From 8c7009efba8e31d22da3b06ac9b8234fda7549eb Mon Sep 17 00:00:00 2001
From: Anton Blanchard <anton@samba.org>
Date: Mon, 3 Sep 2012 16:51:10 +0000
Subject: [PATCH] --- yaml --- r: 322495 b: refs/heads/master c:
 714332858bfd40dcf8f741498336d93875c23aa7 h: refs/heads/master i:   322493:
 8915a944d2eb465c6b2db7b4c76bdfcbe7428d70   322491:
 14e25dcc00b1da37b00e2885da263f4f48b078bd   322487:
 dca0f4c6c4f956b6f6af669b946b4162ff737121   322479:
 abcbe9bb874a153abd22bd41c3d3da90be13c2b6   322463:
 f202676711ad7a82f7408dad02ab9511c26ed96e   322431:
 737755d7a0d2ef98be08f4888afb4960013ea2a0 v: v3

---
 [refs]                                  |  2 +-
 trunk/arch/powerpc/kernel/asm-offsets.c |  1 +
 trunk/arch/powerpc/kernel/entry_64.S    | 23 +++++++++++++++++------
 3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index c02e546466a1..fa94c3e7f0ca 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1021cb268b3025573c4811f1dee4a11260c4507b
+refs/heads/master: 714332858bfd40dcf8f741498336d93875c23aa7
diff --git a/trunk/arch/powerpc/kernel/asm-offsets.c b/trunk/arch/powerpc/kernel/asm-offsets.c
index 85b05c463fae..e8995727b1c1 100644
--- a/trunk/arch/powerpc/kernel/asm-offsets.c
+++ b/trunk/arch/powerpc/kernel/asm-offsets.c
@@ -76,6 +76,7 @@ int main(void)
 	DEFINE(SIGSEGV, SIGSEGV);
 	DEFINE(NMI_MASK, NMI_MASK);
 	DEFINE(THREAD_DSCR, offsetof(struct thread_struct, dscr));
+	DEFINE(THREAD_DSCR_INHERIT, offsetof(struct thread_struct, dscr_inherit));
 #else
 	DEFINE(THREAD_INFO, offsetof(struct task_struct, stack));
 #endif /* CONFIG_PPC64 */
diff --git a/trunk/arch/powerpc/kernel/entry_64.S b/trunk/arch/powerpc/kernel/entry_64.S
index 4b01a25e29ef..b40e0b4815b3 100644
--- a/trunk/arch/powerpc/kernel/entry_64.S
+++ b/trunk/arch/powerpc/kernel/entry_64.S
@@ -370,6 +370,12 @@ _GLOBAL(ret_from_fork)
 	li	r3,0
 	b	syscall_exit
 
+	.section	".toc","aw"
+DSCR_DEFAULT:
+	.tc dscr_default[TC],dscr_default
+
+	.section	".text"
+
 /*
  * This routine switches between two different tasks.  The process
  * state of one is saved on its kernel stack.  Then the state
@@ -509,9 +515,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
 	mr	r1,r8		/* start using new stack pointer */
 	std	r7,PACAKSAVE(r13)
 
-	ld	r6,_CCR(r1)
-	mtcrf	0xFF,r6
-
 #ifdef CONFIG_ALTIVEC
 BEGIN_FTR_SECTION
 	ld	r0,THREAD_VRSAVE(r4)
@@ -520,14 +523,22 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 #endif /* CONFIG_ALTIVEC */
 #ifdef CONFIG_PPC64
 BEGIN_FTR_SECTION
+	lwz	r6,THREAD_DSCR_INHERIT(r4)
+	ld	r7,DSCR_DEFAULT@toc(2)
 	ld	r0,THREAD_DSCR(r4)
-	cmpd	r0,r25
-	beq	1f
+	cmpwi	r6,0
+	bne	1f
+	ld	r0,0(r7)
+1:	cmpd	r0,r25
+	beq	2f
 	mtspr	SPRN_DSCR,r0
-1:	
+2:
 END_FTR_SECTION_IFSET(CPU_FTR_DSCR)
 #endif
 
+	ld	r6,_CCR(r1)
+	mtcrf	0xFF,r6
+
 	/* r3-r13 are destroyed -- Cort */
 	REST_8GPRS(14, r1)
 	REST_10GPRS(22, r1)