6.13-stable review patch. If anyone has any objections, please let me know.
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From: Sean Christopherson seanjc@google.com
commit 688124cc541f60d26a7547f45637b23dada4e527 upstream.
Don't overwrite an IRTE that is posting IRQs to a vCPU with a posted MSI entry if the host IRQ affinity happens to change. If/when the IRTE is reverted back to "host mode", it will be reconfigured as a posted MSI or remapped entry as appropriate.
Drop the "mode" field, which doesn't differentiate between posted MSIs and posted vCPUs, in favor of a dedicated posted_vcpu flag. Note! The two posted_{msi,vcpu} flags are intentionally not mutually exclusive; an IRTE can transition between posted MSI and posted vCPU.
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/20250315025135.2365846-3-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 | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-)
--- a/drivers/iommu/intel/irq_remapping.c +++ b/drivers/iommu/intel/irq_remapping.c @@ -26,11 +26,6 @@ #include "../iommu-pages.h" #include "cap_audit.h"
-enum irq_mode { - IRQ_REMAPPING, - IRQ_POSTING, -}; - struct ioapic_scope { struct intel_iommu *iommu; unsigned int id; @@ -50,8 +45,8 @@ struct irq_2_iommu { u16 irte_index; u16 sub_handle; u8 irte_mask; - enum irq_mode mode; bool posted_msi; + bool posted_vcpu; };
struct intel_ir_data { @@ -139,7 +134,6 @@ static int alloc_irte(struct intel_iommu irq_iommu->irte_index = index; irq_iommu->sub_handle = 0; irq_iommu->irte_mask = mask; - irq_iommu->mode = IRQ_REMAPPING; } raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
@@ -194,8 +188,6 @@ static int modify_irte(struct irq_2_iomm
rc = qi_flush_iec(iommu, index, 0);
- /* Update iommu mode according to the IRTE mode */ - irq_iommu->mode = irte->pst ? IRQ_POSTING : IRQ_REMAPPING; raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
return rc; @@ -1177,9 +1169,18 @@ static void __intel_ir_reconfigure_irte( { struct intel_ir_data *ir_data = irqd->chip_data;
+ /* + * Don't modify IRTEs for IRQs that are being posted to vCPUs if the + * host CPU affinity changes. + */ + if (ir_data->irq_2_iommu.posted_vcpu && !force_host) + return; + + ir_data->irq_2_iommu.posted_vcpu = false; + 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) + else modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry); }
@@ -1274,6 +1275,7 @@ static int intel_ir_set_vcpu_affinity(st irte_pi.pda_h = (vcpu_pi_info->pi_desc_addr >> 32) & ~(-1UL << PDA_HIGH_BIT);
+ ir_data->irq_2_iommu.posted_vcpu = true; modify_irte(&ir_data->irq_2_iommu, &irte_pi); }
@@ -1501,6 +1503,9 @@ static void intel_irq_remapping_deactiva struct intel_ir_data *data = irq_data->chip_data; struct irte entry;
+ WARN_ON_ONCE(data->irq_2_iommu.posted_vcpu); + data->irq_2_iommu.posted_vcpu = false; + memset(&entry, 0, sizeof(entry)); modify_irte(&data->irq_2_iommu, &entry); }