6.14-stable review patch. If anyone has any objections, please let me know.
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From: Sean Christopherson seanjc@google.com
commit 2454823e97a63d85a6b215905f71e5a06324eab7 upstream.
Add a helper to take care of reconfiguring an IRTE to deliver IRQs to the host, i.e. not to a vCPU, and use the helper when an IRTE's vCPU affinity is nullified, i.e. when KVM puts an IRTE back into "host" mode. Because posted MSIs use an ephemeral IRTE, using modify_irte() puts the IRTE into full remapped mode, i.e. unintentionally disables posted MSIs on the IRQ.
Fixes: ed1e48ea4370 ("iommu/vt-d: Enable posted mode for device MSIs") Cc: stable@vger.kernel.org Cc: Thomas Gleixner tglx@linutronix.de Cc: Jacob Pan jacob.jun.pan@linux.intel.com Signed-off-by: Sean Christopherson seanjc@google.com Link: https://lore.kernel.org/r/20250315025135.2365846-2-seanjc@google.com Signed-off-by: Lu Baolu baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/intel/irq_remapping.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-)
--- a/drivers/iommu/intel/irq_remapping.c +++ b/drivers/iommu/intel/irq_remapping.c @@ -1169,7 +1169,17 @@ static void intel_ir_reconfigure_irte_po static inline void intel_ir_reconfigure_irte_posted(struct irq_data *irqd) {} #endif
-static void intel_ir_reconfigure_irte(struct irq_data *irqd, bool force) +static void __intel_ir_reconfigure_irte(struct irq_data *irqd, bool force_host) +{ + struct intel_ir_data *ir_data = irqd->chip_data; + + if (ir_data->irq_2_iommu.posted_msi) + intel_ir_reconfigure_irte_posted(irqd); + else if (force_host || ir_data->irq_2_iommu.mode == IRQ_REMAPPING) + modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry); +} + +static void intel_ir_reconfigure_irte(struct irq_data *irqd, bool force_host) { struct intel_ir_data *ir_data = irqd->chip_data; struct irte *irte = &ir_data->irte_entry; @@ -1182,10 +1192,7 @@ static void intel_ir_reconfigure_irte(st irte->vector = cfg->vector; irte->dest_id = IRTE_DEST(cfg->dest_apicid);
- if (ir_data->irq_2_iommu.posted_msi) - intel_ir_reconfigure_irte_posted(irqd); - else if (force || ir_data->irq_2_iommu.mode == IRQ_REMAPPING) - modify_irte(&ir_data->irq_2_iommu, irte); + __intel_ir_reconfigure_irte(irqd, force_host); }
/* @@ -1240,7 +1247,7 @@ static int intel_ir_set_vcpu_affinity(st
/* stop posting interrupts, back to the default mode */ if (!vcpu_pi_info) { - modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry); + __intel_ir_reconfigure_irte(data, true); } else { struct irte irte_pi;