline" for people that are lazy in typing --append="$(cat /proc/cmdline)". The advantage of "--reuse-cmdline" is also that it strips off BOOT_IMAGE (since it may not be correct any more) from lilo and other boot loaders, and, more important, the crashkernel option in case a panic kernel is loaded.

If you like the option I can also add it for really all architectures. Tested only with x86-bzImage both the kexec and kdump case.

Signed-off-by Bernhard Walle <[email protected]>

---
 kexec/arch/i386/kexec-bzImage.c       |   12 +++-
 kexec/arch/i386/kexec-elf-x86.c       |   16 ++++--
 kexec/arch/i386/kexec-multiboot-x86.c |   12 +++-
 kexec/arch/x86_64/kexec-elf-x86_64.c  |   16 ++++--
 kexec/kexec.8                         |   18 +++++++
 kexec/kexec.c                         |   85 +++++++++++++++++++++++++++++-----
 kexec/kexec.h                         |    1 
 7 files changed, 132 insertions(+), 28 deletions(-)

kexec/arch/i386/kexec-bzImage.c +9 -3

@@ -89,6 +89,7 @@ void bzImage_usage(void)
 		"    --real-mode           Use the kernels real mode entry point.\n"
 		"    --command-line=STRING Set the kernel command line to STRING.\n"
 		"    --append=STRING       Set the kernel command line to STRING.\n"
+		"    --reuse-cmdline       Use kernel command line from running system.\n"
 		"    --initrd=FILE         Use FILE as the kernel's initial ramdisk.\n"
 		"    --ramdisk=FILE        Use FILE as the kernel's initial ramdisk.\n"
 		);

@@ -335,14 +336,16 @@ int bzImage_load(int argc, char **argv,
 	int debug, real_mode_entry;
 	int opt;
 	int result;
-#define OPT_APPEND	(OPT_ARCH_MAX+0)
-#define OPT_RAMDISK	(OPT_ARCH_MAX+1)
-#define OPT_REAL_MODE	(OPT_ARCH_MAX+2)
+#define OPT_APPEND		(OPT_ARCH_MAX+0)
+#define OPT_REUSE_CMDLINE	(OPT_ARCH_MAX+1)
+#define OPT_RAMDISK		(OPT_ARCH_MAX+2)
+#define OPT_REAL_MODE		(OPT_ARCH_MAX+3)
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "debug",		0, 0, OPT_DEBUG },
 		{ "command-line",	1, 0, OPT_APPEND },
 		{ "append",		1, 0, OPT_APPEND },
+		{ "reuse-cmdline",	1, 0, OPT_REUSE_CMDLINE },
 		{ "initrd",		1, 0, OPT_RAMDISK },
 		{ "ramdisk",		1, 0, OPT_RAMDISK },
 		{ "real-mode",		0, 0, OPT_REAL_MODE },

@@ -374,6 +377,9 @@ int bzImage_load(int argc, char **argv,
 		case OPT_APPEND:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_RAMDISK:
 			ramdisk = optarg;
 			break;

kexec/arch/i386/kexec-elf-x86.c +11 -5

@@ -73,6 +73,7 @@ void elf_x86_usage(void)
 {
 	printf(	"    --command-line=STRING Set the kernel command line to STRING\n"
 		"    --append=STRING       Set the kernel command line to STRING\n"
+		"    --reuse-cmdline       Use kernel command line from running system.\n"
 		"    --initrd=FILE         Use FILE as the kernel's initial ramdisk.\n"
 		"    --ramdisk=FILE        Use FILE as the kernel's initial ramdisk.\n"
 		"    --args-linux          Pass linux kernel style options\n"

@@ -97,16 +98,18 @@ int elf_x86_load(int argc, char **argv,
 #define ARG_STYLE_LINUX 1
 #define ARG_STYLE_NONE  2
 	int opt;
-#define OPT_APPEND	(OPT_ARCH_MAX+0)
-#define OPT_RAMDISK	(OPT_ARCH_MAX+1)
-#define OPT_ARGS_ELF    (OPT_ARCH_MAX+2)
-#define OPT_ARGS_LINUX  (OPT_ARCH_MAX+3)
-#define OPT_ARGS_NONE   (OPT_ARCH_MAX+4)
+#define OPT_APPEND		(OPT_ARCH_MAX+0)
+#define OPT_REUSE_CMDLINE	(OPT_ARCH_MAX+1)
+#define OPT_RAMDISK		(OPT_ARCH_MAX+2)
+#define OPT_ARGS_ELF    	(OPT_ARCH_MAX+3)
+#define OPT_ARGS_LINUX  	(OPT_ARCH_MAX+4)
+#define OPT_ARGS_NONE   	(OPT_ARCH_MAX+5)
 
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "command-line",	1, NULL, OPT_APPEND },
 		{ "append",		1, NULL, OPT_APPEND },
+		{ "reuse-cmdline",	1, NULL, OPT_REUSE_CMDLINE },
 		{ "initrd",		1, NULL, OPT_RAMDISK },
 		{ "ramdisk",		1, NULL, OPT_RAMDISK },
 		{ "args-elf",		0, NULL, OPT_ARGS_ELF },

@@ -138,6 +141,9 @@ int elf_x86_load(int argc, char **argv,
 		case OPT_APPEND:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_RAMDISK:
 			ramdisk = optarg;
 			break;

kexec/arch/i386/kexec-multiboot-x86.c +9 -3

@@ -129,6 +129,7 @@ void multiboot_x86_usage(void)
 /* Multiboot-specific options */
 {
 	printf("    --command-line=STRING        Set the kernel command line to STRING.\n");
+	printf("    --reuse-cmdline       	 Use kernel command line from running system.\n");
 	printf("    --module=\"MOD arg1 arg2...\"  Load module MOD with command-line \"arg1...\"\n");
 	printf("                                 (can be used multiple times).\n");
 }

@@ -155,13 +156,15 @@ int multiboot_x86_load(int argc, char **
 	int i;
 	int opt;
 	int modules, mod_command_line_space;
-#define OPT_CL  	(OPT_ARCH_MAX+0)
-#define OPT_MOD 	(OPT_ARCH_MAX+1)
-#define OPT_VGA 	(OPT_ARCH_MAX+2)
+#define OPT_CL  		(OPT_ARCH_MAX+0)
+#define OPT_REUSE_CMDLINE	(OPT_ARCH_MAX+1)
+#define OPT_MOD 		(OPT_ARCH_MAX+2)
+#define OPT_VGA 		(OPT_ARCH_MAX+3)
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "command-line",		1, 0, OPT_CL },
 		{ "append",			1, 0, OPT_CL },
+		{ "reuse-cmdline",		1, 0, OPT_REUSE_CMDLINE },
 		{ "module",			1, 0, OPT_MOD },
 		{ 0, 				0, 0, 0 },
 	};

@@ -194,6 +197,9 @@ int multiboot_x86_load(int argc, char **
 		case OPT_CL:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_MOD:
 			modules++;
 			mod_command_line_space += strlen(optarg) + 1;

kexec/arch/x86_64/kexec-elf-x86_64.c +11 -5

@@ -73,6 +73,7 @@ void elf_x86_64_usage(void)
 {
 	printf(	"    --command-line=STRING Set the kernel command line to STRING\n"
 		"    --append=STRING       Set the kernel command line to STRING\n"
+		"    --reuse-cmdline       Use kernel command line from running system.\n"
 		"    --initrd=FILE         Use FILE as the kernel's initial ramdisk.\n"
 		"    --ramdisk=FILE        Use FILE as the kernel's initial ramdisk.\n"
 		"    --args-linux          Pass linux kernel style options\n"

@@ -96,16 +97,18 @@ int elf_x86_64_load(int argc, char **arg
 #define ARG_STYLE_LINUX 1
 #define ARG_STYLE_NONE  2
 	int opt;
-#define OPT_APPEND	(OPT_ARCH_MAX+0)
-#define OPT_RAMDISK	(OPT_ARCH_MAX+1)
-#define OPT_ARGS_ELF    (OPT_ARCH_MAX+2)
-#define OPT_ARGS_LINUX  (OPT_ARCH_MAX+3)
-#define OPT_ARGS_NONE   (OPT_ARCH_MAX+4)
+#define OPT_APPEND		(OPT_ARCH_MAX+0)
+#define OPT_REUSE_CMDLINE	(OPT_ARCH_MAX+1)
+#define OPT_RAMDISK		(OPT_ARCH_MAX+2)
+#define OPT_ARGS_ELF		(OPT_ARCH_MAX+3)
+#define OPT_ARGS_LINUX		(OPT_ARCH_MAX+4)
+#define OPT_ARGS_NONE		(OPT_ARCH_MAX+5)
 
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "command-line",	1, NULL, OPT_APPEND },
 		{ "append",		1, NULL, OPT_APPEND },
+		{ "reuse-cmdline",	1, NULL, OPT_REUSE_CMDLINE },
 		{ "initrd",		1, NULL, OPT_RAMDISK },
 		{ "ramdisk",		1, NULL, OPT_RAMDISK },
 		{ "args-elf",		0, NULL, OPT_ARGS_ELF },

@@ -138,6 +141,9 @@ int elf_x86_64_load(int argc, char **arg
 		case OPT_APPEND:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_RAMDISK:
 			ramdisk = optarg;
 			break;

kexec/kexec.8 +18 -0

@@ -186,6 +186,15 @@ to the kernel command line.
 Set the kernel command line to
 .IR string .
 .TP
+.BI \-\-reuse-cmdline
+Use the command line from the running system. When a panic kernel is loaded, it
+strips the
+.I
+crashkernel
+parameter automatically. The
+.I BOOT_IMAGE
+parameter is also stripped.
+.TP
 .BI \-\-initrd= file
 Use
 .I file

@@ -204,6 +213,15 @@ as the kernel's initial ramdisk.
 Set the kernel command line to
 .IR string .
 .TP
+.BI \-\-reuse-cmdline
+Use the command line from the running system. When a panic kernel is loaded, it
+strips the
+.I
+crashkernel
+parameter automatically. The
+.I BOOT_IMAGE
+parameter is also stripped.
+.TP
 .BI \-\-module= "mod arg1 arg2 ..."
 Load module
 .I mod

kexec/kexec.c +73 -12

@@ -31,6 +31,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <getopt.h>
+#include <ctype.h>
 
 #include "config.h"
 

@@ -46,6 +47,7 @@
 
 unsigned long long mem_min = 0;
 unsigned long long mem_max = ULONG_MAX;
+unsigned long kexec_flags = 0;
 
 void die(char *fmt, ...)
 {

@@ -792,26 +794,86 @@ static int kexec_loaded(void)
 	return ret;
 }
 
+/*
+ * Remove parameter from a kernel command line. Helper function by get_command_line().
+ */
+static void remove_parameter(char *line, const char *param_name)
+{
+	char *start, *end;
+
+	start = strstr(line, param_name);
+
+	/* parameter not found */
+	if (!start)
+		return;
+
+	/*
+	 * check if that's really the start of a parameter and not in
+	 * the middle of the word
+	 */
+	if (start != line && !isspace(*(start-1)))
+		return;
+
+	end = strstr(start, " ");
+	if (!end)
+		*start = 0;
+	else {
+		memmove(start, end+1, strlen(end));
+		*(end + strlen(end)) = 0;
+	}
+}
+
+/*
+ * Returns the contents of the current command line to be used with
+ * --reuse-cmdline option.  The function gets called from architecture specific
+ * code. If we load a panic kernel, that function will strip the
+ * "crashkernel=" option because it does not make sense that the crashkernel
+ * reserves memory for a crashkernel (well, it would not boot since the
+ * amount is exactly the same as the crashkernel has overall memory). Also,
+ * remove the BOOT_IMAGE from lilo (and others) since that doesn't make
+ * sense here any more. The kernel could be different even if we reuse the
+ * commandline.
+ *
+ * The function returns dynamically allocated memory.
+ */
+char *get_command_line(void)
+{
+	FILE *fp;
+	size_t len;
+	char *line = NULL;
+
+	fp = fopen("/proc/cmdline", "r");
+	if (!fp)
+		die("Could not read /proc/cmdline.");
+	getline(&line, &len, fp);
+	fclose(fp);
+
+	if (line) {
+		/* strip newline */
+		*(line + strlen(line) - 1) = 0;
+
+		remove_parameter(line, "crashkernel");
+		if (kexec_flags & KEXEC_ON_CRASH)
+			remove_parameter(line, "BOOT_IMAGE");
+	} else
+		line = strdup("");
+
+	return line;
+}
+
 /* check we retained the initrd */
 void check_reuse_initrd(void)
 {
-	FILE * fp;
-	char * line = NULL;
-	size_t len = 0;
-	ssize_t read;
+	char *line = get_command_line();
 
-	fp = fopen("/proc/cmdline", "r");
-	if (fp == NULL)
-		die("unable to open /proc/cmdline\n");
-	read = getline(&line, &len, fp);
 	if (strstr(line, "retain_initrd") == NULL)
 		die("unrecoverable error: current boot didn't "
 		    "retain the initrd for reuse.\n");
-	if (line)
-		free(line);
-	fclose(fp);
+
+	free(line);
 }
 
+
 int main(int argc, char *argv[])
 {
 	int do_load = 1;

@@ -821,7 +883,6 @@ int main(int argc, char *argv[])
 	int do_ifdown = 0;
 	int do_unload = 0;
 	int do_reuse_initrd = 0;
-	unsigned long kexec_flags = 0;
 	char *type = 0;
 	char *endptr;
 	int opt;

kexec/kexec.h +1 -0

@@ -220,6 +220,7 @@ int arch_process_options(int argc, char
 int arch_compat_trampoline(struct kexec_info *info);
 void arch_update_purgatory(struct kexec_info *info);
 int is_crashkernel_mem_reserved(void);
+char *get_command_line(void);
 
 int kexec_iomem_for_each_line(char *match,
 			      int (*callback)(void *data,

_______________________________________________
kexec mailing list
[email protected]
http://lists.infradead.org/mailman/listinfo/kexec

This patch adds an option "--reuse-cmdline" for people that are lazy in typin

--append="$(cat /proc/cmdline)". The advantage of "--reuse-cmdline" is also t

it strips off BOOT_IMAGE (since it may not be correct any more) from lilo and other boot loaders, and, more important, the crashkernel option in case a panic kernel is loaded.

If you like the option I can also add it for really all architectures. Tested

with x86-bzImage both the kexec and kdump case.

Signed-off-by Bernhard Walle <[email protected]>

---
 kexec/arch/i386/kexec-bzImage.c       |   12 +++-
 kexec/arch/i386/kexec-elf-x86.c       |   16 ++++--
 kexec/arch/i386/kexec-multiboot-x86.c |   12 +++-
 kexec/arch/x86_64/kexec-elf-x86_64.c  |   16 ++++--
 kexec/kexec.8                         |   18 +++++++
 kexec/kexec.c                         |   85 +++++++++++++++++++++++++++++--

kexec/arch/i386/kexec-bzImage.c +4 -0

 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "debug",		0, 0, OPT_DEBUG },
 		{ "command-line",	1, 0, OPT_APPEND },
 		{ "append",		1, 0, OPT_APPEND },
+		{ "reuse-cmdline",	1, 0, OPT_REUSE_CMDLINE },
 		{ "initrd",		1, 0, OPT_RAMDISK },
 		{ "ramdisk",		1, 0, OPT_RAMDISK },
 		{ "real-mode",		0, 0, OPT_REAL_MODE },

@@ -374,6 +377,9 @@ int bzImage_load(int argc, char **argv,
 		case OPT_APPEND:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_RAMDISK:
 			ramdisk = optarg;
 			break;

kexec/arch/i386/kexec-elf-x86.c +10 -5

 		"    --args-linux          Pass linux kernel style options\n"

@@ -97,16 +98,18 @@ int elf_x86_load(int argc, char **argv,
 #define ARG_STYLE_LINUX 1
 #define ARG_STYLE_NONE  2
 	int opt;
-#define OPT_APPEND	(OPT_ARCH_MAX+0)
-#define OPT_RAMDISK	(OPT_ARCH_MAX+1)
-#define OPT_ARGS_ELF    (OPT_ARCH_MAX+2)
-#define OPT_ARGS_LINUX  (OPT_ARCH_MAX+3)
-#define OPT_ARGS_NONE   (OPT_ARCH_MAX+4)
+#define OPT_APPEND		(OPT_ARCH_MAX+0)
+#define OPT_REUSE_CMDLINE	(OPT_ARCH_MAX+1)
+#define OPT_RAMDISK		(OPT_ARCH_MAX+2)
+#define OPT_ARGS_ELF    	(OPT_ARCH_MAX+3)
+#define OPT_ARGS_LINUX  	(OPT_ARCH_MAX+4)
+#define OPT_ARGS_NONE   	(OPT_ARCH_MAX+5)
 
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "command-line",	1, NULL, OPT_APPEND },
 		{ "append",		1, NULL, OPT_APPEND },
+		{ "reuse-cmdline",	1, NULL, OPT_REUSE_CMDLINE },
 		{ "initrd",		1, NULL, OPT_RAMDISK },
 		{ "ramdisk",		1, NULL, OPT_RAMDISK },
 		{ "args-elf",		0, NULL, OPT_ARGS_ELF },

@@ -138,6 +141,9 @@ int elf_x86_load(int argc, char **argv,
 		case OPT_APPEND:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_RAMDISK:
 			ramdisk = optarg;
 			break;

kexec/arch/i386/kexec-multiboot-x86.c +8 -3

 }

@@ -155,13 +156,15 @@ int multiboot_x86_load(int argc, char **
 	int i;
 	int opt;
 	int modules, mod_command_line_space;
-#define OPT_CL  	(OPT_ARCH_MAX+0)
-#define OPT_MOD 	(OPT_ARCH_MAX+1)
-#define OPT_VGA 	(OPT_ARCH_MAX+2)
+#define OPT_CL  		(OPT_ARCH_MAX+0)
+#define OPT_REUSE_CMDLINE	(OPT_ARCH_MAX+1)
+#define OPT_MOD 		(OPT_ARCH_MAX+2)
+#define OPT_VGA 		(OPT_ARCH_MAX+3)
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "command-line",		1, 0, OPT_CL },
 		{ "append",			1, 0, OPT_CL },
+		{ "reuse-cmdline",		1, 0, OPT_REUSE_CMDLINE },
 		{ "module",			1, 0, OPT_MOD },
 		{ 0, 				0, 0, 0 },
 	};

@@ -194,6 +197,9 @@ int multiboot_x86_load(int argc, char **
 		case OPT_CL:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_MOD:
 			modules++;
 			mod_command_line_space += strlen(optarg) + 1;

kexec/arch/x86_64/kexec-elf-x86_64.c +10 -5

 		"    --args-linux          Pass linux kernel style options\n"

@@ -96,16 +97,18 @@ int elf_x86_64_load(int argc, char **arg
 #define ARG_STYLE_LINUX 1
 #define ARG_STYLE_NONE  2
 	int opt;
-#define OPT_APPEND	(OPT_ARCH_MAX+0)
-#define OPT_RAMDISK	(OPT_ARCH_MAX+1)
-#define OPT_ARGS_ELF    (OPT_ARCH_MAX+2)
-#define OPT_ARGS_LINUX  (OPT_ARCH_MAX+3)
-#define OPT_ARGS_NONE   (OPT_ARCH_MAX+4)
+#define OPT_APPEND		(OPT_ARCH_MAX+0)
+#define OPT_REUSE_CMDLINE	(OPT_ARCH_MAX+1)
+#define OPT_RAMDISK		(OPT_ARCH_MAX+2)
+#define OPT_ARGS_ELF		(OPT_ARCH_MAX+3)
+#define OPT_ARGS_LINUX		(OPT_ARCH_MAX+4)
+#define OPT_ARGS_NONE		(OPT_ARCH_MAX+5)
 
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
 		{ "command-line",	1, NULL, OPT_APPEND },
 		{ "append",		1, NULL, OPT_APPEND },
+		{ "reuse-cmdline",	1, NULL, OPT_REUSE_CMDLINE },
 		{ "initrd",		1, NULL, OPT_RAMDISK },
 		{ "ramdisk",		1, NULL, OPT_RAMDISK },
 		{ "args-elf",		0, NULL, OPT_ARGS_ELF },

@@ -138,6 +141,9 @@ int elf_x86_64_load(int argc, char **arg
 		case OPT_APPEND:
 			command_line = optarg;
 			break;
+		case OPT_REUSE_CMDLINE:
+			command_line = get_command_line();
+			break;
 		case OPT_RAMDISK:
 			ramdisk = optarg;
 			break;

kexec/kexec.8 +7 -0

+strips the
+.I
+crashkernel
+parameter automatically. The
+.I BOOT_IMAGE
+parameter is also stripped.
+.TP
 .BI \-\-initrd= file
 Use
 .I file

kexec/kexec.8 +7 -0

+strips the
+.I
+crashkernel
+parameter automatically. The
+.I BOOT_IMAGE
+parameter is also stripped.
+.TP
 .BI \-\-module= "mod arg1 arg2 ..."
 Load module
 .I mod

kexec/kexec.c +2 -0

@@ -31,6 +31,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <getopt.h>
+#include <ctype.h>
 
 #include "config.h"
 

@@ -46,6 +47,7 @@
 
 unsigned long long mem_min = 0;
 unsigned long long mem_max = ULONG_MAX;
+unsigned long kexec_flags = 0;
 
 void die(char *fmt, ...)
 {

kexec/kexec.c +20 -0

+ */
+static void remove_parameter(char *line, const char *param_name)
+{
+	char *start, *end;
+
+	start = strstr(line, param_name);
+
+	/* parameter not found */
+	if (!start)
+		return;
+
+	/*
+	 * check if that's really the start of a parameter and not in
+	 * the middle of the word
+	 */
+	if (start != line && !isspace(*(start-1)))
+		return;
+
+	end = strstr(start, " ");
+	if (!end)

kexec/kexec.c +39 -12

+ * code. If we load a panic kernel, that function will strip the
+ * "crashkernel=" option because it does not make sense that the crashkernel
+ * reserves memory for a crashkernel (well, it would not boot since the
+ * amount is exactly the same as the crashkernel has overall memory). Also,
+ * remove the BOOT_IMAGE from lilo (and others) since that doesn't make
+ * sense here any more. The kernel could be different even if we reuse the
+ * commandline.
+ *
+ * The function returns dynamically allocated memory.
+ */
+char *get_command_line(void)
+{
+	FILE *fp;
+	size_t len;
+	char *line = NULL;
+
+	fp = fopen("/proc/cmdline", "r");
+	if (!fp)
+		die("Could not read /proc/cmdline.");
+	getline(&line, &len, fp);
+	fclose(fp);
+
+	if (line) {
+		/* strip newline */
+		*(line + strlen(line) - 1) = 0;
+
+		remove_parameter(line, "crashkernel");
+		if (kexec_flags & KEXEC_ON_CRASH)
+			remove_parameter(line, "BOOT_IMAGE");
+	} else
+		line = strdup("");
+
+	return line;
+}
+
 /* check we retained the initrd */
 void check_reuse_initrd(void)
 {
-	FILE * fp;
-	char * line = NULL;
-	size_t len = 0;
-	ssize_t read;
+	char *line = get_command_line();
 
-	fp = fopen("/proc/cmdline", "r");
-	if (fp == NULL)
-		die("unable to open /proc/cmdline\n");
-	read = getline(&line, &len, fp);
 	if (strstr(line, "retain_initrd") == NULL)
 		die("unrecoverable error: current boot didn't "
 		    "retain the initrd for reuse.\n");
-	if (line)
-		free(line);
-	fclose(fp);
+
+	free(line);
 }
 
+
 int main(int argc, char *argv[])
 {
 	int do_load = 1;

@@ -821,7 +883,6 @@ int main(int argc, char *argv[])
 	int do_ifdown = 0;
 	int do_unload = 0;
 	int do_reuse_initrd = 0;
-	unsigned long kexec_flags = 0;
 	char *type = 0;
 	char *endptr;
 	int opt;

kexec/kexec.h +1 -0

@@ -220,6 +220,7 @@ int arch_process_options(int argc, char
 int arch_compat_trampoline(struct kexec_info *info);
 void arch_update_purgatory(struct kexec_info *info);
 int is_crashkernel_mem_reserved(void);
+char *get_command_line(void);
 
 int kexec_iomem_for_each_line(char *match,
 			      int (*callback)(void *data,

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Quoted 1 line · In message <[email protected]> you wrote:

This patch adds an option "--reuse-cmdline" for people that are lazy in typin

g

Quoted 1 line

--append="$(cat /proc/cmdline)". The advantage of "--reuse-cmdline" is also t

hat

Quoted 4 lines

it strips off BOOT_IMAGE (since it may not be correct any more) from lilo and other boot loaders, and, more important, the crashkernel option in case a panic kernel is loaded.

Quoted 1 line

If you like the option I can also add it for really all architectures. Tested

only

Quoted 1 line

with x86-bzImage both the kexec and kdump case.

For ppc64, the default is to reuse the command line. We should probably merge functionality.

Either way, this should probably be a generic option, not x86 specific.

--Sig_/XVYJV.ZkU.f5R3y3b_UR6.k
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: quoted-printable

Hi,

at first thanks for looking at the patch.

Quoted 3 lines · Michael Neuling

=20

Quoted 1 line · In message <[email protected]> you wrote:

This patch adds an option "--reuse-cmdline" for people that are lazy in=

typin

Quoted 2 lines

g

Quoted 1 line

--append=3D"$(cat /proc/cmdline)". The advantage of "--reuse-cmdline" i=

s also t

Quoted 2 lines

hat

Quoted 1 line

it strips off BOOT_IMAGE (since it may not be correct any more) from li=

lo and

Quoted 1 line

Quoted 1 line

other boot loaders, and, more important, the crashkernel option in case=

a

Quoted 3 lines

Quoted 3 lines

panic kernel is loaded.
=20
If you like the option I can also add it for really all architectures. =

Tested

Quoted 1 line

only

Quoted 4 lines

Quoted 1 line

with x86-bzImage both the kexec and kdump case.

=20
For ppc64, the default is to reuse the command line. We should probably merge functionality.

Where is that functionality implemented? I couldn't find it. Does the kernel that automatically on PPC64? I know too litte about that architecture.

Quoted 1 line

Either way, this should probably be a generic option, not x86 specific.

Well, I thought first of it. But since the '--append' parameter is not generic, this makes no sense.

Maybe it would make sense to change the command line handling in general to be global and not image specific, but first I need to understand how that works on PPC64 ... (and probably others).

In message <[email protected]> you wrote:

Sorry, I think I was mistaken. ppc64 only takes the "root=<blah>" from the first kernel, provided it's not specified on the kexec command line for the next kernel.

Anyway, the code is in kexec/arch/ppc64/fs2dt.c (search for "root=")

Quoted 8 lines

Quoted 1 line

Either way, this should probably be a generic option, not x86 specific.

Well, I thought first of it. But since the '--append' parameter is not generic, this makes no sense.

Maybe it would make sense to change the command line handling in general to be global and not image specific, but first I need to understand how that works on PPC64 ... (and probably others).

Yeah, the cmdline should be generically and consistently handled rather than what we have now.

The problem is that not all boot options are always usable in the next kernel, in addition to being architecturally specific, it's very situational. Having written that, a generic framework could be usable.