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Date:   Wed, 2 Feb 2022 11:34:48 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Brijesh Singh <brijesh.singh@amd.com>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
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        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>,
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        Vlastimil Babka <vbabka@suse.cz>,
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Subject: Re: [PATCH v9 15/43] x86/sev: Register GHCB memory when SEV-SNP is
 active
Message-ID: <YfpeSErxB9KHOd7m@zn.tnic>
References: <20220128171804.569796-1-brijesh.singh@amd.com>
 <20220128171804.569796-16-brijesh.singh@amd.com>
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In-Reply-To: <20220128171804.569796-16-brijesh.singh@amd.com>
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On Fri, Jan 28, 2022 at 11:17:36AM -0600, Brijesh Singh wrote:
> diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
> index 24df739c9c05..b86b48b66a44 100644
> --- a/arch/x86/kernel/sev.c
> +++ b/arch/x86/kernel/sev.c
> @@ -41,7 +41,7 @@ static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE);
>   * Needs to be in the .data section because we need it NULL before bss is
>   * cleared
>   */
> -static struct ghcb __initdata *boot_ghcb;
> +static struct ghcb *boot_ghcb __section(".data");
>  
>  /* Bitmap of SEV features supported by the hypervisor */
>  static u64 sev_hv_features __ro_after_init;
> @@ -161,55 +161,6 @@ void noinstr __sev_es_ist_exit(void)
>  	this_cpu_write(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC], *(unsigned long *)ist);
>  }
>  
> -/*
> - * Nothing shall interrupt this code path while holding the per-CPU
> - * GHCB. The backup GHCB is only for NMIs interrupting this path.
> - *
> - * Callers must disable local interrupts around it.
> - */
> -static noinstr struct ghcb *__sev_get_ghcb(struct ghcb_state *state)

That move doesn't look like it's needed anymore, does it?

I mean, it builds even without it.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette