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From:   Arvind Sankar <nivedita@alum.mit.edu>
To:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>
Cc:     linux-efi@vger.kernel.org, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH v2 4/7] x86/boot: Clear direction and interrupt flags in startup_64
Date:   Sun,  2 Feb 2020 12:13:50 -0500
Message-Id: <20200202171353.3736319-5-nivedita@alum.mit.edu>
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 <20200202171353.3736319-1-nivedita@alum.mit.edu>
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startup_32 already clears these flags on entry, do it in startup_64 as
well for consistency.

The direction flag in particular is not specified to be cleared in the
boot protocol documentation, and we currently call into C code
(paging_prepare) without explicitly clearing it.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
---
 arch/x86/boot/compressed/head_64.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 27eb2a6786db..69cc6c68741e 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -264,6 +264,9 @@ SYM_CODE_START(startup_64)
 	 * and command line.
 	 */
 
+	cld
+	cli
+
 	/* Setup data segments. */
 	xorl	%eax, %eax
 	movl	%eax, %ds
-- 
2.24.1