[PATCH] KVM: PPC: Book3S HV: Branch inside feature section

Alexander Graf agraf at suse.de
Fri Feb 9 04:38:53 AEDT 2018


We ended up with code that did a conditional branch inside a feature
section to code outside of the feature section. Depending on how the
object file gets organized, that might mean we exceed the 14bit
relocation limit for conditional branches:

  arch/powerpc/kvm/built-in.o:arch/powerpc/kvm/book3s_hv_rmhandlers.S:416:(__ftr_alt_97+0x8): relocation truncated to fit: R_PPC64_REL14 against `.text'+1ca4

So instead of doing a conditional branch outside of the feature section,
let's just jump at the end of the same, making the branch very short.

Signed-off-by: Alexander Graf <agraf at suse.de>
---
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 9c61f736c75b..1e037326897b 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -413,10 +413,11 @@ FTR_SECTION_ELSE
 	/* On P9 we use the split_info for coordinating LPCR changes */
 	lwz	r4, KVM_SPLIT_DO_SET(r6)
 	cmpwi	r4, 0
-	beq	63f
+	beq	1f
 	mr	r3, r6
 	bl	kvmhv_p9_set_lpcr
 	nop
+1:
 ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 63:
 	/* Order load of vcpu after load of vcore */
-- 
2.12.3



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