[PATCH] powerpc/kvm: Fix guest boot issue DAWR cpu feature

[PATCH] powerpc/kvm: Fix guest boot issue DAWR cpu feature

[Aneesh Kumar K.V]

SLOF check the 'sc 1' support by issuing a hcall with H_SET_DABR. With
recent patch to make the hcall return H_UNSUPPORTED, we get guest boot
failures. SLOF can work with the hcall failure H_HARDWARE for the above
hcall. Switch the return value to H_HARDWARE instead of H_UNSUPPORTED so that
we don't break the guest boot.

Fixes: e8ebedbf ("KVM: PPC: Book3S HV: Return error from h_set_dabr() on POWER9")

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index c4c1b169826a..fdd7350d6c87 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -2576,7 +2576,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 2:
 BEGIN_FTR_SECTION
 	/* POWER9 with disabled DAWR */
-	li	r3, H_UNSUPPORTED
+	li	r3, H_HARDWARE
 	blr
 END_FTR_SECTION_IFCLR(CPU_FTR_DAWR)
 	/* Emulate H_SET_DABR/X on P8 for the sake of compat mode guests */
-- 
2.14.3

Re: powerpc/kvm: Fix guest boot issue DAWR cpu feature

[Michael Ellerman]

On Fri, 2018-03-30 at 11:57:24 UTC, "Aneesh Kumar K.V" wrote:
> SLOF check the 'sc 1' support by issuing a hcall with H_SET_DABR. With
> recent patch to make the hcall return H_UNSUPPORTED, we get guest boot
> failures. SLOF can work with the hcall failure H_HARDWARE for the above
> hcall. Switch the return value to H_HARDWARE instead of H_UNSUPPORTED so that
> we don't break the guest boot.
> 
> Fixes: e8ebedbf ("KVM: PPC: Book3S HV: Return error from h_set_dabr() on POWER9")
> 
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/ca9a16c3bc1582da62ef9c47fc2200

cheers