[PATCH 3.12 116/127] sparc64: Fix illegal relative branches in hypervisor patched TLB cross-call code.

[Jiri Slaby]

From: "David S. Miller" <davem@xxxxxxxxxxxxx>

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

===============

[ Upstream commit a236441bb69723032db94128761a469030c3fe6d ]

Just like the non-cross-call TLB flush handlers, the cross-call ones need
to avoid doing PC-relative branches outside of their code blocks.

Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 arch/sparc/mm/ultra.S | 42 ++++++++++++++++++++++++++++++------------
 1 file changed, 30 insertions(+), 12 deletions(-)

diff --git a/arch/sparc/mm/ultra.S b/arch/sparc/mm/ultra.S
index 5128d38b1d1a..0fa2e6202c1f 100644
--- a/arch/sparc/mm/ultra.S
+++ b/arch/sparc/mm/ultra.S
@@ -484,7 +484,7 @@ cheetah_patch_cachetlbops:
 	 */
 	.align		32
 	.globl		xcall_flush_tlb_mm
-xcall_flush_tlb_mm:	/* 21 insns */
+xcall_flush_tlb_mm:	/* 24 insns */
 	mov		PRIMARY_CONTEXT, %g2
 	ldxa		[%g2] ASI_DMMU, %g3
 	srlx		%g3, CTX_PGSZ1_NUC_SHIFT, %g4
@@ -506,9 +506,12 @@ xcall_flush_tlb_mm:	/* 21 insns */
 	nop
 	nop
 	nop
+	nop
+	nop
+	nop
 
 	.globl		xcall_flush_tlb_page
-xcall_flush_tlb_page:	/* 17 insns */
+xcall_flush_tlb_page:	/* 20 insns */
 	/* %g5=context, %g1=vaddr */
 	mov		PRIMARY_CONTEXT, %g4
 	ldxa		[%g4] ASI_DMMU, %g2
@@ -527,9 +530,12 @@ xcall_flush_tlb_page:	/* 17 insns */
 	retry
 	nop
 	nop
+	nop
+	nop
+	nop
 
 	.globl		xcall_flush_tlb_kernel_range
-xcall_flush_tlb_kernel_range:	/* 25 insns */
+xcall_flush_tlb_kernel_range:	/* 28 insns */
 	sethi		%hi(PAGE_SIZE - 1), %g2
 	or		%g2, %lo(PAGE_SIZE - 1), %g2
 	andn		%g1, %g2, %g1
@@ -555,6 +561,9 @@ xcall_flush_tlb_kernel_range:	/* 25 insns */
 	nop
 	nop
 	nop
+	nop
+	nop
+	nop
 
 	/* This runs in a very controlled environment, so we do
 	 * not need to worry about BH races etc.
@@ -737,7 +746,7 @@ __hypervisor_tlb_xcall_error:
 	ba,a,pt	%xcc, rtrap
 
 	.globl		__hypervisor_xcall_flush_tlb_mm
-__hypervisor_xcall_flush_tlb_mm: /* 21 insns */
+__hypervisor_xcall_flush_tlb_mm: /* 24 insns */
 	/* %g5=ctx, g1,g2,g3,g4,g7=scratch, %g6=unusable */
 	mov		%o0, %g2
 	mov		%o1, %g3
@@ -751,7 +760,7 @@ __hypervisor_xcall_flush_tlb_mm: /* 21 insns */
 	mov		HV_FAST_MMU_DEMAP_CTX, %o5
 	ta		HV_FAST_TRAP
 	mov		HV_FAST_MMU_DEMAP_CTX, %g6
-	brnz,pn		%o0, __hypervisor_tlb_xcall_error
+	brnz,pn		%o0, 1f
 	 mov		%o0, %g5
 	mov		%g2, %o0
 	mov		%g3, %o1
@@ -760,9 +769,12 @@ __hypervisor_xcall_flush_tlb_mm: /* 21 insns */
 	mov		%g7, %o5
 	membar		#Sync
 	retry
+1:	sethi		%hi(__hypervisor_tlb_xcall_error), %g4
+	jmpl		%g4 + %lo(__hypervisor_tlb_xcall_error), %g0
+	 nop
 
 	.globl		__hypervisor_xcall_flush_tlb_page
-__hypervisor_xcall_flush_tlb_page: /* 17 insns */
+__hypervisor_xcall_flush_tlb_page: /* 20 insns */
 	/* %g5=ctx, %g1=vaddr */
 	mov		%o0, %g2
 	mov		%o1, %g3
@@ -774,16 +786,19 @@ __hypervisor_xcall_flush_tlb_page: /* 17 insns */
 	sllx		%o0, PAGE_SHIFT, %o0
 	ta		HV_MMU_UNMAP_ADDR_TRAP
 	mov		HV_MMU_UNMAP_ADDR_TRAP, %g6
-	brnz,a,pn	%o0, __hypervisor_tlb_xcall_error
+	brnz,a,pn	%o0, 1f
 	 mov		%o0, %g5
 	mov		%g2, %o0
 	mov		%g3, %o1
 	mov		%g4, %o2
 	membar		#Sync
 	retry
+1:	sethi		%hi(__hypervisor_tlb_xcall_error), %g4
+	jmpl		%g4 + %lo(__hypervisor_tlb_xcall_error), %g0
+	 nop
 
 	.globl		__hypervisor_xcall_flush_tlb_kernel_range
-__hypervisor_xcall_flush_tlb_kernel_range: /* 25 insns */
+__hypervisor_xcall_flush_tlb_kernel_range: /* 28 insns */
 	/* %g1=start, %g7=end, g2,g3,g4,g5,g6=scratch */
 	sethi		%hi(PAGE_SIZE - 1), %g2
 	or		%g2, %lo(PAGE_SIZE - 1), %g2
@@ -800,7 +815,7 @@ __hypervisor_xcall_flush_tlb_kernel_range: /* 25 insns */
 	mov		HV_MMU_ALL, %o2	/* ARG2: flags */
 	ta		HV_MMU_UNMAP_ADDR_TRAP
 	mov		HV_MMU_UNMAP_ADDR_TRAP, %g6
-	brnz,pn		%o0, __hypervisor_tlb_xcall_error
+	brnz,pn		%o0, 1f
 	 mov		%o0, %g5
 	sethi		%hi(PAGE_SIZE), %o2
 	brnz,pt		%g3, 1b
@@ -810,6 +825,9 @@ __hypervisor_xcall_flush_tlb_kernel_range: /* 25 insns */
 	mov		%g7, %o2
 	membar		#Sync
 	retry
+1:	sethi		%hi(__hypervisor_tlb_xcall_error), %g4
+	jmpl		%g4 + %lo(__hypervisor_tlb_xcall_error), %g0
+	 nop
 
 	/* These just get rescheduled to PIL vectors. */
 	.globl		xcall_call_function
@@ -894,21 +912,21 @@ hypervisor_patch_cachetlbops:
 	sethi		%hi(__hypervisor_xcall_flush_tlb_mm), %o1
 	or		%o1, %lo(__hypervisor_xcall_flush_tlb_mm), %o1
 	call		tlb_patch_one
-	 mov		21, %o2
+	 mov		24, %o2
 
 	sethi		%hi(xcall_flush_tlb_page), %o0
 	or		%o0, %lo(xcall_flush_tlb_page), %o0
 	sethi		%hi(__hypervisor_xcall_flush_tlb_page), %o1
 	or		%o1, %lo(__hypervisor_xcall_flush_tlb_page), %o1
 	call		tlb_patch_one
-	 mov		17, %o2
+	 mov		20, %o2
 
 	sethi		%hi(xcall_flush_tlb_kernel_range), %o0
 	or		%o0, %lo(xcall_flush_tlb_kernel_range), %o0
 	sethi		%hi(__hypervisor_xcall_flush_tlb_kernel_range), %o1
 	or		%o1, %lo(__hypervisor_xcall_flush_tlb_kernel_range), %o1
 	call		tlb_patch_one
-	 mov		25, %o2
+	 mov		28, %o2
 #endif /* CONFIG_SMP */
 
 	ret
-- 
2.10.2