Re: [PATCH v3 11/13] riscv/kexec: refactor for kernel/Kconfig.kexec

[Eric DeVolder <eric.devolder@xxxxxxxxxx>]

On 6/28/23 03:20, Conor Dooley wrote:
> Hey Eric,
>
> On Mon, Jun 26, 2023 at 12:13:30PM -0400, Eric DeVolder wrote:
> > The kexec and crash kernel options are provided in the common
> > kernel/Kconfig.kexec. Utilize the common options and provide
> > the ARCH_SUPPORTS_ and ARCH_SELECTS_ entries to recreate the
>
> > equivalent set of KEXEC and CRASH options.
>
> I find this diff a little hard to follow (since the other half off the
> change is in another patch), so it may be me missing something, but are
> you sure?
>
> > Signed-off-by: Eric DeVolder <eric.devolder@xxxxxxxxxx>
> > ---
> >   arch/riscv/Kconfig | 48 ++++++++++++++--------------------------------
> >   1 file changed, 14 insertions(+), 34 deletions(-)
> >
> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > index 5966ad97c30c..c484abd9bbfd 100644
> > --- a/arch/riscv/Kconfig
> > +++ b/arch/riscv/Kconfig
> > @@ -585,48 +585,28 @@ config RISCV_BOOT_SPINWAIT
> >   
> >   	  If unsure what to do here, say N.
> >   
> > -config KEXEC
> > -	bool "Kexec system call"
> > -	depends on MMU
> > +config ARCH_SUPPORTS_KEXEC
> > +	def_bool MMU
> > +
> > +config ARCH_SELECTS_KEXEC
> > +	def_bool y
> > +	depends on KEXEC
> >   	select HOTPLUG_CPU if SMP
> > -	select KEXEC_CORE
> > -	help
> > -	  kexec is a system call that implements the ability to shutdown your
> > -	  current kernel, and to start another kernel. It is like a reboot
> > -	  but it is independent of the system firmware. And like a reboot
> > -	  you can start any kernel with it, not just Linux.
> >   
> > -	  The name comes from the similarity to the exec system call.
> > +config ARCH_SUPPORTS_KEXEC_FILE
> > +	def_bool 64BIT && MMU && CRYPTO=y && CRYPTO_SHA256=y
>
> This looks like a change to me. Previously, only KEXEC_PURGATORY
> required these crypto options to be like so, but now KEXEC_FILE needs
> them too.
>
> What am I missing?
Conor,
Thanks for looking at this! Indeed I erroneously applied the CRYPTO=y && CRYPTO_SHA256=y
to KEXEC_FILE rather than PURGATORY. I will correct for v4!
Thanks!
eric

> Cheers,
> Conor.
>
> >   
> > -config KEXEC_FILE
> > -	bool "kexec file based systmem call"
> > -	depends on 64BIT && MMU
> > -	select HAVE_IMA_KEXEC if IMA
> > -	select KEXEC_CORE
> > +config ARCH_SELECTS_KEXEC_FILE
> > +	def_bool y
> > +	depends on KEXEC_FILE
> >   	select KEXEC_ELF
> > -	help
> > -	  This is new version of kexec system call. This system call is
> > -	  file based and takes file descriptors as system call argument
> > -	  for kernel and initramfs as opposed to list of segments as
> > -	  accepted by previous system call.
> > -
> > -	  If you don't know what to do here, say Y.
> > +	select HAVE_IMA_KEXEC if IMA
> >   
> >   config ARCH_HAS_KEXEC_PURGATORY
> >   	def_bool KEXEC_FILE
> > -	depends on CRYPTO=y
> > -	depends on CRYPTO_SHA256=y
> >   
> > -config CRASH_DUMP
> > -	bool "Build kdump crash kernel"
> > -	help
> > -	  Generate crash dump after being started by kexec. This should
> > -	  be normally only set in special crash dump kernels which are
> > -	  loaded in the main kernel with kexec-tools into a specially
> > -	  reserved region and then later executed after a crash by
> > -	  kdump/kexec.
> > -
> > -	  For more details see Documentation/admin-guide/kdump/kdump.rst
> > +config ARCH_SUPPORTS_CRASH_DUMP
> > +	def_bool y
> >   
> >   config COMPAT
> >   	bool "Kernel support for 32-bit U-mode"
> > --
> > 2.31.1