From: Paul Mundt <lethal@linux-sh.org>
Date: Mon, 18 Jan 2010 11:39:49 +0000 (+0900)
Subject: sh: Need IRQs enabled for init_fpu().
X-Git-Tag: firefly_0821_release~9833^2~3107^2~117
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4291b730cd0f0cf98a90d946b6cabbd804397350;p=firefly-linux-kernel-4.4.55.git

sh: Need IRQs enabled for init_fpu().

This tosses in a local_irq_enable()/disable() pair around the init_fpu()
callsite in the FPU state restore exception handler. Fixes up a slab BUG
triggered by making a slab cache allocation that can sleep whilst
irqs_disabled(). This follows the behaviour undertaken by the x86
implementation.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
---

diff --git a/arch/sh/kernel/cpu/fpu.c b/arch/sh/kernel/cpu/fpu.c
index c23e6727002a..f059ed62cf57 100644
--- a/arch/sh/kernel/cpu/fpu.c
+++ b/arch/sh/kernel/cpu/fpu.c
@@ -56,6 +56,7 @@ void fpu_state_restore(struct pt_regs *regs)
 	}
 
 	if (!tsk_used_math(tsk)) {
+		local_irq_enable();
 		/*
 		 * does a slab alloc which can sleep
 		 */
@@ -66,6 +67,7 @@ void fpu_state_restore(struct pt_regs *regs)
 			do_group_exit(SIGKILL);
 			return;
 		}
+		local_irq_disable();
 	}
 
 	grab_fpu(regs);