On 2021/05/15 3:22, [email protected] 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 <[email protected]>
>
> J. R. Okajima
>
> ----------------------------------------
> commit 43e103e1a5975c61334811d16e207e6d0ac57b77
> Author: J. R. Okajima <[email protected]>
> 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 <[email protected]>
> Cc: Peter Zijlstra <[email protected]>
> Signed-off-by: J. R. Okajima <[email protected]>
>
> 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.
>