diff options
| author | Jason Andryuk <jason.andryuk@amd.com> | 2025-10-17 09:41:17 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-10-19 16:23:23 +0200 |
| commit | b8291d6d98545d954f3d7fa46f5655e2b8a23973 (patch) | |
| tree | 4cc79fb74b8198ec48e7305b18e4906c55a54078 | |
| parent | db62b1e7b1d3f8e97b59f9f8e07829356d0ff3e4 (diff) | |
xen/events: Update virq_to_irq on migration
[ Upstream commit 3fcc8e146935415d69ffabb5df40ecf50e106131 ]
VIRQs come in 3 flavors, per-VPU, per-domain, and global, and the VIRQs
are tracked in per-cpu virq_to_irq arrays.
Per-domain and global VIRQs must be bound on CPU 0, and
bind_virq_to_irq() sets the per_cpu virq_to_irq at registration time
Later, the interrupt can migrate, and info->cpu is updated. When
calling __unbind_from_irq(), the per-cpu virq_to_irq is cleared for a
different cpu. If bind_virq_to_irq() is called again with CPU 0, the
stale irq is returned. There won't be any irq_info for the irq, so
things break.
Make xen_rebind_evtchn_to_cpu() update the per_cpu virq_to_irq mappings
to keep them update to date with the current cpu. This ensures the
correct virq_to_irq is cleared in __unbind_from_irq().
Fixes: e46cdb66c8fc ("xen: event channels")
Cc: stable@vger.kernel.org
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20250828003604.8949-4-jason.andryuk@amd.com>
[ Adjust context ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/xen/events/events_base.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index c2e41d6cab9e..9052a4873bca 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -1807,9 +1807,20 @@ static int xen_rebind_evtchn_to_cpu(struct irq_info *info, unsigned int tcpu) * virq or IPI channel, which don't actually need to be rebound. Ignore * it, but don't do the xenlinux-level rebind in that case. */ - if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0) + if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0) { + int old_cpu = info->cpu; + bind_evtchn_to_cpu(evtchn, tcpu, false); + if (info->type == IRQT_VIRQ) { + int virq = info->u.virq; + int irq = per_cpu(virq_to_irq, old_cpu)[virq]; + + per_cpu(virq_to_irq, old_cpu)[virq] = -1; + per_cpu(virq_to_irq, tcpu)[virq] = irq; + } + } + do_unmask(info, EVT_MASK_REASON_TEMPORARY); return 0; |