On Fri, Oct 27, 2023 at 10:17:56AM -0700, Stephen Brennan wrote: > The option CONFIG_IKCONFIG allows the gzip compressed kernel > configuration to be included into vmlinux or a module. In these cases, > debuggers can access the config data and use it to adjust their behavior > according to the configuration. However, distributions rarely enable > this, likely because it uses a fair bit of kernel memory which cannot be > swapped out. > > This means that in practice, the kernel configuration is rarely > available to debuggers. > > So, introduce an alternative, CONFIG_DEBUG_INFO_IKCONFIG. This strategy, > which is only available if IKCONFIG is not already built-in, adds a > section ".debug_linux_ikconfig", to the vmlinux ELF. It will be stripped > out of the final images, but will remain in the debuginfo files. So > debuggers which rely on vmlinux debuginfo can have access to the kernel > configuration, without incurring a cost to the kernel at runtime. > > The configuration is enabled whenever DEBUG_INFO=y and IKCONFIG!=y. The > added section is not large compared to debug info sizes. It won't affect > the runtime kernel at all, and this default will ensure that > distributions intending to create useful debuginfo will get this new > addition for kernel debuggers. > > Signed-off-by: Stephen Brennan <stephen.s.brennan@xxxxxxxxxx> Reviewed-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> Although this begs to support something other than old gz in the future. Luis
