Patchwork [66/93] powerpc/book3e: Disable interrupt after preempt_schedule_irq

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Submitter Herton Ronaldo Krzesinski
Date Feb. 5, 2013, 10:06 p.m.
Message ID <1360102042-10732-67-git-send-email-herton.krzesinski@canonical.com>
Download mbox | patch
Permalink /patch/218428/
State New
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Comments

Herton Ronaldo Krzesinski - Feb. 5, 2013, 10:06 p.m.
3.5.7.5 -stable review patch.  If anyone has any objections, please let me know.

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

From: Tiejun Chen <tiejun.chen@windriver.com>

commit 572177d7c77db1981ba2563e01478126482c43bc upstream.

In preempt case current arch_local_irq_restore() from
preempt_schedule_irq() may enable hard interrupt but we really
should disable interrupts when we return from the interrupt,
and so that we don't get interrupted after loading SRR0/1.

Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
---
 arch/powerpc/kernel/entry_64.S |   13 +++++++++++++
 1 file changed, 13 insertions(+)

Patch

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 8d2fa24..fad2e83 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -616,6 +616,19 @@  resume_kernel:
 	ld	r4,TI_FLAGS(r9)
 	andi.	r0,r4,_TIF_NEED_RESCHED
 	bne	1b
+
+	/*
+	 * arch_local_irq_restore() from preempt_schedule_irq above may
+	 * enable hard interrupt but we really should disable interrupts
+	 * when we return from the interrupt, and so that we don't get
+	 * interrupted after loading SRR0/1.
+	 */
+#ifdef CONFIG_PPC_BOOK3E
+	wrteei	0
+#else
+	ld	r10,PACAKMSR(r13) /* Get kernel MSR without EE */
+	mtmsrd	r10,1		  /* Update machine state */
+#endif /* CONFIG_PPC_BOOK3E */
 #endif /* CONFIG_PREEMPT */
 
 	.globl	fast_exc_return_irq