linux-kernel - Re: PATCH: Re: LOCKDEP customizable numbers upper limit

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: <11faf952-c0f8-6e1d-3560-12d77847a8ac@i-love.sakura.ne.jp>
Date:   Sat, 15 May 2021 07:41:02 +0900
From:   Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>
To:     hooanon05g@...il.com
Cc:     linux-kernel@...r.kernel.org, peterz@...radead.org
Subject: Re: PATCH: Re: LOCKDEP customizable numbers upper limit

On 2021/05/15 3:22, hooanon05g@...il.com wrote:
> Tetsuo Handa:
>> Please submit a patch that avoids only BUILD_BUG_ON().
> 
> Here it is.

Thank you. In practice, nobody will increase by more than 5 bits.

Acked-by: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>

> 
> J. R. Okajima
> 
> ----------------------------------------
> commit 43e103e1a5975c61334811d16e207e6d0ac57b77
> Author: J. R. Okajima <hooanon05g@...il.com>
> Date:   Sat May 15 03:17:10 2021 +0900
> 
>     LOCKDEP: upper limit LOCKDEP_CHAINS_BITS
>     
>     CONFIG_LOCKDEP_CHAINS_BITS value decides the size of chain_hlocks[] in
>     kernel/locking/lockdep.c, and it is checked by add_chain_cache() with
>             BUILD_BUG_ON((1UL << 24) <= ARRAY_SIZE(chain_hlocks));
>     This patch is just to silence BUILD_BUG_ON().
>     
>     See-also: https://marc.info/?l=linux-kernel&m=162091320503900&w=2
>     Cc: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
>     Cc: Peter Zijlstra <peterz@...radead.org>
>     Signed-off-by: J. R. Okajima <hooanon05g@...il.com>
> 
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 678c13967580e..999ed5aa6bcee 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -1390,7 +1390,7 @@ config LOCKDEP_BITS
>  config LOCKDEP_CHAINS_BITS
>  	int "Bitsize for MAX_LOCKDEP_CHAINS"
>  	depends on LOCKDEP && !LOCKDEP_SMALL
> -	range 10 30
> +	range 10 21
>  	default 16
>  	help
>  	  Try increasing this value if you hit "BUG: MAX_LOCKDEP_CHAINS too low!" message.
>