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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 /tools/testing/selftests/powerpc/tm/tm-signal-pagefault.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 'tools/testing/selftests/powerpc/tm/tm-signal-pagefault.c')
-rw-r--r-- | tools/testing/selftests/powerpc/tm/tm-signal-pagefault.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/tm/tm-signal-pagefault.c b/tools/testing/selftests/powerpc/tm/tm-signal-pagefault.c new file mode 100644 index 000000000..0b84c9208 --- /dev/null +++ b/tools/testing/selftests/powerpc/tm/tm-signal-pagefault.c @@ -0,0 +1,285 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2020, Gustavo Luiz Duarte, IBM Corp. + * + * This test starts a transaction and triggers a signal, forcing a pagefault to + * happen when the kernel signal handling code touches the user signal stack. + * + * In order to avoid pre-faulting the signal stack memory and to force the + * pagefault to happen precisely in the kernel signal handling code, the + * pagefault handling is done in userspace using the userfaultfd facility. + * + * Further pagefaults are triggered by crafting the signal handler's ucontext + * to point to additional memory regions managed by the userfaultfd, so using + * the same mechanism used to avoid pre-faulting the signal stack memory. + * + * On failure (bug is present) kernel crashes or never returns control back to + * userspace. If bug is not present, tests completes almost immediately. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <linux/userfaultfd.h> +#include <poll.h> +#include <unistd.h> +#include <sys/ioctl.h> +#include <sys/syscall.h> +#include <fcntl.h> +#include <sys/mman.h> +#include <pthread.h> +#include <signal.h> +#include <errno.h> + +#include "tm.h" + + +#define UF_MEM_SIZE 655360 /* 10 x 64k pages */ + +/* Memory handled by userfaultfd */ +static char *uf_mem; +static size_t uf_mem_offset = 0; + +/* + * Data that will be copied into the faulting pages (instead of zero-filled + * pages). This is used to make the test more reliable and avoid segfaulting + * when we return from the signal handler. Since we are making the signal + * handler's ucontext point to newly allocated memory, when that memory is + * paged-in it will contain the expected content. + */ +static char backing_mem[UF_MEM_SIZE]; + +static size_t pagesize; + +/* + * Return a chunk of at least 'size' bytes of memory that will be handled by + * userfaultfd. If 'backing_data' is not NULL, its content will be save to + * 'backing_mem' and then copied into the faulting pages when the page fault + * is handled. + */ +void *get_uf_mem(size_t size, void *backing_data) +{ + void *ret; + + if (uf_mem_offset + size > UF_MEM_SIZE) { + fprintf(stderr, "Requesting more uf_mem than expected!\n"); + exit(EXIT_FAILURE); + } + + ret = &uf_mem[uf_mem_offset]; + + /* Save the data that will be copied into the faulting page */ + if (backing_data != NULL) + memcpy(&backing_mem[uf_mem_offset], backing_data, size); + + /* Reserve the requested amount of uf_mem */ + uf_mem_offset += size; + /* Keep uf_mem_offset aligned to the page size (round up) */ + uf_mem_offset = (uf_mem_offset + pagesize - 1) & ~(pagesize - 1); + + return ret; +} + +void *fault_handler_thread(void *arg) +{ + struct uffd_msg msg; /* Data read from userfaultfd */ + long uffd; /* userfaultfd file descriptor */ + struct uffdio_copy uffdio_copy; + struct pollfd pollfd; + ssize_t nread, offset; + + uffd = (long) arg; + + for (;;) { + pollfd.fd = uffd; + pollfd.events = POLLIN; + if (poll(&pollfd, 1, -1) == -1) { + perror("poll() failed"); + exit(EXIT_FAILURE); + } + + nread = read(uffd, &msg, sizeof(msg)); + if (nread == 0) { + fprintf(stderr, "read(): EOF on userfaultfd\n"); + exit(EXIT_FAILURE); + } + + if (nread == -1) { + perror("read() failed"); + exit(EXIT_FAILURE); + } + + /* We expect only one kind of event */ + if (msg.event != UFFD_EVENT_PAGEFAULT) { + fprintf(stderr, "Unexpected event on userfaultfd\n"); + exit(EXIT_FAILURE); + } + + /* + * We need to handle page faults in units of pages(!). + * So, round faulting address down to page boundary. + */ + uffdio_copy.dst = msg.arg.pagefault.address & ~(pagesize-1); + + offset = (char *) uffdio_copy.dst - uf_mem; + uffdio_copy.src = (unsigned long) &backing_mem[offset]; + + uffdio_copy.len = pagesize; + uffdio_copy.mode = 0; + uffdio_copy.copy = 0; + if (ioctl(uffd, UFFDIO_COPY, &uffdio_copy) == -1) { + perror("ioctl-UFFDIO_COPY failed"); + exit(EXIT_FAILURE); + } + } +} + +void setup_uf_mem(void) +{ + long uffd; /* userfaultfd file descriptor */ + pthread_t thr; + struct uffdio_api uffdio_api; + struct uffdio_register uffdio_register; + int ret; + + pagesize = sysconf(_SC_PAGE_SIZE); + + /* Create and enable userfaultfd object */ + uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + if (uffd == -1) { + perror("userfaultfd() failed"); + exit(EXIT_FAILURE); + } + uffdio_api.api = UFFD_API; + uffdio_api.features = 0; + if (ioctl(uffd, UFFDIO_API, &uffdio_api) == -1) { + perror("ioctl-UFFDIO_API failed"); + exit(EXIT_FAILURE); + } + + /* + * Create a private anonymous mapping. The memory will be demand-zero + * paged, that is, not yet allocated. When we actually touch the memory + * the related page will be allocated via the userfaultfd mechanism. + */ + uf_mem = mmap(NULL, UF_MEM_SIZE, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (uf_mem == MAP_FAILED) { + perror("mmap() failed"); + exit(EXIT_FAILURE); + } + + /* + * Register the memory range of the mapping we've just mapped to be + * handled by the userfaultfd object. In 'mode' we request to track + * missing pages (i.e. pages that have not yet been faulted-in). + */ + uffdio_register.range.start = (unsigned long) uf_mem; + uffdio_register.range.len = UF_MEM_SIZE; + uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING; + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1) { + perror("ioctl-UFFDIO_REGISTER"); + exit(EXIT_FAILURE); + } + + /* Create a thread that will process the userfaultfd events */ + ret = pthread_create(&thr, NULL, fault_handler_thread, (void *) uffd); + if (ret != 0) { + fprintf(stderr, "pthread_create(): Error. Returned %d\n", ret); + exit(EXIT_FAILURE); + } +} + +/* + * Assumption: the signal was delivered while userspace was in transactional or + * suspended state, i.e. uc->uc_link != NULL. + */ +void signal_handler(int signo, siginfo_t *si, void *uc) +{ + ucontext_t *ucp = uc; + + /* Skip 'trap' after returning, otherwise we get a SIGTRAP again */ + ucp->uc_link->uc_mcontext.regs->nip += 4; + + ucp->uc_mcontext.v_regs = + get_uf_mem(sizeof(elf_vrreg_t), ucp->uc_mcontext.v_regs); + + ucp->uc_link->uc_mcontext.v_regs = + get_uf_mem(sizeof(elf_vrreg_t), ucp->uc_link->uc_mcontext.v_regs); + + ucp->uc_link = get_uf_mem(sizeof(ucontext_t), ucp->uc_link); +} + +bool have_userfaultfd(void) +{ + long rc; + + errno = 0; + rc = syscall(__NR_userfaultfd, -1); + + return rc == 0 || errno != ENOSYS; +} + +int tm_signal_pagefault(void) +{ + struct sigaction sa; + stack_t ss; + + SKIP_IF(!have_htm()); + SKIP_IF(htm_is_synthetic()); + SKIP_IF(!have_userfaultfd()); + + setup_uf_mem(); + + /* + * Set an alternative stack that will generate a page fault when the + * signal is raised. The page fault will be treated via userfaultfd, + * i.e. via fault_handler_thread. + */ + ss.ss_sp = get_uf_mem(SIGSTKSZ, NULL); + ss.ss_size = SIGSTKSZ; + ss.ss_flags = 0; + if (sigaltstack(&ss, NULL) == -1) { + perror("sigaltstack() failed"); + exit(EXIT_FAILURE); + } + + sa.sa_flags = SA_SIGINFO | SA_ONSTACK; + sa.sa_sigaction = signal_handler; + if (sigaction(SIGTRAP, &sa, NULL) == -1) { + perror("sigaction() failed"); + exit(EXIT_FAILURE); + } + + /* Trigger a SIGTRAP in transactional state */ + asm __volatile__( + "tbegin.;" + "beq 1f;" + "trap;" + "1: ;" + : : : "memory"); + + /* Trigger a SIGTRAP in suspended state */ + asm __volatile__( + "tbegin.;" + "beq 1f;" + "tsuspend.;" + "trap;" + "tresume.;" + "1: ;" + : : : "memory"); + + return EXIT_SUCCESS; +} + +int main(int argc, char **argv) +{ + /* + * Depending on kernel config, the TM Bad Thing might not result in a + * crash, instead the kernel never returns control back to userspace, so + * set a tight timeout. If the test passes it completes almost + * immediately. + */ + test_harness_set_timeout(2); + return test_harness(tm_signal_pagefault, "tm_signal_pagefault"); +} |