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().
  ...

1 files changed, 853 insertions, 0 deletions

diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
new file mode 100644
index 000000000..cfb5fe9a5
--- /dev/null
+++ b/drivers/iommu/iommufd/selftest.c
@@ -0,0 +1,853 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES.
+ *
+ * Kernel side components to support tools/testing/selftests/iommu
+ */
+#include <linux/slab.h>
+#include <linux/iommu.h>
+#include <linux/xarray.h>
+#include <linux/file.h>
+#include <linux/anon_inodes.h>
+#include <linux/fault-inject.h>
+#include <uapi/linux/iommufd.h>
+
+#include "io_pagetable.h"
+#include "iommufd_private.h"
+#include "iommufd_test.h"
+
+static DECLARE_FAULT_ATTR(fail_iommufd);
+static struct dentry *dbgfs_root;
+
+size_t iommufd_test_memory_limit = 65536;
+
+enum {
+	MOCK_IO_PAGE_SIZE = PAGE_SIZE / 2,
+
+	/*
+	 * Like a real page table alignment requires the low bits of the address
+	 * to be zero. xarray also requires the high bit to be zero, so we store
+	 * the pfns shifted. The upper bits are used for metadata.
+	 */
+	MOCK_PFN_MASK = ULONG_MAX / MOCK_IO_PAGE_SIZE,
+
+	_MOCK_PFN_START = MOCK_PFN_MASK + 1,
+	MOCK_PFN_START_IOVA = _MOCK_PFN_START,
+	MOCK_PFN_LAST_IOVA = _MOCK_PFN_START,
+};
+
+/*
+ * Syzkaller has trouble randomizing the correct iova to use since it is linked
+ * to the map ioctl's output, and it has no ide about that. So, simplify things.
+ * In syzkaller mode the 64 bit IOVA is converted into an nth area and offset
+ * value. This has a much smaller randomization space and syzkaller can hit it.
+ */
+static unsigned long iommufd_test_syz_conv_iova(struct io_pagetable *iopt,
+						u64 *iova)
+{
+	struct syz_layout {
+		__u32 nth_area;
+		__u32 offset;
+	};
+	struct syz_layout *syz = (void *)iova;
+	unsigned int nth = syz->nth_area;
+	struct iopt_area *area;
+
+	down_read(&iopt->iova_rwsem);
+	for (area = iopt_area_iter_first(iopt, 0, ULONG_MAX); area;
+	     area = iopt_area_iter_next(area, 0, ULONG_MAX)) {
+		if (nth == 0) {
+			up_read(&iopt->iova_rwsem);
+			return iopt_area_iova(area) + syz->offset;
+		}
+		nth--;
+	}
+	up_read(&iopt->iova_rwsem);
+
+	return 0;
+}
+
+void iommufd_test_syz_conv_iova_id(struct iommufd_ucmd *ucmd,
+				   unsigned int ioas_id, u64 *iova, u32 *flags)
+{
+	struct iommufd_ioas *ioas;
+
+	if (!(*flags & MOCK_FLAGS_ACCESS_SYZ))
+		return;
+	*flags &= ~(u32)MOCK_FLAGS_ACCESS_SYZ;
+
+	ioas = iommufd_get_ioas(ucmd, ioas_id);
+	if (IS_ERR(ioas))
+		return;
+	*iova = iommufd_test_syz_conv_iova(&ioas->iopt, iova);
+	iommufd_put_object(&ioas->obj);
+}
+
+struct mock_iommu_domain {
+	struct iommu_domain domain;
+	struct xarray pfns;
+};
+
+enum selftest_obj_type {
+	TYPE_IDEV,
+};
+
+struct selftest_obj {
+	struct iommufd_object obj;
+	enum selftest_obj_type type;
+
+	union {
+		struct {
+			struct iommufd_hw_pagetable *hwpt;
+			struct iommufd_ctx *ictx;
+			struct device mock_dev;
+		} idev;
+	};
+};
+
+static struct iommu_domain *mock_domain_alloc(unsigned int iommu_domain_type)
+{
+	struct mock_iommu_domain *mock;
+
+	if (WARN_ON(iommu_domain_type != IOMMU_DOMAIN_UNMANAGED))
+		return NULL;
+
+	mock = kzalloc(sizeof(*mock), GFP_KERNEL);
+	if (!mock)
+		return NULL;
+	mock->domain.geometry.aperture_start = MOCK_APERTURE_START;
+	mock->domain.geometry.aperture_end = MOCK_APERTURE_LAST;
+	mock->domain.pgsize_bitmap = MOCK_IO_PAGE_SIZE;
+	xa_init(&mock->pfns);
+	return &mock->domain;
+}
+
+static void mock_domain_free(struct iommu_domain *domain)
+{
+	struct mock_iommu_domain *mock =
+		container_of(domain, struct mock_iommu_domain, domain);
+
+	WARN_ON(!xa_empty(&mock->pfns));
+	kfree(mock);
+}
+
+static int mock_domain_map_pages(struct iommu_domain *domain,
+				 unsigned long iova, phys_addr_t paddr,
+				 size_t pgsize, size_t pgcount, int prot,
+				 gfp_t gfp, size_t *mapped)
+{
+	struct mock_iommu_domain *mock =
+		container_of(domain, struct mock_iommu_domain, domain);
+	unsigned long flags = MOCK_PFN_START_IOVA;
+	unsigned long start_iova = iova;
+
+	/*
+	 * xarray does not reliably work with fault injection because it does a
+	 * retry allocation, so put our own failure point.
+	 */
+	if (iommufd_should_fail())
+		return -ENOENT;
+
+	WARN_ON(iova % MOCK_IO_PAGE_SIZE);
+	WARN_ON(pgsize % MOCK_IO_PAGE_SIZE);
+	for (; pgcount; pgcount--) {
+		size_t cur;
+
+		for (cur = 0; cur != pgsize; cur += MOCK_IO_PAGE_SIZE) {
+			void *old;
+
+			if (pgcount == 1 && cur + MOCK_IO_PAGE_SIZE == pgsize)
+				flags = MOCK_PFN_LAST_IOVA;
+			old = xa_store(&mock->pfns, iova / MOCK_IO_PAGE_SIZE,
+				       xa_mk_value((paddr / MOCK_IO_PAGE_SIZE) |
+						   flags),
+				       gfp);
+			if (xa_is_err(old)) {
+				for (; start_iova != iova;
+				     start_iova += MOCK_IO_PAGE_SIZE)
+					xa_erase(&mock->pfns,
+						 start_iova /
+							 MOCK_IO_PAGE_SIZE);
+				return xa_err(old);
+			}
+			WARN_ON(old);
+			iova += MOCK_IO_PAGE_SIZE;
+			paddr += MOCK_IO_PAGE_SIZE;
+			*mapped += MOCK_IO_PAGE_SIZE;
+			flags = 0;
+		}
+	}
+	return 0;
+}
+
+static size_t mock_domain_unmap_pages(struct iommu_domain *domain,
+				      unsigned long iova, size_t pgsize,
+				      size_t pgcount,
+				      struct iommu_iotlb_gather *iotlb_gather)
+{
+	struct mock_iommu_domain *mock =
+		container_of(domain, struct mock_iommu_domain, domain);
+	bool first = true;
+	size_t ret = 0;
+	void *ent;
+
+	WARN_ON(iova % MOCK_IO_PAGE_SIZE);
+	WARN_ON(pgsize % MOCK_IO_PAGE_SIZE);
+
+	for (; pgcount; pgcount--) {
+		size_t cur;
+
+		for (cur = 0; cur != pgsize; cur += MOCK_IO_PAGE_SIZE) {
+			ent = xa_erase(&mock->pfns, iova / MOCK_IO_PAGE_SIZE);
+			WARN_ON(!ent);
+			/*
+			 * iommufd generates unmaps that must be a strict
+			 * superset of the map's performend So every starting
+			 * IOVA should have been an iova passed to map, and the
+			 *
+			 * First IOVA must be present and have been a first IOVA
+			 * passed to map_pages
+			 */
+			if (first) {
+				WARN_ON(!(xa_to_value(ent) &
+					  MOCK_PFN_START_IOVA));
+				first = false;
+			}
+			if (pgcount == 1 && cur + MOCK_IO_PAGE_SIZE == pgsize)
+				WARN_ON(!(xa_to_value(ent) &
+					  MOCK_PFN_LAST_IOVA));
+
+			iova += MOCK_IO_PAGE_SIZE;
+			ret += MOCK_IO_PAGE_SIZE;
+		}
+	}
+	return ret;
+}
+
+static phys_addr_t mock_domain_iova_to_phys(struct iommu_domain *domain,
+					    dma_addr_t iova)
+{
+	struct mock_iommu_domain *mock =
+		container_of(domain, struct mock_iommu_domain, domain);
+	void *ent;
+
+	WARN_ON(iova % MOCK_IO_PAGE_SIZE);
+	ent = xa_load(&mock->pfns, iova / MOCK_IO_PAGE_SIZE);
+	WARN_ON(!ent);
+	return (xa_to_value(ent) & MOCK_PFN_MASK) * MOCK_IO_PAGE_SIZE;
+}
+
+static const struct iommu_ops mock_ops = {
+	.owner = THIS_MODULE,
+	.pgsize_bitmap = MOCK_IO_PAGE_SIZE,
+	.domain_alloc = mock_domain_alloc,
+	.default_domain_ops =
+		&(struct iommu_domain_ops){
+			.free = mock_domain_free,
+			.map_pages = mock_domain_map_pages,
+			.unmap_pages = mock_domain_unmap_pages,
+			.iova_to_phys = mock_domain_iova_to_phys,
+		},
+};
+
+static inline struct iommufd_hw_pagetable *
+get_md_pagetable(struct iommufd_ucmd *ucmd, u32 mockpt_id,
+		 struct mock_iommu_domain **mock)
+{
+	struct iommufd_hw_pagetable *hwpt;
+	struct iommufd_object *obj;
+
+	obj = iommufd_get_object(ucmd->ictx, mockpt_id,
+				 IOMMUFD_OBJ_HW_PAGETABLE);
+	if (IS_ERR(obj))
+		return ERR_CAST(obj);
+	hwpt = container_of(obj, struct iommufd_hw_pagetable, obj);
+	if (hwpt->domain->ops != mock_ops.default_domain_ops) {
+		iommufd_put_object(&hwpt->obj);
+		return ERR_PTR(-EINVAL);
+	}
+	*mock = container_of(hwpt->domain, struct mock_iommu_domain, domain);
+	return hwpt;
+}
+
+/* Create an hw_pagetable with the mock domain so we can test the domain ops */
+static int iommufd_test_mock_domain(struct iommufd_ucmd *ucmd,
+				    struct iommu_test_cmd *cmd)
+{
+	static struct bus_type mock_bus = { .iommu_ops = &mock_ops };
+	struct iommufd_hw_pagetable *hwpt;
+	struct selftest_obj *sobj;
+	struct iommufd_ioas *ioas;
+	int rc;
+
+	ioas = iommufd_get_ioas(ucmd, cmd->id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+
+	sobj = iommufd_object_alloc(ucmd->ictx, sobj, IOMMUFD_OBJ_SELFTEST);
+	if (IS_ERR(sobj)) {
+		rc = PTR_ERR(sobj);
+		goto out_ioas;
+	}
+	sobj->idev.ictx = ucmd->ictx;
+	sobj->type = TYPE_IDEV;
+	sobj->idev.mock_dev.bus = &mock_bus;
+
+	hwpt = iommufd_device_selftest_attach(ucmd->ictx, ioas,
+					      &sobj->idev.mock_dev);
+	if (IS_ERR(hwpt)) {
+		rc = PTR_ERR(hwpt);
+		goto out_sobj;
+	}
+	sobj->idev.hwpt = hwpt;
+
+	/* Userspace must destroy both of these IDs to destroy the object */
+	cmd->mock_domain.out_hwpt_id = hwpt->obj.id;
+	cmd->mock_domain.out_device_id = sobj->obj.id;
+	iommufd_object_finalize(ucmd->ictx, &sobj->obj);
+	iommufd_put_object(&ioas->obj);
+	return iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+
+out_sobj:
+	iommufd_object_abort(ucmd->ictx, &sobj->obj);
+out_ioas:
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+/* Add an additional reserved IOVA to the IOAS */
+static int iommufd_test_add_reserved(struct iommufd_ucmd *ucmd,
+				     unsigned int mockpt_id,
+				     unsigned long start, size_t length)
+{
+	struct iommufd_ioas *ioas;
+	int rc;
+
+	ioas = iommufd_get_ioas(ucmd, mockpt_id);
+	if (IS_ERR(ioas))
+		return PTR_ERR(ioas);
+	down_write(&ioas->iopt.iova_rwsem);
+	rc = iopt_reserve_iova(&ioas->iopt, start, start + length - 1, NULL);
+	up_write(&ioas->iopt.iova_rwsem);
+	iommufd_put_object(&ioas->obj);
+	return rc;
+}
+
+/* Check that every pfn under each iova matches the pfn under a user VA */
+static int iommufd_test_md_check_pa(struct iommufd_ucmd *ucmd,
+				    unsigned int mockpt_id, unsigned long iova,
+				    size_t length, void __user *uptr)
+{
+	struct iommufd_hw_pagetable *hwpt;
+	struct mock_iommu_domain *mock;
+	int rc;
+
+	if (iova % MOCK_IO_PAGE_SIZE || length % MOCK_IO_PAGE_SIZE ||
+	    (uintptr_t)uptr % MOCK_IO_PAGE_SIZE)
+		return -EINVAL;
+
+	hwpt = get_md_pagetable(ucmd, mockpt_id, &mock);
+	if (IS_ERR(hwpt))
+		return PTR_ERR(hwpt);
+
+	for (; length; length -= MOCK_IO_PAGE_SIZE) {
+		struct page *pages[1];
+		unsigned long pfn;
+		long npages;
+		void *ent;
+
+		npages = get_user_pages_fast((uintptr_t)uptr & PAGE_MASK, 1, 0,
+					     pages);
+		if (npages < 0) {
+			rc = npages;
+			goto out_put;
+		}
+		if (WARN_ON(npages != 1)) {
+			rc = -EFAULT;
+			goto out_put;
+		}
+		pfn = page_to_pfn(pages[0]);
+		put_page(pages[0]);
+
+		ent = xa_load(&mock->pfns, iova / MOCK_IO_PAGE_SIZE);
+		if (!ent ||
+		    (xa_to_value(ent) & MOCK_PFN_MASK) * MOCK_IO_PAGE_SIZE !=
+			    pfn * PAGE_SIZE + ((uintptr_t)uptr % PAGE_SIZE)) {
+			rc = -EINVAL;
+			goto out_put;
+		}
+		iova += MOCK_IO_PAGE_SIZE;
+		uptr += MOCK_IO_PAGE_SIZE;
+	}
+	rc = 0;
+
+out_put:
+	iommufd_put_object(&hwpt->obj);
+	return rc;
+}
+
+/* Check that the page ref count matches, to look for missing pin/unpins */
+static int iommufd_test_md_check_refs(struct iommufd_ucmd *ucmd,
+				      void __user *uptr, size_t length,
+				      unsigned int refs)
+{
+	if (length % PAGE_SIZE || (uintptr_t)uptr % PAGE_SIZE)
+		return -EINVAL;
+
+	for (; length; length -= PAGE_SIZE) {
+		struct page *pages[1];
+		long npages;
+
+		npages = get_user_pages_fast((uintptr_t)uptr, 1, 0, pages);
+		if (npages < 0)
+			return npages;
+		if (WARN_ON(npages != 1))
+			return -EFAULT;
+		if (!PageCompound(pages[0])) {
+			unsigned int count;
+
+			count = page_ref_count(pages[0]);
+			if (count / GUP_PIN_COUNTING_BIAS != refs) {
+				put_page(pages[0]);
+				return -EIO;
+			}
+		}
+		put_page(pages[0]);
+		uptr += PAGE_SIZE;
+	}
+	return 0;
+}
+
+struct selftest_access {
+	struct iommufd_access *access;
+	struct file *file;
+	struct mutex lock;
+	struct list_head items;
+	unsigned int next_id;
+	bool destroying;
+};
+
+struct selftest_access_item {
+	struct list_head items_elm;
+	unsigned long iova;
+	size_t length;
+	unsigned int id;
+};
+
+static const struct file_operations iommfd_test_staccess_fops;
+
+static struct selftest_access *iommufd_access_get(int fd)
+{
+	struct file *file;
+
+	file = fget(fd);
+	if (!file)
+		return ERR_PTR(-EBADFD);
+
+	if (file->f_op != &iommfd_test_staccess_fops) {
+		fput(file);
+		return ERR_PTR(-EBADFD);
+	}
+	return file->private_data;
+}
+
+static void iommufd_test_access_unmap(void *data, unsigned long iova,
+				      unsigned long length)
+{
+	unsigned long iova_last = iova + length - 1;
+	struct selftest_access *staccess = data;
+	struct selftest_access_item *item;
+	struct selftest_access_item *tmp;
+
+	mutex_lock(&staccess->lock);
+	list_for_each_entry_safe(item, tmp, &staccess->items, items_elm) {
+		if (iova > item->iova + item->length - 1 ||
+		    iova_last < item->iova)
+			continue;
+		list_del(&item->items_elm);
+		iommufd_access_unpin_pages(staccess->access, item->iova,
+					   item->length);
+		kfree(item);
+	}
+	mutex_unlock(&staccess->lock);
+}
+
+static int iommufd_test_access_item_destroy(struct iommufd_ucmd *ucmd,
+					    unsigned int access_id,
+					    unsigned int item_id)
+{
+	struct selftest_access_item *item;
+	struct selftest_access *staccess;
+
+	staccess = iommufd_access_get(access_id);
+	if (IS_ERR(staccess))
+		return PTR_ERR(staccess);
+
+	mutex_lock(&staccess->lock);
+	list_for_each_entry(item, &staccess->items, items_elm) {
+		if (item->id == item_id) {
+			list_del(&item->items_elm);
+			iommufd_access_unpin_pages(staccess->access, item->iova,
+						   item->length);
+			mutex_unlock(&staccess->lock);
+			kfree(item);
+			fput(staccess->file);
+			return 0;
+		}
+	}
+	mutex_unlock(&staccess->lock);
+	fput(staccess->file);
+	return -ENOENT;
+}
+
+static int iommufd_test_staccess_release(struct inode *inode,
+					 struct file *filep)
+{
+	struct selftest_access *staccess = filep->private_data;
+
+	if (staccess->access) {
+		iommufd_test_access_unmap(staccess, 0, ULONG_MAX);
+		iommufd_access_destroy(staccess->access);
+	}
+	mutex_destroy(&staccess->lock);
+	kfree(staccess);
+	return 0;
+}
+
+static const struct iommufd_access_ops selftest_access_ops_pin = {
+	.needs_pin_pages = 1,
+	.unmap = iommufd_test_access_unmap,
+};
+
+static const struct iommufd_access_ops selftest_access_ops = {
+	.unmap = iommufd_test_access_unmap,
+};
+
+static const struct file_operations iommfd_test_staccess_fops = {
+	.release = iommufd_test_staccess_release,
+};
+
+static struct selftest_access *iommufd_test_alloc_access(void)
+{
+	struct selftest_access *staccess;
+	struct file *filep;
+
+	staccess = kzalloc(sizeof(*staccess), GFP_KERNEL_ACCOUNT);
+	if (!staccess)
+		return ERR_PTR(-ENOMEM);
+	INIT_LIST_HEAD(&staccess->items);
+	mutex_init(&staccess->lock);
+
+	filep = anon_inode_getfile("[iommufd_test_staccess]",
+				   &iommfd_test_staccess_fops, staccess,
+				   O_RDWR);
+	if (IS_ERR(filep)) {
+		kfree(staccess);
+		return ERR_CAST(filep);
+	}
+	staccess->file = filep;
+	return staccess;
+}
+
+static int iommufd_test_create_access(struct iommufd_ucmd *ucmd,
+				      unsigned int ioas_id, unsigned int flags)
+{
+	struct iommu_test_cmd *cmd = ucmd->cmd;
+	struct selftest_access *staccess;
+	struct iommufd_access *access;
+	int fdno;
+	int rc;
+
+	if (flags & ~MOCK_FLAGS_ACCESS_CREATE_NEEDS_PIN_PAGES)
+		return -EOPNOTSUPP;
+
+	staccess = iommufd_test_alloc_access();
+	if (IS_ERR(staccess))
+		return PTR_ERR(staccess);
+
+	fdno = get_unused_fd_flags(O_CLOEXEC);
+	if (fdno < 0) {
+		rc = -ENOMEM;
+		goto out_free_staccess;
+	}
+
+	access = iommufd_access_create(
+		ucmd->ictx, ioas_id,
+		(flags & MOCK_FLAGS_ACCESS_CREATE_NEEDS_PIN_PAGES) ?
+			&selftest_access_ops_pin :
+			&selftest_access_ops,
+		staccess);
+	if (IS_ERR(access)) {
+		rc = PTR_ERR(access);
+		goto out_put_fdno;
+	}
+	cmd->create_access.out_access_fd = fdno;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+	if (rc)
+		goto out_destroy;
+
+	staccess->access = access;
+	fd_install(fdno, staccess->file);
+	return 0;
+
+out_destroy:
+	iommufd_access_destroy(access);
+out_put_fdno:
+	put_unused_fd(fdno);
+out_free_staccess:
+	fput(staccess->file);
+	return rc;
+}
+
+/* Check that the pages in a page array match the pages in the user VA */
+static int iommufd_test_check_pages(void __user *uptr, struct page **pages,
+				    size_t npages)
+{
+	for (; npages; npages--) {
+		struct page *tmp_pages[1];
+		long rc;
+
+		rc = get_user_pages_fast((uintptr_t)uptr, 1, 0, tmp_pages);
+		if (rc < 0)
+			return rc;
+		if (WARN_ON(rc != 1))
+			return -EFAULT;
+		put_page(tmp_pages[0]);
+		if (tmp_pages[0] != *pages)
+			return -EBADE;
+		pages++;
+		uptr += PAGE_SIZE;
+	}
+	return 0;
+}
+
+static int iommufd_test_access_pages(struct iommufd_ucmd *ucmd,
+				     unsigned int access_id, unsigned long iova,
+				     size_t length, void __user *uptr,
+				     u32 flags)
+{
+	struct iommu_test_cmd *cmd = ucmd->cmd;
+	struct selftest_access_item *item;
+	struct selftest_access *staccess;
+	struct page **pages;
+	size_t npages;
+	int rc;
+
+	/* Prevent syzkaller from triggering a WARN_ON in kvzalloc() */
+	if (length > 16*1024*1024)
+		return -ENOMEM;
+
+	if (flags & ~(MOCK_FLAGS_ACCESS_WRITE | MOCK_FLAGS_ACCESS_SYZ))
+		return -EOPNOTSUPP;
+
+	staccess = iommufd_access_get(access_id);
+	if (IS_ERR(staccess))
+		return PTR_ERR(staccess);
+
+	if (staccess->access->ops != &selftest_access_ops_pin) {
+		rc = -EOPNOTSUPP;
+		goto out_put;
+	}
+
+	if (flags & MOCK_FLAGS_ACCESS_SYZ)
+		iova = iommufd_test_syz_conv_iova(&staccess->access->ioas->iopt,
+					&cmd->access_pages.iova);
+
+	npages = (ALIGN(iova + length, PAGE_SIZE) -
+		  ALIGN_DOWN(iova, PAGE_SIZE)) /
+		 PAGE_SIZE;
+	pages = kvcalloc(npages, sizeof(*pages), GFP_KERNEL_ACCOUNT);
+	if (!pages) {
+		rc = -ENOMEM;
+		goto out_put;
+	}
+
+	/*
+	 * Drivers will need to think very carefully about this locking. The
+	 * core code can do multiple unmaps instantaneously after
+	 * iommufd_access_pin_pages() and *all* the unmaps must not return until
+	 * the range is unpinned. This simple implementation puts a global lock
+	 * around the pin, which may not suit drivers that want this to be a
+	 * performance path. drivers that get this wrong will trigger WARN_ON
+	 * races and cause EDEADLOCK failures to userspace.
+	 */
+	mutex_lock(&staccess->lock);
+	rc = iommufd_access_pin_pages(staccess->access, iova, length, pages,
+				      flags & MOCK_FLAGS_ACCESS_WRITE);
+	if (rc)
+		goto out_unlock;
+
+	/* For syzkaller allow uptr to be NULL to skip this check */
+	if (uptr) {
+		rc = iommufd_test_check_pages(
+			uptr - (iova - ALIGN_DOWN(iova, PAGE_SIZE)), pages,
+			npages);
+		if (rc)
+			goto out_unaccess;
+	}
+
+	item = kzalloc(sizeof(*item), GFP_KERNEL_ACCOUNT);
+	if (!item) {
+		rc = -ENOMEM;
+		goto out_unaccess;
+	}
+
+	item->iova = iova;
+	item->length = length;
+	item->id = staccess->next_id++;
+	list_add_tail(&item->items_elm, &staccess->items);
+
+	cmd->access_pages.out_access_pages_id = item->id;
+	rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+	if (rc)
+		goto out_free_item;
+	goto out_unlock;
+
+out_free_item:
+	list_del(&item->items_elm);
+	kfree(item);
+out_unaccess:
+	iommufd_access_unpin_pages(staccess->access, iova, length);
+out_unlock:
+	mutex_unlock(&staccess->lock);
+	kvfree(pages);
+out_put:
+	fput(staccess->file);
+	return rc;
+}
+
+static int iommufd_test_access_rw(struct iommufd_ucmd *ucmd,
+				  unsigned int access_id, unsigned long iova,
+				  size_t length, void __user *ubuf,
+				  unsigned int flags)
+{
+	struct iommu_test_cmd *cmd = ucmd->cmd;
+	struct selftest_access *staccess;
+	void *tmp;
+	int rc;
+
+	/* Prevent syzkaller from triggering a WARN_ON in kvzalloc() */
+	if (length > 16*1024*1024)
+		return -ENOMEM;
+
+	if (flags & ~(MOCK_ACCESS_RW_WRITE | MOCK_ACCESS_RW_SLOW_PATH |
+		      MOCK_FLAGS_ACCESS_SYZ))
+		return -EOPNOTSUPP;
+
+	staccess = iommufd_access_get(access_id);
+	if (IS_ERR(staccess))
+		return PTR_ERR(staccess);
+
+	tmp = kvzalloc(length, GFP_KERNEL_ACCOUNT);
+	if (!tmp) {
+		rc = -ENOMEM;
+		goto out_put;
+	}
+
+	if (flags & MOCK_ACCESS_RW_WRITE) {
+		if (copy_from_user(tmp, ubuf, length)) {
+			rc = -EFAULT;
+			goto out_free;
+		}
+	}
+
+	if (flags & MOCK_FLAGS_ACCESS_SYZ)
+		iova = iommufd_test_syz_conv_iova(&staccess->access->ioas->iopt,
+					&cmd->access_rw.iova);
+
+	rc = iommufd_access_rw(staccess->access, iova, tmp, length, flags);
+	if (rc)
+		goto out_free;
+	if (!(flags & MOCK_ACCESS_RW_WRITE)) {
+		if (copy_to_user(ubuf, tmp, length)) {
+			rc = -EFAULT;
+			goto out_free;
+		}
+	}
+
+out_free:
+	kvfree(tmp);
+out_put:
+	fput(staccess->file);
+	return rc;
+}
+static_assert((unsigned int)MOCK_ACCESS_RW_WRITE == IOMMUFD_ACCESS_RW_WRITE);
+static_assert((unsigned int)MOCK_ACCESS_RW_SLOW_PATH ==
+	      __IOMMUFD_ACCESS_RW_SLOW_PATH);
+
+void iommufd_selftest_destroy(struct iommufd_object *obj)
+{
+	struct selftest_obj *sobj = container_of(obj, struct selftest_obj, obj);
+
+	switch (sobj->type) {
+	case TYPE_IDEV:
+		iommufd_device_selftest_detach(sobj->idev.ictx,
+					       sobj->idev.hwpt);
+		break;
+	}
+}
+
+int iommufd_test(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_test_cmd *cmd = ucmd->cmd;
+
+	switch (cmd->op) {
+	case IOMMU_TEST_OP_ADD_RESERVED:
+		return iommufd_test_add_reserved(ucmd, cmd->id,
+						 cmd->add_reserved.start,
+						 cmd->add_reserved.length);
+	case IOMMU_TEST_OP_MOCK_DOMAIN:
+		return iommufd_test_mock_domain(ucmd, cmd);
+	case IOMMU_TEST_OP_MD_CHECK_MAP:
+		return iommufd_test_md_check_pa(
+			ucmd, cmd->id, cmd->check_map.iova,
+			cmd->check_map.length,
+			u64_to_user_ptr(cmd->check_map.uptr));
+	case IOMMU_TEST_OP_MD_CHECK_REFS:
+		return iommufd_test_md_check_refs(
+			ucmd, u64_to_user_ptr(cmd->check_refs.uptr),
+			cmd->check_refs.length, cmd->check_refs.refs);
+	case IOMMU_TEST_OP_CREATE_ACCESS:
+		return iommufd_test_create_access(ucmd, cmd->id,
+						  cmd->create_access.flags);
+	case IOMMU_TEST_OP_ACCESS_PAGES:
+		return iommufd_test_access_pages(
+			ucmd, cmd->id, cmd->access_pages.iova,
+			cmd->access_pages.length,
+			u64_to_user_ptr(cmd->access_pages.uptr),
+			cmd->access_pages.flags);
+	case IOMMU_TEST_OP_ACCESS_RW:
+		return iommufd_test_access_rw(
+			ucmd, cmd->id, cmd->access_rw.iova,
+			cmd->access_rw.length,
+			u64_to_user_ptr(cmd->access_rw.uptr),
+			cmd->access_rw.flags);
+	case IOMMU_TEST_OP_DESTROY_ACCESS_PAGES:
+		return iommufd_test_access_item_destroy(
+			ucmd, cmd->id, cmd->destroy_access_pages.access_pages_id);
+	case IOMMU_TEST_OP_SET_TEMP_MEMORY_LIMIT:
+		/* Protect _batch_init(), can not be less than elmsz */
+		if (cmd->memory_limit.limit <
+		    sizeof(unsigned long) + sizeof(u32))
+			return -EINVAL;
+		iommufd_test_memory_limit = cmd->memory_limit.limit;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+bool iommufd_should_fail(void)
+{
+	return should_fail(&fail_iommufd, 1);
+}
+
+void __init iommufd_test_init(void)
+{
+	dbgfs_root =
+		fault_create_debugfs_attr("fail_iommufd", NULL, &fail_iommufd);
+}
+
+void iommufd_test_exit(void)
+{
+	debugfs_remove_recursive(dbgfs_root);
+}