Re: [PATCH v1 10/21] powerpc/kexec: refactor for kernel/Kconfig.kexec

2023-06-15 Thread Segher Boessenkool
On Thu, Jun 15, 2023 at 01:34:25PM +1000, Michael Ellerman wrote:
> Eric DeVolder  writes:
> > -config KEXEC_FILE
> > -   bool "kexec file based system call"
> > -   select KEXEC_CORE
> > -   select HAVE_IMA_KEXEC if IMA
> > -   select KEXEC_ELF
> > -   depends on PPC64
> > -   depends on CRYPTO=y
> > -   depends on CRYPTO_SHA256=y
> ...
> > +
> > +config ARCH_HAS_KEXEC_FILE
> > +   def_bool PPC64 && CRYPTO && CRYPTO_SHA256
> 
> The =y's got lost here.
> 
> I think they were both meaningful, because both options are tristate. So
> this previously required them to be built-in (=y), whereas after your
> patch it will allow them to be modules.
> 
> I don't know for sure that those options need to be built-in, but that's
> what the code does now, so this patch shouldn't change it, at least
> without an explanation.

This patch shouldn't change it at all, period.  If you want to change it
(and that sounds like a good idea, if it is possible anyway), that
should be a separate patch.


Segher


Re: [PATCH v1 10/21] powerpc/kexec: refactor for kernel/Kconfig.kexec

2023-06-15 Thread Eric DeVolder




On 6/14/23 22:34, Michael Ellerman wrote:

Eric DeVolder  writes:


The kexec and crash kernel options are provided in the common
kernel/Kconfig.kexec. Utilize the common options and provide
the ARCH_HAS_ and ARCH_SUPPORTS_ entries to recreate the
equivalent set of KEXEC and CRASH options.

Signed-off-by: Eric DeVolder 
Reviewed-by: Sourabh Jain 
---
  arch/powerpc/Kconfig | 55 ++--
  1 file changed, 17 insertions(+), 38 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index bff5820b7cda..36f2fe0cc8a5 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -588,41 +588,21 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
default "y" if PPC_POWERNV
select ARCH_SUPPORTS_MEMORY_FAILURE
  
-config KEXEC

-   bool "kexec system call"
-   depends on PPC_BOOK3S || PPC_E500 || (44x && !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.
-
- It is an ongoing process to be certain the hardware in a machine
- is properly shutdown, so do not be surprised if this code does not
- initially work for you.  As of this writing the exact hardware
- interface is strongly in flux, so no good recommendation can be
- made.
-
-config KEXEC_FILE
-   bool "kexec file based system call"
-   select KEXEC_CORE
-   select HAVE_IMA_KEXEC if IMA
-   select KEXEC_ELF
-   depends on PPC64
-   depends on CRYPTO=y
-   depends on CRYPTO_SHA256=y

...

+
+config ARCH_HAS_KEXEC_FILE
+   def_bool PPC64 && CRYPTO && CRYPTO_SHA256


The =y's got lost here.

I think they were both meaningful, because both options are tristate. So
this previously required them to be built-in (=y), whereas after your
patch it will allow them to be modules.

I don't know for sure that those options need to be built-in, but that's
what the code does now, so this patch shouldn't change it, at least
without an explanation.

cheers

Thanks Michael, I've applied =y's. Good catch!
eric


Re: [PATCH v1 10/21] powerpc/kexec: refactor for kernel/Kconfig.kexec

2023-06-14 Thread Michael Ellerman
Eric DeVolder  writes:

> The kexec and crash kernel options are provided in the common
> kernel/Kconfig.kexec. Utilize the common options and provide
> the ARCH_HAS_ and ARCH_SUPPORTS_ entries to recreate the
> equivalent set of KEXEC and CRASH options.
>
> Signed-off-by: Eric DeVolder 
> Reviewed-by: Sourabh Jain 
> ---
>  arch/powerpc/Kconfig | 55 ++--
>  1 file changed, 17 insertions(+), 38 deletions(-)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index bff5820b7cda..36f2fe0cc8a5 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -588,41 +588,21 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
>   default "y" if PPC_POWERNV
>   select ARCH_SUPPORTS_MEMORY_FAILURE
>  
> -config KEXEC
> - bool "kexec system call"
> - depends on PPC_BOOK3S || PPC_E500 || (44x && !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.
> -
> -   It is an ongoing process to be certain the hardware in a machine
> -   is properly shutdown, so do not be surprised if this code does not
> -   initially work for you.  As of this writing the exact hardware
> -   interface is strongly in flux, so no good recommendation can be
> -   made.
> -
> -config KEXEC_FILE
> - bool "kexec file based system call"
> - select KEXEC_CORE
> - select HAVE_IMA_KEXEC if IMA
> - select KEXEC_ELF
> - depends on PPC64
> - depends on CRYPTO=y
> - depends on CRYPTO_SHA256=y
...
> +
> +config ARCH_HAS_KEXEC_FILE
> + def_bool PPC64 && CRYPTO && CRYPTO_SHA256

The =y's got lost here.

I think they were both meaningful, because both options are tristate. So
this previously required them to be built-in (=y), whereas after your
patch it will allow them to be modules.

I don't know for sure that those options need to be built-in, but that's
what the code does now, so this patch shouldn't change it, at least
without an explanation.

cheers


[PATCH v1 10/21] powerpc/kexec: refactor for kernel/Kconfig.kexec

2023-06-12 Thread Eric DeVolder
The kexec and crash kernel options are provided in the common
kernel/Kconfig.kexec. Utilize the common options and provide
the ARCH_HAS_ and ARCH_SUPPORTS_ entries to recreate the
equivalent set of KEXEC and CRASH options.

Signed-off-by: Eric DeVolder 
Reviewed-by: Sourabh Jain 
---
 arch/powerpc/Kconfig | 55 ++--
 1 file changed, 17 insertions(+), 38 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index bff5820b7cda..36f2fe0cc8a5 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -588,41 +588,21 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
default "y" if PPC_POWERNV
select ARCH_SUPPORTS_MEMORY_FAILURE
 
-config KEXEC
-   bool "kexec system call"
-   depends on PPC_BOOK3S || PPC_E500 || (44x && !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.
-
- It is an ongoing process to be certain the hardware in a machine
- is properly shutdown, so do not be surprised if this code does not
- initially work for you.  As of this writing the exact hardware
- interface is strongly in flux, so no good recommendation can be
- made.
-
-config KEXEC_FILE
-   bool "kexec file based system call"
-   select KEXEC_CORE
-   select HAVE_IMA_KEXEC if IMA
-   select KEXEC_ELF
-   depends on PPC64
-   depends on CRYPTO=y
-   depends on CRYPTO_SHA256=y
-   help
- This is a new version of the kexec system call. This call is
- file based and takes in file descriptors as system call arguments
- for kernel and initramfs as opposed to a list of segments as is the
- case for the older kexec call.
+config ARCH_HAS_KEXEC
+   def_bool PPC_BOOK3S || PPC_E500 || (44x && !SMP)
+
+config ARCH_HAS_KEXEC_FILE
+   def_bool PPC64 && CRYPTO && CRYPTO_SHA256
 
 config ARCH_HAS_KEXEC_PURGATORY
def_bool KEXEC_FILE
 
+config ARCH_SUPPORTS_KEXEC_FILE
+   def_bool y
+   depends on KEXEC_FILE
+   select KEXEC_ELF
+   select HAVE_IMA_KEXEC if IMA
+
 config PPC64_BIG_ENDIAN_ELF_ABI_V2
bool "Build big-endian kernel using ELF ABI V2 (EXPERIMENTAL)"
depends on PPC64 && CPU_BIG_ENDIAN
@@ -682,14 +662,13 @@ config RELOCATABLE_TEST
  loaded at, which tends to be non-zero and therefore test the
  relocation code.
 
-config CRASH_DUMP
-   bool "Build a dump capture kernel"
-   depends on PPC64 || PPC_BOOK3S_32 || PPC_85xx || (44x && !SMP)
+config ARCH_HAS_CRASH_DUMP
+   def_bool PPC64 || PPC_BOOK3S_32 || PPC_85xx || (44x && !SMP)
+
+config ARCH_SUPPORTS_CRASH_DUMP
+   def_bool y
+   depends on CRASH_DUMP
select RELOCATABLE if PPC64 || 44x || PPC_85xx
-   help
- Build a kernel suitable for use as a dump capture kernel.
- The same kernel binary can be used as production kernel and dump
- capture kernel.
 
 config FA_DUMP
bool "Firmware-assisted dump"
-- 
2.31.1