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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/x86/kernel/apic/vector.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'arch/x86/kernel/apic/vector.c')
-rw-r--r--arch/x86/kernel/apic/vector.c1336
1 files changed, 1336 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
new file mode 100644
index 000000000..c1efebd27
--- /dev/null
+++ b/arch/x86/kernel/apic/vector.c
@@ -0,0 +1,1336 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Local APIC related interfaces to support IOAPIC, MSI, etc.
+ *
+ * Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
+ * Moved from arch/x86/kernel/apic/io_apic.c.
+ * Jiang Liu <jiang.liu@linux.intel.com>
+ * Enable support of hierarchical irqdomains
+ */
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/compiler.h>
+#include <linux/slab.h>
+#include <asm/irqdomain.h>
+#include <asm/hw_irq.h>
+#include <asm/traps.h>
+#include <asm/apic.h>
+#include <asm/i8259.h>
+#include <asm/desc.h>
+#include <asm/irq_remapping.h>
+
+#include <asm/trace/irq_vectors.h>
+
+struct apic_chip_data {
+ struct irq_cfg hw_irq_cfg;
+ unsigned int vector;
+ unsigned int prev_vector;
+ unsigned int cpu;
+ unsigned int prev_cpu;
+ unsigned int irq;
+ struct hlist_node clist;
+ unsigned int move_in_progress : 1,
+ is_managed : 1,
+ can_reserve : 1,
+ has_reserved : 1;
+};
+
+struct irq_domain *x86_vector_domain;
+EXPORT_SYMBOL_GPL(x86_vector_domain);
+static DEFINE_RAW_SPINLOCK(vector_lock);
+static cpumask_var_t vector_searchmask;
+static struct irq_chip lapic_controller;
+static struct irq_matrix *vector_matrix;
+#ifdef CONFIG_SMP
+static DEFINE_PER_CPU(struct hlist_head, cleanup_list);
+#endif
+
+void lock_vector_lock(void)
+{
+ /* Used to the online set of cpus does not change
+ * during assign_irq_vector.
+ */
+ raw_spin_lock(&vector_lock);
+}
+
+void unlock_vector_lock(void)
+{
+ raw_spin_unlock(&vector_lock);
+}
+
+void init_irq_alloc_info(struct irq_alloc_info *info,
+ const struct cpumask *mask)
+{
+ memset(info, 0, sizeof(*info));
+ info->mask = mask;
+}
+
+void copy_irq_alloc_info(struct irq_alloc_info *dst, struct irq_alloc_info *src)
+{
+ if (src)
+ *dst = *src;
+ else
+ memset(dst, 0, sizeof(*dst));
+}
+
+static struct apic_chip_data *apic_chip_data(struct irq_data *irqd)
+{
+ if (!irqd)
+ return NULL;
+
+ while (irqd->parent_data)
+ irqd = irqd->parent_data;
+
+ return irqd->chip_data;
+}
+
+struct irq_cfg *irqd_cfg(struct irq_data *irqd)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+
+ return apicd ? &apicd->hw_irq_cfg : NULL;
+}
+EXPORT_SYMBOL_GPL(irqd_cfg);
+
+struct irq_cfg *irq_cfg(unsigned int irq)
+{
+ return irqd_cfg(irq_get_irq_data(irq));
+}
+
+static struct apic_chip_data *alloc_apic_chip_data(int node)
+{
+ struct apic_chip_data *apicd;
+
+ apicd = kzalloc_node(sizeof(*apicd), GFP_KERNEL, node);
+ if (apicd)
+ INIT_HLIST_NODE(&apicd->clist);
+ return apicd;
+}
+
+static void free_apic_chip_data(struct apic_chip_data *apicd)
+{
+ kfree(apicd);
+}
+
+static void apic_update_irq_cfg(struct irq_data *irqd, unsigned int vector,
+ unsigned int cpu)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+
+ lockdep_assert_held(&vector_lock);
+
+ apicd->hw_irq_cfg.vector = vector;
+ apicd->hw_irq_cfg.dest_apicid = apic->calc_dest_apicid(cpu);
+ irq_data_update_effective_affinity(irqd, cpumask_of(cpu));
+ trace_vector_config(irqd->irq, vector, cpu,
+ apicd->hw_irq_cfg.dest_apicid);
+}
+
+static void apic_update_vector(struct irq_data *irqd, unsigned int newvec,
+ unsigned int newcpu)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ struct irq_desc *desc = irq_data_to_desc(irqd);
+ bool managed = irqd_affinity_is_managed(irqd);
+
+ lockdep_assert_held(&vector_lock);
+
+ trace_vector_update(irqd->irq, newvec, newcpu, apicd->vector,
+ apicd->cpu);
+
+ /*
+ * If there is no vector associated or if the associated vector is
+ * the shutdown vector, which is associated to make PCI/MSI
+ * shutdown mode work, then there is nothing to release. Clear out
+ * prev_vector for this and the offlined target case.
+ */
+ apicd->prev_vector = 0;
+ if (!apicd->vector || apicd->vector == MANAGED_IRQ_SHUTDOWN_VECTOR)
+ goto setnew;
+ /*
+ * If the target CPU of the previous vector is online, then mark
+ * the vector as move in progress and store it for cleanup when the
+ * first interrupt on the new vector arrives. If the target CPU is
+ * offline then the regular release mechanism via the cleanup
+ * vector is not possible and the vector can be immediately freed
+ * in the underlying matrix allocator.
+ */
+ if (cpu_online(apicd->cpu)) {
+ apicd->move_in_progress = true;
+ apicd->prev_vector = apicd->vector;
+ apicd->prev_cpu = apicd->cpu;
+ WARN_ON_ONCE(apicd->cpu == newcpu);
+ } else {
+ irq_matrix_free(vector_matrix, apicd->cpu, apicd->vector,
+ managed);
+ }
+
+setnew:
+ apicd->vector = newvec;
+ apicd->cpu = newcpu;
+ BUG_ON(!IS_ERR_OR_NULL(per_cpu(vector_irq, newcpu)[newvec]));
+ per_cpu(vector_irq, newcpu)[newvec] = desc;
+}
+
+static void vector_assign_managed_shutdown(struct irq_data *irqd)
+{
+ unsigned int cpu = cpumask_first(cpu_online_mask);
+
+ apic_update_irq_cfg(irqd, MANAGED_IRQ_SHUTDOWN_VECTOR, cpu);
+}
+
+static int reserve_managed_vector(struct irq_data *irqd)
+{
+ const struct cpumask *affmsk = irq_data_get_affinity_mask(irqd);
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ unsigned long flags;
+ int ret;
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ apicd->is_managed = true;
+ ret = irq_matrix_reserve_managed(vector_matrix, affmsk);
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+ trace_vector_reserve_managed(irqd->irq, ret);
+ return ret;
+}
+
+static void reserve_irq_vector_locked(struct irq_data *irqd)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+
+ irq_matrix_reserve(vector_matrix);
+ apicd->can_reserve = true;
+ apicd->has_reserved = true;
+ irqd_set_can_reserve(irqd);
+ trace_vector_reserve(irqd->irq, 0);
+ vector_assign_managed_shutdown(irqd);
+}
+
+static int reserve_irq_vector(struct irq_data *irqd)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ reserve_irq_vector_locked(irqd);
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+ return 0;
+}
+
+static int
+assign_vector_locked(struct irq_data *irqd, const struct cpumask *dest)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ bool resvd = apicd->has_reserved;
+ unsigned int cpu = apicd->cpu;
+ int vector = apicd->vector;
+
+ lockdep_assert_held(&vector_lock);
+
+ /*
+ * If the current target CPU is online and in the new requested
+ * affinity mask, there is no point in moving the interrupt from
+ * one CPU to another.
+ */
+ if (vector && cpu_online(cpu) && cpumask_test_cpu(cpu, dest))
+ return 0;
+
+ /*
+ * Careful here. @apicd might either have move_in_progress set or
+ * be enqueued for cleanup. Assigning a new vector would either
+ * leave a stale vector on some CPU around or in case of a pending
+ * cleanup corrupt the hlist.
+ */
+ if (apicd->move_in_progress || !hlist_unhashed(&apicd->clist))
+ return -EBUSY;
+
+ vector = irq_matrix_alloc(vector_matrix, dest, resvd, &cpu);
+ trace_vector_alloc(irqd->irq, vector, resvd, vector);
+ if (vector < 0)
+ return vector;
+ apic_update_vector(irqd, vector, cpu);
+ apic_update_irq_cfg(irqd, vector, cpu);
+
+ return 0;
+}
+
+static int assign_irq_vector(struct irq_data *irqd, const struct cpumask *dest)
+{
+ unsigned long flags;
+ int ret;
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ cpumask_and(vector_searchmask, dest, cpu_online_mask);
+ ret = assign_vector_locked(irqd, vector_searchmask);
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+ return ret;
+}
+
+static int assign_irq_vector_any_locked(struct irq_data *irqd)
+{
+ /* Get the affinity mask - either irq_default_affinity or (user) set */
+ const struct cpumask *affmsk = irq_data_get_affinity_mask(irqd);
+ int node = irq_data_get_node(irqd);
+
+ if (node != NUMA_NO_NODE) {
+ /* Try the intersection of @affmsk and node mask */
+ cpumask_and(vector_searchmask, cpumask_of_node(node), affmsk);
+ if (!assign_vector_locked(irqd, vector_searchmask))
+ return 0;
+ }
+
+ /* Try the full affinity mask */
+ cpumask_and(vector_searchmask, affmsk, cpu_online_mask);
+ if (!assign_vector_locked(irqd, vector_searchmask))
+ return 0;
+
+ if (node != NUMA_NO_NODE) {
+ /* Try the node mask */
+ if (!assign_vector_locked(irqd, cpumask_of_node(node)))
+ return 0;
+ }
+
+ /* Try the full online mask */
+ return assign_vector_locked(irqd, cpu_online_mask);
+}
+
+static int
+assign_irq_vector_policy(struct irq_data *irqd, struct irq_alloc_info *info)
+{
+ if (irqd_affinity_is_managed(irqd))
+ return reserve_managed_vector(irqd);
+ if (info->mask)
+ return assign_irq_vector(irqd, info->mask);
+ /*
+ * Make only a global reservation with no guarantee. A real vector
+ * is associated at activation time.
+ */
+ return reserve_irq_vector(irqd);
+}
+
+static int
+assign_managed_vector(struct irq_data *irqd, const struct cpumask *dest)
+{
+ const struct cpumask *affmsk = irq_data_get_affinity_mask(irqd);
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ int vector, cpu;
+
+ cpumask_and(vector_searchmask, dest, affmsk);
+
+ /* set_affinity might call here for nothing */
+ if (apicd->vector && cpumask_test_cpu(apicd->cpu, vector_searchmask))
+ return 0;
+ vector = irq_matrix_alloc_managed(vector_matrix, vector_searchmask,
+ &cpu);
+ trace_vector_alloc_managed(irqd->irq, vector, vector);
+ if (vector < 0)
+ return vector;
+ apic_update_vector(irqd, vector, cpu);
+ apic_update_irq_cfg(irqd, vector, cpu);
+ return 0;
+}
+
+static void clear_irq_vector(struct irq_data *irqd)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ bool managed = irqd_affinity_is_managed(irqd);
+ unsigned int vector = apicd->vector;
+
+ lockdep_assert_held(&vector_lock);
+
+ if (!vector)
+ return;
+
+ trace_vector_clear(irqd->irq, vector, apicd->cpu, apicd->prev_vector,
+ apicd->prev_cpu);
+
+ per_cpu(vector_irq, apicd->cpu)[vector] = VECTOR_SHUTDOWN;
+ irq_matrix_free(vector_matrix, apicd->cpu, vector, managed);
+ apicd->vector = 0;
+
+ /* Clean up move in progress */
+ vector = apicd->prev_vector;
+ if (!vector)
+ return;
+
+ per_cpu(vector_irq, apicd->prev_cpu)[vector] = VECTOR_SHUTDOWN;
+ irq_matrix_free(vector_matrix, apicd->prev_cpu, vector, managed);
+ apicd->prev_vector = 0;
+ apicd->move_in_progress = 0;
+ hlist_del_init(&apicd->clist);
+}
+
+static void x86_vector_deactivate(struct irq_domain *dom, struct irq_data *irqd)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ unsigned long flags;
+
+ trace_vector_deactivate(irqd->irq, apicd->is_managed,
+ apicd->can_reserve, false);
+
+ /* Regular fixed assigned interrupt */
+ if (!apicd->is_managed && !apicd->can_reserve)
+ return;
+ /* If the interrupt has a global reservation, nothing to do */
+ if (apicd->has_reserved)
+ return;
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ clear_irq_vector(irqd);
+ if (apicd->can_reserve)
+ reserve_irq_vector_locked(irqd);
+ else
+ vector_assign_managed_shutdown(irqd);
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+}
+
+static int activate_reserved(struct irq_data *irqd)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ int ret;
+
+ ret = assign_irq_vector_any_locked(irqd);
+ if (!ret) {
+ apicd->has_reserved = false;
+ /*
+ * Core might have disabled reservation mode after
+ * allocating the irq descriptor. Ideally this should
+ * happen before allocation time, but that would require
+ * completely convoluted ways of transporting that
+ * information.
+ */
+ if (!irqd_can_reserve(irqd))
+ apicd->can_reserve = false;
+ }
+
+ /*
+ * Check to ensure that the effective affinity mask is a subset
+ * the user supplied affinity mask, and warn the user if it is not
+ */
+ if (!cpumask_subset(irq_data_get_effective_affinity_mask(irqd),
+ irq_data_get_affinity_mask(irqd))) {
+ pr_warn("irq %u: Affinity broken due to vector space exhaustion.\n",
+ irqd->irq);
+ }
+
+ return ret;
+}
+
+static int activate_managed(struct irq_data *irqd)
+{
+ const struct cpumask *dest = irq_data_get_affinity_mask(irqd);
+ int ret;
+
+ cpumask_and(vector_searchmask, dest, cpu_online_mask);
+ if (WARN_ON_ONCE(cpumask_empty(vector_searchmask))) {
+ /* Something in the core code broke! Survive gracefully */
+ pr_err("Managed startup for irq %u, but no CPU\n", irqd->irq);
+ return -EINVAL;
+ }
+
+ ret = assign_managed_vector(irqd, vector_searchmask);
+ /*
+ * This should not happen. The vector reservation got buggered. Handle
+ * it gracefully.
+ */
+ if (WARN_ON_ONCE(ret < 0)) {
+ pr_err("Managed startup irq %u, no vector available\n",
+ irqd->irq);
+ }
+ return ret;
+}
+
+static int x86_vector_activate(struct irq_domain *dom, struct irq_data *irqd,
+ bool reserve)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ unsigned long flags;
+ int ret = 0;
+
+ trace_vector_activate(irqd->irq, apicd->is_managed,
+ apicd->can_reserve, reserve);
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ if (!apicd->can_reserve && !apicd->is_managed)
+ assign_irq_vector_any_locked(irqd);
+ else if (reserve || irqd_is_managed_and_shutdown(irqd))
+ vector_assign_managed_shutdown(irqd);
+ else if (apicd->is_managed)
+ ret = activate_managed(irqd);
+ else if (apicd->has_reserved)
+ ret = activate_reserved(irqd);
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+ return ret;
+}
+
+static void vector_free_reserved_and_managed(struct irq_data *irqd)
+{
+ const struct cpumask *dest = irq_data_get_affinity_mask(irqd);
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+
+ trace_vector_teardown(irqd->irq, apicd->is_managed,
+ apicd->has_reserved);
+
+ if (apicd->has_reserved)
+ irq_matrix_remove_reserved(vector_matrix);
+ if (apicd->is_managed)
+ irq_matrix_remove_managed(vector_matrix, dest);
+}
+
+static void x86_vector_free_irqs(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs)
+{
+ struct apic_chip_data *apicd;
+ struct irq_data *irqd;
+ unsigned long flags;
+ int i;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irqd = irq_domain_get_irq_data(x86_vector_domain, virq + i);
+ if (irqd && irqd->chip_data) {
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ clear_irq_vector(irqd);
+ vector_free_reserved_and_managed(irqd);
+ apicd = irqd->chip_data;
+ irq_domain_reset_irq_data(irqd);
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+ free_apic_chip_data(apicd);
+ }
+ }
+}
+
+static bool vector_configure_legacy(unsigned int virq, struct irq_data *irqd,
+ struct apic_chip_data *apicd)
+{
+ unsigned long flags;
+ bool realloc = false;
+
+ apicd->vector = ISA_IRQ_VECTOR(virq);
+ apicd->cpu = 0;
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ /*
+ * If the interrupt is activated, then it must stay at this vector
+ * position. That's usually the timer interrupt (0).
+ */
+ if (irqd_is_activated(irqd)) {
+ trace_vector_setup(virq, true, 0);
+ apic_update_irq_cfg(irqd, apicd->vector, apicd->cpu);
+ } else {
+ /* Release the vector */
+ apicd->can_reserve = true;
+ irqd_set_can_reserve(irqd);
+ clear_irq_vector(irqd);
+ realloc = true;
+ }
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+ return realloc;
+}
+
+static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct irq_alloc_info *info = arg;
+ struct apic_chip_data *apicd;
+ struct irq_data *irqd;
+ int i, err, node;
+
+ if (disable_apic)
+ return -ENXIO;
+
+ /*
+ * Catch any attempt to touch the cascade interrupt on a PIC
+ * equipped system.
+ */
+ if (WARN_ON_ONCE(info->flags & X86_IRQ_ALLOC_LEGACY &&
+ virq == PIC_CASCADE_IR))
+ return -EINVAL;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irqd = irq_domain_get_irq_data(domain, virq + i);
+ BUG_ON(!irqd);
+ node = irq_data_get_node(irqd);
+ WARN_ON_ONCE(irqd->chip_data);
+ apicd = alloc_apic_chip_data(node);
+ if (!apicd) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ apicd->irq = virq + i;
+ irqd->chip = &lapic_controller;
+ irqd->chip_data = apicd;
+ irqd->hwirq = virq + i;
+ irqd_set_single_target(irqd);
+ /*
+ * Prevent that any of these interrupts is invoked in
+ * non interrupt context via e.g. generic_handle_irq()
+ * as that can corrupt the affinity move state.
+ */
+ irqd_set_handle_enforce_irqctx(irqd);
+
+ /* Don't invoke affinity setter on deactivated interrupts */
+ irqd_set_affinity_on_activate(irqd);
+
+ /*
+ * Legacy vectors are already assigned when the IOAPIC
+ * takes them over. They stay on the same vector. This is
+ * required for check_timer() to work correctly as it might
+ * switch back to legacy mode. Only update the hardware
+ * config.
+ */
+ if (info->flags & X86_IRQ_ALLOC_LEGACY) {
+ if (!vector_configure_legacy(virq + i, irqd, apicd))
+ continue;
+ }
+
+ err = assign_irq_vector_policy(irqd, info);
+ trace_vector_setup(virq + i, false, err);
+ if (err) {
+ irqd->chip_data = NULL;
+ free_apic_chip_data(apicd);
+ goto error;
+ }
+ }
+
+ return 0;
+
+error:
+ x86_vector_free_irqs(domain, virq, i);
+ return err;
+}
+
+#ifdef CONFIG_GENERIC_IRQ_DEBUGFS
+static void x86_vector_debug_show(struct seq_file *m, struct irq_domain *d,
+ struct irq_data *irqd, int ind)
+{
+ struct apic_chip_data apicd;
+ unsigned long flags;
+ int irq;
+
+ if (!irqd) {
+ irq_matrix_debug_show(m, vector_matrix, ind);
+ return;
+ }
+
+ irq = irqd->irq;
+ if (irq < nr_legacy_irqs() && !test_bit(irq, &io_apic_irqs)) {
+ seq_printf(m, "%*sVector: %5d\n", ind, "", ISA_IRQ_VECTOR(irq));
+ seq_printf(m, "%*sTarget: Legacy PIC all CPUs\n", ind, "");
+ return;
+ }
+
+ if (!irqd->chip_data) {
+ seq_printf(m, "%*sVector: Not assigned\n", ind, "");
+ return;
+ }
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ memcpy(&apicd, irqd->chip_data, sizeof(apicd));
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+
+ seq_printf(m, "%*sVector: %5u\n", ind, "", apicd.vector);
+ seq_printf(m, "%*sTarget: %5u\n", ind, "", apicd.cpu);
+ if (apicd.prev_vector) {
+ seq_printf(m, "%*sPrevious vector: %5u\n", ind, "", apicd.prev_vector);
+ seq_printf(m, "%*sPrevious target: %5u\n", ind, "", apicd.prev_cpu);
+ }
+ seq_printf(m, "%*smove_in_progress: %u\n", ind, "", apicd.move_in_progress ? 1 : 0);
+ seq_printf(m, "%*sis_managed: %u\n", ind, "", apicd.is_managed ? 1 : 0);
+ seq_printf(m, "%*scan_reserve: %u\n", ind, "", apicd.can_reserve ? 1 : 0);
+ seq_printf(m, "%*shas_reserved: %u\n", ind, "", apicd.has_reserved ? 1 : 0);
+ seq_printf(m, "%*scleanup_pending: %u\n", ind, "", !hlist_unhashed(&apicd.clist));
+}
+#endif
+
+int x86_fwspec_is_ioapic(struct irq_fwspec *fwspec)
+{
+ if (fwspec->param_count != 1)
+ return 0;
+
+ if (is_fwnode_irqchip(fwspec->fwnode)) {
+ const char *fwname = fwnode_get_name(fwspec->fwnode);
+ return fwname && !strncmp(fwname, "IO-APIC-", 8) &&
+ simple_strtol(fwname+8, NULL, 10) == fwspec->param[0];
+ }
+ return to_of_node(fwspec->fwnode) &&
+ of_device_is_compatible(to_of_node(fwspec->fwnode),
+ "intel,ce4100-ioapic");
+}
+
+int x86_fwspec_is_hpet(struct irq_fwspec *fwspec)
+{
+ if (fwspec->param_count != 1)
+ return 0;
+
+ if (is_fwnode_irqchip(fwspec->fwnode)) {
+ const char *fwname = fwnode_get_name(fwspec->fwnode);
+ return fwname && !strncmp(fwname, "HPET-MSI-", 9) &&
+ simple_strtol(fwname+9, NULL, 10) == fwspec->param[0];
+ }
+ return 0;
+}
+
+static int x86_vector_select(struct irq_domain *d, struct irq_fwspec *fwspec,
+ enum irq_domain_bus_token bus_token)
+{
+ /*
+ * HPET and I/OAPIC cannot be parented in the vector domain
+ * if IRQ remapping is enabled. APIC IDs above 15 bits are
+ * only permitted if IRQ remapping is enabled, so check that.
+ */
+ if (apic->apic_id_valid(32768))
+ return 0;
+
+ return x86_fwspec_is_ioapic(fwspec) || x86_fwspec_is_hpet(fwspec);
+}
+
+static const struct irq_domain_ops x86_vector_domain_ops = {
+ .select = x86_vector_select,
+ .alloc = x86_vector_alloc_irqs,
+ .free = x86_vector_free_irqs,
+ .activate = x86_vector_activate,
+ .deactivate = x86_vector_deactivate,
+#ifdef CONFIG_GENERIC_IRQ_DEBUGFS
+ .debug_show = x86_vector_debug_show,
+#endif
+};
+
+int __init arch_probe_nr_irqs(void)
+{
+ int nr;
+
+ if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
+ nr_irqs = NR_VECTORS * nr_cpu_ids;
+
+ nr = (gsi_top + nr_legacy_irqs()) + 8 * nr_cpu_ids;
+#if defined(CONFIG_PCI_MSI)
+ /*
+ * for MSI and HT dyn irq
+ */
+ if (gsi_top <= NR_IRQS_LEGACY)
+ nr += 8 * nr_cpu_ids;
+ else
+ nr += gsi_top * 16;
+#endif
+ if (nr < nr_irqs)
+ nr_irqs = nr;
+
+ /*
+ * We don't know if PIC is present at this point so we need to do
+ * probe() to get the right number of legacy IRQs.
+ */
+ return legacy_pic->probe();
+}
+
+void lapic_assign_legacy_vector(unsigned int irq, bool replace)
+{
+ /*
+ * Use assign system here so it wont get accounted as allocated
+ * and moveable in the cpu hotplug check and it prevents managed
+ * irq reservation from touching it.
+ */
+ irq_matrix_assign_system(vector_matrix, ISA_IRQ_VECTOR(irq), replace);
+}
+
+void __init lapic_update_legacy_vectors(void)
+{
+ unsigned int i;
+
+ if (IS_ENABLED(CONFIG_X86_IO_APIC) && nr_ioapics > 0)
+ return;
+
+ /*
+ * If the IO/APIC is disabled via config, kernel command line or
+ * lack of enumeration then all legacy interrupts are routed
+ * through the PIC. Make sure that they are marked as legacy
+ * vectors. PIC_CASCADE_IRQ has already been marked in
+ * lapic_assign_system_vectors().
+ */
+ for (i = 0; i < nr_legacy_irqs(); i++) {
+ if (i != PIC_CASCADE_IR)
+ lapic_assign_legacy_vector(i, true);
+ }
+}
+
+void __init lapic_assign_system_vectors(void)
+{
+ unsigned int i, vector;
+
+ for_each_set_bit(vector, system_vectors, NR_VECTORS)
+ irq_matrix_assign_system(vector_matrix, vector, false);
+
+ if (nr_legacy_irqs() > 1)
+ lapic_assign_legacy_vector(PIC_CASCADE_IR, false);
+
+ /* System vectors are reserved, online it */
+ irq_matrix_online(vector_matrix);
+
+ /* Mark the preallocated legacy interrupts */
+ for (i = 0; i < nr_legacy_irqs(); i++) {
+ /*
+ * Don't touch the cascade interrupt. It's unusable
+ * on PIC equipped machines. See the large comment
+ * in the IO/APIC code.
+ */
+ if (i != PIC_CASCADE_IR)
+ irq_matrix_assign(vector_matrix, ISA_IRQ_VECTOR(i));
+ }
+}
+
+int __init arch_early_irq_init(void)
+{
+ struct fwnode_handle *fn;
+
+ fn = irq_domain_alloc_named_fwnode("VECTOR");
+ BUG_ON(!fn);
+ x86_vector_domain = irq_domain_create_tree(fn, &x86_vector_domain_ops,
+ NULL);
+ BUG_ON(x86_vector_domain == NULL);
+ irq_set_default_host(x86_vector_domain);
+
+ BUG_ON(!alloc_cpumask_var(&vector_searchmask, GFP_KERNEL));
+
+ /*
+ * Allocate the vector matrix allocator data structure and limit the
+ * search area.
+ */
+ vector_matrix = irq_alloc_matrix(NR_VECTORS, FIRST_EXTERNAL_VECTOR,
+ FIRST_SYSTEM_VECTOR);
+ BUG_ON(!vector_matrix);
+
+ return arch_early_ioapic_init();
+}
+
+#ifdef CONFIG_SMP
+
+static struct irq_desc *__setup_vector_irq(int vector)
+{
+ int isairq = vector - ISA_IRQ_VECTOR(0);
+
+ /* Check whether the irq is in the legacy space */
+ if (isairq < 0 || isairq >= nr_legacy_irqs())
+ return VECTOR_UNUSED;
+ /* Check whether the irq is handled by the IOAPIC */
+ if (test_bit(isairq, &io_apic_irqs))
+ return VECTOR_UNUSED;
+ return irq_to_desc(isairq);
+}
+
+/* Online the local APIC infrastructure and initialize the vectors */
+void lapic_online(void)
+{
+ unsigned int vector;
+
+ lockdep_assert_held(&vector_lock);
+
+ /* Online the vector matrix array for this CPU */
+ irq_matrix_online(vector_matrix);
+
+ /*
+ * The interrupt affinity logic never targets interrupts to offline
+ * CPUs. The exception are the legacy PIC interrupts. In general
+ * they are only targeted to CPU0, but depending on the platform
+ * they can be distributed to any online CPU in hardware. The
+ * kernel has no influence on that. So all active legacy vectors
+ * must be installed on all CPUs. All non legacy interrupts can be
+ * cleared.
+ */
+ for (vector = 0; vector < NR_VECTORS; vector++)
+ this_cpu_write(vector_irq[vector], __setup_vector_irq(vector));
+}
+
+void lapic_offline(void)
+{
+ lock_vector_lock();
+ irq_matrix_offline(vector_matrix);
+ unlock_vector_lock();
+}
+
+static int apic_set_affinity(struct irq_data *irqd,
+ const struct cpumask *dest, bool force)
+{
+ int err;
+
+ if (WARN_ON_ONCE(!irqd_is_activated(irqd)))
+ return -EIO;
+
+ raw_spin_lock(&vector_lock);
+ cpumask_and(vector_searchmask, dest, cpu_online_mask);
+ if (irqd_affinity_is_managed(irqd))
+ err = assign_managed_vector(irqd, vector_searchmask);
+ else
+ err = assign_vector_locked(irqd, vector_searchmask);
+ raw_spin_unlock(&vector_lock);
+ return err ? err : IRQ_SET_MASK_OK;
+}
+
+#else
+# define apic_set_affinity NULL
+#endif
+
+static int apic_retrigger_irq(struct irq_data *irqd)
+{
+ struct apic_chip_data *apicd = apic_chip_data(irqd);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&vector_lock, flags);
+ apic->send_IPI(apicd->cpu, apicd->vector);
+ raw_spin_unlock_irqrestore(&vector_lock, flags);
+
+ return 1;
+}
+
+void apic_ack_irq(struct irq_data *irqd)
+{
+ irq_move_irq(irqd);
+ ack_APIC_irq();
+}
+
+void apic_ack_edge(struct irq_data *irqd)
+{
+ irq_complete_move(irqd_cfg(irqd));
+ apic_ack_irq(irqd);
+}
+
+static void x86_vector_msi_compose_msg(struct irq_data *data,
+ struct msi_msg *msg)
+{
+ __irq_msi_compose_msg(irqd_cfg(data), msg, false);
+}
+
+static struct irq_chip lapic_controller = {
+ .name = "APIC",
+ .irq_ack = apic_ack_edge,
+ .irq_set_affinity = apic_set_affinity,
+ .irq_compose_msi_msg = x86_vector_msi_compose_msg,
+ .irq_retrigger = apic_retrigger_irq,
+};
+
+#ifdef CONFIG_SMP
+
+static void free_moved_vector(struct apic_chip_data *apicd)
+{
+ unsigned int vector = apicd->prev_vector;
+ unsigned int cpu = apicd->prev_cpu;
+ bool managed = apicd->is_managed;
+
+ /*
+ * Managed interrupts are usually not migrated away
+ * from an online CPU, but CPU isolation 'managed_irq'
+ * can make that happen.
+ * 1) Activation does not take the isolation into account
+ * to keep the code simple
+ * 2) Migration away from an isolated CPU can happen when
+ * a non-isolated CPU which is in the calculated
+ * affinity mask comes online.
+ */
+ trace_vector_free_moved(apicd->irq, cpu, vector, managed);
+ irq_matrix_free(vector_matrix, cpu, vector, managed);
+ per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
+ hlist_del_init(&apicd->clist);
+ apicd->prev_vector = 0;
+ apicd->move_in_progress = 0;
+}
+
+DEFINE_IDTENTRY_SYSVEC(sysvec_irq_move_cleanup)
+{
+ struct hlist_head *clhead = this_cpu_ptr(&cleanup_list);
+ struct apic_chip_data *apicd;
+ struct hlist_node *tmp;
+
+ ack_APIC_irq();
+ /* Prevent vectors vanishing under us */
+ raw_spin_lock(&vector_lock);
+
+ hlist_for_each_entry_safe(apicd, tmp, clhead, clist) {
+ unsigned int irr, vector = apicd->prev_vector;
+
+ /*
+ * Paranoia: Check if the vector that needs to be cleaned
+ * up is registered at the APICs IRR. If so, then this is
+ * not the best time to clean it up. Clean it up in the
+ * next attempt by sending another IRQ_MOVE_CLEANUP_VECTOR
+ * to this CPU. IRQ_MOVE_CLEANUP_VECTOR is the lowest
+ * priority external vector, so on return from this
+ * interrupt the device interrupt will happen first.
+ */
+ irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
+ if (irr & (1U << (vector % 32))) {
+ apic->send_IPI_self(IRQ_MOVE_CLEANUP_VECTOR);
+ continue;
+ }
+ free_moved_vector(apicd);
+ }
+
+ raw_spin_unlock(&vector_lock);
+}
+
+static void __send_cleanup_vector(struct apic_chip_data *apicd)
+{
+ unsigned int cpu;
+
+ raw_spin_lock(&vector_lock);
+ apicd->move_in_progress = 0;
+ cpu = apicd->prev_cpu;
+ if (cpu_online(cpu)) {
+ hlist_add_head(&apicd->clist, per_cpu_ptr(&cleanup_list, cpu));
+ apic->send_IPI(cpu, IRQ_MOVE_CLEANUP_VECTOR);
+ } else {
+ apicd->prev_vector = 0;
+ }
+ raw_spin_unlock(&vector_lock);
+}
+
+void send_cleanup_vector(struct irq_cfg *cfg)
+{
+ struct apic_chip_data *apicd;
+
+ apicd = container_of(cfg, struct apic_chip_data, hw_irq_cfg);
+ if (apicd->move_in_progress)
+ __send_cleanup_vector(apicd);
+}
+
+void irq_complete_move(struct irq_cfg *cfg)
+{
+ struct apic_chip_data *apicd;
+
+ apicd = container_of(cfg, struct apic_chip_data, hw_irq_cfg);
+ if (likely(!apicd->move_in_progress))
+ return;
+
+ /*
+ * If the interrupt arrived on the new target CPU, cleanup the
+ * vector on the old target CPU. A vector check is not required
+ * because an interrupt can never move from one vector to another
+ * on the same CPU.
+ */
+ if (apicd->cpu == smp_processor_id())
+ __send_cleanup_vector(apicd);
+}
+
+/*
+ * Called from fixup_irqs() with @desc->lock held and interrupts disabled.
+ */
+void irq_force_complete_move(struct irq_desc *desc)
+{
+ struct apic_chip_data *apicd;
+ struct irq_data *irqd;
+ unsigned int vector;
+
+ /*
+ * The function is called for all descriptors regardless of which
+ * irqdomain they belong to. For example if an IRQ is provided by
+ * an irq_chip as part of a GPIO driver, the chip data for that
+ * descriptor is specific to the irq_chip in question.
+ *
+ * Check first that the chip_data is what we expect
+ * (apic_chip_data) before touching it any further.
+ */
+ irqd = irq_domain_get_irq_data(x86_vector_domain,
+ irq_desc_get_irq(desc));
+ if (!irqd)
+ return;
+
+ raw_spin_lock(&vector_lock);
+ apicd = apic_chip_data(irqd);
+ if (!apicd)
+ goto unlock;
+
+ /*
+ * If prev_vector is empty, no action required.
+ */
+ vector = apicd->prev_vector;
+ if (!vector)
+ goto unlock;
+
+ /*
+ * This is tricky. If the cleanup of the old vector has not been
+ * done yet, then the following setaffinity call will fail with
+ * -EBUSY. This can leave the interrupt in a stale state.
+ *
+ * All CPUs are stuck in stop machine with interrupts disabled so
+ * calling __irq_complete_move() would be completely pointless.
+ *
+ * 1) The interrupt is in move_in_progress state. That means that we
+ * have not seen an interrupt since the io_apic was reprogrammed to
+ * the new vector.
+ *
+ * 2) The interrupt has fired on the new vector, but the cleanup IPIs
+ * have not been processed yet.
+ */
+ if (apicd->move_in_progress) {
+ /*
+ * In theory there is a race:
+ *
+ * set_ioapic(new_vector) <-- Interrupt is raised before update
+ * is effective, i.e. it's raised on
+ * the old vector.
+ *
+ * So if the target cpu cannot handle that interrupt before
+ * the old vector is cleaned up, we get a spurious interrupt
+ * and in the worst case the ioapic irq line becomes stale.
+ *
+ * But in case of cpu hotplug this should be a non issue
+ * because if the affinity update happens right before all
+ * cpus rendezvous in stop machine, there is no way that the
+ * interrupt can be blocked on the target cpu because all cpus
+ * loops first with interrupts enabled in stop machine, so the
+ * old vector is not yet cleaned up when the interrupt fires.
+ *
+ * So the only way to run into this issue is if the delivery
+ * of the interrupt on the apic/system bus would be delayed
+ * beyond the point where the target cpu disables interrupts
+ * in stop machine. I doubt that it can happen, but at least
+ * there is a theoretical chance. Virtualization might be
+ * able to expose this, but AFAICT the IOAPIC emulation is not
+ * as stupid as the real hardware.
+ *
+ * Anyway, there is nothing we can do about that at this point
+ * w/o refactoring the whole fixup_irq() business completely.
+ * We print at least the irq number and the old vector number,
+ * so we have the necessary information when a problem in that
+ * area arises.
+ */
+ pr_warn("IRQ fixup: irq %d move in progress, old vector %d\n",
+ irqd->irq, vector);
+ }
+ free_moved_vector(apicd);
+unlock:
+ raw_spin_unlock(&vector_lock);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * Note, this is not accurate accounting, but at least good enough to
+ * prevent that the actual interrupt move will run out of vectors.
+ */
+int lapic_can_unplug_cpu(void)
+{
+ unsigned int rsvd, avl, tomove, cpu = smp_processor_id();
+ int ret = 0;
+
+ raw_spin_lock(&vector_lock);
+ tomove = irq_matrix_allocated(vector_matrix);
+ avl = irq_matrix_available(vector_matrix, true);
+ if (avl < tomove) {
+ pr_warn("CPU %u has %u vectors, %u available. Cannot disable CPU\n",
+ cpu, tomove, avl);
+ ret = -ENOSPC;
+ goto out;
+ }
+ rsvd = irq_matrix_reserved(vector_matrix);
+ if (avl < rsvd) {
+ pr_warn("Reserved vectors %u > available %u. IRQ request may fail\n",
+ rsvd, avl);
+ }
+out:
+ raw_spin_unlock(&vector_lock);
+ return ret;
+}
+#endif /* HOTPLUG_CPU */
+#endif /* SMP */
+
+static void __init print_APIC_field(int base)
+{
+ int i;
+
+ printk(KERN_DEBUG);
+
+ for (i = 0; i < 8; i++)
+ pr_cont("%08x", apic_read(base + i*0x10));
+
+ pr_cont("\n");
+}
+
+static void __init print_local_APIC(void *dummy)
+{
+ unsigned int i, v, ver, maxlvt;
+ u64 icr;
+
+ pr_debug("printing local APIC contents on CPU#%d/%d:\n",
+ smp_processor_id(), hard_smp_processor_id());
+ v = apic_read(APIC_ID);
+ pr_info("... APIC ID: %08x (%01x)\n", v, read_apic_id());
+ v = apic_read(APIC_LVR);
+ pr_info("... APIC VERSION: %08x\n", v);
+ ver = GET_APIC_VERSION(v);
+ maxlvt = lapic_get_maxlvt();
+
+ v = apic_read(APIC_TASKPRI);
+ pr_debug("... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
+
+ /* !82489DX */
+ if (APIC_INTEGRATED(ver)) {
+ if (!APIC_XAPIC(ver)) {
+ v = apic_read(APIC_ARBPRI);
+ pr_debug("... APIC ARBPRI: %08x (%02x)\n",
+ v, v & APIC_ARBPRI_MASK);
+ }
+ v = apic_read(APIC_PROCPRI);
+ pr_debug("... APIC PROCPRI: %08x\n", v);
+ }
+
+ /*
+ * Remote read supported only in the 82489DX and local APIC for
+ * Pentium processors.
+ */
+ if (!APIC_INTEGRATED(ver) || maxlvt == 3) {
+ v = apic_read(APIC_RRR);
+ pr_debug("... APIC RRR: %08x\n", v);
+ }
+
+ v = apic_read(APIC_LDR);
+ pr_debug("... APIC LDR: %08x\n", v);
+ if (!x2apic_enabled()) {
+ v = apic_read(APIC_DFR);
+ pr_debug("... APIC DFR: %08x\n", v);
+ }
+ v = apic_read(APIC_SPIV);
+ pr_debug("... APIC SPIV: %08x\n", v);
+
+ pr_debug("... APIC ISR field:\n");
+ print_APIC_field(APIC_ISR);
+ pr_debug("... APIC TMR field:\n");
+ print_APIC_field(APIC_TMR);
+ pr_debug("... APIC IRR field:\n");
+ print_APIC_field(APIC_IRR);
+
+ /* !82489DX */
+ if (APIC_INTEGRATED(ver)) {
+ /* Due to the Pentium erratum 3AP. */
+ if (maxlvt > 3)
+ apic_write(APIC_ESR, 0);
+
+ v = apic_read(APIC_ESR);
+ pr_debug("... APIC ESR: %08x\n", v);
+ }
+
+ icr = apic_icr_read();
+ pr_debug("... APIC ICR: %08x\n", (u32)icr);
+ pr_debug("... APIC ICR2: %08x\n", (u32)(icr >> 32));
+
+ v = apic_read(APIC_LVTT);
+ pr_debug("... APIC LVTT: %08x\n", v);
+
+ if (maxlvt > 3) {
+ /* PC is LVT#4. */
+ v = apic_read(APIC_LVTPC);
+ pr_debug("... APIC LVTPC: %08x\n", v);
+ }
+ v = apic_read(APIC_LVT0);
+ pr_debug("... APIC LVT0: %08x\n", v);
+ v = apic_read(APIC_LVT1);
+ pr_debug("... APIC LVT1: %08x\n", v);
+
+ if (maxlvt > 2) {
+ /* ERR is LVT#3. */
+ v = apic_read(APIC_LVTERR);
+ pr_debug("... APIC LVTERR: %08x\n", v);
+ }
+
+ v = apic_read(APIC_TMICT);
+ pr_debug("... APIC TMICT: %08x\n", v);
+ v = apic_read(APIC_TMCCT);
+ pr_debug("... APIC TMCCT: %08x\n", v);
+ v = apic_read(APIC_TDCR);
+ pr_debug("... APIC TDCR: %08x\n", v);
+
+ if (boot_cpu_has(X86_FEATURE_EXTAPIC)) {
+ v = apic_read(APIC_EFEAT);
+ maxlvt = (v >> 16) & 0xff;
+ pr_debug("... APIC EFEAT: %08x\n", v);
+ v = apic_read(APIC_ECTRL);
+ pr_debug("... APIC ECTRL: %08x\n", v);
+ for (i = 0; i < maxlvt; i++) {
+ v = apic_read(APIC_EILVTn(i));
+ pr_debug("... APIC EILVT%d: %08x\n", i, v);
+ }
+ }
+ pr_cont("\n");
+}
+
+static void __init print_local_APICs(int maxcpu)
+{
+ int cpu;
+
+ if (!maxcpu)
+ return;
+
+ preempt_disable();
+ for_each_online_cpu(cpu) {
+ if (cpu >= maxcpu)
+ break;
+ smp_call_function_single(cpu, print_local_APIC, NULL, 1);
+ }
+ preempt_enable();
+}
+
+static void __init print_PIC(void)
+{
+ unsigned int v;
+ unsigned long flags;
+
+ if (!nr_legacy_irqs())
+ return;
+
+ pr_debug("\nprinting PIC contents\n");
+
+ raw_spin_lock_irqsave(&i8259A_lock, flags);
+
+ v = inb(0xa1) << 8 | inb(0x21);
+ pr_debug("... PIC IMR: %04x\n", v);
+
+ v = inb(0xa0) << 8 | inb(0x20);
+ pr_debug("... PIC IRR: %04x\n", v);
+
+ outb(0x0b, 0xa0);
+ outb(0x0b, 0x20);
+ v = inb(0xa0) << 8 | inb(0x20);
+ outb(0x0a, 0xa0);
+ outb(0x0a, 0x20);
+
+ raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+
+ pr_debug("... PIC ISR: %04x\n", v);
+
+ v = inb(PIC_ELCR2) << 8 | inb(PIC_ELCR1);
+ pr_debug("... PIC ELCR: %04x\n", v);
+}
+
+static int show_lapic __initdata = 1;
+static __init int setup_show_lapic(char *arg)
+{
+ int num = -1;
+
+ if (strcmp(arg, "all") == 0) {
+ show_lapic = CONFIG_NR_CPUS;
+ } else {
+ get_option(&arg, &num);
+ if (num >= 0)
+ show_lapic = num;
+ }
+
+ return 1;
+}
+__setup("show_lapic=", setup_show_lapic);
+
+static int __init print_ICs(void)
+{
+ if (apic_verbosity == APIC_QUIET)
+ return 0;
+
+ print_PIC();
+
+ /* don't print out if apic is not there */
+ if (!boot_cpu_has(X86_FEATURE_APIC) && !apic_from_smp_config())
+ return 0;
+
+ print_local_APICs(show_lapic);
+ print_IO_APICs();
+
+ return 0;
+}
+
+late_initcall(print_ICs);