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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Wed, 28 Jun 2023 09:20:36 +0100
From:   Conor Dooley <conor.dooley@...rochip.com>
To:     Eric DeVolder <eric.devolder@...cle.com>
CC:     <linux@...linux.org.uk>, <catalin.marinas@....com>,
        <will@...nel.org>, <chenhuacai@...nel.org>, <geert@...ux-m68k.org>,
        <tsbogend@...ha.franken.de>,
        <James.Bottomley@...senpartnership.com>, <deller@....de>,
        <ysato@...rs.sourceforge.jp>, <dalias@...c.org>,
        <glaubitz@...sik.fu-berlin.de>, <tglx@...utronix.de>,
        <mingo@...hat.com>, <bp@...en8.de>, <dave.hansen@...ux.intel.com>,
        <x86@...nel.org>, <linux-kernel@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-ia64@...r.kernel.org>, <loongarch@...ts.linux.dev>,
        <linux-m68k@...ts.linux-m68k.org>, <linux-mips@...r.kernel.org>,
        <linux-parisc@...r.kernel.org>, <linuxppc-dev@...ts.ozlabs.org>,
        <linux-riscv@...ts.infradead.org>, <linux-s390@...r.kernel.org>,
        <linux-sh@...r.kernel.org>, <kernel@...0n.name>,
        <mpe@...erman.id.au>, <npiggin@...il.com>,
        <christophe.leroy@...roup.eu>, <paul.walmsley@...ive.com>,
        <palmer@...belt.com>, <aou@...s.berkeley.edu>, <hca@...ux.ibm.com>,
        <gor@...ux.ibm.com>, <agordeev@...ux.ibm.com>,
        <borntraeger@...ux.ibm.com>, <svens@...ux.ibm.com>,
        <hpa@...or.com>, <keescook@...omium.org>, <paulmck@...nel.org>,
        <peterz@...radead.org>, <frederic@...nel.org>,
        <akpm@...ux-foundation.org>, <ardb@...nel.org>,
        <samitolvanen@...gle.com>, <juerg.haefliger@...onical.com>,
        <arnd@...db.de>, <rmk+kernel@...linux.org.uk>,
        <linus.walleij@...aro.org>, <sebastian.reichel@...labora.com>,
        <rppt@...nel.org>, <kirill.shutemov@...ux.intel.com>,
        <anshuman.khandual@....com>, <ziy@...dia.com>,
        <masahiroy@...nel.org>, <ndesaulniers@...gle.com>,
        <mhiramat@...nel.org>, <ojeda@...nel.org>,
        <thunder.leizhen@...wei.com>, <xin3.li@...el.com>, <tj@...nel.org>,
        <gregkh@...uxfoundation.org>, <tsi@...oix.net>, <bhe@...hat.com>,
        <hbathini@...ux.ibm.com>, <sourabhjain@...ux.ibm.com>,
        <boris.ostrovsky@...cle.com>, <konrad.wilk@...cle.com>
Subject: Re: [PATCH v3 11/13] riscv/kexec: refactor for kernel/Kconfig.kexec

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@...cle.com>
> ---
>  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?

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
>

Download attachment "signature.asc" of type "application/pgp-signature" (229 bytes)