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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/arm64/kernel/hibernate.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
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/hibernate.c')
-rw-r--r-- | arch/arm64/kernel/hibernate.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c new file mode 100644 index 000000000..788597a6b --- /dev/null +++ b/arch/arm64/kernel/hibernate.c @@ -0,0 +1,478 @@ +// SPDX-License-Identifier: GPL-2.0-only +/*: + * Hibernate support specific for ARM64 + * + * Derived from work on ARM hibernation support by: + * + * Ubuntu project, hibernation support for mach-dove + * Copyright (C) 2010 Nokia Corporation (Hiroshi Doyu) + * Copyright (C) 2010 Texas Instruments, Inc. (Teerth Reddy et al.) + * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> + */ +#define pr_fmt(x) "hibernate: " x +#include <linux/cpu.h> +#include <linux/kvm_host.h> +#include <linux/pm.h> +#include <linux/sched.h> +#include <linux/suspend.h> +#include <linux/utsname.h> + +#include <asm/barrier.h> +#include <asm/cacheflush.h> +#include <asm/cputype.h> +#include <asm/daifflags.h> +#include <asm/irqflags.h> +#include <asm/kexec.h> +#include <asm/memory.h> +#include <asm/mmu_context.h> +#include <asm/mte.h> +#include <asm/sections.h> +#include <asm/smp.h> +#include <asm/smp_plat.h> +#include <asm/suspend.h> +#include <asm/sysreg.h> +#include <asm/trans_pgd.h> +#include <asm/virt.h> + +/* + * Hibernate core relies on this value being 0 on resume, and marks it + * __nosavedata assuming it will keep the resume kernel's '0' value. This + * doesn't happen with either KASLR. + * + * defined as "__visible int in_suspend __nosavedata" in + * kernel/power/hibernate.c + */ +extern int in_suspend; + +/* Do we need to reset el2? */ +#define el2_reset_needed() (is_hyp_nvhe()) + +/* hyp-stub vectors, used to restore el2 during resume from hibernate. */ +extern char __hyp_stub_vectors[]; + +/* + * The logical cpu number we should resume on, initialised to a non-cpu + * number. + */ +static int sleep_cpu = -EINVAL; + +/* + * Values that may not change over hibernate/resume. We put the build number + * and date in here so that we guarantee not to resume with a different + * kernel. + */ +struct arch_hibernate_hdr_invariants { + char uts_version[__NEW_UTS_LEN + 1]; +}; + +/* These values need to be know across a hibernate/restore. */ +static struct arch_hibernate_hdr { + struct arch_hibernate_hdr_invariants invariants; + + /* These are needed to find the relocated kernel if built with kaslr */ + phys_addr_t ttbr1_el1; + void (*reenter_kernel)(void); + + /* + * We need to know where the __hyp_stub_vectors are after restore to + * re-configure el2. + */ + phys_addr_t __hyp_stub_vectors; + + u64 sleep_cpu_mpidr; +} resume_hdr; + +static inline void arch_hdr_invariants(struct arch_hibernate_hdr_invariants *i) +{ + memset(i, 0, sizeof(*i)); + memcpy(i->uts_version, init_utsname()->version, sizeof(i->uts_version)); +} + +int pfn_is_nosave(unsigned long pfn) +{ + unsigned long nosave_begin_pfn = sym_to_pfn(&__nosave_begin); + unsigned long nosave_end_pfn = sym_to_pfn(&__nosave_end - 1); + + return ((pfn >= nosave_begin_pfn) && (pfn <= nosave_end_pfn)) || + crash_is_nosave(pfn); +} + +void notrace save_processor_state(void) +{ + WARN_ON(num_online_cpus() != 1); +} + +void notrace restore_processor_state(void) +{ +} + +int arch_hibernation_header_save(void *addr, unsigned int max_size) +{ + struct arch_hibernate_hdr *hdr = addr; + + if (max_size < sizeof(*hdr)) + return -EOVERFLOW; + + arch_hdr_invariants(&hdr->invariants); + hdr->ttbr1_el1 = __pa_symbol(swapper_pg_dir); + hdr->reenter_kernel = _cpu_resume; + + /* We can't use __hyp_get_vectors() because kvm may still be loaded */ + if (el2_reset_needed()) + hdr->__hyp_stub_vectors = __pa_symbol(__hyp_stub_vectors); + else + hdr->__hyp_stub_vectors = 0; + + /* Save the mpidr of the cpu we called cpu_suspend() on... */ + if (sleep_cpu < 0) { + pr_err("Failing to hibernate on an unknown CPU.\n"); + return -ENODEV; + } + hdr->sleep_cpu_mpidr = cpu_logical_map(sleep_cpu); + pr_info("Hibernating on CPU %d [mpidr:0x%llx]\n", sleep_cpu, + hdr->sleep_cpu_mpidr); + + return 0; +} +EXPORT_SYMBOL(arch_hibernation_header_save); + +int arch_hibernation_header_restore(void *addr) +{ + int ret; + struct arch_hibernate_hdr_invariants invariants; + struct arch_hibernate_hdr *hdr = addr; + + arch_hdr_invariants(&invariants); + if (memcmp(&hdr->invariants, &invariants, sizeof(invariants))) { + pr_crit("Hibernate image not generated by this kernel!\n"); + return -EINVAL; + } + + sleep_cpu = get_logical_index(hdr->sleep_cpu_mpidr); + pr_info("Hibernated on CPU %d [mpidr:0x%llx]\n", sleep_cpu, + hdr->sleep_cpu_mpidr); + if (sleep_cpu < 0) { + pr_crit("Hibernated on a CPU not known to this kernel!\n"); + sleep_cpu = -EINVAL; + return -EINVAL; + } + + ret = bringup_hibernate_cpu(sleep_cpu); + if (ret) { + sleep_cpu = -EINVAL; + return ret; + } + + resume_hdr = *hdr; + + return 0; +} +EXPORT_SYMBOL(arch_hibernation_header_restore); + +static void *hibernate_page_alloc(void *arg) +{ + return (void *)get_safe_page((__force gfp_t)(unsigned long)arg); +} + +/* + * Copies length bytes, starting at src_start into an new page, + * perform cache maintenance, then maps it at the specified address low + * address as executable. + * + * This is used by hibernate to copy the code it needs to execute when + * overwriting the kernel text. This function generates a new set of page + * tables, which it loads into ttbr0. + * + * Length is provided as we probably only want 4K of data, even on a 64K + * page system. + */ +static int create_safe_exec_page(void *src_start, size_t length, + phys_addr_t *phys_dst_addr) +{ + struct trans_pgd_info trans_info = { + .trans_alloc_page = hibernate_page_alloc, + .trans_alloc_arg = (__force void *)GFP_ATOMIC, + }; + + void *page = (void *)get_safe_page(GFP_ATOMIC); + phys_addr_t trans_ttbr0; + unsigned long t0sz; + int rc; + + if (!page) + return -ENOMEM; + + memcpy(page, src_start, length); + caches_clean_inval_pou((unsigned long)page, (unsigned long)page + length); + rc = trans_pgd_idmap_page(&trans_info, &trans_ttbr0, &t0sz, page); + if (rc) + return rc; + + cpu_install_ttbr0(trans_ttbr0, t0sz); + *phys_dst_addr = virt_to_phys(page); + + return 0; +} + +#ifdef CONFIG_ARM64_MTE + +static DEFINE_XARRAY(mte_pages); + +static int save_tags(struct page *page, unsigned long pfn) +{ + void *tag_storage, *ret; + + tag_storage = mte_allocate_tag_storage(); + if (!tag_storage) + return -ENOMEM; + + mte_save_page_tags(page_address(page), tag_storage); + + ret = xa_store(&mte_pages, pfn, tag_storage, GFP_KERNEL); + if (WARN(xa_is_err(ret), "Failed to store MTE tags")) { + mte_free_tag_storage(tag_storage); + return xa_err(ret); + } else if (WARN(ret, "swsusp: %s: Duplicate entry", __func__)) { + mte_free_tag_storage(ret); + } + + return 0; +} + +static void swsusp_mte_free_storage(void) +{ + XA_STATE(xa_state, &mte_pages, 0); + void *tags; + + xa_lock(&mte_pages); + xas_for_each(&xa_state, tags, ULONG_MAX) { + mte_free_tag_storage(tags); + } + xa_unlock(&mte_pages); + + xa_destroy(&mte_pages); +} + +static int swsusp_mte_save_tags(void) +{ + struct zone *zone; + unsigned long pfn, max_zone_pfn; + int ret = 0; + int n = 0; + + if (!system_supports_mte()) + return 0; + + for_each_populated_zone(zone) { + max_zone_pfn = zone_end_pfn(zone); + for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { + struct page *page = pfn_to_online_page(pfn); + + if (!page) + continue; + + if (!page_mte_tagged(page)) + continue; + + ret = save_tags(page, pfn); + if (ret) { + swsusp_mte_free_storage(); + goto out; + } + + n++; + } + } + pr_info("Saved %d MTE pages\n", n); + +out: + return ret; +} + +static void swsusp_mte_restore_tags(void) +{ + XA_STATE(xa_state, &mte_pages, 0); + int n = 0; + void *tags; + + xa_lock(&mte_pages); + xas_for_each(&xa_state, tags, ULONG_MAX) { + unsigned long pfn = xa_state.xa_index; + struct page *page = pfn_to_online_page(pfn); + + mte_restore_page_tags(page_address(page), tags); + + mte_free_tag_storage(tags); + n++; + } + xa_unlock(&mte_pages); + + pr_info("Restored %d MTE pages\n", n); + + xa_destroy(&mte_pages); +} + +#else /* CONFIG_ARM64_MTE */ + +static int swsusp_mte_save_tags(void) +{ + return 0; +} + +static void swsusp_mte_restore_tags(void) +{ +} + +#endif /* CONFIG_ARM64_MTE */ + +int swsusp_arch_suspend(void) +{ + int ret = 0; + unsigned long flags; + struct sleep_stack_data state; + + if (cpus_are_stuck_in_kernel()) { + pr_err("Can't hibernate: no mechanism to offline secondary CPUs.\n"); + return -EBUSY; + } + + flags = local_daif_save(); + + if (__cpu_suspend_enter(&state)) { + /* make the crash dump kernel image visible/saveable */ + crash_prepare_suspend(); + + ret = swsusp_mte_save_tags(); + if (ret) + return ret; + + sleep_cpu = smp_processor_id(); + ret = swsusp_save(); + } else { + /* Clean kernel core startup/idle code to PoC*/ + dcache_clean_inval_poc((unsigned long)__mmuoff_data_start, + (unsigned long)__mmuoff_data_end); + dcache_clean_inval_poc((unsigned long)__idmap_text_start, + (unsigned long)__idmap_text_end); + + /* Clean kvm setup code to PoC? */ + if (el2_reset_needed()) { + dcache_clean_inval_poc( + (unsigned long)__hyp_idmap_text_start, + (unsigned long)__hyp_idmap_text_end); + dcache_clean_inval_poc((unsigned long)__hyp_text_start, + (unsigned long)__hyp_text_end); + } + + swsusp_mte_restore_tags(); + + /* make the crash dump kernel image protected again */ + crash_post_resume(); + + /* + * Tell the hibernation core that we've just restored + * the memory + */ + in_suspend = 0; + + sleep_cpu = -EINVAL; + __cpu_suspend_exit(); + + /* + * Just in case the boot kernel did turn the SSBD + * mitigation off behind our back, let's set the state + * to what we expect it to be. + */ + spectre_v4_enable_mitigation(NULL); + } + + local_daif_restore(flags); + + return ret; +} + +/* + * Setup then Resume from the hibernate image using swsusp_arch_suspend_exit(). + * + * Memory allocated by get_safe_page() will be dealt with by the hibernate code, + * we don't need to free it here. + */ +int swsusp_arch_resume(void) +{ + int rc; + void *zero_page; + size_t exit_size; + pgd_t *tmp_pg_dir; + phys_addr_t el2_vectors; + void __noreturn (*hibernate_exit)(phys_addr_t, phys_addr_t, void *, + void *, phys_addr_t, phys_addr_t); + struct trans_pgd_info trans_info = { + .trans_alloc_page = hibernate_page_alloc, + .trans_alloc_arg = (void *)GFP_ATOMIC, + }; + + /* + * Restoring the memory image will overwrite the ttbr1 page tables. + * Create a second copy of just the linear map, and use this when + * restoring. + */ + rc = trans_pgd_create_copy(&trans_info, &tmp_pg_dir, PAGE_OFFSET, + PAGE_END); + if (rc) + return rc; + + /* + * We need a zero page that is zero before & after resume in order + * to break before make on the ttbr1 page tables. + */ + zero_page = (void *)get_safe_page(GFP_ATOMIC); + if (!zero_page) { + pr_err("Failed to allocate zero page.\n"); + return -ENOMEM; + } + + if (el2_reset_needed()) { + rc = trans_pgd_copy_el2_vectors(&trans_info, &el2_vectors); + if (rc) { + pr_err("Failed to setup el2 vectors\n"); + return rc; + } + } + + exit_size = __hibernate_exit_text_end - __hibernate_exit_text_start; + /* + * Copy swsusp_arch_suspend_exit() to a safe page. This will generate + * a new set of ttbr0 page tables and load them. + */ + rc = create_safe_exec_page(__hibernate_exit_text_start, exit_size, + (phys_addr_t *)&hibernate_exit); + if (rc) { + pr_err("Failed to create safe executable page for hibernate_exit code.\n"); + return rc; + } + + /* + * KASLR will cause the el2 vectors to be in a different location in + * the resumed kernel. Load hibernate's temporary copy into el2. + * + * We can skip this step if we booted at EL1, or are running with VHE. + */ + if (el2_reset_needed()) + __hyp_set_vectors(el2_vectors); + + hibernate_exit(virt_to_phys(tmp_pg_dir), resume_hdr.ttbr1_el1, + resume_hdr.reenter_kernel, restore_pblist, + resume_hdr.__hyp_stub_vectors, virt_to_phys(zero_page)); + + return 0; +} + +int hibernate_resume_nonboot_cpu_disable(void) +{ + if (sleep_cpu < 0) { + pr_err("Failing to resume from hibernate on an unknown CPU.\n"); + return -ENODEV; + } + + return freeze_secondary_cpus(sleep_cpu); +} |