diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 902ecd92a29fb..dfbe9fdf97e40 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2251,6 +2251,8 @@
 			no_x2apic_optout
 				BIOS x2APIC opt-out request will be ignored
 			nopost	disable Interrupt Posting
+			posted_msi
+				enable MSIs delivered as posted interrupts
 
 	iomem=		Disable strict checking of access to MMIO memory
 		strict	regions from userspace.
diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 7a2ed154a5e1f..5036f13ab69f6 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -50,6 +50,13 @@ static inline struct irq_domain *arch_get_ir_parent_domain(void)
 	return x86_vector_domain;
 }
 
+extern bool enable_posted_msi;
+
+static inline bool posted_msi_supported(void)
+{
+	return enable_posted_msi && irq_remapping_cap(IRQ_POSTING_CAP);
+}
+
 #else  /* CONFIG_IRQ_REMAP */
 
 static inline bool irq_remapping_cap(enum irq_remap_cap cap) { return 0; }
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index ee59647c20501..056fec6991bc8 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -24,6 +24,8 @@ int no_x2apic_optout;
 
 int disable_irq_post = 0;
 
+bool enable_posted_msi __ro_after_init;
+
 static int disable_irq_remap;
 static struct irq_remap_ops *remap_ops;
 
@@ -70,7 +72,8 @@ static __init int setup_irqremap(char *str)
 			no_x2apic_optout = 1;
 		else if (!strncmp(str, "nopost", 6))
 			disable_irq_post = 1;
-
+		else if (IS_ENABLED(CONFIG_X86_POSTED_MSI) && !strncmp(str, "posted_msi", 10))
+			enable_posted_msi = true;
 		str += strcspn(str, ",");
 		while (*str == ',')
 			str++;