linux-kernel - RE: [PATCH] dma: Per-NUMA-node CMA should depend on NUMA

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:   Mon, 26 Oct 2020 20:07:43 +0000
From:   "Song Bao Hua (Barry Song)" <song.bao.hua@...ilicon.com>
To:     Robin Murphy <robin.murphy@....com>, "hch@....de" <hch@....de>
CC:     "iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] dma: Per-NUMA-node CMA should depend on NUMA



> -----Original Message-----
> From: Robin Murphy [mailto:robin.murphy@....com]
> Sent: Tuesday, October 27, 2020 1:25 AM
> To: hch@....de
> Cc: iommu@...ts.linux-foundation.org; linux-kernel@...r.kernel.org; Song Bao
> Hua (Barry Song) <song.bao.hua@...ilicon.com>
> Subject: [PATCH] dma: Per-NUMA-node CMA should depend on NUMA
> 
> Offering DMA_PERNUMA_CMA to non-NUMA configs is pointless.
> 

This is right.

> Signed-off-by: Robin Murphy <robin.murphy@....com>
> ---
>  kernel/dma/Kconfig | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
> index c99de4a21458..964b74c9b7e3 100644
> --- a/kernel/dma/Kconfig
> +++ b/kernel/dma/Kconfig
> @@ -125,7 +125,8 @@ if  DMA_CMA
> 
>  config DMA_PERNUMA_CMA
>  	bool "Enable separate DMA Contiguous Memory Area for each NUMA
> Node"
> -	default NUMA && ARM64
> +	depends on NUMA
> +	default ARM64

On the other hand, at this moment, only ARM64 is calling the init code
to get per_numa cma. Do we need to
depends on NUMA && ARM64 ?
so that this is not enabled by non-arm64?

>  	help
>  	  Enable this option to get pernuma CMA areas so that devices like
>  	  ARM64 SMMU can get local memory by DMA coherent APIs.
> --
 
Thanks
Barry