Bring powerpc in line with other architectures that support extending or
overriding the bootloader provided command line.
The current behaviour is most like CMDLINE_FROM_BOOTLOADER where the
bootloader command line is preferred but the kernel config can provide a
fallback so CMDLINE_FROM_BOOTLOADER is the default. CMDLINE_EXTEND can
be used to append the CMDLINE from the kernel config to the one provided
by the bootloader.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
---
While I'm at it does anyone think it's worth getting rid of the default CMDLINE
value if CMDLINE_BOOL and maybe CMDLINE_BOOL? Every defconfig in the kernel
that sets CMDLINE_BOOL=y also sets CMDLINE to something other than
"console=ttyS0,9600 console=tty0 root=/dev/sda2". Removing CMDLINE_BOOL and
unconditionally setting the default value of CMDLINE to "" would clean up the
Kconfig even more.
Changes in v2:
- incorporate ideas from Christope's patch https://patchwork.ozlabs.org/patch/1074126/
arch/powerpc/Kconfig | 20 +++++++++++++++++++-
arch/powerpc/kernel/prom_init.c | 26 +++++++++++++++++++++++++-
2 files changed, 44 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 77f6ebf97113..d413fe1b4058 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -852,15 +852,33 @@ config CMDLINE
some command-line options at build time by entering them here. In
most cases you will need to specify the root device here.
+choice
+ prompt "Kernel command line type" if CMDLINE != ""
+ default CMDLINE_FROM_BOOTLOADER
+
+config CMDLINE_FROM_BOOTLOADER
+ bool "Use bootloader kernel arguments if available"
+ help
+ Uses the command-line options passed by the boot loader. If
+ the boot loader doesn't provide any, the default kernel command
+ string provided in CMDLINE will be used.
+
+config CMDLINE_EXTEND
+ bool "Extend bootloader kernel arguments"
+ help
+ The command-line arguments provided by the boot loader will be
+ appended to the default kernel command string.
+
config CMDLINE_FORCE
bool "Always use the default kernel command string"
- depends on CMDLINE_BOOL
help
Always use the default kernel command string, even if the boot
loader passes other arguments to the kernel.
This is useful if you cannot or don't want to change the
command-line options your boot loader passes to the kernel.
+endchoice
+
config EXTRA_TARGETS
string "Additional default image types"
help
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 514707ef6779..df29f141dbd2 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -310,6 +310,25 @@ static size_t __init prom_strlcpy(char *dest, const char *src, size_t size)
return ret;
}
+static size_t __init prom_strlcat(char *dest, const char *src, size_t count)
+{
+ size_t dsize = prom_strlen(dest);
+ size_t len = prom_strlen(src);
+ size_t res = dsize + len;
+
+ /* This would be a bug */
+ BUG_ON(dsize >= count);
+
+ dest += dsize;
+ count -= dsize;
+ if (len >= count)
+ len = count-1;
+ memcpy(dest, src, len);
+ dest[len] = 0;
+ return res;
+
+}
+
#ifdef CONFIG_PPC_PSERIES
static int __init prom_strtobool(const char *s, bool *res)
{@@ -761,8 +780,13 @@ static void __init early_cmdline_parse(void)
p = prom_cmd_line;
if ((long)prom.chosen > 0)
l = prom_getprop(prom.chosen, "bootargs", p, COMMAND_LINE_SIZE-1);
- if (IS_ENABLED(CONFIG_CMDLINE_BOOL) && (l <= 0 || p[0] == '\0')) /* dbl check */
+
+ if (IS_ENABLED(CONFIG_CMDLINE_FORCE) || l <= 0 || p[0] == '\0')
prom_strlcpy(prom_cmd_line, CONFIG_CMDLINE, sizeof(prom_cmd_line));
+ else if (IS_ENABLED(CONFIG_CMDLINE_EXTEND))
+ prom_strlcat(prom_cmd_line, " " CONFIG_CMDLINE,
+ sizeof(prom_cmd_line));
+
prom_printf("command line: %s\n", prom_cmd_line);
#ifdef CONFIG_PPC64--
2.22.0
Le 01/08/2019 à 04:12, Chris Packham a écrit :
Bring powerpc in line with other architectures that support extending or
overriding the bootloader provided command line.
The current behaviour is most like CMDLINE_FROM_BOOTLOADER where the
bootloader command line is preferred but the kernel config can provide a
fallback so CMDLINE_FROM_BOOTLOADER is the default. CMDLINE_EXTEND can
be used to append the CMDLINE from the kernel config to the one provided
by the bootloader.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
---
While I'm at it does anyone think it's worth getting rid of the default CMDLINE
value if CMDLINE_BOOL and maybe CMDLINE_BOOL? Every defconfig in the kernel
that sets CMDLINE_BOOL=y also sets CMDLINE to something other than
"console=ttyS0,9600 console=tty0 root=/dev/sda2". Removing CMDLINE_BOOL and
unconditionally setting the default value of CMDLINE to "" would clean up the
Kconfig even more.
Note
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cbe46bd4f5104552b612505b73d366f66efc2341
which is already a step forward.
I guess that default is for users selecting this option manually to get
a first sensitive CMDLINE. But is it really worth it ?
quoted hunk
Changes in v2:
- incorporate ideas from Christope's patch https://patchwork.ozlabs.org/patch/1074126/
arch/powerpc/Kconfig | 20 +++++++++++++++++++-
arch/powerpc/kernel/prom_init.c | 26 +++++++++++++++++++++++++-
2 files changed, 44 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 77f6ebf97113..d413fe1b4058 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -852,15 +852,33 @@ config CMDLINE
some command-line options at build time by entering them here. In
most cases you will need to specify the root device here.
+choice
+ prompt "Kernel command line type" if CMDLINE != ""
+ default CMDLINE_FROM_BOOTLOADER
+
+config CMDLINE_FROM_BOOTLOADER
+ bool "Use bootloader kernel arguments if available"
+ help
+ Uses the command-line options passed by the boot loader. If
+ the boot loader doesn't provide any, the default kernel command
+ string provided in CMDLINE will be used.
+
+config CMDLINE_EXTEND
+ bool "Extend bootloader kernel arguments"
+ help
+ The command-line arguments provided by the boot loader will be
+ appended to the default kernel command string.
+
config CMDLINE_FORCE
bool "Always use the default kernel command string"
- depends on CMDLINE_BOOL
help
Always use the default kernel command string, even if the boot
loader passes other arguments to the kernel.
This is useful if you cannot or don't want to change the
command-line options your boot loader passes to the kernel.
+endchoice
+
config EXTRA_TARGETS
string "Additional default image types"
help
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 514707ef6779..df29f141dbd2 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -310,6 +310,25 @@ static size_t __init prom_strlcpy(char *dest, const char *src, size_t size)
return ret;
}
+static size_t __init prom_strlcat(char *dest, const char *src, size_t count)
+{
+ size_t dsize = prom_strlen(dest);
+ size_t len = prom_strlen(src);
+ size_t res = dsize + len;
+
+ /* This would be a bug */
+ BUG_ON(dsize >= count);
Has you pointed in another mail, BUG_ON() should be avoided here.
I guess if the destination is already full, just return count:
if (dsize >= count)
return count;
quoted hunk
+
+ dest += dsize;
+ count -= dsize;
+ if (len >= count)
+ len = count-1;
+ memcpy(dest, src, len);
+ dest[len] = 0;
+ return res;
+
+}
+
#ifdef CONFIG_PPC_PSERIES
static int __init prom_strtobool(const char *s, bool *res)
{@@ -761,8 +780,13 @@ static void __init early_cmdline_parse(void)
p = prom_cmd_line;
if ((long)prom.chosen > 0)
l = prom_getprop(prom.chosen, "bootargs", p, COMMAND_LINE_SIZE-1);
The above is pointless in case CONFIG_CMDLINE_FORCE is selected.
- if (IS_ENABLED(CONFIG_CMDLINE_BOOL) && (l <= 0 || p[0] == '\0')) /* dbl check */
+
+ if (IS_ENABLED(CONFIG_CMDLINE_FORCE) || l <= 0 || p[0] == '\0')
prom_strlcpy(prom_cmd_line, CONFIG_CMDLINE, sizeof(prom_cmd_line));
If we can ensure that prom_cmd_line remains empty when
CONFIG_CMDLINE_FORCE is selected (see above comment), then
prom_strlcat() can be used in lieu of prom_strlcpy()
+ else if (IS_ENABLED(CONFIG_CMDLINE_EXTEND))
+ prom_strlcat(prom_cmd_line, " " CONFIG_CMDLINE,
+ sizeof(prom_cmd_line));
+
prom_printf("command line: %s\n", prom_cmd_line);
#ifdef CONFIG_PPC64
Christophe
On Thu, 2019-08-01 at 08:14 +0200, Christophe Leroy wrote:
Le 01/08/2019 à 04:12, Chris Packham a écrit :
quoted
Bring powerpc in line with other architectures that support
extending or
overriding the bootloader provided command line.
The current behaviour is most like CMDLINE_FROM_BOOTLOADER where
the
bootloader command line is preferred but the kernel config can
provide a
fallback so CMDLINE_FROM_BOOTLOADER is the default. CMDLINE_EXTEND
can
be used to append the CMDLINE from the kernel config to the one
provided
by the bootloader.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
---
While I'm at it does anyone think it's worth getting rid of the
default CMDLINE
value if CMDLINE_BOOL and maybe CMDLINE_BOOL? Every defconfig in
the kernel
that sets CMDLINE_BOOL=y also sets CMDLINE to something other than
"console=ttyS0,9600 console=tty0 root=/dev/sda2". Removing
CMDLINE_BOOL and
unconditionally setting the default value of CMDLINE to "" would
clean up the
Kconfig even more.
Note
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/co
mmit/?id=cbe46bd4f5104552b612505b73d366f66efc2341
which is already a step forward.
I guess that default is for users selecting this option manually to
get
a first sensitive CMDLINE. But is it really worth it ?
I'm not even sure if it is working as intended right now. Even without
my changes if I use menuconfig and select CMDLINE_BOOL I end up with
CONFIG_CMDLINE="" in the resulting .config.
quoted
Changes in v2:
- incorporate ideas from Christope's patch https://patchwork.ozlabs
.org/patch/1074126/
arch/powerpc/Kconfig | 20 +++++++++++++++++++-
arch/powerpc/kernel/prom_init.c | 26 +++++++++++++++++++++++++-
2 files changed, 44 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 77f6ebf97113..d413fe1b4058 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -852,15 +852,33 @@ config CMDLINE
some command-line options at build time by entering
them here. In
most cases you will need to specify the root device
here.
+choice
+ prompt "Kernel command line type" if CMDLINE != ""
+ default CMDLINE_FROM_BOOTLOADER
+
+config CMDLINE_FROM_BOOTLOADER
+ bool "Use bootloader kernel arguments if available"
+ help
+ Uses the command-line options passed by the boot loader.
If
+ the boot loader doesn't provide any, the default kernel
command
+ string provided in CMDLINE will be used.
+
+config CMDLINE_EXTEND
+ bool "Extend bootloader kernel arguments"
+ help
+ The command-line arguments provided by the boot loader
will be
+ appended to the default kernel command string.
+
config CMDLINE_FORCE
bool "Always use the default kernel command string"
- depends on CMDLINE_BOOL
help
Always use the default kernel command string, even if
the boot
loader passes other arguments to the kernel.
This is useful if you cannot or don't want to change
the
command-line options your boot loader passes to the
kernel.
+endchoice
+
config EXTRA_TARGETS
string "Additional default image types"
help
diff --git a/arch/powerpc/kernel/prom_init.c
b/arch/powerpc/kernel/prom_init.c
index 514707ef6779..df29f141dbd2 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -310,6 +310,25 @@ static size_t __init prom_strlcpy(char *dest,
const char *src, size_t size)
return ret;
}
+static size_t __init prom_strlcat(char *dest, const char *src,
size_t count)
+{
+ size_t dsize = prom_strlen(dest);
+ size_t len = prom_strlen(src);
+ size_t res = dsize + len;
+
+ /* This would be a bug */
+ BUG_ON(dsize >= count);
Has you pointed in another mail, BUG_ON() should be avoided here.
I guess if the destination is already full, just return count:
if (dsize >= count)
return count;
Will fix in v3.
quoted
+
+ dest += dsize;
+ count -= dsize;
+ if (len >= count)
+ len = count-1;
+ memcpy(dest, src, len);
+ dest[len] = 0;
+ return res;
+
+}
+
#ifdef CONFIG_PPC_PSERIES
static int __init prom_strtobool(const char *s, bool *res)
{@@ -761,8 +780,13 @@ static void __init early_cmdline_parse(void)
p = prom_cmd_line;
if ((long)prom.chosen > 0)
l = prom_getprop(prom.chosen, "bootargs", p,
COMMAND_LINE_SIZE-1);
The above is pointless in case CONFIG_CMDLINE_FORCE is selected.
Will fix in v3.
quoted
- if (IS_ENABLED(CONFIG_CMDLINE_BOOL) && (l <= 0 || p[0] ==
'\0')) /* dbl check */
+
+ if (IS_ENABLED(CONFIG_CMDLINE_FORCE) || l <= 0 || p[0] ==
'\0')
prom_strlcpy(prom_cmd_line, CONFIG_CMDLINE,
sizeof(prom_cmd_line));
If we can ensure that prom_cmd_line remains empty when
CONFIG_CMDLINE_FORCE is selected (see above comment), then
prom_strlcat() can be used in lieu of prom_strlcpy()
quoted
+ else if (IS_ENABLED(CONFIG_CMDLINE_EXTEND))
+ prom_strlcat(prom_cmd_line, " " CONFIG_CMDLINE,
+ sizeof(prom_cmd_line));
+
prom_printf("command line: %s\n", prom_cmd_line);
#ifdef CONFIG_PPC64
Christophe
Le 02/08/2019 à 00:32, Chris Packham a écrit :
On Thu, 2019-08-01 at 08:14 +0200, Christophe Leroy wrote:
quoted
Le 01/08/2019 à 04:12, Chris Packham a écrit :
quoted
Bring powerpc in line with other architectures that support
extending or
overriding the bootloader provided command line.
The current behaviour is most like CMDLINE_FROM_BOOTLOADER where
the
bootloader command line is preferred but the kernel config can
provide a
fallback so CMDLINE_FROM_BOOTLOADER is the default. CMDLINE_EXTEND
can
be used to append the CMDLINE from the kernel config to the one
provided
by the bootloader.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
---
While I'm at it does anyone think it's worth getting rid of the
default CMDLINE
value if CMDLINE_BOOL and maybe CMDLINE_BOOL? Every defconfig in
the kernel
that sets CMDLINE_BOOL=y also sets CMDLINE to something other than
"console=ttyS0,9600 console=tty0 root=/dev/sda2". Removing
CMDLINE_BOOL and
unconditionally setting the default value of CMDLINE to "" would
clean up the
Kconfig even more.
Note
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/co
mmit/?id=cbe46bd4f5104552b612505b73d366f66efc2341
which is already a step forward.
I guess that default is for users selecting this option manually to
get
a first sensitive CMDLINE. But is it really worth it ?
I'm not even sure if it is working as intended right now. Even without
my changes if I use menuconfig and select CMDLINE_BOOL I end up with
CONFIG_CMDLINE="" in the resulting .config.
I guess if the CONFIG_CMDLINE doesn't exist yet, it will get the default
value. But if it is already there allthough empty, it will remain empty.
So yes I guess you could just drop it for this reason and the other
reasons you said.
Christophe