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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/arm64/kernel/machine_kexec.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/arm64/kernel/machine_kexec.c')
-rw-r--r--arch/arm64/kernel/machine_kexec.c363
1 files changed, 363 insertions, 0 deletions
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
new file mode 100644
index 000000000..ce3d40120
--- /dev/null
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -0,0 +1,363 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * kexec for arm64
+ *
+ * Copyright (C) Linaro.
+ * Copyright (C) Huawei Futurewei Technologies.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/page-flags.h>
+#include <linux/set_memory.h>
+#include <linux/smp.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cpu_ops.h>
+#include <asm/daifflags.h>
+#include <asm/memory.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/page.h>
+#include <asm/sections.h>
+#include <asm/trans_pgd.h>
+
+/**
+ * kexec_image_info - For debugging output.
+ */
+#define kexec_image_info(_i) _kexec_image_info(__func__, __LINE__, _i)
+static void _kexec_image_info(const char *func, int line,
+ const struct kimage *kimage)
+{
+ unsigned long i;
+
+ pr_debug("%s:%d:\n", func, line);
+ pr_debug(" kexec kimage info:\n");
+ pr_debug(" type: %d\n", kimage->type);
+ pr_debug(" start: %lx\n", kimage->start);
+ pr_debug(" head: %lx\n", kimage->head);
+ pr_debug(" nr_segments: %lu\n", kimage->nr_segments);
+ pr_debug(" dtb_mem: %pa\n", &kimage->arch.dtb_mem);
+ pr_debug(" kern_reloc: %pa\n", &kimage->arch.kern_reloc);
+ pr_debug(" el2_vectors: %pa\n", &kimage->arch.el2_vectors);
+
+ for (i = 0; i < kimage->nr_segments; i++) {
+ pr_debug(" segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",
+ i,
+ kimage->segment[i].mem,
+ kimage->segment[i].mem + kimage->segment[i].memsz,
+ kimage->segment[i].memsz,
+ kimage->segment[i].memsz / PAGE_SIZE);
+ }
+}
+
+void machine_kexec_cleanup(struct kimage *kimage)
+{
+ /* Empty routine needed to avoid build errors. */
+}
+
+/**
+ * machine_kexec_prepare - Prepare for a kexec reboot.
+ *
+ * Called from the core kexec code when a kernel image is loaded.
+ * Forbid loading a kexec kernel if we have no way of hotplugging cpus or cpus
+ * are stuck in the kernel. This avoids a panic once we hit machine_kexec().
+ */
+int machine_kexec_prepare(struct kimage *kimage)
+{
+ if (kimage->type != KEXEC_TYPE_CRASH && cpus_are_stuck_in_kernel()) {
+ pr_err("Can't kexec: CPUs are stuck in the kernel.\n");
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+/**
+ * kexec_segment_flush - Helper to flush the kimage segments to PoC.
+ */
+static void kexec_segment_flush(const struct kimage *kimage)
+{
+ unsigned long i;
+
+ pr_debug("%s:\n", __func__);
+
+ for (i = 0; i < kimage->nr_segments; i++) {
+ pr_debug(" segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",
+ i,
+ kimage->segment[i].mem,
+ kimage->segment[i].mem + kimage->segment[i].memsz,
+ kimage->segment[i].memsz,
+ kimage->segment[i].memsz / PAGE_SIZE);
+
+ dcache_clean_inval_poc(
+ (unsigned long)phys_to_virt(kimage->segment[i].mem),
+ (unsigned long)phys_to_virt(kimage->segment[i].mem) +
+ kimage->segment[i].memsz);
+ }
+}
+
+/* Allocates pages for kexec page table */
+static void *kexec_page_alloc(void *arg)
+{
+ struct kimage *kimage = (struct kimage *)arg;
+ struct page *page = kimage_alloc_control_pages(kimage, 0);
+ void *vaddr = NULL;
+
+ if (!page)
+ return NULL;
+
+ vaddr = page_address(page);
+ memset(vaddr, 0, PAGE_SIZE);
+
+ return vaddr;
+}
+
+int machine_kexec_post_load(struct kimage *kimage)
+{
+ int rc;
+ pgd_t *trans_pgd;
+ void *reloc_code = page_to_virt(kimage->control_code_page);
+ long reloc_size;
+ struct trans_pgd_info info = {
+ .trans_alloc_page = kexec_page_alloc,
+ .trans_alloc_arg = kimage,
+ };
+
+ /* If in place, relocation is not used, only flush next kernel */
+ if (kimage->head & IND_DONE) {
+ kexec_segment_flush(kimage);
+ kexec_image_info(kimage);
+ return 0;
+ }
+
+ kimage->arch.el2_vectors = 0;
+ if (is_hyp_nvhe()) {
+ rc = trans_pgd_copy_el2_vectors(&info,
+ &kimage->arch.el2_vectors);
+ if (rc)
+ return rc;
+ }
+
+ /* Create a copy of the linear map */
+ trans_pgd = kexec_page_alloc(kimage);
+ if (!trans_pgd)
+ return -ENOMEM;
+ rc = trans_pgd_create_copy(&info, &trans_pgd, PAGE_OFFSET, PAGE_END);
+ if (rc)
+ return rc;
+ kimage->arch.ttbr1 = __pa(trans_pgd);
+ kimage->arch.zero_page = __pa_symbol(empty_zero_page);
+
+ reloc_size = __relocate_new_kernel_end - __relocate_new_kernel_start;
+ memcpy(reloc_code, __relocate_new_kernel_start, reloc_size);
+ kimage->arch.kern_reloc = __pa(reloc_code);
+ rc = trans_pgd_idmap_page(&info, &kimage->arch.ttbr0,
+ &kimage->arch.t0sz, reloc_code);
+ if (rc)
+ return rc;
+ kimage->arch.phys_offset = virt_to_phys(kimage) - (long)kimage;
+
+ /* Flush the reloc_code in preparation for its execution. */
+ dcache_clean_inval_poc((unsigned long)reloc_code,
+ (unsigned long)reloc_code + reloc_size);
+ icache_inval_pou((uintptr_t)reloc_code,
+ (uintptr_t)reloc_code + reloc_size);
+ kexec_image_info(kimage);
+
+ return 0;
+}
+
+/**
+ * machine_kexec - Do the kexec reboot.
+ *
+ * Called from the core kexec code for a sys_reboot with LINUX_REBOOT_CMD_KEXEC.
+ */
+void machine_kexec(struct kimage *kimage)
+{
+ bool in_kexec_crash = (kimage == kexec_crash_image);
+ bool stuck_cpus = cpus_are_stuck_in_kernel();
+
+ /*
+ * New cpus may have become stuck_in_kernel after we loaded the image.
+ */
+ BUG_ON(!in_kexec_crash && (stuck_cpus || (num_online_cpus() > 1)));
+ WARN(in_kexec_crash && (stuck_cpus || smp_crash_stop_failed()),
+ "Some CPUs may be stale, kdump will be unreliable.\n");
+
+ pr_info("Bye!\n");
+
+ local_daif_mask();
+
+ /*
+ * Both restart and kernel_reloc will shutdown the MMU, disable data
+ * caches. However, restart will start new kernel or purgatory directly,
+ * kernel_reloc contains the body of arm64_relocate_new_kernel
+ * In kexec case, kimage->start points to purgatory assuming that
+ * kernel entry and dtb address are embedded in purgatory by
+ * userspace (kexec-tools).
+ * In kexec_file case, the kernel starts directly without purgatory.
+ */
+ if (kimage->head & IND_DONE) {
+ typeof(cpu_soft_restart) *restart;
+
+ cpu_install_idmap();
+ restart = (void *)__pa_symbol(cpu_soft_restart);
+ restart(is_hyp_nvhe(), kimage->start, kimage->arch.dtb_mem,
+ 0, 0);
+ } else {
+ void (*kernel_reloc)(struct kimage *kimage);
+
+ if (is_hyp_nvhe())
+ __hyp_set_vectors(kimage->arch.el2_vectors);
+ cpu_install_ttbr0(kimage->arch.ttbr0, kimage->arch.t0sz);
+ kernel_reloc = (void *)kimage->arch.kern_reloc;
+ kernel_reloc(kimage);
+ }
+
+ BUG(); /* Should never get here. */
+}
+
+static void machine_kexec_mask_interrupts(void)
+{
+ unsigned int i;
+ struct irq_desc *desc;
+
+ for_each_irq_desc(i, desc) {
+ struct irq_chip *chip;
+ int ret;
+
+ chip = irq_desc_get_chip(desc);
+ if (!chip)
+ continue;
+
+ /*
+ * First try to remove the active state. If this
+ * fails, try to EOI the interrupt.
+ */
+ ret = irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false);
+
+ if (ret && irqd_irq_inprogress(&desc->irq_data) &&
+ chip->irq_eoi)
+ chip->irq_eoi(&desc->irq_data);
+
+ if (chip->irq_mask)
+ chip->irq_mask(&desc->irq_data);
+
+ if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
+ chip->irq_disable(&desc->irq_data);
+ }
+}
+
+/**
+ * machine_crash_shutdown - shutdown non-crashing cpus and save registers
+ */
+void machine_crash_shutdown(struct pt_regs *regs)
+{
+ local_irq_disable();
+
+ /* shutdown non-crashing cpus */
+ crash_smp_send_stop();
+
+ /* for crashing cpu */
+ crash_save_cpu(regs, smp_processor_id());
+ machine_kexec_mask_interrupts();
+
+ pr_info("Starting crashdump kernel...\n");
+}
+
+void arch_kexec_protect_crashkres(void)
+{
+ int i;
+
+ for (i = 0; i < kexec_crash_image->nr_segments; i++)
+ set_memory_valid(
+ __phys_to_virt(kexec_crash_image->segment[i].mem),
+ kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 0);
+}
+
+void arch_kexec_unprotect_crashkres(void)
+{
+ int i;
+
+ for (i = 0; i < kexec_crash_image->nr_segments; i++)
+ set_memory_valid(
+ __phys_to_virt(kexec_crash_image->segment[i].mem),
+ kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 1);
+}
+
+#ifdef CONFIG_HIBERNATION
+/*
+ * To preserve the crash dump kernel image, the relevant memory segments
+ * should be mapped again around the hibernation.
+ */
+void crash_prepare_suspend(void)
+{
+ if (kexec_crash_image)
+ arch_kexec_unprotect_crashkres();
+}
+
+void crash_post_resume(void)
+{
+ if (kexec_crash_image)
+ arch_kexec_protect_crashkres();
+}
+
+/*
+ * crash_is_nosave
+ *
+ * Return true only if a page is part of reserved memory for crash dump kernel,
+ * but does not hold any data of loaded kernel image.
+ *
+ * Note that all the pages in crash dump kernel memory have been initially
+ * marked as Reserved as memory was allocated via memblock_reserve().
+ *
+ * In hibernation, the pages which are Reserved and yet "nosave" are excluded
+ * from the hibernation iamge. crash_is_nosave() does thich check for crash
+ * dump kernel and will reduce the total size of hibernation image.
+ */
+
+bool crash_is_nosave(unsigned long pfn)
+{
+ int i;
+ phys_addr_t addr;
+
+ if (!crashk_res.end)
+ return false;
+
+ /* in reserved memory? */
+ addr = __pfn_to_phys(pfn);
+ if ((addr < crashk_res.start) || (crashk_res.end < addr)) {
+ if (!crashk_low_res.end)
+ return false;
+
+ if ((addr < crashk_low_res.start) || (crashk_low_res.end < addr))
+ return false;
+ }
+
+ if (!kexec_crash_image)
+ return true;
+
+ /* not part of loaded kernel image? */
+ for (i = 0; i < kexec_crash_image->nr_segments; i++)
+ if (addr >= kexec_crash_image->segment[i].mem &&
+ addr < (kexec_crash_image->segment[i].mem +
+ kexec_crash_image->segment[i].memsz))
+ return false;
+
+ return true;
+}
+
+void crash_free_reserved_phys_range(unsigned long begin, unsigned long end)
+{
+ unsigned long addr;
+ struct page *page;
+
+ for (addr = begin; addr < end; addr += PAGE_SIZE) {
+ page = phys_to_page(addr);
+ free_reserved_page(page);
+ }
+}
+#endif /* CONFIG_HIBERNATION */