On Tue, Mar 02, 2021 at 05:25:22PM +0000, Christophe Leroy wrote: > Most architectures have similar boot command line manipulation > options. This patchs adds the definition in init/Kconfig, gated by > CONFIG_HAVE_CMDLINE that the architectures can select to use them. > > In order to use this, a few architectures will have to change their > CONFIG options: > - riscv has to replace CMDLINE_FALLBACK by CMDLINE_FROM_BOOTLOADER > - architectures using CONFIG_CMDLINE_OVERRIDE or > CONFIG_CMDLINE_OVERWRITE have to replace them by CONFIG_CMDLINE_FORCE. > > Architectures also have to define CONFIG_DEFAULT_CMDLINE. > > Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > --- > init/Kconfig | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 56 insertions(+) > > diff --git a/init/Kconfig b/init/Kconfig > index 22946fe5ded9..a0f2ad9467df 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -117,6 +117,62 @@ config INIT_ENV_ARG_LIMIT > Maximum of each of the number of arguments and environment > variables passed to init from the kernel command line. > > +config HAVE_CMDLINE > + bool > + > +config CMDLINE_BOOL > + bool "Default bootloader kernel arguments" > + depends on HAVE_CMDLINE > + help > + On some platforms, there is currently no way for the boot loader to > + pass arguments to the kernel. For these platforms, you can supply > + some command-line options at build time by entering them here. In > + most cases you will need to specify the root device here. Why is this needed as well as CMDLINE_FROM_BOOTLOADER? IIUC, the latter will use CONFIG_CMDLINE if it fails to get anything from the bootloader, which sounds like the same scenario. > +config CMDLINE > + string "Initial kernel command string" s/Initial/Default which is then consistent with the rest of the text here. > + depends on CMDLINE_BOOL Ah, so this is a bit different and I don't think lines-up with the CMDLINE_BOOL help text. > + default DEFAULT_CMDLINE > + help > + On some platforms, there is currently no way for the boot loader to > + pass arguments to the kernel. For these platforms, you can supply > + some command-line options at build time by entering them here. In > + most cases you will need to specify the root device here. (same stale text) > +choice > + prompt "Kernel command line type" if CMDLINE != "" > + default CMDLINE_FROM_BOOTLOADER > + help > + Selects the way you want to use the default kernel arguments. How about: "Determines how the default kernel arguments are combined with any arguments passed by the 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 Can we rename this to CMDLINE_APPEND, please? There is code in the tree which disagrees about what CMDLINE_EXTEND means, so that will need be to be updated to be consistent (e.g. the EFI stub parsing order). Having the generic option with a different name means we won't accidentally end up with the same inconsistent behaviours. > + bool "Extend bootloader kernel arguments" "Append to the bootloader kernel arguments" > + help > + The default kernel command string will be appended to the > + command-line arguments provided during boot. s/provided during boot/provided by the bootloader/ > + > +config CMDLINE_PREPEND > + bool "Prepend bootloader kernel arguments" "Prepend to the bootloader kernel arguments" > + help > + The default kernel command string will be prepend to the > + command-line arguments provided during boot. s/prepend/prepended/ s/provided during boot/provided by the bootloader/ > + > +config CMDLINE_FORCE > + bool "Always use the default kernel command string" > + 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. I find the "This is useful if ..." sentence really confusing, perhaps just remove it? I'd then tweak it to be: "Always use the default kernel command string, ignoring any arguments provided by the bootloader." Will
