Commit Graph

144 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
ec1a28c7c0 Merge 5.15.35 into android13-5.15
Changes in 5.15.35
	drm/amd/display: Add pstate verification and recovery for DCN31
	drm/amd/display: Fix p-state allow debug index on dcn31
	hamradio: defer 6pack kfree after unregister_netdev
	hamradio: remove needs_free_netdev to avoid UAF
	cpuidle: PSCI: Move the `has_lpi` check to the beginning of the function
	ACPI: processor idle: Check for architectural support for LPI
	ACPI: processor idle: Allow playing dead in C3 state
	ACPI: processor: idle: fix lockup regression on 32-bit ThinkPad T40
	btrfs: remove unused parameter nr_pages in add_ra_bio_pages()
	btrfs: remove no longer used counter when reading data page
	btrfs: remove unused variable in btrfs_{start,write}_dirty_block_groups()
	soc: qcom: aoss: Expose send for generic usecase
	dt-bindings: net: qcom,ipa: add optional qcom,qmp property
	net: ipa: request IPA register values be retained
	btrfs: release correct delalloc amount in direct IO write path
	ALSA: core: Add snd_card_free_on_error() helper
	ALSA: sis7019: Fix the missing error handling
	ALSA: ali5451: Fix the missing snd_card_free() call at probe error
	ALSA: als300: Fix the missing snd_card_free() call at probe error
	ALSA: als4000: Fix the missing snd_card_free() call at probe error
	ALSA: atiixp: Fix the missing snd_card_free() call at probe error
	ALSA: au88x0: Fix the missing snd_card_free() call at probe error
	ALSA: aw2: Fix the missing snd_card_free() call at probe error
	ALSA: azt3328: Fix the missing snd_card_free() call at probe error
	ALSA: bt87x: Fix the missing snd_card_free() call at probe error
	ALSA: ca0106: Fix the missing snd_card_free() call at probe error
	ALSA: cmipci: Fix the missing snd_card_free() call at probe error
	ALSA: cs4281: Fix the missing snd_card_free() call at probe error
	ALSA: cs5535audio: Fix the missing snd_card_free() call at probe error
	ALSA: echoaudio: Fix the missing snd_card_free() call at probe error
	ALSA: emu10k1x: Fix the missing snd_card_free() call at probe error
	ALSA: ens137x: Fix the missing snd_card_free() call at probe error
	ALSA: es1938: Fix the missing snd_card_free() call at probe error
	ALSA: es1968: Fix the missing snd_card_free() call at probe error
	ALSA: fm801: Fix the missing snd_card_free() call at probe error
	ALSA: galaxy: Fix the missing snd_card_free() call at probe error
	ALSA: hdsp: Fix the missing snd_card_free() call at probe error
	ALSA: hdspm: Fix the missing snd_card_free() call at probe error
	ALSA: ice1724: Fix the missing snd_card_free() call at probe error
	ALSA: intel8x0: Fix the missing snd_card_free() call at probe error
	ALSA: intel_hdmi: Fix the missing snd_card_free() call at probe error
	ALSA: korg1212: Fix the missing snd_card_free() call at probe error
	ALSA: lola: Fix the missing snd_card_free() call at probe error
	ALSA: lx6464es: Fix the missing snd_card_free() call at probe error
	ALSA: maestro3: Fix the missing snd_card_free() call at probe error
	ALSA: oxygen: Fix the missing snd_card_free() call at probe error
	ALSA: riptide: Fix the missing snd_card_free() call at probe error
	ALSA: rme32: Fix the missing snd_card_free() call at probe error
	ALSA: rme9652: Fix the missing snd_card_free() call at probe error
	ALSA: rme96: Fix the missing snd_card_free() call at probe error
	ALSA: sc6000: Fix the missing snd_card_free() call at probe error
	ALSA: sonicvibes: Fix the missing snd_card_free() call at probe error
	ALSA: via82xx: Fix the missing snd_card_free() call at probe error
	ALSA: usb-audio: Cap upper limits of buffer/period bytes for implicit fb
	ALSA: nm256: Don't call card private_free at probe error path
	drm/msm: Add missing put_task_struct() in debugfs path
	firmware: arm_scmi: Remove clear channel call on the TX channel
	memory: atmel-ebi: Fix missing of_node_put in atmel_ebi_probe
	Revert "ath11k: mesh: add support for 256 bitmap in blockack frames in 11ax"
	firmware: arm_scmi: Fix sorting of retrieved clock rates
	media: rockchip/rga: do proper error checking in probe
	SUNRPC: Fix the svc_deferred_event trace class
	net/sched: flower: fix parsing of ethertype following VLAN header
	veth: Ensure eth header is in skb's linear part
	gpiolib: acpi: use correct format characters
	cifs: release cached dentries only if mount is complete
	net: mdio: don't defer probe forever if PHY IRQ provider is missing
	mlxsw: i2c: Fix initialization error flow
	net/sched: fix initialization order when updating chain 0 head
	net: dsa: felix: suppress -EPROBE_DEFER errors
	net: ethernet: stmmac: fix altr_tse_pcs function when using a fixed-link
	net/sched: taprio: Check if socket flags are valid
	cfg80211: hold bss_lock while updating nontrans_list
	netfilter: nft_socket: make cgroup match work in input too
	drm/msm: Fix range size vs end confusion
	drm/msm/dsi: Use connector directly in msm_dsi_manager_connector_init()
	drm/msm/dp: add fail safe mode outside of event_mutex context
	net/smc: Fix NULL pointer dereference in smc_pnet_find_ib()
	scsi: pm80xx: Mask and unmask upper interrupt vectors 32-63
	scsi: pm80xx: Enable upper inbound, outbound queues
	scsi: iscsi: Move iscsi_ep_disconnect()
	scsi: iscsi: Fix offload conn cleanup when iscsid restarts
	scsi: iscsi: Fix endpoint reuse regression
	scsi: iscsi: Fix conn cleanup and stop race during iscsid restart
	scsi: iscsi: Fix unbound endpoint error handling
	sctp: Initialize daddr on peeled off socket
	netfilter: nf_tables: nft_parse_register can return a negative value
	ALSA: ad1889: Fix the missing snd_card_free() call at probe error
	ALSA: mtpav: Don't call card private_free at probe error path
	io_uring: move io_uring_rsrc_update2 validation
	io_uring: verify that resv2 is 0 in io_uring_rsrc_update2
	io_uring: verify pad field is 0 in io_get_ext_arg
	testing/selftests/mqueue: Fix mq_perf_tests to free the allocated cpu set
	ALSA: usb-audio: Increase max buffer size
	ALSA: usb-audio: Limit max buffer and period sizes per time
	perf tools: Fix misleading add event PMU debug message
	macvlan: Fix leaking skb in source mode with nodst option
	net: ftgmac100: access hardware register after clock ready
	nfc: nci: add flush_workqueue to prevent uaf
	cifs: potential buffer overflow in handling symlinks
	dm mpath: only use ktime_get_ns() in historical selector
	vfio/pci: Fix vf_token mechanism when device-specific VF drivers are used
	net: bcmgenet: Revert "Use stronger register read/writes to assure ordering"
	block: fix offset/size check in bio_trim()
	drm/amd: Add USBC connector ID
	btrfs: fix fallocate to use file_modified to update permissions consistently
	btrfs: do not warn for free space inode in cow_file_range
	drm/amdgpu: conduct a proper cleanup of PDB bo
	drm/amdgpu/gmc: use PCI BARs for APUs in passthrough
	drm/amd/display: fix audio format not updated after edid updated
	drm/amd/display: FEC check in timing validation
	drm/amd/display: Update VTEM Infopacket definition
	drm/amdkfd: Fix Incorrect VMIDs passed to HWS
	drm/amdgpu/vcn: improve vcn dpg stop procedure
	drm/amdkfd: Check for potential null return of kmalloc_array()
	Drivers: hv: vmbus: Deactivate sysctl_record_panic_msg by default in isolated guests
	PCI: hv: Propagate coherence from VMbus device to PCI device
	Drivers: hv: vmbus: Prevent load re-ordering when reading ring buffer
	scsi: target: tcmu: Fix possible page UAF
	scsi: lpfc: Fix queue failures when recovering from PCI parity error
	scsi: ibmvscsis: Increase INITIAL_SRP_LIMIT to 1024
	net: micrel: fix KS8851_MLL Kconfig
	ata: libata-core: Disable READ LOG DMA EXT for Samsung 840 EVOs
	gpu: ipu-v3: Fix dev_dbg frequency output
	regulator: wm8994: Add an off-on delay for WM8994 variant
	arm64: alternatives: mark patch_alternative() as `noinstr`
	tlb: hugetlb: Add more sizes to tlb_remove_huge_tlb_entry
	net: axienet: setup mdio unconditionally
	Drivers: hv: balloon: Disable balloon and hot-add accordingly
	net: usb: aqc111: Fix out-of-bounds accesses in RX fixup
	myri10ge: fix an incorrect free for skb in myri10ge_sw_tso
	spi: cadence-quadspi: fix protocol setup for non-1-1-X operations
	drm/amd/display: Enable power gating before init_pipes
	drm/amd/display: Revert FEC check in validation
	drm/amd/display: Fix allocate_mst_payload assert on resume
	drbd: set QUEUE_FLAG_STABLE_WRITES
	scsi: mpt3sas: Fail reset operation if config request timed out
	scsi: mvsas: Add PCI ID of RocketRaid 2640
	scsi: megaraid_sas: Target with invalid LUN ID is deleted during scan
	drivers: net: slip: fix NPD bug in sl_tx_timeout()
	io_uring: zero tag on rsrc removal
	io_uring: use nospec annotation for more indexes
	perf/imx_ddr: Fix undefined behavior due to shift overflowing the constant
	mm/secretmem: fix panic when growing a memfd_secret
	mm, page_alloc: fix build_zonerefs_node()
	mm: fix unexpected zeroed page mapping with zram swap
	mm: kmemleak: take a full lowmem check in kmemleak_*_phys()
	KVM: x86/mmu: Resolve nx_huge_pages when kvm.ko is loaded
	SUNRPC: Fix NFSD's request deferral on RDMA transports
	memory: renesas-rpc-if: fix platform-device leak in error path
	gcc-plugins: latent_entropy: use /dev/urandom
	cifs: verify that tcon is valid before dereference in cifs_kill_sb
	ath9k: Properly clear TX status area before reporting to mac80211
	ath9k: Fix usage of driver-private space in tx_info
	btrfs: fix root ref counts in error handling in btrfs_get_root_ref
	btrfs: mark resumed async balance as writing
	ALSA: hda/realtek: Add quirk for Clevo PD50PNT
	ALSA: hda/realtek: add quirk for Lenovo Thinkpad X12 speakers
	ALSA: pcm: Test for "silence" field in struct "pcm_format_data"
	nl80211: correctly check NL80211_ATTR_REG_ALPHA2 size
	ipv6: fix panic when forwarding a pkt with no in6 dev
	drm/amd/display: don't ignore alpha property on pre-multiplied mode
	drm/amdgpu: Enable gfxoff quirk on MacBook Pro
	x86/tsx: Use MSR_TSX_CTRL to clear CPUID bits
	x86/tsx: Disable TSX development mode at boot
	genirq/affinity: Consider that CPUs on nodes can be unbalanced
	tick/nohz: Use WARN_ON_ONCE() to prevent console saturation
	ARM: davinci: da850-evm: Avoid NULL pointer dereference
	dm integrity: fix memory corruption when tag_size is less than digest size
	i2c: dev: check return value when calling dev_set_name()
	smp: Fix offline cpu check in flush_smp_call_function_queue()
	i2c: pasemi: Wait for write xfers to finish
	dt-bindings: net: snps: remove duplicate name
	timers: Fix warning condition in __run_timers()
	dma-direct: avoid redundant memory sync for swiotlb
	drm/i915: Sunset igpu legacy mmap support based on GRAPHICS_VER_FULL
	cpu/hotplug: Remove the 'cpu' member of cpuhp_cpu_state
	soc: qcom: aoss: Fix missing put_device call in qmp_get
	net: ipa: fix a build dependency
	cpufreq: intel_pstate: ITMT support for overclocked system
	ax25: add refcount in ax25_dev to avoid UAF bugs
	ax25: fix reference count leaks of ax25_dev
	ax25: fix UAF bugs of net_device caused by rebinding operation
	ax25: Fix refcount leaks caused by ax25_cb_del()
	ax25: fix UAF bug in ax25_send_control()
	ax25: fix NPD bug in ax25_disconnect
	ax25: Fix NULL pointer dereferences in ax25 timers
	ax25: Fix UAF bugs in ax25 timers
	Linux 5.15.35

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I0dd9eaea7f977df42b0a5b9cb9043c879f62718b
2022-04-24 16:58:59 +02:00
Anna-Maria Behnsen
111becd63e timers: Fix warning condition in __run_timers()
commit c54bc0fc84214b203f7a0ebfd1bd308ce2abe920 upstream.

When the timer base is empty, base::next_expiry is set to base::clk +
NEXT_TIMER_MAX_DELTA and base::next_expiry_recalc is false. When no timer
is queued until jiffies reaches base::next_expiry value, the warning for
not finding any expired timer and base::next_expiry_recalc is false in
__run_timers() triggers.

To prevent triggering the warning in this valid scenario
base::timers_pending needs to be added to the warning condition.

Fixes: 31cd0e119d ("timers: Recalculate next timer interrupt only when necessary")
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20220405191732.7438-3-anna-maria@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-20 09:34:21 +02:00
Prasad Sodagudi
b1315d6275 ANDROID: timer: update vendor hook for timer calc index
commit '18550710107d ANDROID: timer: Add vendor hook for timer calc index'
is changing the expires value only for bucket calculation, so timer
wont be very precise in this case.

Bug: 178758017
Change-Id: I8218a4065d31ed60bafdbbb36c1d6d9c9f0a6e9e
Signed-off-by: Prasad Sodagudi <quic_psodagud@quicinc.com>
Signed-off-by: Gokul krishna Krishnakumar <quic_gokukris@quicinc.com>
2022-03-24 22:02:34 +00:00
Greg Kroah-Hartman
1dcc7190fe Merge 5.15.8 into android13-5.15
Changes in 5.15.8
	usb: gadget: uvc: fix multiple opens
	HID: quirks: Add quirk for the Microsoft Surface 3 type-cover
	HID: google: add eel USB id
	HID: intel-ish-hid: ipc: only enable IRQ wakeup when requested
	HID: add hid_is_usb() function to make it simpler for USB detection
	HID: add USB_HID dependancy to hid-prodikeys
	HID: add USB_HID dependancy to hid-chicony
	HID: add USB_HID dependancy on some USB HID drivers
	HID: bigbenff: prevent null pointer dereference
	HID: wacom: fix problems when device is not a valid USB device
	HID: check for valid USB device for many HID drivers
	mtd: dataflash: Add device-tree SPI IDs
	mmc: spi: Add device-tree SPI IDs
	HID: sony: fix error path in probe
	HID: Ignore battery for Elan touchscreen on Asus UX550VE
	platform/x86/intel: hid: add quirk to support Surface Go 3
	nft_set_pipapo: Fix bucket load in AVX2 lookup routine for six 8-bit groups
	IB/hfi1: Insure use of smp_processor_id() is preempt disabled
	IB/hfi1: Fix early init panic
	IB/hfi1: Fix leak of rcvhdrtail_dummy_kvaddr
	can: kvaser_usb: get CAN clock frequency from device
	can: kvaser_pciefd: kvaser_pciefd_rx_error_frame(): increase correct stats->{rx,tx}_errors counter
	can: sja1000: fix use after free in ems_pcmcia_add_card()
	can: pch_can: pch_can_rx_normal: fix use after free
	can: m_can: m_can_read_fifo: fix memory leak in error branch
	can: m_can: pci: fix incorrect reference clock rate
	can: m_can: pci: fix iomap_read_fifo() and iomap_write_fifo()
	can: m_can: Disable and ignore ELO interrupt
	net: dsa: mv88e6xxx: fix "don't use PHY_DETECT on internal PHY's"
	net: dsa: mv88e6xxx: allow use of PHYs on CPU and DSA ports
	x86/sme: Explicitly map new EFI memmap table as encrypted
	platform/x86: amd-pmc: Fix s2idle failures on certain AMD laptops
	nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
	selftests: netfilter: add a vrf+conntrack testcase
	vrf: don't run conntrack on vrf with !dflt qdisc
	bpf, x86: Fix "no previous prototype" warning
	bpf, sockmap: Attach map progs to psock early for feature probes
	bpf: Make sure bpf_disable_instrumentation() is safe vs preemption.
	bpf: Fix the off-by-two error in range markings
	ice: ignore dropped packets during init
	ethtool: do not perform operations on net devices being unregistered
	bonding: make tx_rebalance_counter an atomic
	nfp: Fix memory leak in nfp_cpp_area_cache_add()
	seg6: fix the iif in the IPv6 socket control block
	udp: using datalen to cap max gso segments
	netfilter: nft_exthdr: break evaluation if setting TCP option fails
	netfilter: conntrack: annotate data-races around ct->timeout
	iavf: restore MSI state on reset
	iavf: Fix reporting when setting descriptor count
	IB/hfi1: Correct guard on eager buffer deallocation
	devlink: fix netns refcount leak in devlink_nl_cmd_reload()
	net: bcm4908: Handle dma_set_coherent_mask error codes
	net: dsa: mv88e6xxx: error handling for serdes_power functions
	net: dsa: felix: Fix memory leak in felix_setup_mmio_filtering
	net/sched: fq_pie: prevent dismantle issue
	net: mvpp2: fix XDP rx queues registering
	KVM: x86: Don't WARN if userspace mucks with RCX during string I/O exit
	KVM: x86: Ignore sparse banks size for an "all CPUs", non-sparse IPI req
	KVM: x86: Wait for IPIs to be delivered when handling Hyper-V TLB flush hypercall
	timers: implement usleep_idle_range()
	mm/damon/core: fix fake load reports due to uninterruptible sleeps
	mm/slub: fix endianness bug for alloc/free_traces attributes
	mm: bdi: initialize bdi_min_ratio when bdi is unregistered
	ALSA: ctl: Fix copy of updated id with element read/write
	ALSA: hda/realtek - Add headset Mic support for Lenovo ALC897 platform
	ALSA: hda/realtek: Fix quirk for TongFang PHxTxX1
	ALSA: pcm: oss: Fix negative period/buffer sizes
	ALSA: pcm: oss: Limit the period size to 16MB
	ALSA: pcm: oss: Handle missing errors in snd_pcm_oss_change_params*()
	cifs: Fix crash on unload of cifs_arc4.ko
	scsi: qla2xxx: Format log strings only if needed
	btrfs: clear extent buffer uptodate when we fail to write it
	btrfs: fix re-dirty process of tree-log nodes
	btrfs: replace the BUG_ON in btrfs_del_root_ref with proper error handling
	btrfs: free exchange changeset on failures
	perf intel-pt: Fix some PGE (packet generation enable/control flow packets) usage
	perf intel-pt: Fix sync state when a PSB (synchronization) packet is found
	perf intel-pt: Fix intel_pt_fup_event() assumptions about setting state type
	perf intel-pt: Fix state setting when receiving overflow (OVF) packet
	perf intel-pt: Fix next 'err' value, walking trace
	perf intel-pt: Fix missing 'instruction' events with 'q' option
	perf intel-pt: Fix error timestamp setting on the decoder error path
	md: fix update super 1.0 on rdev size change
	nfsd: fix use-after-free due to delegation race
	nfsd: Fix nsfd startup race (again)
	tracefs: Have new files inherit the ownership of their parent
	selftests: KVM: avoid failures due to reserved HyperTransport region
	hwmon: (pwm-fan) Ensure the fan going on in .probe()
	mmc: renesas_sdhi: initialize variable properly when tuning
	clk: qcom: regmap-mux: fix parent clock lookup
	thermal: int340x: Fix VCoRefLow MMIO bit offset for TGL
	drm/syncobj: Deal with signalled fences in drm_syncobj_find_fence.
	libata: add horkage for ASMedia 1092
	io_uring: ensure task_work gets run as part of cancelations
	wait: add wake_up_pollfree()
	binder: use wake_up_pollfree()
	signalfd: use wake_up_pollfree()
	aio: keep poll requests on waitqueue until completed
	aio: fix use-after-free due to missing POLLFREE handling
	tracefs: Set all files to the same group ownership as the mount option
	i2c: mpc: Use atomic read and fix break condition
	block: fix ioprio_get(IOPRIO_WHO_PGRP) vs setuid(2)
	scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc()
	scsi: scsi_debug: Fix buffer size of REPORT ZONES command
	ALSA: usb-audio: Reorder snd_djm_devices[] entries
	qede: validate non LSO skb length
	PM: runtime: Fix pm_runtime_active() kerneldoc comment
	ASoC: rt5682: Fix crash due to out of scope stack vars
	ASoC: qdsp6: q6routing: Fix return value from msm_routing_put_audio_mixer
	ASoC: codecs: wsa881x: fix return values from kcontrol put
	ASoC: codecs: wcd934x: handle channel mappping list correctly
	ASoC: codecs: wcd934x: return correct value from mixer put
	RDMA/hns: Do not halt commands during reset until later
	RDMA/hns: Do not destroy QP resources in the hw resetting phase
	hwmon: (dell-smm) Fix warning on /proc/i8k creation error
	clk: imx: use module_platform_driver
	clk: qcom: clk-alpha-pll: Don't reconfigure running Trion
	i40e: Fix failed opcode appearing if handling messages from VF
	i40e: Fix pre-set max number of queues for VF
	mtd: rawnand: fsmc: Take instruction delay into account
	mtd: rawnand: fsmc: Fix timing computation
	bpf, sockmap: Re-evaluate proto ops when psock is removed from sockmap
	i40e: Fix NULL pointer dereference in i40e_dbg_dump_desc
	Revert "PCI: aardvark: Fix support for PCI_ROM_ADDRESS1 on emulated bridge"
	drm/amd/display: Fix DPIA outbox timeout after S3/S4/reset
	perf tools: Fix SMT detection fast read path
	Documentation/locking/locktypes: Update migrate_disable() bits.
	dt-bindings: net: Reintroduce PHY no lane swap binding
	tools build: Remove needless libpython-version feature check that breaks test-all fast path
	net: cdc_ncm: Allow for dwNtbOutMaxSize to be unset or zero
	net: altera: set a couple error code in probe()
	net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()
	net, neigh: clear whole pneigh_entry at alloc time
	net/qla3xxx: fix an error code in ql_adapter_up()
	selftests/fib_tests: Rework fib_rp_filter_test()
	USB: gadget: detect too-big endpoint 0 requests
	USB: gadget: zero allocate endpoint 0 buffers
	Revert "usb: dwc3: dwc3-qcom: Enable tx-fifo-resize property by default"
	usb: core: config: fix validation of wMaxPacketValue entries
	xhci: Remove CONFIG_USB_DEFAULT_PERSIST to prevent xHCI from runtime suspending
	usb: core: config: using bit mask instead of individual bits
	xhci: avoid race between disable slot command and host runtime suspend
	iio: gyro: adxrs290: fix data signedness
	iio: trigger: Fix reference counting
	iio: trigger: stm32-timer: fix MODULE_ALIAS
	iio: stk3310: Don't return error code in interrupt handler
	iio: mma8452: Fix trigger reference couting
	iio: ltr501: Don't return error code in trigger handler
	iio: kxsd9: Don't return error code in trigger handler
	iio: itg3200: Call iio_trigger_notify_done() on error
	iio: dln2-adc: Fix lockdep complaint
	iio: dln2: Check return value of devm_iio_trigger_register()
	iio: at91-sama5d2: Fix incorrect sign extension
	iio: adc: stm32: fix a current leak by resetting pcsel before disabling vdda
	iio: adc: axp20x_adc: fix charging current reporting on AXP22x
	iio: ad7768-1: Call iio_trigger_notify_done() on error
	iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove
	misc: rtsx: Avoid mangling IRQ during runtime PM
	nvmem: eeprom: at25: fix FRAM byte_len
	bus: mhi: pci_generic: Fix device recovery failed issue
	bus: mhi: core: Add support for forced PM resume
	csky: fix typo of fpu config macro
	irqchip/aspeed-scu: Replace update_bits with write_bits.
	irqchip/armada-370-xp: Fix return value of armada_370_xp_msi_alloc()
	irqchip/armada-370-xp: Fix support for Multi-MSI interrupts
	aio: Fix incorrect usage of eventfd_signal_allowed()
	irqchip/irq-gic-v3-its.c: Force synchronisation when issuing INVALL
	irqchip: nvic: Fix offset for Interrupt Priority Offsets
	misc: fastrpc: fix improper packet size calculation
	clocksource/drivers/dw_apb_timer_of: Fix probe failure
	bpf: Add selftests to cover packet access corner cases
	Linux 5.15.8

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I4d543d6826c20e322ce477fe82c462791dc36ce4
2021-12-15 18:34:21 +01:00
SeongJae Park
5a960e533c timers: implement usleep_idle_range()
commit e4779015fd5d2fb8390c258268addff24d6077c7 upstream.

Patch series "mm/damon: Fix fake /proc/loadavg reports", v3.

This patchset fixes DAMON's fake load report issue.  The first patch
makes yet another variant of usleep_range() for this fix, and the second
patch fixes the issue of DAMON by making it using the newly introduced
function.

This patch (of 2):

Some kernel threads such as DAMON could need to repeatedly sleep in
micro seconds level.  Because usleep_range() sleeps in uninterruptible
state, however, such threads would make /proc/loadavg reports fake load.

To help such cases, this commit implements a variant of usleep_range()
called usleep_idle_range().  It is same to usleep_range() but sets the
state of the current task as TASK_IDLE while sleeping.

Link: https://lkml.kernel.org/r/20211126145015.15862-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20211126145015.15862-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: John Stultz <john.stultz@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-14 10:57:11 +01:00
Changki Kim
7dc223cb02 ANDROID: timer: Export hrtimer_expire_entry/exit tracepoints
Export hrtimer_expire_entry/exit tracepoints, so that vendor modules
can register probes for these tracepoints.

Bug: 205928005
Change-Id: I739f369d3b56e09f8e9061fefdf25830e37e987e
Signed-off-by: Changki Kim <changki.kim@samsung.com>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
2021-11-11 18:55:07 +00:00
Huang Yiwei
1855071010 ANDROID: timer: Add vendor hook for timer calc index
Since we're expecting timers more precisely in short period, add
a vendor hook to calc_index when adding timers. Then we can modify
the index this timer used to make it accurate.

Bug: 178758017
Signed-off-by: Huang Yiwei <hyiwei@codeaurora.org>
Change-Id: Ie0e6493ae7ad53b0cc57eb1bbcf8a0a11f652828
2021-08-12 15:13:23 -07:00
Thomas Gleixner
bb7262b295 timers: Move clearing of base::timer_running under base:: Lock
syzbot reported KCSAN data races vs. timer_base::timer_running being set to
NULL without holding base::lock in expire_timers().

This looks innocent and most reads are clearly not problematic, but
Frederic identified an issue which is:

 int data = 0;

 void timer_func(struct timer_list *t)
 {
    data = 1;
 }

 CPU 0                                            CPU 1
 ------------------------------                   --------------------------
 base = lock_timer_base(timer, &flags);           raw_spin_unlock(&base->lock);
 if (base->running_timer != timer)                call_timer_fn(timer, fn, baseclk);
   ret = detach_if_pending(timer, base, true);    base->running_timer = NULL;
 raw_spin_unlock_irqrestore(&base->lock, flags);  raw_spin_lock(&base->lock);

 x = data;

If the timer has previously executed on CPU 1 and then CPU 0 can observe
base->running_timer == NULL and returns, assuming the timer has completed,
but it's not guaranteed on all architectures. The comment for
del_timer_sync() makes that guarantee. Moving the assignment under
base->lock prevents this.

For non-RT kernel it's performance wise completely irrelevant whether the
store happens before or after taking the lock. For an RT kernel moving the
store under the lock requires an extra unlock/lock pair in the case that
there is a waiter for the timer, but that's not the end of the world.

Reported-by: syzbot+aa7c2385d46c5eba0b89@syzkaller.appspotmail.com
Reported-by: syzbot+abea4558531bae1ba9fe@syzkaller.appspotmail.com
Fixes: 030dcdd197 ("timers: Prepare support for PREEMPT_RT")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/87lfea7gw8.fsf@nanos.tec.linutronix.de
Cc: stable@vger.kernel.org
2021-07-27 20:57:44 +02:00
Nicolas Saenz Julienne
aebacb7f6c timers: Fix get_next_timer_interrupt() with no timers pending
31cd0e119d ("timers: Recalculate next timer interrupt only when
necessary") subtly altered get_next_timer_interrupt()'s behaviour. The
function no longer consistently returns KTIME_MAX with no timers
pending.

In order to decide if there are any timers pending we check whether the
next expiry will happen NEXT_TIMER_MAX_DELTA jiffies from now.
Unfortunately, the next expiry time and the timer base clock are no
longer updated in unison. The former changes upon certain timer
operations (enqueue, expire, detach), whereas the latter keeps track of
jiffies as they move forward. Ultimately breaking the logic above.

A simplified example:

- Upon entering get_next_timer_interrupt() with:

	jiffies = 1
	base->clk = 0;
	base->next_expiry = NEXT_TIMER_MAX_DELTA;

  'base->next_expiry == base->clk + NEXT_TIMER_MAX_DELTA', the function
  returns KTIME_MAX.

- 'base->clk' is updated to the jiffies value.

- The next time we enter get_next_timer_interrupt(), taking into account
  no timer operations happened:

	base->clk = 1;
	base->next_expiry = NEXT_TIMER_MAX_DELTA;

  'base->next_expiry != base->clk + NEXT_TIMER_MAX_DELTA', the function
  returns a valid expire time, which is incorrect.

This ultimately might unnecessarily rearm sched's timer on nohz_full
setups, and add latency to the system[1].

So, introduce 'base->timers_pending'[2], update it every time
'base->next_expiry' changes, and use it in get_next_timer_interrupt().

[1] See tick_nohz_stop_tick().
[2] A quick pahole check on x86_64 and arm64 shows it doesn't make
    'struct timer_base' any bigger.

Fixes: 31cd0e119d ("timers: Recalculate next timer interrupt only when necessary")
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
2021-07-15 01:23:54 +02:00
Linus Torvalds
28e92f9903 Merge branch 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull RCU updates from Paul McKenney:

 - Bitmap parsing support for "all" as an alias for all bits

 - Documentation updates

 - Miscellaneous fixes, including some that overlap into mm and lockdep

 - kvfree_rcu() updates

 - mem_dump_obj() updates, with acks from one of the slab-allocator
   maintainers

 - RCU NOCB CPU updates, including limited deoffloading

 - SRCU updates

 - Tasks-RCU updates

 - Torture-test updates

* 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (78 commits)
  tasks-rcu: Make show_rcu_tasks_gp_kthreads() be static inline
  rcu-tasks: Make ksoftirqd provide RCU Tasks quiescent states
  rcu: Add missing __releases() annotation
  rcu: Remove obsolete rcu_read_unlock() deadlock commentary
  rcu: Improve comments describing RCU read-side critical sections
  rcu: Create an unrcu_pointer() to remove __rcu from a pointer
  srcu: Early test SRCU polling start
  rcu: Fix various typos in comments
  rcu/nocb: Unify timers
  rcu/nocb: Prepare for fine-grained deferred wakeup
  rcu/nocb: Only cancel nocb timer if not polling
  rcu/nocb: Delete bypass_timer upon nocb_gp wakeup
  rcu/nocb: Cancel nocb_timer upon nocb_gp wakeup
  rcu/nocb: Allow de-offloading rdp leader
  rcu/nocb: Directly call __wake_nocb_gp() from bypass timer
  rcu: Don't penalize priority boosting when there is nothing to boost
  rcu: Point to documentation of ordering guarantees
  rcu: Make rcu_gp_cleanup() be noinline for tracing
  rcu: Restrict RCU_STRICT_GRACE_PERIOD to at most four CPUs
  rcu: Make show_rcu_gp_kthreads() dump rcu_node structures blocking GP
  ...
2021-07-04 12:58:33 -07:00
Peter Zijlstra
600642ae90 sched,timer: Use __set_current_state()
There's an existing helper for setting TASK_RUNNING; must've gotten
lost last time we did this cleanup.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210611082838.409696194@infradead.org
2021-06-18 11:43:08 +02:00
Frederic Weisbecker
258ca95e2c timer: Revert "timer: Add timer_curr_running()"
This reverts commit dcd42591eb.
The only user was RCU/nocb.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Neeraj Upadhyay <neeraju@codeaurora.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10 16:02:44 -07:00
Ingo Molnar
4bf07f6562 timekeeping, clocksource: Fix various typos in comments
Fix ~56 single-word typos in timekeeping & clocksource code comments.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-kernel@vger.kernel.org
2021-03-22 23:06:48 +01:00
Paul E. McKenney
f759081e8f rcu/nocb: Code-style nits in callback-offloading toggling
This commit addresses a few code-style nits in callback-offloading
toggling, including one that predates this toggling.

Cc: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-01-06 16:47:55 -08:00
Frederic Weisbecker
dcd42591eb timer: Add timer_curr_running()
This commit adds a timer_curr_running() function that verifies that the
current code is running in the context of the specified timer's handler.

Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Neeraj Upadhyay <neeraju@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-01-06 16:24:59 -08:00
Linus Torvalds
533369b145 Merge tag 'timers-core-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timers and timekeeping updates from Thomas Gleixner:
 "Core:

   - Robustness improvements for the NOHZ tick management

   - Fixes and consolidation of the NTP/RTC synchronization code

   - Small fixes and improvements in various places

   - A set of function documentation udpates and fixes

   Drivers:

   - Cleanups and improvements in various clocksoure/event drivers

   - Removal of the EZChip NPS clocksource driver as the platfrom
     support was removed from ARC

   - The usual set of new device tree binding and json conversions

   - The RTC driver which have been acked by the RTC maintainer:

       * fix a long standing bug in the MC146818 library code which can
         cause reading garbage during the RTC internal update.

       * changes related to the NTP/RTC consolidation work"

* tag 'timers-core-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  ntp: Fix prototype in the !CONFIG_GENERIC_CMOS_UPDATE case
  tick/sched: Make jiffies update quick check more robust
  ntp: Consolidate the RTC update implementation
  ntp: Make the RTC sync offset less obscure
  ntp, rtc: Move rtc_set_ntp_time() to ntp code
  ntp: Make the RTC synchronization more reliable
  rtc: core: Make the sync offset default more realistic
  rtc: cmos: Make rtc_cmos sync offset correct
  rtc: mc146818: Reduce spinlock section in mc146818_set_time()
  rtc: mc146818: Prevent reading garbage
  clocksource/drivers/sh_cmt: Fix potential deadlock when calling runtime PM
  clocksource/drivers/arm_arch_timer: Correct fault programming of CNTKCTL_EL1.EVNTI
  clocksource/drivers/arm_arch_timer: Use stable count reader in erratum sne
  clocksource/drivers/dw_apb_timer_of: Add error handling if no clock available
  clocksource/drivers/riscv: Make RISCV_TIMER depends on RISCV_SBI
  clocksource/drivers/ingenic: Fix section mismatch
  clocksource/drivers/cadence_ttc: Fix memory leak in ttc_setup_clockevent()
  dt-bindings: timer: renesas: tmu: Convert to json-schema
  dt-bindings: timer: renesas: tmu: Document r8a774e1 bindings
  clocksource/drivers/orion: Add missing clk_disable_unprepare() on error path
  ...
2020-12-14 18:21:14 -08:00
Thomas Gleixner
cc947f2b9c timers: Make run_local_timers() static
No users outside of the timer code. Move the caller below this function to
avoid a pointless forward declaration.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-11-16 15:20:01 +01:00
Sebastian Andrzej Siewior
c725dafc95 timers: Don't block on ->expiry_lock for TIMER_IRQSAFE timers
PREEMPT_RT does not spin and wait until a running timer completes its
callback but instead it blocks on a sleeping lock to prevent a livelock in
the case that the task waiting for the callback completion preempted the
callback.

This cannot be done for timers flagged with TIMER_IRQSAFE. These timers can
be canceled from an interrupt disabled context even on RT kernels.

The expiry callback of such timers is invoked with interrupts disabled so
there is no need to use the expiry lock mechanism because obviously the
callback cannot be preempted even on RT kernels.

Do not use the timer_base::expiry_lock mechanism when waiting for a running
callback to complete if the timer is flagged with TIMER_IRQSAFE.

Also add a lockdep assertion for RT kernels to validate that the expiry
lock mechanism is always invoked in preemptible context.

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201103190937.hga67rqhvknki3tp@linutronix.de
2020-11-15 20:59:26 +01:00
YueHaibing
9010e3876e timers: Remove unused inline funtion debug_timer_free()
There is no caller in tree, remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200909134749.32300-1-yuehaibing@huawei.com
2020-10-26 11:39:21 +01:00
Willy Tarreau
3744741ada random32: add noise from network and scheduling activity
With the removal of the interrupt perturbations in previous random32
change (random32: make prandom_u32() output unpredictable), the PRNG
has become 100% deterministic again. While SipHash is expected to be
way more robust against brute force than the previous Tausworthe LFSR,
there's still the risk that whoever has even one temporary access to
the PRNG's internal state is able to predict all subsequent draws till
the next reseed (roughly every minute). This may happen through a side
channel attack or any data leak.

This patch restores the spirit of commit f227e3ec3b ("random32: update
the net random state on interrupt and activity") in that it will perturb
the internal PRNG's statee using externally collected noise, except that
it will not pick that noise from the random pool's bits nor upon
interrupt, but will rather combine a few elements along the Tx path
that are collectively hard to predict, such as dev, skb and txq
pointers, packet length and jiffies values. These ones are combined
using a single round of SipHash into a single long variable that is
mixed with the net_rand_state upon each invocation.

The operation was inlined because it produces very small and efficient
code, typically 3 xor, 2 add and 2 rol. The performance was measured
to be the same (even very slightly better) than before the switch to
SipHash; on a 6-core 12-thread Core i7-8700k equipped with a 40G NIC
(i40e), the connection rate dropped from 556k/s to 555k/s while the
SYN cookie rate grew from 5.38 Mpps to 5.45 Mpps.

Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
Cc: George Spelvin <lkml@sdf.org>
Cc: Amit Klein <aksecurity@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tytso@mit.edu
Cc: Florian Westphal <fw@strlen.de>
Cc: Marc Plumb <lkml.mplumb@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2020-10-24 20:21:57 +02:00
George Spelvin
c51f8f88d7 random32: make prandom_u32() output unpredictable
Non-cryptographic PRNGs may have great statistical properties, but
are usually trivially predictable to someone who knows the algorithm,
given a small sample of their output.  An LFSR like prandom_u32() is
particularly simple, even if the sample is widely scattered bits.

It turns out the network stack uses prandom_u32() for some things like
random port numbers which it would prefer are *not* trivially predictable.
Predictability led to a practical DNS spoofing attack.  Oops.

This patch replaces the LFSR with a homebrew cryptographic PRNG based
on the SipHash round function, which is in turn seeded with 128 bits
of strong random key.  (The authors of SipHash have *not* been consulted
about this abuse of their algorithm.)  Speed is prioritized over security;
attacks are rare, while performance is always wanted.

Replacing all callers of prandom_u32() is the quick fix.
Whether to reinstate a weaker PRNG for uses which can tolerate it
is an open question.

Commit f227e3ec3b ("random32: update the net random state on interrupt
and activity") was an earlier attempt at a solution.  This patch replaces
it.

Reported-by: Amit Klein <aksecurity@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tytso@mit.edu
Cc: Florian Westphal <fw@strlen.de>
Cc: Marc Plumb <lkml.mplumb@gmail.com>
Fixes: f227e3ec3b ("random32: update the net random state on interrupt and activity")
Signed-off-by: George Spelvin <lkml@sdf.org>
Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
[ willy: partial reversal of f227e3ec3b5c; moved SIPROUND definitions
  to prandom.h for later use; merged George's prandom_seed() proposal;
  inlined siprand_u32(); replaced the net_rand_state[] array with 4
  members to fix a build issue; cosmetic cleanups to make checkpatch
  happy; fixed RANDOM32_SELFTEST build ]
Signed-off-by: Willy Tarreau <w@1wt.eu>
2020-10-24 20:21:57 +02:00
Linus Torvalds
f5f59336a9 Merge tag 'timers-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timekeeping updates from Thomas Gleixner:
 "Updates for timekeeping, timers and related drivers:

  Core:

   - Early boot support for the NMI safe timekeeper by utilizing
     local_clock() up to the point where timekeeping is initialized.
     This allows printk() to store multiple timestamps in the ringbuffer
     which is useful for coordinating dmesg information across a fleet
     of machines.

   - Provide a multi-timestamp accessor for printk()

   - Make timer init more robust by checking for invalid timer flags.

   - Comma vs semicolon fixes

  Drivers:

   - Support for new platforms in existing drivers (SP804 and Renesas
     CMT)

   - Comma vs semicolon fixes

* tag 'timers-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/armada-370-xp: Use semicolons rather than commas to separate statements
  clocksource/drivers/mps2-timer: Use semicolons rather than commas to separate statements
  timers: Mask invalid flags in do_init_timer()
  clocksource/drivers/sp804: Enable Hisilicon sp804 timer 64bit mode
  clocksource/drivers/sp804: Add support for Hisilicon sp804 timer
  clocksource/drivers/sp804: Support non-standard register offset
  clocksource/drivers/sp804: Prepare for support non-standard register offset
  clocksource/drivers/sp804: Remove a mismatched comment
  clocksource/drivers/sp804: Delete the leading "__" of some functions
  clocksource/drivers/sp804: Remove unused sp804_timer_disable() and timer-sp804.h
  clocksource/drivers/sp804: Cleanup clk_get_sys()
  dt-bindings: timer: renesas,cmt: Document r8a774e1 CMT support
  dt-bindings: timer: renesas,cmt: Document r8a7742 CMT support
  alarmtimer: Convert comma to semicolon
  timekeeping: Provide multi-timestamp accessor to NMI safe timekeeper
  timekeeping: Utilize local_clock() for NMI safe timekeeper during early boot
2020-10-12 11:27:54 -07:00
Qianli Zhao
b952caf2d5 timers: Mask invalid flags in do_init_timer()
do_init_timer() accepts any combination of timer flags handed in by the
caller without a sanity check, but only TIMER_DEFFERABLE, TIMER_PINNED and
TIMER_IRQSAFE are valid.

If the supplied flags have other bits set, this could result in
malfunction. If bits are set in TIMER_CPUMASK the first timer usage could
deference a cpu base which is outside the range of possible CPUs. If
TIMER_MIGRATION is set, then the switch_timer_base() will live lock.

Prevent that with a sanity check which warns when invalid flags are
supplied and masks them out.

[ tglx: Made it WARN_ON_ONCE() and added context to the changelog ]

Signed-off-by: Qianli Zhao <zhaoqianli@xiaomi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/9d79a8aa4eb56713af7379f99f062dedabcde140.1597326756.git.zhaoqianli@xiaomi.com
2020-09-24 22:12:18 +02:00
Stephen Boyd
f9e62f318f treewide: Make all debug_obj_descriptors const
This should make it harder for the kernel to corrupt the debug object
descriptor, used to call functions to fixup state and track debug objects,
by moving the structure to read-only memory.

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200815004027.2046113-3-swboyd@chromium.org
2020-09-24 21:56:25 +02:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Thomas Gleixner
1fb497dd00 posix-cpu-timers: Provide mechanisms to defer timer handling to task_work
Running posix CPU timers in hard interrupt context has a few downsides:

 - For PREEMPT_RT it cannot work as the expiry code needs to take
   sighand lock, which is a 'sleeping spinlock' in RT. The original RT
   approach of offloading the posix CPU timer handling into a high
   priority thread was clumsy and provided no real benefit in general.

 - For fine grained accounting it's just wrong to run this in context of
   the timer interrupt because that way a process specific CPU time is
   accounted to the timer interrupt.

 - Long running timer interrupts caused by a large amount of expiring
   timers which can be created and armed by unpriviledged user space.

There is no hard requirement to expire them in interrupt context.

If the signal is targeted at the task itself then it won't be delivered
before the task returns to user space anyway. If the signal is targeted at
a supervisor process then it might be slightly delayed, but posix CPU
timers are inaccurate anyway due to the fact that they are tied to the
tick.

Provide infrastructure to schedule task work which allows splitting the
posix CPU timer code into a quick check in interrupt context and a thread
context expiry and signal delivery function. This has to be enabled by
architectures as it requires that the architecture specific KVM
implementation handles pending task work before exiting to guest mode.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200730102337.783470146@linutronix.de
2020-08-06 16:50:59 +02:00
Linus Torvalds
442489c219 Merge tag 'timers-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Time, timers and related driver updates:

   - Prevent unnecessary timer softirq invocations by extending the
     tracking of the next expiring timer in the timer wheel beyond the
     existing NOHZ functionality.

     The tracking overhead at enqueue time is within the noise, but on
     sensitive workloads the avoidance of the soft interrupt invocation
     is a measurable improvement.

   - The obligatory new clocksource driver for Ingenic X100 OST

   - The usual fixes, improvements, cleanups and extensions for newer
     chip variants all over the driver space"

* tag 'timers-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
  timers: Recalculate next timer interrupt only when necessary
  clocksource/drivers/ingenic: Add support for the Ingenic X1000 OST.
  dt-bindings: timer: Add Ingenic X1000 OST bindings.
  clocksource/drivers: Replace HTTP links with HTTPS ones
  clocksource/drivers/nomadik-mtu: Handle 32kHz clock
  clocksource/drivers/sh_cmt: Use "kHz" for kilohertz
  clocksource/drivers/imx: Add support for i.MX TPM driver with ARM64
  clocksource/drivers/ingenic: Add high resolution timer support for SMP/SMT.
  timers: Lower base clock forwarding threshold
  timers: Remove must_forward_clk
  timers: Spare timer softirq until next expiry
  timers: Expand clk forward logic beyond nohz
  timers: Reuse next expiry cache after nohz exit
  timers: Always keep track of next expiry
  timers: Optimize _next_timer_interrupt() level iteration
  timers: Add comments about calc_index() ceiling work
  timers: Move trigger_dyntick_cpu() to enqueue_timer()
  timers: Use only bucket expiry for base->next_expiry value
  timers: Preserve higher bits of expiration on index calculation
  clocksource/drivers/timer-atmel-tcb: Add sama5d2 support
  ...
2020-08-04 18:17:37 -07:00
Willy Tarreau
f227e3ec3b random32: update the net random state on interrupt and activity
This modifies the first 32 bits out of the 128 bits of a random CPU's
net_rand_state on interrupt or CPU activity to complicate remote
observations that could lead to guessing the network RNG's internal
state.

Note that depending on some network devices' interrupt rate moderation
or binding, this re-seeding might happen on every packet or even almost
never.

In addition, with NOHZ some CPUs might not even get timer interrupts,
leaving their local state rarely updated, while they are running
networked processes making use of the random state.  For this reason, we
also perform this update in update_process_times() in order to at least
update the state when there is user or system activity, since it's the
only case we care about.

Reported-by: Amit Klein <aksecurity@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-29 10:35:37 -07:00
Frederic Weisbecker
31cd0e119d timers: Recalculate next timer interrupt only when necessary
The nohz tick code recalculates the timer wheel's next expiry on each idle
loop iteration.

On the other hand, the base next expiry is now always cached and updated
upon timer enqueue and execution. Only timer dequeue may leave
base->next_expiry out of date (but then its stale value won't ever go past
the actual next expiry to be recalculated).

Since recalculating the next_expiry isn't a free operation, especially when
the last wheel level is reached to find out that no timer has been enqueued
at all, reuse the next expiry cache when it is known to be reliable, which
it is most of the time.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200723151641.12236-1-frederic@kernel.org
2020-07-24 12:49:40 +02:00
Frederic Weisbecker
36cd28a4cd timers: Lower base clock forwarding threshold
There is nothing that prevents from forwarding the base clock if it's one
jiffy off. The reason for this arbitrary limit of two jiffies is historical
and does not longer exist.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-13-frederic@kernel.org
2020-07-17 21:55:25 +02:00
Frederic Weisbecker
0975fb565b timers: Remove must_forward_clk
There is no reason to keep this guard around. The code makes sure that
base->clk remains sane and won't be forwarded beyond jiffies nor set
backward.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-12-frederic@kernel.org
2020-07-17 21:55:25 +02:00
Frederic Weisbecker
d4f7dae870 timers: Spare timer softirq until next expiry
Now that the core timer infrastructure doesn't depend anymore on
periodic base->clk increments, even when the CPU is not in NO_HZ mode,
timer softirqs can be skipped until there are timers to expire.

Some spurious softirqs can still remain since base->next_expiry doesn't
keep track of canceled timers but this still reduces the number of softirqs
significantly: ~15 times less for HZ=1000 and ~5 times less for HZ=100.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-11-frederic@kernel.org
2020-07-17 21:55:24 +02:00
Frederic Weisbecker
1f8a4212dc timers: Expand clk forward logic beyond nohz
As for next_expiry, the base->clk catch up logic will be expanded beyond
NOHZ in order to avoid triggering useless softirqs.

If softirqs should only fire to expire pending timers, periodic base->clk
increments must be skippable for random amounts of time.  Therefore prepare
to catch-up with missing updates whenever an up-to-date base clock is
needed.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-10-frederic@kernel.org
2020-07-17 21:55:24 +02:00
Frederic Weisbecker
90d52f65f3 timers: Reuse next expiry cache after nohz exit
Now that the next expiry it tracked unconditionally when a timer is added,
this information can be reused on a tick firing after exiting nohz.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-9-frederic@kernel.org
2020-07-17 21:55:23 +02:00
Frederic Weisbecker
dc2a0f1fb2 timers: Always keep track of next expiry
So far next expiry was only tracked while the CPU was in nohz_idle mode
in order to cope with missing ticks that can't increment the base->clk
periodically anymore.

This logic is going to be expanded beyond nohz in order to spare timer
softirqs so do it unconditionally.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-8-frederic@kernel.org
2020-07-17 21:55:23 +02:00
Frederic Weisbecker
001ec1b392 timers: Optimize _next_timer_interrupt() level iteration
If a level has a timer that expires before reaching the next level, there
is no need to iterate further.

The next level is reached when the 3 lower bits of the current level are
cleared. If the next event happens before/during that, the next levels
won't provide an earlier expiration.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-7-frederic@kernel.org
2020-07-17 21:55:22 +02:00
Frederic Weisbecker
4468897211 timers: Add comments about calc_index() ceiling work
calc_index() adds 1 unit of the level granularity to the expiry passed
in parameter to ensure that the timer doesn't expire too early. Add a
comment to explain that and the resulting layout in the wheel.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-6-frederic@kernel.org
2020-07-17 21:55:22 +02:00
Frederic Weisbecker
9a2b764b06 timers: Move trigger_dyntick_cpu() to enqueue_timer()
Consolidate the code by calling trigger_dyntick_cpu() from
enqueue_timer() instead of calling it from all its callers.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-5-frederic@kernel.org
2020-07-17 21:55:22 +02:00
Anna-Maria Behnsen
1f32cab0db timers: Use only bucket expiry for base->next_expiry value
The bucket expiry time is the effective expriy time of timers and is
greater than or equal to the requested timer expiry time. This is due
to the guarantee that timers never expire early and the reduced expiry
granularity in the secondary wheel levels.

When a timer is enqueued, trigger_dyntick_cpu() checks whether the
timer is the new first timer. This check compares next_expiry with
the requested timer expiry value and not with the effective expiry
value of the bucket into which the timer was queued.

Storing the requested timer expiry value in base->next_expiry can lead
to base->clk going backwards if the requested timer expiry value is
smaller than base->clk. Commit 30c66fc30e ("timer: Prevent base->clk
from moving backward") worked around this by preventing the store when
timer->expiry is before base->clk, but did not fix the underlying
problem.

Use the expiry value of the bucket into which the timer is queued to
do the new first timer check. This fixes the base->clk going backward
problem.

The workaround of commit 30c66fc30e ("timer: Prevent base->clk from
moving backward") in trigger_dyntick_cpu() is not longer necessary as the
timers bucket expiry is guaranteed to be greater than or equal base->clk.

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200717140551.29076-4-frederic@kernel.org
2020-07-17 21:55:21 +02:00
Frederic Weisbecker
3d2e83a2a6 timers: Preserve higher bits of expiration on index calculation
The higher bits of the timer expiration are cropped while calling
calc_index() due to the implicit cast from unsigned long to unsigned int.

This loss shouldn't have consequences on the current code since all the
computation to calculate the index is done on the lower 32 bits.

However to prepare for returning the actual bucket expiration from
calc_index() in order to properly fix base->next_expiry updates, the higher
bits need to be preserved.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200717140551.29076-3-frederic@kernel.org
2020-07-17 21:55:21 +02:00
Frederic Weisbecker
e2a71bdea8 timer: Fix wheel index calculation on last level
When an expiration delta falls into the last level of the wheel, that delta
has be compared against the maximum possible delay and reduced to fit in if
necessary.

However instead of comparing the delta against the maximum, the code
compares the actual expiry against the maximum. Then instead of fixing the
delta to fit in, it sets the maximum delta as the expiry value.

This can result in various undesired outcomes, the worst possible one
being a timer expiring 15 days ahead to fire immediately.

Fixes: 500462a9de ("timers: Switch to a non-cascading wheel")
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200717140551.29076-2-frederic@kernel.org
2020-07-17 21:44:05 +02:00
Frederic Weisbecker
30c66fc30e timer: Prevent base->clk from moving backward
When a timer is enqueued with a negative delta (ie: expiry is below
base->clk), it gets added to the wheel as expiring now (base->clk).

Yet the value that gets stored in base->next_expiry, while calling
trigger_dyntick_cpu(), is the initial timer->expires value. The
resulting state becomes:

	base->next_expiry < base->clk

On the next timer enqueue, forward_timer_base() may accidentally
rewind base->clk. As a possible outcome, timers may expire way too
early, the worst case being that the highest wheel levels get spuriously
processed again.

To prevent from that, make sure that base->next_expiry doesn't get below
base->clk.

Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200703010657.2302-1-frederic@kernel.org
2020-07-09 11:56:57 +02:00
Christoph Hellwig
32927393dc sysctl: pass kernel pointers to ->proc_handler
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from  userspace in common code.  This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-27 02:07:40 -04:00
Linus Torvalds
dbb381b619 Merge tag 'timers-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timekeeping and timer updates from Thomas Gleixner:
 "Core:

   - Consolidation of the vDSO build infrastructure to address the
     difficulties of cross-builds for ARM64 compat vDSO libraries by
     restricting the exposure of header content to the vDSO build.

     This is achieved by splitting out header content into separate
     headers. which contain only the minimaly required information which
     is necessary to build the vDSO. These new headers are included from
     the kernel headers and the vDSO specific files.

   - Enhancements to the generic vDSO library allowing more fine grained
     control over the compiled in code, further reducing architecture
     specific storage and preparing for adopting the generic library by
     PPC.

   - Cleanup and consolidation of the exit related code in posix CPU
     timers.

   - Small cleanups and enhancements here and there

  Drivers:

   - The obligatory new drivers: Ingenic JZ47xx and X1000 TCU support

   - Correct the clock rate of PIT64b global clock

   - setup_irq() cleanup

   - Preparation for PWM and suspend support for the TI DM timer

   - Expand the fttmr010 driver to support ast2600 systems

   - The usual small fixes, enhancements and cleanups all over the
     place"

* tag 'timers-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits)
  Revert "clocksource/drivers/timer-probe: Avoid creating dead devices"
  vdso: Fix clocksource.h macro detection
  um: Fix header inclusion
  arm64: vdso32: Enable Clang Compilation
  lib/vdso: Enable common headers
  arm: vdso: Enable arm to use common headers
  x86/vdso: Enable x86 to use common headers
  mips: vdso: Enable mips to use common headers
  arm64: vdso32: Include common headers in the vdso library
  arm64: vdso: Include common headers in the vdso library
  arm64: Introduce asm/vdso/processor.h
  arm64: vdso32: Code clean up
  linux/elfnote.h: Replace elf.h with UAPI equivalent
  scripts: Fix the inclusion order in modpost
  common: Introduce processor.h
  linux/ktime.h: Extract common header for vDSO
  linux/jiffies.h: Extract common header for vDSO
  linux/time64.h: Extract common header for vDSO
  linux/time32.h: Extract common header for vDSO
  linux/time.h: Extract common header for vDSO
  ...
2020-03-30 18:51:47 -07:00
Eric Dumazet
90c018942c timer: Use hlist_unhashed_lockless() in timer_pending()
The timer_pending() function is mostly used in lockless contexts, so
Without proper annotations, KCSAN might detect a data-race [1].

Using hlist_unhashed_lockless() instead of hand-coding it seems
appropriate (as suggested by Paul E. McKenney).

[1]

BUG: KCSAN: data-race in del_timer / detach_if_pending

write to 0xffff88808697d870 of 8 bytes by task 10 on cpu 0:
 __hlist_del include/linux/list.h:764 [inline]
 detach_timer kernel/time/timer.c:815 [inline]
 detach_if_pending+0xcd/0x2d0 kernel/time/timer.c:832
 try_to_del_timer_sync+0x60/0xb0 kernel/time/timer.c:1226
 del_timer_sync+0x6b/0xa0 kernel/time/timer.c:1365
 schedule_timeout+0x2d2/0x6e0 kernel/time/timer.c:1896
 rcu_gp_fqs_loop+0x37c/0x580 kernel/rcu/tree.c:1639
 rcu_gp_kthread+0x143/0x230 kernel/rcu/tree.c:1799
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff88808697d870 of 8 bytes by task 12060 on cpu 1:
 del_timer+0x3b/0xb0 kernel/time/timer.c:1198
 sk_stop_timer+0x25/0x60 net/core/sock.c:2845
 inet_csk_clear_xmit_timers+0x69/0xa0 net/ipv4/inet_connection_sock.c:523
 tcp_clear_xmit_timers include/net/tcp.h:606 [inline]
 tcp_v4_destroy_sock+0xa3/0x3f0 net/ipv4/tcp_ipv4.c:2096
 inet_csk_destroy_sock+0xf4/0x250 net/ipv4/inet_connection_sock.c:836
 tcp_close+0x6f3/0x970 net/ipv4/tcp.c:2497
 inet_release+0x86/0x100 net/ipv4/af_inet.c:427
 __sock_release+0x85/0x160 net/socket.c:590
 sock_close+0x24/0x30 net/socket.c:1268
 __fput+0x1e1/0x520 fs/file_table.c:280
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 12060 Comm: syz-executor.5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine,

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
[ paulmck: Pulled in Eric's later amendments. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-02-20 15:58:22 -08:00
Alexander Popov
6e317c32fd timer: Improve the comment describing schedule_timeout()
When working commit 6dcd5d7a7a, a mistake was noticed by Linus:
schedule_timeout() was called without setting the task state to anything
particular.

It calls the scheduler, but doesn't delay anything, because the task stays
runnable. That happens because sched_submit_work() does nothing for tasks
in TASK_RUNNING state.

That turned out to be the intended behavior. Adding a WARN() is not useful
as the task could be woken up right after setting the state and before
reaching schedule_timeout().

Improve the comment about schedule_timeout() and describe that more
explicitly.

Signed-off-by: Alexander Popov <alex.popov@linux.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200117225900.16340-1-alex.popov@linux.com
2020-02-17 20:12:19 +01:00
Li RongQing
e430d802d6 timer: Read jiffies once when forwarding base clk
The timer delayed for more than 3 seconds warning was triggered during
testing.

  Workqueue: events_unbound sched_tick_remote
  RIP: 0010:sched_tick_remote+0xee/0x100
  ...
  Call Trace:
   process_one_work+0x18c/0x3a0
   worker_thread+0x30/0x380
   kthread+0x113/0x130
   ret_from_fork+0x22/0x40

The reason is that the code in collect_expired_timers() uses jiffies
unprotected:

    if (next_event > jiffies)
        base->clk = jiffies;

As the compiler is allowed to reload the value base->clk can advance
between the check and the store and in the worst case advance farther than
next event. That causes the timer expiry to be delayed until the wheel
pointer wraps around.

Convert the code to use READ_ONCE()

Fixes: 236968383c ("timers: Optimize collect_expired_timers() for NOHZ")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Liang ZhiCheng <liangzhicheng@baidu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1568894687-14499-1-git-send-email-lirongqing@baidu.com
2019-09-19 17:50:11 +02:00
Thomas Gleixner
dce3e8fd03 posix-cpu-timers: Remove tsk argument from run_posix_cpu_timers()
It's always current. Don't give people wrong ideas.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.945469967@linutronix.de
2019-08-21 20:27:16 +02:00
Anna-Maria Gleixner
030dcdd197 timers: Prepare support for PREEMPT_RT
When PREEMPT_RT is enabled, the soft interrupt thread can be preempted.  If
the soft interrupt thread is preempted in the middle of a timer callback,
then calling del_timer_sync() can lead to two issues:

  - If the caller is on a remote CPU then it has to spin wait for the timer
    handler to complete. This can result in unbound priority inversion.

  - If the caller originates from the task which preempted the timer
    handler on the same CPU, then spin waiting for the timer handler to
    complete is never going to end.

To avoid these issues, add a new lock to the timer base which is held
around the execution of the timer callbacks. If del_timer_sync() detects
that the timer callback is currently running, it blocks on the expiry
lock. When the callback is finished, the expiry lock is dropped by the
softirq thread which wakes up the waiter and the system makes progress.

This addresses both the priority inversion and the life lock issues.

This mechanism is not used for timers which are marked IRQSAFE as for those
preemption is disabled accross the callback and therefore this situation
cannot happen. The callbacks for such timers need to be individually
audited for RT compliance.

The same issue can happen in virtual machines when the vCPU which runs a
timer callback is scheduled out. If a second vCPU of the same guest calls
del_timer_sync() it will spin wait for the other vCPU to be scheduled back
in. The expiry lock mechanism would avoid that. It'd be trivial to enable
this when paravirt spinlocks are enabled in a guest, but it's not clear
whether this is an actual problem in the wild, so for now it's an RT only
mechanism.

As the softirq thread can be preempted with PREEMPT_RT=y, the SMP variant
of del_timer_sync() needs to be used on UP as well.

[ tglx: Refactored it for mainline ]

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.832418500@linutronix.de
2019-08-01 20:51:22 +02:00
Linus Torvalds
0968621917 Merge tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:

 - Allow state reset of printk_once() calls.

 - Prevent crashes when dereferencing invalid pointers in vsprintf().
   Only the first byte is checked for simplicity.

 - Make vsprintf warnings consistent and inlined.

 - Treewide conversion of obsolete %pf, %pF to %ps, %pF printf
   modifiers.

 - Some clean up of vsprintf and test_printf code.

* tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  lib/vsprintf: Make function pointer_string static
  vsprintf: Limit the length of inlined error messages
  vsprintf: Avoid confusion between invalid address and value
  vsprintf: Prevent crash when dereferencing invalid pointers
  vsprintf: Consolidate handling of unknown pointer specifiers
  vsprintf: Factor out %pO handler as kobject_string()
  vsprintf: Factor out %pV handler as va_format()
  vsprintf: Factor out %p[iI] handler as ip_addr_string()
  vsprintf: Do not check address of well-known strings
  vsprintf: Consistent %pK handling for kptr_restrict == 0
  vsprintf: Shuffle restricted_pointer()
  printk: Tie printk_once / printk_deferred_once into .data.once for reset
  treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
  lib/test_printf: Switch to bitmap_zalloc()
2019-05-07 09:18:12 -07:00