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Date:   Fri, 8 Jul 2022 18:51:16 -0700
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Subject: Re: [PATCH tip v8] x86/setup: Use rng seeds from setup_data
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To:     "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        X86 ML <x86@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        Andy Lutomirski <luto@kernel.org>
References: <20220707000852.523788-1-Jason@zx2c4.com>
 <20220708113907.891319-1-Jason@zx2c4.com>
From:   "H. Peter Anvin" <hpa@zytor.com>
In-Reply-To: <20220708113907.891319-1-Jason@zx2c4.com>
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On 7/8/22 04:39, Jason A. Donenfeld wrote:
> 
> diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
> index ca0796ac4403..2cbfe630230d 100644
> --- a/arch/x86/include/uapi/asm/bootparam.h
> +++ b/arch/x86/include/uapi/asm/bootparam.h
> @@ -12,6 +12,7 @@
>   #define SETUP_JAILHOUSE			6
>   #define SETUP_CC_BLOB			7
>   #define SETUP_IMA			8
> +#define SETUP_RNG_SEED			9
>   
>   #define SETUP_INDIRECT			(1<<31)
>   

Just one miss here: you need to bump SETUP_TYPE_MAX. It is a bit more 
confusing than it needs to be that SETUP_INDIRECT sits in between, and 
honestly I think SETUP_TYPE_MAX shouldn't include the SETUP_INDIRECT 
bit; however, this is uapi and so we can't change that per se.

Perhaps we should do:

#define SETUP_ENUM_MAX	SETUP_RNG_SEED
#define SETUP_INDIRECT	(1<<31)
#define SETUP_TYPE_MAX	(SETUP_ENUM_MAX | SETUP_INDIRECT)

	-hpa