This is a note to let you know that I've just added the patch titled
KVM: PPC: Book3S: Fix server always zero from kvmppc_xive_get_xive()
to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-ppc-book3s-fix-server-always-zero-from-kvmppc_xive_get_xive.patch
and it can be found in the queue-4.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 2fb1e946450a4fef74bb72f360555f7760d816f0 Mon Sep 17 00:00:00 2001
From: Sam Bobroff <sam.bobroff@xxxxxxxxxxx>
Date: Tue, 26 Sep 2017 16:47:04 +1000
Subject: KVM: PPC: Book3S: Fix server always zero from kvmppc_xive_get_xive()
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From: Sam Bobroff <sam.bobroff@xxxxxxxxxxx>
commit 2fb1e946450a4fef74bb72f360555f7760d816f0 upstream.
In KVM's XICS-on-XIVE emulation, kvmppc_xive_get_xive() returns the
value of state->guest_server as "server". However, this value is not
set by it's counterpart kvmppc_xive_set_xive(). When the guest uses
this interface to migrate interrupts away from a CPU that is going
offline, it sees all interrupts as belonging to CPU 0, so they are
left assigned to (now) offline CPUs.
This patch removes the guest_server field from the state, and returns
act_server in it's place (that is, the CPU actually handling the
interrupt, which may differ from the one requested).
Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Signed-off-by: Sam Bobroff <sam.bobroff@xxxxxxxxxxx>
Acked-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/kvm/book3s_xive.c | 5 ++---
arch/powerpc/kvm/book3s_xive.h | 1 -
2 files changed, 2 insertions(+), 4 deletions(-)
--- a/arch/powerpc/kvm/book3s_xive.c
+++ b/arch/powerpc/kvm/book3s_xive.c
@@ -622,7 +622,7 @@ int kvmppc_xive_get_xive(struct kvm *kvm
return -EINVAL;
state = &sb->irq_state[idx];
arch_spin_lock(&sb->lock);
- *server = state->guest_server;
+ *server = state->act_server;
*priority = state->guest_priority;
arch_spin_unlock(&sb->lock);
@@ -1331,7 +1331,7 @@ static int xive_get_source(struct kvmppc
xive->saved_src_count++;
/* Convert saved state into something compatible with xics */
- val = state->guest_server;
+ val = state->act_server;
prio = state->saved_scan_prio;
if (prio == MASKED) {
@@ -1507,7 +1507,6 @@ static int xive_set_source(struct kvmppc
/* First convert prio and mark interrupt as untargetted */
act_prio = xive_prio_from_guest(guest_prio);
state->act_priority = MASKED;
- state->guest_server = server;
/*
* We need to drop the lock due to the mutex below. Hopefully
--- a/arch/powerpc/kvm/book3s_xive.h
+++ b/arch/powerpc/kvm/book3s_xive.h
@@ -35,7 +35,6 @@ struct kvmppc_xive_irq_state {
struct xive_irq_data *pt_data; /* XIVE Pass-through associated data */
/* Targetting as set by guest */
- u32 guest_server; /* Current guest selected target */
u8 guest_priority; /* Guest set priority */
u8 saved_priority; /* Saved priority when masking */
Patches currently in stable-queue which might be from sam.bobroff@xxxxxxxxxxx are
queue-4.13/kvm-ppc-book3s-fix-server-always-zero-from-kvmppc_xive_get_xive.patch