lkml.org 
[lkml]   [2017]   [Dec]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.14 60/74] KVM: PPC: Book3S HV: Fix pending_pri value in kvmppc_xive_get_icp()
Date
4.14-stable review patch.  If anyone has any objections, please let me know.

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

From: Laurent Vivier <lvivier@redhat.com>

commit 7333b5aca412d6ad02667b5a513485838a91b136 upstream.

When we migrate a VM from a POWER8 host (XICS) to a POWER9 host
(XICS-on-XIVE), we have an error:

qemu-kvm: Unable to restore KVM interrupt controller state \
(0xff000000) for CPU 0: Invalid argument

This is because kvmppc_xics_set_icp() checks the new state
is internaly consistent, and especially:

...
1129 if (xisr == 0) {
1130 if (pending_pri != 0xff)
1131 return -EINVAL;
...

On the other side, kvmppc_xive_get_icp() doesn't set
neither the pending_pri value, nor the xisr value (set to 0)
(and kvmppc_xive_set_icp() ignores the pending_pri value)

As xisr is 0, pending_pri must be set to 0xff.

Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/powerpc/kvm/book3s_xive.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/powerpc/kvm/book3s_xive.c
+++ b/arch/powerpc/kvm/book3s_xive.c
@@ -725,7 +725,8 @@ u64 kvmppc_xive_get_icp(struct kvm_vcpu

/* Return the per-cpu state for state saving/migration */
return (u64)xc->cppr << KVM_REG_PPC_ICP_CPPR_SHIFT |
- (u64)xc->mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT;
+ (u64)xc->mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT |
+ (u64)0xff << KVM_REG_PPC_ICP_PPRI_SHIFT;
}

int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval)

\
 
 \ /
  Last update: 2017-12-27 17:56    [W:0.207 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site