Re: [PATCH v6 04/14] x86: Secure Launch Resource Table header file

From: Matthew Garrett
Date: Fri May 12 2023 - 07:04:31 EST


On Thu, May 04, 2023 at 02:50:13PM +0000, Ross Philipson wrote:

> +#define SLR_TABLE_MAGIC 0x4452544d

>From convention I'd expect this to be 0x534c5254, but not really an
issue.

> +/* SLR defined bootloaders */
> +#define SLR_BOOTLOADER_INVALID 0
> +#define SLR_BOOTLOADER_GRUB 1

Oof. Having the kernel know about bootloaders has not worked out super
well for us in the past. If someone writes a new bootloader, are they
unable to Secure Launch any existing kernels? The pragmatic thing for
them to do would be to just pretend they're grub, which kind of defeats
the point of having this definition...

> +} __packed;

Random nit - why are they all packed? Are there circumstances where two
pieces of code with different assumptions about alignment will be
looking at a single instance of a table? It doesn't seem likely we're
going to be doing DRTM in a 32-bit firmware environment while launching
a 64-bit kernel?