Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753524AbdF0Ubm (ORCPT ); Tue, 27 Jun 2017 16:31:42 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:48118 "EHLO imgpgp01.kl.imgtec.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753127AbdF0Ube (ORCPT ); Tue, 27 Jun 2017 16:31:34 -0400 X-PGP-Universal: processed; by imgpgp01.kl.imgtec.org on Tue, 27 Jun 2017 22:41:33 +0100 Date: Tue, 27 Jun 2017 21:31:31 +0100 From: James Hogan To: Karl Beldan CC: , , Karl Beldan , , Ralf Baechle , Jonas Gorski Subject: Re: [RESEND PATCH] MIPS: head: Reorder instructions missing a delay slot Message-ID: <20170627203131.GH31455@jhogan-linux.le.imgtec.org> References: <20170627192216.29364-1-karl.beldan+oss@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="qM81t570OJUP5TU/" Content-Disposition: inline In-Reply-To: <20170627192216.29364-1-karl.beldan+oss@gmail.com> User-Agent: Mutt/1.7.2 (2016-11-26) X-Originating-IP: [192.168.154.110] X-ESG-ENCRYPT-TAG: 1b7d744b Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2264 Lines: 70 --qM81t570OJUP5TU/ Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jun 27, 2017 at 07:22:16PM +0000, Karl Beldan wrote: > In this sequence the 'move' is assumed in the delay slot of the 'beq', > but head.S is in reorder mode and the former gets pushed one 'nop' > farther by the assembler. >=20 > The corrected behavior made booting with an UHI supplied dtb erratic. >=20 > Fixes: 15f37e158892 ("MIPS: store the appended dtb address in a variable") > Cc: > Cc: Ralf Baechle > Cc: Jonas Gorski > Signed-off-by: Karl Beldan Ouch, nice catch. Reviewed-by: James Hogan Cheers James > --- > arch/mips/kernel/head.S | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S > index cf05220..d1bb506 100644 > --- a/arch/mips/kernel/head.S > +++ b/arch/mips/kernel/head.S > @@ -106,8 +106,8 @@ NESTED(kernel_entry, 16, sp) # kernel entry point > beq t0, t1, dtb_found > #endif > li t1, -2 > - beq a0, t1, dtb_found > move t2, a1 > + beq a0, t1, dtb_found > =20 > li t2, 0 > dtb_found: > --=20 > 2.10.1 >=20 >=20 --qM81t570OJUP5TU/ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEd80NauSabkiESfLYbAtpk944dnoFAllSwJgACgkQbAtpk944 dnp1DQ/+IEdOAz26vchVYYc5yqErxCK4ArA/5eZ+gcCbm0HkUrg1nSU28KKPI6Lu w8UcdNCi5EoeST4aN6/BySKGPubdq20aJLxzKRr6e+m8+/w7i/8zYuHCmpwcNxMe YpiuUsddUfaahwXfpI1Icwo+HQfyLXEUcglMwojVXT8tktnEWZaUWQQ+JeiQxwsR OHFWMHBF7rHrxzIuK9+rI33Eb83UnbBzCuR+NzrAZBMP8htiaN90JCk+dIDDmvsv bEQSZO5E+YKwvwmt5JA/CuSHJPJ7TaCZgROmQ8I/vmjWJa1xk+qPcFHBEredz4Fc 8QqV+zZY2KcMswtf4nZUhHUznfGAKHw63EnfQm0GpnOBuOTo8U9bE8Z7moUKlk7K D781bn0kvvYsBIxHeIe4JsNOrqPjfmS/A0PKgVaeLEByUZNdGTrzznk7sEa0LyXV 3ccTPztZlbvgGn2CSNjW9d/KENOqjtcFu3fTWTzh7udVN+VLd4SbeuNtT/LhM3RS Va3fQJtMxuz2YGTWlqUTIHXn7DH5+ArbgAaEigx6vDjRa0u7Q7ac47Zrs2uKKdhv Hp5oKJDxA2sXRrJpEdnHpn1QkauI6M6rA3V8NfB40JRKtIxPen3zVui+YDrfjwZy VuUGtCX1DuMPVa0zKBjIfqMKOubgjH6UT44g6DBH8yGVL034beU= =TLTq -----END PGP SIGNATURE----- --qM81t570OJUP5TU/--