From c1d993341e46867af9412cf7f93f535895bbe3a7 Mon Sep 17 00:00:00 2001 From: Feng Wu Date: Tue, 9 Jun 2015 13:20:37 +0800 Subject: [PATCH] iommu, x86: Properly handle posted interrupts for IOMMU hotplug Return error when inserting a new IOMMU which doesn't support posted interrupts if posted interrupts are already enabled. Signed-off-by: Feng Wu Reviewed-by: Thomas Gleixner Acked-by: Joerg Roedel Cc: jiang.liu@linux.intel.com Cc: iommu@lists.linux-foundation.org Cc: dwmw2@infradead.org Link: http://lkml.kernel.org/r/1433827237-3382-11-git-send-email-feng.wu@intel.com Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 0f57af72d8f8..80f1d1486247 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -1355,6 +1355,9 @@ int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert) return -EINVAL; if (!ecap_ir_support(iommu->ecap)) return 0; + if (irq_remapping_cap(IRQ_POSTING_CAP) && + !cap_pi_support(iommu->cap)) + return -EBUSY; if (insert) { if (!iommu->ir_table) -- 2.20.1