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Message-ID: <158125695732.26104.8703656786037209247.tglx@nanos.tec.linutronix.de>
Date:   Sun, 09 Feb 2020 14:02:37 -0000
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     linux-kernel@...r.kernel.org, x86@...nel.org
Subject: [GIT pull] x86 fixes for 5.6-rc1

Linus,

please pull the latest x86/urgent branch from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-2020-02-09

up to:  0f378d73d429: x86/apic: Mask IOAPIC entries when disabling the local APIC


A set of fixes for X86:

 - Ensure that the PIT is set up when the local APIC is disable or
   configured in legacy mode. This is caused by an ordering issue
   introduced in the recent changes which skip PIT initialization when the
   TSC and APIC frequencies are already known.

 - Handle malformed SRAT tables during early ACPI parsing which caused an
   infinite loop anda boot hang.

 - Fix a long standing race in the affinity setting code which affects PCI
   devices with non-maskable MSI interrupts. The problem is caused by the
   non-atomic writes of the MSI address (destination APIC id) and data
   (vector) fields which the device uses to construct the MSI message. The
   non-atomic writes are mandated by PCI.

   If both fields change and the device raises an interrupt after writing
   address and before writing data, then the MSI block constructs a
   inconsistent message which causes interrupts to be lost and subsequent
   malfunction of the device.

   The fix is to redirect the interrupt to the new vector on the current
   CPU first and then switch it over to the new target CPU. This allows to
   observe an eventually raised interrupt in the transitional stage (old
   CPU, new vector) to be observed in the APIC IRR and retriggered on the
   new target CPU and the new vector. The potential spurious interrupts
   caused by this are harmless and can in the worst case expose a buggy
   driver (all handlers have to be able to deal with spurious interrupts as
   they can and do happen for various reasons).

 - Add the missing suspend/resume mechanism for the HYPERV hypercall page
   which prevents resume hibernation on HYPERV guests. This change got
   lost before the merge window.

 - Mask the IOAPIC before disabling the local APIC to prevent potentially
   stale IOAPIC remote IRR bits which cause stale interrupt lines after
   resume.

Thanks,

	tglx

------------------>
Dexuan Cui (1):
      x86/hyperv: Suspend/resume the hypercall page for hibernation

Steven Clarkson (1):
      x86/boot: Handle malformed SRAT tables during early ACPI parsing

Thomas Gleixner (2):
      x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
      x86/apic/msi: Plug non-maskable MSI affinity race

Tony W Wang-oc (1):
      x86/apic: Mask IOAPIC entries when disabling the local APIC


 arch/x86/boot/compressed/acpi.c |   6 ++
 arch/x86/hyperv/hv_init.c       |  50 ++++++++++++++++
 arch/x86/include/asm/apic.h     |  10 ++++
 arch/x86/include/asm/x86_init.h |   2 +
 arch/x86/kernel/apic/apic.c     |  30 ++++++++--
 arch/x86/kernel/apic/msi.c      | 128 +++++++++++++++++++++++++++++++++++++++-
 arch/x86/kernel/time.c          |  12 +++-
 arch/x86/kernel/x86_init.c      |   1 +
 arch/x86/xen/enlighten_pv.c     |   1 +
 include/linux/irq.h             |  18 ++++++
 include/linux/irqdomain.h       |   7 +++
 kernel/irq/debugfs.c            |   1 +
 kernel/irq/msi.c                |   5 +-
 13 files changed, 260 insertions(+), 11 deletions(-)

diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
index 25019d42ae93..ef2ad7253cd5 100644
--- a/arch/x86/boot/compressed/acpi.c
+++ b/arch/x86/boot/compressed/acpi.c
@@ -393,7 +393,13 @@ int count_immovable_mem_regions(void)
 	table = table_addr + sizeof(struct acpi_table_srat);
 
 	while (table + sizeof(struct acpi_subtable_header) < table_end) {
+
 		sub_table = (struct acpi_subtable_header *)table;
+		if (!sub_table->length) {
+			debug_putstr("Invalid zero length SRAT subtable.\n");
+			return 0;
+		}
+
 		if (sub_table->type == ACPI_SRAT_TYPE_MEMORY_AFFINITY) {
 			struct acpi_srat_mem_affinity *ma;
 
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index caaf4dce99bf..b0da5320bcff 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -21,11 +21,15 @@
 #include <linux/hyperv.h>
 #include <linux/slab.h>
 #include <linux/cpuhotplug.h>
+#include <linux/syscore_ops.h>
 #include <clocksource/hyperv_timer.h>
 
 void *hv_hypercall_pg;
 EXPORT_SYMBOL_GPL(hv_hypercall_pg);
 
+/* Storage to save the hypercall page temporarily for hibernation */
+static void *hv_hypercall_pg_saved;
+
 u32 *hv_vp_index;
 EXPORT_SYMBOL_GPL(hv_vp_index);
 
@@ -246,6 +250,48 @@ static int __init hv_pci_init(void)
 	return 1;
 }
 
+static int hv_suspend(void)
+{
+	union hv_x64_msr_hypercall_contents hypercall_msr;
+
+	/*
+	 * Reset the hypercall page as it is going to be invalidated
+	 * accross hibernation. Setting hv_hypercall_pg to NULL ensures
+	 * that any subsequent hypercall operation fails safely instead of
+	 * crashing due to an access of an invalid page. The hypercall page
+	 * pointer is restored on resume.
+	 */
+	hv_hypercall_pg_saved = hv_hypercall_pg;
+	hv_hypercall_pg = NULL;
+
+	/* Disable the hypercall page in the hypervisor */
+	rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+	hypercall_msr.enable = 0;
+	wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+	return 0;
+}
+
+static void hv_resume(void)
+{
+	union hv_x64_msr_hypercall_contents hypercall_msr;
+
+	/* Re-enable the hypercall page */
+	rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+	hypercall_msr.enable = 1;
+	hypercall_msr.guest_physical_address =
+		vmalloc_to_pfn(hv_hypercall_pg_saved);
+	wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+	hv_hypercall_pg = hv_hypercall_pg_saved;
+	hv_hypercall_pg_saved = NULL;
+}
+
+static struct syscore_ops hv_syscore_ops = {
+	.suspend	= hv_suspend,
+	.resume		= hv_resume,
+};
+
 /*
  * This function is to be invoked early in the boot sequence after the
  * hypervisor has been detected.
@@ -330,6 +376,8 @@ void __init hyperv_init(void)
 
 	x86_init.pci.arch_init = hv_pci_init;
 
+	register_syscore_ops(&hv_syscore_ops);
+
 	return;
 
 remove_cpuhp_state:
@@ -349,6 +397,8 @@ void hyperv_cleanup(void)
 {
 	union hv_x64_msr_hypercall_contents hypercall_msr;
 
+	unregister_syscore_ops(&hv_syscore_ops);
+
 	/* Reset our OS id */
 	wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
 
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 2ebc17d9c72c..19e94af9cc5d 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -140,6 +140,7 @@ extern void apic_soft_disable(void);
 extern void lapic_shutdown(void);
 extern void sync_Arb_IDs(void);
 extern void init_bsp_APIC(void);
+extern void apic_intr_mode_select(void);
 extern void apic_intr_mode_init(void);
 extern void init_apic_mappings(void);
 void register_lapic_address(unsigned long address);
@@ -188,6 +189,7 @@ static inline void disable_local_APIC(void) { }
 # define setup_secondary_APIC_clock x86_init_noop
 static inline void lapic_update_tsc_freq(void) { }
 static inline void init_bsp_APIC(void) { }
+static inline void apic_intr_mode_select(void) { }
 static inline void apic_intr_mode_init(void) { }
 static inline void lapic_assign_system_vectors(void) { }
 static inline void lapic_assign_legacy_vector(unsigned int i, bool r) { }
@@ -452,6 +454,14 @@ static inline void ack_APIC_irq(void)
 	apic_eoi();
 }
 
+
+static inline bool lapic_vector_set_in_irr(unsigned int vector)
+{
+	u32 irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
+
+	return !!(irr & (1U << (vector % 32)));
+}
+
 static inline unsigned default_get_apic_id(unsigned long x)
 {
 	unsigned int ver = GET_APIC_VERSION(apic_read(APIC_LVR));
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index 19435858df5f..96d9cd208610 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -51,12 +51,14 @@ struct x86_init_resources {
  *				are set up.
  * @intr_init:			interrupt init code
  * @trap_init:			platform specific trap setup
+ * @intr_mode_select:		interrupt delivery mode selection
  * @intr_mode_init:		interrupt delivery mode setup
  */
 struct x86_init_irqs {
 	void (*pre_vector_init)(void);
 	void (*intr_init)(void);
 	void (*trap_init)(void);
+	void (*intr_mode_select)(void);
 	void (*intr_mode_init)(void);
 };
 
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 28446fa6bf18..5f973fed3c9f 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -830,8 +830,17 @@ bool __init apic_needs_pit(void)
 	if (!tsc_khz || !cpu_khz)
 		return true;
 
-	/* Is there an APIC at all? */
-	if (!boot_cpu_has(X86_FEATURE_APIC))
+	/* Is there an APIC at all or is it disabled? */
+	if (!boot_cpu_has(X86_FEATURE_APIC) || disable_apic)
+		return true;
+
+	/*
+	 * If interrupt delivery mode is legacy PIC or virtual wire without
+	 * configuration, the local APIC timer wont be set up. Make sure
+	 * that the PIT is initialized.
+	 */
+	if (apic_intr_mode == APIC_PIC ||
+	    apic_intr_mode == APIC_VIRTUAL_WIRE_NO_CONFIG)
 		return true;
 
 	/* Virt guests may lack ARAT, but still have DEADLINE */
@@ -1322,7 +1331,7 @@ void __init sync_Arb_IDs(void)
 
 enum apic_intr_mode_id apic_intr_mode __ro_after_init;
 
-static int __init apic_intr_mode_select(void)
+static int __init __apic_intr_mode_select(void)
 {
 	/* Check kernel option */
 	if (disable_apic) {
@@ -1384,6 +1393,12 @@ static int __init apic_intr_mode_select(void)
 	return APIC_SYMMETRIC_IO;
 }
 
+/* Select the interrupt delivery mode for the BSP */
+void __init apic_intr_mode_select(void)
+{
+	apic_intr_mode = __apic_intr_mode_select();
+}
+
 /*
  * An initial setup of the virtual wire mode.
  */
@@ -1440,8 +1455,6 @@ void __init apic_intr_mode_init(void)
 {
 	bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
 
-	apic_intr_mode = apic_intr_mode_select();
-
 	switch (apic_intr_mode) {
 	case APIC_PIC:
 		pr_info("APIC: Keep in PIC mode(8259)\n");
@@ -2626,6 +2639,13 @@ static int lapic_suspend(void)
 #endif
 
 	local_irq_save(flags);
+
+	/*
+	 * Mask IOAPIC before disabling the local APIC to prevent stale IRR
+	 * entries on some implementations.
+	 */
+	mask_ioapic_entries();
+
 	disable_local_APIC();
 
 	irq_remapping_disable();
diff --git a/arch/x86/kernel/apic/msi.c b/arch/x86/kernel/apic/msi.c
index 7f7533462474..159bd0cb8548 100644
--- a/arch/x86/kernel/apic/msi.c
+++ b/arch/x86/kernel/apic/msi.c
@@ -23,10 +23,8 @@
 
 static struct irq_domain *msi_default_domain;
 
-static void irq_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
+static void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg)
 {
-	struct irq_cfg *cfg = irqd_cfg(data);
-
 	msg->address_hi = MSI_ADDR_BASE_HI;
 
 	if (x2apic_enabled())
@@ -47,6 +45,127 @@ static void irq_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
 		MSI_DATA_VECTOR(cfg->vector);
 }
 
+static void irq_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
+{
+	__irq_msi_compose_msg(irqd_cfg(data), msg);
+}
+
+static void irq_msi_update_msg(struct irq_data *irqd, struct irq_cfg *cfg)
+{
+	struct msi_msg msg[2] = { [1] = { }, };
+
+	__irq_msi_compose_msg(cfg, msg);
+	irq_data_get_irq_chip(irqd)->irq_write_msi_msg(irqd, msg);
+}
+
+static int
+msi_set_affinity(struct irq_data *irqd, const struct cpumask *mask, bool force)
+{
+	struct irq_cfg old_cfg, *cfg = irqd_cfg(irqd);
+	struct irq_data *parent = irqd->parent_data;
+	unsigned int cpu;
+	int ret;
+
+	/* Save the current configuration */
+	cpu = cpumask_first(irq_data_get_effective_affinity_mask(irqd));
+	old_cfg = *cfg;
+
+	/* Allocate a new target vector */
+	ret = parent->chip->irq_set_affinity(parent, mask, force);
+	if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
+		return ret;
+
+	/*
+	 * For non-maskable and non-remapped MSI interrupts the migration
+	 * to a different destination CPU and a different vector has to be
+	 * done careful to handle the possible stray interrupt which can be
+	 * caused by the non-atomic update of the address/data pair.
+	 *
+	 * Direct update is possible when:
+	 * - The MSI is maskable (remapped MSI does not use this code path)).
+	 *   The quirk bit is not set in this case.
+	 * - The new vector is the same as the old vector
+	 * - The old vector is MANAGED_IRQ_SHUTDOWN_VECTOR (interrupt starts up)
+	 * - The new destination CPU is the same as the old destination CPU
+	 */
+	if (!irqd_msi_nomask_quirk(irqd) ||
+	    cfg->vector == old_cfg.vector ||
+	    old_cfg.vector == MANAGED_IRQ_SHUTDOWN_VECTOR ||
+	    cfg->dest_apicid == old_cfg.dest_apicid) {
+		irq_msi_update_msg(irqd, cfg);
+		return ret;
+	}
+
+	/*
+	 * Paranoia: Validate that the interrupt target is the local
+	 * CPU.
+	 */
+	if (WARN_ON_ONCE(cpu != smp_processor_id())) {
+		irq_msi_update_msg(irqd, cfg);
+		return ret;
+	}
+
+	/*
+	 * Redirect the interrupt to the new vector on the current CPU
+	 * first. This might cause a spurious interrupt on this vector if
+	 * the device raises an interrupt right between this update and the
+	 * update to the final destination CPU.
+	 *
+	 * If the vector is in use then the installed device handler will
+	 * denote it as spurious which is no harm as this is a rare event
+	 * and interrupt handlers have to cope with spurious interrupts
+	 * anyway. If the vector is unused, then it is marked so it won't
+	 * trigger the 'No irq handler for vector' warning in do_IRQ().
+	 *
+	 * This requires to hold vector lock to prevent concurrent updates to
+	 * the affected vector.
+	 */
+	lock_vector_lock();
+
+	/*
+	 * Mark the new target vector on the local CPU if it is currently
+	 * unused. Reuse the VECTOR_RETRIGGERED state which is also used in
+	 * the CPU hotplug path for a similar purpose. This cannot be
+	 * undone here as the current CPU has interrupts disabled and
+	 * cannot handle the interrupt before the whole set_affinity()
+	 * section is done. In the CPU unplug case, the current CPU is
+	 * about to vanish and will not handle any interrupts anymore. The
+	 * vector is cleaned up when the CPU comes online again.
+	 */
+	if (IS_ERR_OR_NULL(this_cpu_read(vector_irq[cfg->vector])))
+		this_cpu_write(vector_irq[cfg->vector], VECTOR_RETRIGGERED);
+
+	/* Redirect it to the new vector on the local CPU temporarily */
+	old_cfg.vector = cfg->vector;
+	irq_msi_update_msg(irqd, &old_cfg);
+
+	/* Now transition it to the target CPU */
+	irq_msi_update_msg(irqd, cfg);
+
+	/*
+	 * All interrupts after this point are now targeted at the new
+	 * vector/CPU.
+	 *
+	 * Drop vector lock before testing whether the temporary assignment
+	 * to the local CPU was hit by an interrupt raised in the device,
+	 * because the retrigger function acquires vector lock again.
+	 */
+	unlock_vector_lock();
+
+	/*
+	 * Check whether the transition raced with a device interrupt and
+	 * is pending in the local APICs IRR. It is safe to do this outside
+	 * of vector lock as the irq_desc::lock of this interrupt is still
+	 * held and interrupts are disabled: The check is not accessing the
+	 * underlying vector store. It's just checking the local APIC's
+	 * IRR.
+	 */
+	if (lapic_vector_set_in_irr(cfg->vector))
+		irq_data_get_irq_chip(irqd)->irq_retrigger(irqd);
+
+	return ret;
+}
+
 /*
  * IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
  * which implement the MSI or MSI-X Capability Structure.
@@ -58,6 +177,7 @@ static struct irq_chip pci_msi_controller = {
 	.irq_ack		= irq_chip_ack_parent,
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_compose_msi_msg	= irq_msi_compose_msg,
+	.irq_set_affinity	= msi_set_affinity,
 	.flags			= IRQCHIP_SKIP_SET_WAKE,
 };
 
@@ -146,6 +266,8 @@ void __init arch_init_msi_domain(struct irq_domain *parent)
 	}
 	if (!msi_default_domain)
 		pr_warn("failed to initialize irqdomain for MSI/MSI-x.\n");
+	else
+		msi_default_domain->flags |= IRQ_DOMAIN_MSI_NOMASK_QUIRK;
 }
 
 #ifdef CONFIG_IRQ_REMAP
diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
index 7ce29cee9f9e..d8673d8a779b 100644
--- a/arch/x86/kernel/time.c
+++ b/arch/x86/kernel/time.c
@@ -91,10 +91,18 @@ void __init hpet_time_init(void)
 
 static __init void x86_late_time_init(void)
 {
+	/*
+	 * Before PIT/HPET init, select the interrupt mode. This is required
+	 * to make the decision whether PIT should be initialized correct.
+	 */
+	x86_init.irqs.intr_mode_select();
+
+	/* Setup the legacy timers */
 	x86_init.timers.timer_init();
+
 	/*
-	 * After PIT/HPET timers init, select and setup
-	 * the final interrupt mode for delivering IRQs.
+	 * After PIT/HPET timers init, set up the final interrupt mode for
+	 * delivering IRQs.
 	 */
 	x86_init.irqs.intr_mode_init();
 	tsc_init();
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index ce89430a7f80..9a89261dcd2a 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -80,6 +80,7 @@ struct x86_init_ops x86_init __initdata = {
 		.pre_vector_init	= init_ISA_irqs,
 		.intr_init		= native_init_IRQ,
 		.trap_init		= x86_init_noop,
+		.intr_mode_select	= apic_intr_mode_select,
 		.intr_mode_init		= apic_intr_mode_init
 	},
 
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index ae4a41ca19f6..1f756ffffe8b 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -1205,6 +1205,7 @@ asmlinkage __visible void __init xen_start_kernel(void)
 	x86_platform.get_nmi_reason = xen_get_nmi_reason;
 
 	x86_init.resources.memory_setup = xen_memory_setup;
+	x86_init.irqs.intr_mode_select	= x86_init_noop;
 	x86_init.irqs.intr_mode_init	= x86_init_noop;
 	x86_init.oem.arch_setup = xen_arch_setup;
 	x86_init.oem.banner = xen_banner;
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 7853eb9301f2..3ed5a055b5f4 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -209,6 +209,8 @@ struct irq_data {
  * IRQD_SINGLE_TARGET		- IRQ allows only a single affinity target
  * IRQD_DEFAULT_TRIGGER_SET	- Expected trigger already been set
  * IRQD_CAN_RESERVE		- Can use reservation mode
+ * IRQD_MSI_NOMASK_QUIRK	- Non-maskable MSI quirk for affinity change
+ *				  required
  */
 enum {
 	IRQD_TRIGGER_MASK		= 0xf,
@@ -231,6 +233,7 @@ enum {
 	IRQD_SINGLE_TARGET		= (1 << 24),
 	IRQD_DEFAULT_TRIGGER_SET	= (1 << 25),
 	IRQD_CAN_RESERVE		= (1 << 26),
+	IRQD_MSI_NOMASK_QUIRK		= (1 << 27),
 };
 
 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
@@ -390,6 +393,21 @@ static inline bool irqd_can_reserve(struct irq_data *d)
 	return __irqd_to_state(d) & IRQD_CAN_RESERVE;
 }
 
+static inline void irqd_set_msi_nomask_quirk(struct irq_data *d)
+{
+	__irqd_to_state(d) |= IRQD_MSI_NOMASK_QUIRK;
+}
+
+static inline void irqd_clr_msi_nomask_quirk(struct irq_data *d)
+{
+	__irqd_to_state(d) &= ~IRQD_MSI_NOMASK_QUIRK;
+}
+
+static inline bool irqd_msi_nomask_quirk(struct irq_data *d)
+{
+	return __irqd_to_state(d) & IRQD_MSI_NOMASK_QUIRK;
+}
+
 #undef __irqd_to_state
 
 static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d)
diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 3c340dbc5a1f..4da8df57618a 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -206,6 +206,13 @@ enum {
 	/* Irq domain implements MSI remapping */
 	IRQ_DOMAIN_FLAG_MSI_REMAP	= (1 << 5),
 
+	/*
+	 * Quirk to handle MSI implementations which do not provide
+	 * masking. Currently known to affect x86, but partially
+	 * handled in core code.
+	 */
+	IRQ_DOMAIN_MSI_NOMASK_QUIRK	= (1 << 6),
+
 	/*
 	 * Flags starting from IRQ_DOMAIN_FLAG_NONCORE are reserved
 	 * for implementation specific purposes and ignored by the
diff --git a/kernel/irq/debugfs.c b/kernel/irq/debugfs.c
index c1eccd4f6520..a949bd39e343 100644
--- a/kernel/irq/debugfs.c
+++ b/kernel/irq/debugfs.c
@@ -114,6 +114,7 @@ static const struct irq_bit_descr irqdata_states[] = {
 	BIT_MASK_DESCR(IRQD_AFFINITY_MANAGED),
 	BIT_MASK_DESCR(IRQD_MANAGED_SHUTDOWN),
 	BIT_MASK_DESCR(IRQD_CAN_RESERVE),
+	BIT_MASK_DESCR(IRQD_MSI_NOMASK_QUIRK),
 
 	BIT_MASK_DESCR(IRQD_FORWARDED_TO_VCPU),
 
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index ad26fbcfbfc8..eb95f6106a1e 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -453,8 +453,11 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
 			continue;
 
 		irq_data = irq_domain_get_irq_data(domain, desc->irq);
-		if (!can_reserve)
+		if (!can_reserve) {
 			irqd_clr_can_reserve(irq_data);
+			if (domain->flags & IRQ_DOMAIN_MSI_NOMASK_QUIRK)
+				irqd_set_msi_nomask_quirk(irq_data);
+		}
 		ret = irq_domain_activate_irq(irq_data, can_reserve);
 		if (ret)
 			goto cleanup;

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