| Message ID | 34d20d1dbb88f26d418b33985557b0475374a1a5.1617556785.git.christophe.leroy@csgroup.eu |
|---|---|
| State | New |
| Headers | show |
| Series | [RFC,v6,1/1] cmdline: Add capability to both append and prepend at the same time | expand |
On Sun, Apr 4, 2021 at 12:20 PM Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > > One user has expressed the need to both append and prepend some > built-in parameters to the command line provided by the bootloader. > > Allthough it is a corner case, it is easy to implement so let's do it. > > When the user chooses to prepend the bootloader provided command line > with the built-in command line, he is offered the possibility to enter > an additionnal built-in command line to be appended after the > bootloader provided command line. > > It is a complementary feature which has no impact on the already > existing ones and/or the existing defconfig. > > Suggested-by: Daniel Walker <danielwa@cisco.com> > Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> > --- > Sending this out as an RFC, applies on top of the series > ("Implement GENERIC_CMDLINE"). I will add it to the series next spin > unless someone is against it. Well, it works, but you are working around the existing kconfig and the result is not great. You'd never design it this way. Rob
diff --git a/include/linux/cmdline.h b/include/linux/cmdline.h index 020028e2bdf0..fb274a4d5519 100644 --- a/include/linux/cmdline.h +++ b/include/linux/cmdline.h @@ -36,6 +36,9 @@ static __always_inline bool __cmdline_build(char *dst, const char *src) len = cmdline_strlcat(dst, src, COMMAND_LINE_SIZE); + if (IS_ENABLED(CONFIG_CMDLINE_PREPEND)) + len = cmdline_strlcat(dst, " " CONFIG_CMDLINE_MORE, COMMAND_LINE_SIZE); + if (IS_ENABLED(CONFIG_CMDLINE_APPEND)) len = cmdline_strlcat(dst, " " CONFIG_CMDLINE, COMMAND_LINE_SIZE); diff --git a/init/Kconfig b/init/Kconfig index fa002e3765ab..cd3087ff4f28 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -128,6 +128,14 @@ config CMDLINE If this string is not empty, additional choices are proposed below to determine how it will be used by the kernel. +config CMDLINE_MORE + string "Additional default kernel command string" if GENERIC_CMDLINE && CMDLINE_PREPEND + default "" + help + Defines an additional default kernel command string. + If this string is not empty, it is appended to the + command-line arguments provided by the bootloader + choice prompt "Kernel command line type" if CMDLINE != "" default CMDLINE_PREPEND if ARCH_WANT_CMDLINE_PREPEND_BY_DEFAULT @@ -154,7 +162,9 @@ config CMDLINE_PREPEND bool "Prepend to the bootloader kernel arguments" help The default kernel command string will be prepended to the - command-line arguments provided by the bootloader. + command-line arguments provided by the bootloader. When this + option is selected, another string can be added which will + be appended. config CMDLINE_FORCE bool "Always use the default kernel command string"
One user has expressed the need to both append and prepend some built-in parameters to the command line provided by the bootloader. Allthough it is a corner case, it is easy to implement so let's do it. When the user chooses to prepend the bootloader provided command line with the built-in command line, he is offered the possibility to enter an additionnal built-in command line to be appended after the bootloader provided command line. It is a complementary feature which has no impact on the already existing ones and/or the existing defconfig. Suggested-by: Daniel Walker <danielwa@cisco.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- Sending this out as an RFC, applies on top of the series ("Implement GENERIC_CMDLINE"). I will add it to the series next spin unless someone is against it. --- include/linux/cmdline.h | 3 +++ init/Kconfig | 12 +++++++++++- 2 files changed, 14 insertions(+), 1 deletion(-)