linux-kernel - [PATCH] ARCv2: Don't pretend we may set L-bit in STATUS32 with kflag instruction

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Date:   Thu, 18 Jan 2018 21:07:21 +0300
From:   Alexey Brodkin <Alexey.Brodkin@...opsys.com>
To:     linux-snps-arc@...ts.infradead.org
Cc:     linux-kernel@...r.kernel.org,
        Vineet Gupta <Vineet.Gupta1@...opsys.com>,
        Alexey Brodkin <Alexey.Brodkin@...opsys.com>
Subject: [PATCH] ARCv2: Don't pretend we may set L-bit in STATUS32 with kflag instruction

As per PRM "kflag" instruction doesn't change state of
L-flag ("Zero-Overhead loop disabled") in STATUS32 register
so let's not act as if we can affect this bit.

Signed-off-by: Alexey Brodkin <abrodkin@...opsys.com>
---
 arch/arc/include/asm/entry-arcv2.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arc/include/asm/entry-arcv2.h b/arch/arc/include/asm/entry-arcv2.h
index 257a68f3c2fe..309f4e6721b3 100644
--- a/arch/arc/include/asm/entry-arcv2.h
+++ b/arch/arc/include/asm/entry-arcv2.h
@@ -184,7 +184,7 @@
 .macro FAKE_RET_FROM_EXCPN
 	lr      r9, [status32]
 	bic     r9, r9, (STATUS_U_MASK|STATUS_DE_MASK|STATUS_AE_MASK)
-	or      r9, r9, (STATUS_L_MASK|STATUS_IE_MASK)
+	or      r9, r9, STATUS_IE_MASK
 	kflag   r9
 .endm
 
-- 
2.11.0