linux-kernel - [PATCH 3.19.y-ckt 015/155] MIPS: CPS: Don't include MT code in non-MT kernels.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1447370309-357-16-git-send-email-kamal@canonical.com>
Date:	Thu, 12 Nov 2015 15:16:09 -0800
From:	Kamal Mostafa <kamal@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Paul Burton <paul.burton@...tec.com>,
	Markos Chandras <markos.chandras@...tec.com>,
	James Hogan <james.hogan@...tec.com>,
	linux-mips@...ux-mips.org, Ralf Baechle <ralf@...ux-mips.org>,
	Kamal Mostafa <kamal@...onical.com>
Subject: [PATCH 3.19.y-ckt 015/155] MIPS: CPS: Don't include MT code in non-MT kernels.

3.19.8-ckt10 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Paul Burton <paul.burton@...tec.com>

commit a5b0f6db0e6cf6224e50f6585e9c8f0c2d38a8f8 upstream.

The MT-specific code in mips_cps_boot_vpes can safely be omitted from
kernels which don't support MT, with the default VPE==0 case being used
as it would be after the has_mt (Config3.MT) check failed at runtime.
Discarding the code entirely will save us a few bytes & allow cleaner
handling of MT ASE instructions by later patches.

Signed-off-by: Paul Burton <paul.burton@...tec.com>
Cc: Markos Chandras <markos.chandras@...tec.com>
Cc: James Hogan <james.hogan@...tec.com>
Cc: linux-mips@...ux-mips.org
Cc: linux-kernel@...r.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10866/
Signed-off-by: Ralf Baechle <ralf@...ux-mips.org>
Signed-off-by: Kamal Mostafa <kamal@...onical.com>
---
 arch/mips/kernel/cps-vec.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S
index 24b8c0b6..d729a5e 100644
--- a/arch/mips/kernel/cps-vec.S
+++ b/arch/mips/kernel/cps-vec.S
@@ -311,6 +311,7 @@ LEAF(mips_cps_boot_vpes)
 
 	/* Calculate this VPEs ID. If the core doesn't support MT use 0 */
 	li	t9, 0
+#ifdef CONFIG_MIPS_MT
 	has_mt	t6, 1f
 
 	/* Find the number of VPEs present in the core */
@@ -330,6 +331,7 @@ LEAF(mips_cps_boot_vpes)
 	/* Retrieve the VPE ID from EBase.CPUNum */
 	mfc0	t9, $15, 1
 	and	t9, t9, t1
+#endif
 
 1:	/* Calculate a pointer to this VPEs struct vpe_boot_config */
 	li	t1, VPEBOOTCFG_SIZE
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/