linux-kernel - Re: [PATCH 3/4] mm: Make GENERIC

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]

Message-ID: <5504fadd-6174-41c4-90a8-d3ae7f76d7f6@arm.com>
Date: Thu, 13 Feb 2025 11:23:08 +0000
From: Steven Price <steven.price@....com>
To: Anshuman Khandual <anshuman.khandual@....com>, linux-mm@...ck.org
Cc: christophe.leroy@...roup.eu, Paul Walmsley <paul.walmsley@...ive.com>,
 Palmer Dabbelt <palmer@...belt.com>,
 Andrew Morton <akpm@...ux-foundation.org>, linux-riscv@...ts.infradead.org,
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/4] mm: Make GENERIC_PTDUMP dependent on MMU

On 13/02/2025 04:09, Anshuman Khandual wrote:
> There is no page table dump without a MMU. Make this dependency at generic
> level and drop the same from riscv platform instead.
> 
> Cc: Paul Walmsley <paul.walmsley@...ive.com>
> Cc: Palmer Dabbelt <palmer@...belt.com>
> Cc: Andrew Morton <akpm@...ux-foundation.org>
> Cc: linux-riscv@...ts.infradead.org
> Cc: linux-kernel@...r.kernel.org
> Cc: linux-mm@...ck.org
> Signed-off-by: Anshuman Khandual <anshuman.khandual@....com>

As Christophe has pointed out - this is broken. The select will override
the dependency you've added in GENERIC_PTDUMP. Generally have "depends
on" for symbols that are "select"ed is broken. I'd suggest just dropping
this patch.

Steve

> ---
>  arch/riscv/Kconfig | 2 +-
>  mm/Kconfig.debug   | 1 +
>  2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 7612c52e9b1e..c4cdba6460b8 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -112,7 +112,7 @@ config RISCV
>  	select GENERIC_IRQ_SHOW_LEVEL
>  	select GENERIC_LIB_DEVMEM_IS_ALLOWED
>  	select GENERIC_PCI_IOMAP
> -	select GENERIC_PTDUMP if MMU
> +	select GENERIC_PTDUMP
>  	select GENERIC_SCHED_CLOCK
>  	select GENERIC_SMP_IDLE_THREAD
>  	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
> diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
> index a51a1149909a..c08406760d29 100644
> --- a/mm/Kconfig.debug
> +++ b/mm/Kconfig.debug
> @@ -214,6 +214,7 @@ config DEBUG_WX
>  	  If in doubt, say "Y".
>  
>  config GENERIC_PTDUMP
> +	depends on MMU
>  	bool
>  
>  config PTDUMP_CORE