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Date:   Fri, 18 Nov 2022 17:44:20 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Michael Roth <michael.roth@amd.com>
Subject: Re: [PATCH v2 11/16] x86/compressed: move startup32_load_idt() into
 .text section
Message-ID: <Y3e2ZMh5TlfuqreF@zn.tnic>
References: <20220921145422.437618-1-ardb@kernel.org>
 <20220921145422.437618-12-ardb@kernel.org>
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On Wed, Sep 21, 2022 at 04:54:17PM +0200, Ard Biesheuvel wrote:
> Convert startup32_load_idt() into an ordinary function and move it into
> the .text section. This involves turning the rva() immediates into ones
> derived from a local label, and preserving/restoring the %ebp and %ebx
> as per the calling convention.
> 
> Also move the #ifdef to the only existing call site. This makes it clear
> that the function call does nothing if support for memory encryption is
> not compiled in.

I'm not crazy about all that ifdeffery in there but this will need a
serious look.

Btw, you can drop one, diff ontop:

---
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index bc5bd639217e..a862fd8ac0bd 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -726,9 +726,7 @@ SYM_DATA_START(boot32_idt)
 	.quad 0
 	.endr
 SYM_DATA_END_LABEL(boot32_idt, SYM_L_GLOBAL, boot32_idt_end)
-#endif
 
-#ifdef CONFIG_AMD_MEM_ENCRYPT
 	.text
 	.code32
 /*

-- 
Regards/Gruss,
    Boris.

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