Merge tag 'irq-urgent-2021-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:
 "A set of fixes for PCI/MSI and x86 interrupt startup:

   - Mask all MSI-X entries when enabling MSI-X otherwise stale unmasked
     entries stay around e.g. when a crashkernel is booted.

   - Enforce masking of a MSI-X table entry when updating it, which
     mandatory according to speification

   - Ensure that writes to MSI[-X} tables are flushed.

   - Prevent invalid bits being set in the MSI mask register

   - Properly serialize modifications to the mask cache and the mask
     register for multi-MSI.

   - Cure the violation of the affinity setting rules on X86 during
     interrupt startup which can cause lost and stale interrupts. Move
     the initial affinity setting ahead of actualy enabling the
     interrupt.

   - Ensure that MSI interrupts are completely torn down before freeing
     them in the error handling case.

   - Prevent an array out of bounds access in the irq timings code"

* tag 'irq-urgent-2021-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  driver core: Add missing kernel doc for device::msi_lock
  genirq/msi: Ensure deactivation on teardown
  genirq/timings: Prevent potential array overflow in __irq_timings_store()
  x86/msi: Force affinity setup before startup
  x86/ioapic: Force affinity setup before startup
  genirq: Provide IRQCHIP_AFFINITY_PRE_STARTUP
  PCI/MSI: Protect msi_desc::masked for multi-MSI
  PCI/MSI: Use msi_mask_irq() in pci_msi_shutdown()
  PCI/MSI: Correct misleading comments
  PCI/MSI: Do not set invalid bits in MSI mask
  PCI/MSI: Enforce MSI[X] entry updates to be visible
  PCI/MSI: Enforce that MSI-X table entry is masked for update
  PCI/MSI: Mask all unused MSI-X entries
  PCI/MSI: Enable and mask MSI-X early

3 files changed, 13 insertions, 6 deletions

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index d5c691a3208b..39224e035e47 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1986,7 +1986,8 @@ static struct irq_chip ioapic_chip __read_mostly = {
 	.irq_set_affinity	= ioapic_set_affinity,
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
-	.flags			= IRQCHIP_SKIP_SET_WAKE,
+	.flags			= IRQCHIP_SKIP_SET_WAKE |
+				  IRQCHIP_AFFINITY_PRE_STARTUP,
 };
 
 static struct irq_chip ioapic_ir_chip __read_mostly = {
@@ -1999,7 +2000,8 @@ static struct irq_chip ioapic_ir_chip __read_mostly = {
 	.irq_set_affinity	= ioapic_set_affinity,
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_get_irqchip_state	= ioapic_irq_get_chip_state,
-	.flags			= IRQCHIP_SKIP_SET_WAKE,
+	.flags			= IRQCHIP_SKIP_SET_WAKE |
+				  IRQCHIP_AFFINITY_PRE_STARTUP,
 };
 
 static inline void init_IO_APIC_traps(void)
diff --git a/arch/x86/kernel/apic/msi.c b/arch/x86/kernel/apic/msi.c
index 44ebe25e7703..dbacb9ec8843 100644
--- a/arch/x86/kernel/apic/msi.c
+++ b/arch/x86/kernel/apic/msi.c
@@ -58,11 +58,13 @@ msi_set_affinity(struct irq_data *irqd, const struct cpumask *mask, bool force)
 	 *   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 interrupt is not yet started 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 ||
+	    !irqd_is_started(irqd) ||
 	    cfg->dest_apicid == old_cfg.dest_apicid) {
 		irq_msi_update_msg(irqd, cfg);
 		return ret;
@@ -150,7 +152,8 @@ static struct irq_chip pci_msi_controller = {
 	.irq_ack		= irq_chip_ack_parent,
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_set_affinity	= msi_set_affinity,
-	.flags			= IRQCHIP_SKIP_SET_WAKE,
+	.flags			= IRQCHIP_SKIP_SET_WAKE |
+				  IRQCHIP_AFFINITY_PRE_STARTUP,
 };
 
 int pci_msi_prepare(struct irq_domain *domain, struct device *dev, int nvec,
@@ -219,7 +222,8 @@ static struct irq_chip pci_msi_ir_controller = {
 	.irq_mask		= pci_msi_mask_irq,
 	.irq_ack		= irq_chip_ack_parent,
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
-	.flags			= IRQCHIP_SKIP_SET_WAKE,
+	.flags			= IRQCHIP_SKIP_SET_WAKE |
+				  IRQCHIP_AFFINITY_PRE_STARTUP,
 };
 
 static struct msi_domain_info pci_msi_ir_domain_info = {
@@ -273,7 +277,8 @@ static struct irq_chip dmar_msi_controller = {
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_compose_msi_msg	= dmar_msi_compose_msg,
 	.irq_write_msi_msg	= dmar_msi_write_msg,
-	.flags			= IRQCHIP_SKIP_SET_WAKE,
+	.flags			= IRQCHIP_SKIP_SET_WAKE |
+				  IRQCHIP_AFFINITY_PRE_STARTUP,
 };
 
 static int dmar_msi_init(struct irq_domain *domain,
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index 08651a4e6aa0..42fc41dd0e1f 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -508,7 +508,7 @@ static struct irq_chip hpet_msi_controller __ro_after_init = {
 	.irq_set_affinity = msi_domain_set_affinity,
 	.irq_retrigger = irq_chip_retrigger_hierarchy,
 	.irq_write_msi_msg = hpet_msi_write_msg,
-	.flags = IRQCHIP_SKIP_SET_WAKE,
+	.flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_AFFINITY_PRE_STARTUP,
 };
 
 static int hpet_msi_init(struct irq_domain *domain,