linux-kernel - Re: [Patch] memory: tegra: Skip SID override from Guest VM

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: <2df227df-8bd4-44f1-a361-15b43aea0b47@linaro.org>
Date: Tue, 6 Feb 2024 13:00:44 +0100
From: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To: Sumit Gupta <sumitg@...dia.com>, treding@...dia.com,
 jonathanh@...dia.com, maz@...nel.org, mark.rutland@....com,
 linux-kernel@...r.kernel.org, linux-tegra@...r.kernel.org
Cc: amhetre@...dia.com, bbasu@...dia.com
Subject: Re: [Patch] memory: tegra: Skip SID override from Guest VM

On 06/02/2024 12:48, Sumit Gupta wrote:
> MC SID register access is restricted for Guest VM.
> So, skip the SID override programming from the Guest VM.
> 
> Signed-off-by: Sumit Gupta <sumitg@...dia.com>
> ---
>  drivers/memory/tegra/tegra186.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/memory/tegra/tegra186.c b/drivers/memory/tegra/tegra186.c
> index 1b3183951bfe..df441896b69d 100644
> --- a/drivers/memory/tegra/tegra186.c
> +++ b/drivers/memory/tegra/tegra186.c
> @@ -10,6 +10,7 @@
>  #include <linux/of.h>
>  #include <linux/of_platform.h>
>  #include <linux/platform_device.h>
> +#include <asm/virt.h>

Are you sure this still compile tests?

>  
>  #include <soc/tegra/mc.h>
>  
> @@ -118,6 +119,11 @@ static int tegra186_mc_probe_device(struct tegra_mc *mc, struct device *dev)
>  	unsigned int i, index = 0;
>  	u32 sid;
>  
> +	if (!is_kernel_in_hyp_mode()) {
> +		dev_dbg(mc->dev, "Register access not allowed\n");

Doesn't this depend on hypervisor?

> +		return 0;
> +	}
> +
>  	if (!tegra_dev_iommu_get_stream_id(dev, &sid))
>  		return 0;

Best regards,
Krzysztof