Changes in 5.10.65
locking/mutex: Fix HANDOFF condition
regmap: fix the offset of register error log
regulator: tps65910: Silence deferred probe error
crypto: mxs-dcp - Check for DMA mapping errors
sched/deadline: Fix reset_on_fork reporting of DL tasks
power: supply: axp288_fuel_gauge: Report register-address on readb / writeb errors
crypto: omap-sham - clear dma flags only after omap_sham_update_dma_stop()
sched/deadline: Fix missing clock update in migrate_task_rq_dl()
rcu/tree: Handle VM stoppage in stall detection
EDAC/mce_amd: Do not load edac_mce_amd module on guests
posix-cpu-timers: Force next expiration recalc after itimer reset
hrtimer: Avoid double reprogramming in __hrtimer_start_range_ns()
hrtimer: Ensure timerfd notification for HIGHRES=n
udf: Check LVID earlier
udf: Fix iocharset=utf8 mount option
isofs: joliet: Fix iocharset=utf8 mount option
bcache: add proper error unwinding in bcache_device_init
blk-throtl: optimize IOPS throttle for large IO scenarios
nvme-tcp: don't update queue count when failing to set io queues
nvme-rdma: don't update queue count when failing to set io queues
nvmet: pass back cntlid on successful completion
power: supply: smb347-charger: Add missing pin control activation
power: supply: max17042_battery: fix typo in MAx17042_TOFF
s390/cio: add dev_busid sysfs entry for each subchannel
s390/zcrypt: fix wrong offset index for APKA master key valid state
libata: fix ata_host_start()
crypto: omap - Fix inconsistent locking of device lists
crypto: qat - do not ignore errors from enable_vf2pf_comms()
crypto: qat - handle both source of interrupt in VF ISR
crypto: qat - fix reuse of completion variable
crypto: qat - fix naming for init/shutdown VF to PF notifications
crypto: qat - do not export adf_iov_putmsg()
fcntl: fix potential deadlock for &fasync_struct.fa_lock
udf_get_extendedattr() had no boundary checks.
s390/kasan: fix large PMD pages address alignment check
s390/pci: fix misleading rc in clp_set_pci_fn()
s390/debug: keep debug data on resize
s390/debug: fix debug area life cycle
s390/ap: fix state machine hang after failure to enable irq
power: supply: cw2015: use dev_err_probe to allow deferred probe
m68k: emu: Fix invalid free in nfeth_cleanup()
sched/numa: Fix is_core_idle()
sched: Fix UCLAMP_FLAG_IDLE setting
rcu: Fix to include first blocked task in stall warning
rcu: Add lockdep_assert_irqs_disabled() to rcu_sched_clock_irq() and callees
rcu: Fix stall-warning deadlock due to non-release of rcu_node ->lock
m68k: Fix invalid RMW_INSNS on CPUs that lack CAS
block: return ELEVATOR_DISCARD_MERGE if possible
spi: spi-fsl-dspi: Fix issue with uninitialized dma_slave_config
spi: spi-pic32: Fix issue with uninitialized dma_slave_config
genirq/timings: Fix error return code in irq_timings_test_irqs()
irqchip/loongson-pch-pic: Improve edge triggered interrupt support
lib/mpi: use kcalloc in mpi_resize
clocksource/drivers/sh_cmt: Fix wrong setting if don't request IRQ for clock source channel
block: nbd: add sanity check for first_minor
spi: coldfire-qspi: Use clk_disable_unprepare in the remove function
irqchip/gic-v3: Fix priority comparison when non-secure priorities are used
crypto: qat - use proper type for vf_mask
certs: Trigger creation of RSA module signing key if it's not an RSA key
tpm: ibmvtpm: Avoid error message when process gets signal while waiting
x86/mce: Defer processing of early errors
spi: davinci: invoke chipselect callback
blk-crypto: fix check for too-large dun_bytes
regulator: vctrl: Use locked regulator_get_voltage in probe path
regulator: vctrl: Avoid lockdep warning in enable/disable ops
spi: sprd: Fix the wrong WDG_LOAD_VAL
spi: spi-zynq-qspi: use wait_for_completion_timeout to make zynq_qspi_exec_mem_op not interruptible
EDAC/i10nm: Fix NVDIMM detection
drm/panfrost: Fix missing clk_disable_unprepare() on error in panfrost_clk_init()
drm/gma500: Fix end of loop tests for list_for_each_entry
ASoC: mediatek: mt8183: Fix Unbalanced pm_runtime_enable in mt8183_afe_pcm_dev_probe
media: TDA1997x: enable EDID support
leds: is31fl32xx: Fix missing error code in is31fl32xx_parse_dt()
soc: rockchip: ROCKCHIP_GRF should not default to y, unconditionally
media: cxd2880-spi: Fix an error handling path
drm/of: free the right object
bpf: Fix a typo of reuseport map in bpf.h.
bpf: Fix potential memleak and UAF in the verifier.
drm/of: free the iterator object on failure
gve: fix the wrong AdminQ buffer overflow check
libbpf: Fix the possible memory leak on error
ARM: dts: aspeed-g6: Fix HVI3C function-group in pinctrl dtsi
arm64: dts: renesas: r8a77995: draak: Remove bogus adv7511w properties
i40e: improve locking of mac_filter_hash
soc: qcom: rpmhpd: Use corner in power_off
libbpf: Fix removal of inner map in bpf_object__create_map
gfs2: Fix memory leak of object lsi on error return path
firmware: fix theoretical UAF race with firmware cache and resume
driver core: Fix error return code in really_probe()
ionic: cleanly release devlink instance
media: dvb-usb: fix uninit-value in dvb_usb_adapter_dvb_init
media: dvb-usb: fix uninit-value in vp702x_read_mac_addr
media: dvb-usb: Fix error handling in dvb_usb_i2c_init
media: go7007: fix memory leak in go7007_usb_probe
media: go7007: remove redundant initialization
media: rockchip/rga: use pm_runtime_resume_and_get()
media: rockchip/rga: fix error handling in probe
media: coda: fix frame_mem_ctrl for YUV420 and YVU420 formats
media: atomisp: fix the uninitialized use and rename "retvalue"
Bluetooth: sco: prevent information leak in sco_conn_defer_accept()
6lowpan: iphc: Fix an off-by-one check of array index
drm/amdgpu/acp: Make PM domain really work
tcp: seq_file: Avoid skipping sk during tcp_seek_last_pos
ARM: dts: meson8: Use a higher default GPU clock frequency
ARM: dts: meson8b: odroidc1: Fix the pwm regulator supply properties
ARM: dts: meson8b: mxq: Fix the pwm regulator supply properties
ARM: dts: meson8b: ec100: Fix the pwm regulator supply properties
net/mlx5e: Prohibit inner indir TIRs in IPoIB
net/mlx5e: Block LRO if firmware asks for tunneled LRO
cgroup/cpuset: Fix a partition bug with hotplug
drm: mxsfb: Enable recovery on underflow
drm: mxsfb: Increase number of outstanding requests on V4 and newer HW
drm: mxsfb: Clear FIFO_CLEAR bit
net: cipso: fix warnings in netlbl_cipsov4_add_std
Bluetooth: mgmt: Fix wrong opcode in the response for add_adv cmd
arm64: dts: renesas: rzg2: Convert EtherAVB to explicit delay handling
arm64: dts: renesas: hihope-rzg2-ex: Add EtherAVB internal rx delay
devlink: Break parameter notification sequence to be before/after unload/load driver
net/mlx5: Fix missing return value in mlx5_devlink_eswitch_inline_mode_set()
i2c: highlander: add IRQ check
leds: lt3593: Put fwnode in any case during ->probe()
leds: trigger: audio: Add an activate callback to ensure the initial brightness is set
media: em28xx-input: fix refcount bug in em28xx_usb_disconnect
media: venus: venc: Fix potential null pointer dereference on pointer fmt
PCI: PM: Avoid forcing PCI_D0 for wakeup reasons inconsistently
PCI: PM: Enable PME if it can be signaled from D3cold
bpf, samples: Add missing mprog-disable to xdp_redirect_cpu's optstring
soc: qcom: smsm: Fix missed interrupts if state changes while masked
debugfs: Return error during {full/open}_proxy_open() on rmmod
Bluetooth: increase BTNAMSIZ to 21 chars to fix potential buffer overflow
PM: EM: Increase energy calculation precision
selftests/bpf: Fix bpf-iter-tcp4 test to print correctly the dest IP
drm/msm/mdp4: refactor HW revision detection into read_mdp_hw_revision
drm/msm/mdp4: move HW revision detection to earlier phase
drm/msm/dpu: make dpu_hw_ctl_clear_all_blendstages clear necessary LMs
arm64: dts: exynos: correct GIC CPU interfaces address range on Exynos7
counter: 104-quad-8: Return error when invalid mode during ceiling_write
cgroup/cpuset: Miscellaneous code cleanup
cgroup/cpuset: Fix violation of cpuset locking rule
ASoC: Intel: Fix platform ID matching
Bluetooth: fix repeated calls to sco_sock_kill
drm/msm/dsi: Fix some reference counted resource leaks
net/mlx5: Register to devlink ingress VLAN filter trap
net/mlx5: Fix unpublish devlink parameters
ASoC: rt5682: Implement remove callback
ASoC: rt5682: Properly turn off regulators if wrong device ID
usb: dwc3: meson-g12a: add IRQ check
usb: dwc3: qcom: add IRQ check
usb: gadget: udc: at91: add IRQ check
usb: gadget: udc: s3c2410: add IRQ check
usb: phy: fsl-usb: add IRQ check
usb: phy: twl6030: add IRQ checks
usb: gadget: udc: renesas_usb3: Fix soc_device_match() abuse
selftests/bpf: Fix test_core_autosize on big-endian machines
devlink: Clear whole devlink_flash_notify struct
samples: pktgen: add missing IPv6 option to pktgen scripts
Bluetooth: Move shutdown callback before flushing tx and rx queue
PM: cpu: Make notifier chain use a raw_spinlock_t
usb: host: ohci-tmio: add IRQ check
usb: phy: tahvo: add IRQ check
libbpf: Re-build libbpf.so when libbpf.map changes
mac80211: Fix insufficient headroom issue for AMSDU
locking/lockdep: Mark local_lock_t
locking/local_lock: Add missing owner initialization
lockd: Fix invalid lockowner cast after vfs_test_lock
nfsd4: Fix forced-expiry locking
arm64: dts: marvell: armada-37xx: Extend PCIe MEM space
clk: staging: correct reference to config IOMEM to config HAS_IOMEM
i2c: synquacer: fix deferred probing
firmware: raspberrypi: Keep count of all consumers
firmware: raspberrypi: Fix a leak in 'rpi_firmware_get()'
usb: gadget: mv_u3d: request_irq() after initializing UDC
mm/swap: consider max pages in iomap_swapfile_add_extent
lkdtm: replace SCSI_DISPATCH_CMD with SCSI_QUEUE_RQ
Bluetooth: add timeout sanity check to hci_inquiry
i2c: iop3xx: fix deferred probing
i2c: s3c2410: fix IRQ check
i2c: fix platform_get_irq.cocci warnings
i2c: hix5hd2: fix IRQ check
gfs2: init system threads before freeze lock
rsi: fix error code in rsi_load_9116_firmware()
rsi: fix an error code in rsi_probe()
ASoC: Intel: kbl_da7219_max98927: Fix format selection for max98373
ASoC: Intel: Skylake: Leave data as is when invoking TLV IPCs
ASoC: Intel: Skylake: Fix module resource and format selection
mmc: sdhci: Fix issue with uninitialized dma_slave_config
mmc: dw_mmc: Fix issue with uninitialized dma_slave_config
mmc: moxart: Fix issue with uninitialized dma_slave_config
bpf: Fix possible out of bound write in narrow load handling
CIFS: Fix a potencially linear read overflow
i2c: mt65xx: fix IRQ check
i2c: xlp9xx: fix main IRQ check
usb: ehci-orion: Handle errors of clk_prepare_enable() in probe
usb: bdc: Fix an error handling path in 'bdc_probe()' when no suitable DMA config is available
usb: bdc: Fix a resource leak in the error handling path of 'bdc_probe()'
tty: serial: fsl_lpuart: fix the wrong mapbase value
ASoC: wcd9335: Fix a double irq free in the remove function
ASoC: wcd9335: Fix a memory leak in the error handling path of the probe function
ASoC: wcd9335: Disable irq on slave ports in the remove function
iwlwifi: follow the new inclusive terminology
iwlwifi: skip first element in the WTAS ACPI table
ice: Only lock to update netdev dev_addr
ath6kl: wmi: fix an error code in ath6kl_wmi_sync_point()
atlantic: Fix driver resume flow.
bcma: Fix memory leak for internally-handled cores
brcmfmac: pcie: fix oops on failure to resume and reprobe
ipv6: make exception cache less predictible
ipv4: make exception cache less predictible
net: sched: Fix qdisc_rate_table refcount leak when get tcf_block failed
net: qualcomm: fix QCA7000 checksum handling
octeontx2-af: Fix loop in free and unmap counter
octeontx2-af: Fix static code analyzer reported issues
octeontx2-af: Set proper errorcode for IPv4 checksum errors
ipv4: fix endianness issue in inet_rtm_getroute_build_skb()
ASoC: rt5682: Remove unused variable in rt5682_i2c_remove()
iwlwifi Add support for ax201 in Samsung Galaxy Book Flex2 Alpha
f2fs: guarantee to write dirty data when enabling checkpoint back
time: Handle negative seconds correctly in timespec64_to_ns()
io_uring: IORING_OP_WRITE needs hash_reg_file set
bio: fix page leak bio_add_hw_page failure
tty: Fix data race between tiocsti() and flush_to_ldisc()
perf/x86/amd/ibs: Extend PERF_PMU_CAP_NO_EXCLUDE to IBS Op
x86/resctrl: Fix a maybe-uninitialized build warning treated as error
Revert "KVM: x86: mmu: Add guest physical address check in translate_gpa()"
KVM: s390: index kvm->arch.idle_mask by vcpu_idx
KVM: x86: Update vCPU's hv_clock before back to guest when tsc_offset is adjusted
KVM: VMX: avoid running vmx_handle_exit_irqoff in case of emulation
KVM: nVMX: Unconditionally clear nested.pi_pending on nested VM-Enter
ARM: dts: at91: add pinctrl-{names, 0} for all gpios
fuse: truncate pagecache on atomic_o_trunc
fuse: flush extending writes
IMA: remove -Wmissing-prototypes warning
IMA: remove the dependency on CRYPTO_MD5
fbmem: don't allow too huge resolutions
backlight: pwm_bl: Improve bootloader/kernel device handover
clk: kirkwood: Fix a clocking boot regression
Linux 5.10.65
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ie0b9306ba6ee4193de3200df7cdacaeba152b83e
[ Upstream commit dc87740c8a6806bd2162bfb441770e4e53be5601 ]
If rcu_print_task_stall() is invoked on an rcu_node structure that does
not contain any tasks blocking the current grace period, it takes an
early exit that fails to release that rcu_node structure's lock. This
results in a self-deadlock, which is detected by lockdep.
To reproduce this bug:
tools/testing/selftests/rcutorture/bin/kvm.sh --allcpus --duration 3 --trust-make --configs "TREE03" --kconfig "CONFIG_PROVE_LOCKING=y" --bootargs "rcutorture.stall_cpu=30 rcutorture.stall_cpu_block=1 rcutorture.fwd_progress=0 rcutorture.test_boost=0"
This will also result in other complaints, including RCU's scheduler
hook complaining about blocking rather than preemption and an rcutorture
writer stall.
Only a partial RCU CPU stall warning message will be printed because of
the self-deadlock.
This commit therefore releases the lock on the rcu_print_task_stall()
function's early exit path.
Fixes: c583bcb8f5 ("rcu: Don't invoke try_invoke_on_locked_down_task() with irqs disabled")
Tested-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a649d25dcc671a33b9cc3176411920fdc5fbd98e ]
This commit adds a number of lockdep_assert_irqs_disabled() calls
to rcu_sched_clock_irq() and a number of the functions that it calls.
The point of this is to help track down a situation where lockdep appears
to be insisting that interrupts are enabled within these functions, which
should only ever be invoked from the scheduling-clock interrupt handler.
Link: https://lore.kernel.org/lkml/20201111133813.GA81547@elver.google.com/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e6a901a44f76878ed1653626c9ff4cfc5a3f58f8 ]
The for loop in rcu_print_task_stall() always omits ts[0], which points
to the first task blocking the stalled grace period. This in turn fails
to count this first task, which means that ndetected will be equal to
zero when all CPUs have passed through their quiescent states and only
one task is blocking the stalled grace period. This zero value for
ndetected will in turn result in an incorrect "All QSes seen" message:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-1 rcu_node (CPUs 12-23):
(detected by 15, t=6504 jiffies, g=164777, q=9011209)
rcu: All QSes seen, last rcu_preempt kthread activity 1 (4295252379-4295252378), jiffies_till_next_fqs=1, root ->qsmask 0x2
BUG: sleeping function called from invalid context at include/linux/uaccess.h:156
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 70613, name: msgstress04
INFO: lockdep is turned off.
Preemption disabled at:
[<ffff8000104031a4>] create_object.isra.0+0x204/0x4b0
CPU: 15 PID: 70613 Comm: msgstress04 Kdump: loaded Not tainted
5.12.2-yoctodev-standard #1
Hardware name: Marvell OcteonTX CN96XX board (DT)
Call trace:
dump_backtrace+0x0/0x2cc
show_stack+0x24/0x30
dump_stack+0x110/0x188
___might_sleep+0x214/0x2d0
__might_sleep+0x7c/0xe0
This commit therefore fixes the loop to include ts[0].
Fixes: c583bcb8f5 ("rcu: Don't invoke try_invoke_on_locked_down_task() with irqs disabled")
Tested-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ccfc9dd6914feaa9a81f10f9cce56eb0f7712264 ]
The soft watchdog timer function checks if a virtual machine
was suspended and hence what looks like a lockup in fact
is a false positive.
This is what kvm_check_and_clear_guest_paused() does: it
tests guest PVCLOCK_GUEST_STOPPED (which is set by the host)
and if it's set then we need to touch all watchdogs and bail
out.
Watchdog timer function runs from IRQ, so PVCLOCK_GUEST_STOPPED
check works fine.
There is, however, one more watchdog that runs from IRQ, so
watchdog timer fn races with it, and that watchdog is not aware
of PVCLOCK_GUEST_STOPPED - RCU stall detector.
apic_timer_interrupt()
smp_apic_timer_interrupt()
hrtimer_interrupt()
__hrtimer_run_queues()
tick_sched_timer()
tick_sched_handle()
update_process_times()
rcu_sched_clock_irq()
This triggers RCU stalls on our devices during VM resume.
If tick_sched_handle()->rcu_sched_clock_irq() runs on a VCPU
before watchdog_timer_fn()->kvm_check_and_clear_guest_paused()
then there is nothing on this VCPU that touches watchdogs and
RCU reads stale gp stall timestamp and new jiffies value, which
makes it think that RCU has stalled.
Make RCU stall watchdog aware of PVCLOCK_GUEST_STOPPED and
don't report RCU stalls when we resume the VM.
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
If rcu_print_task_stall() is invoked on an rcu_node structure that does
not contain any tasks blocking the current grace period, it takes an
early exit that fails to release that rcu_node structure's lock. This
results in a self-deadlock, which is detected by lockdep.
To reproduce this bug:
tools/testing/selftests/rcutorture/bin/kvm.sh --allcpus --duration 3 --trust-make --configs "TREE03" --kconfig "CONFIG_PROVE_LOCKING=y" --bootargs "rcutorture.stall_cpu=30 rcutorture.stall_cpu_block=1 rcutorture.fwd_progress=0 rcutorture.test_boost=0"
This will also result in other complaints, including RCU's scheduler
hook complaining about blocking rather than preemption and an rcutorture
writer stall.
Only a partial RCU CPU stall warning message will be printed because of
the self-deadlock.
This commit therefore releases the lock on the rcu_print_task_stall()
function's early exit path.
Fixes: c583bcb8f5 ("rcu: Don't invoke try_invoke_on_locked_down_task() with irqs disabled")
Tested-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
BUG: 196874644
(cherry picked from commit dc87740c8a6806bd2162bfb441770e4e53be5601
https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev)
Signed-off-by: Cheng Jui Wang <cheng-jui.wang@mediatek.com>
Change-Id: I0942973e3fbac2d666d8eb9ed59b1701af13248a
This commit adds a trace event which allows tracing the beginnings of RCU
CPU stall warnings on systems where sysctl_panic_on_rcu_stall is disabled.
The first parameter is the name of RCU flavor like other trace events.
The second parameter indicates whether this is a stall of an expedited
grace period, a self-detected stall of a normal grace period, or a stall
of a normal grace period detected by some CPU other than the one that
is stalled.
RCU CPU stall warnings are often caused by external-to-RCU issues,
for example, in interrupt handling or task scheduling. Therefore,
this event uses TRACE_EVENT, not TRACE_EVENT_RCU, to avoid requiring
those interested in tracing RCU CPU stalls to rebuild their kernels
with CONFIG_RCU_TRACE=y.
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Sangmoon Kim <sangmoon.kim@samsung.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
(cherry picked from commit 71580d6503f747f1b06ef8dbb7cdbbe20400a2ec
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev)
Bug: 177483057
Change-Id: Ie2f0340725a2fb582d026ecfaf5e1d35cc90fece
Signed-off-by: Sangmoon Kim <sangmoon.kim@samsung.com>
The try_invoke_on_locked_down_task() function requires that
interrupts be enabled, but it is called with interrupts disabled from
rcu_print_task_stall(), resulting in an "IRQs not enabled as expected"
diagnostic. This commit therefore updates rcu_print_task_stall()
to accumulate a list of the first few tasks while holding the current
leaf rcu_node structure's ->lock, then releases that lock and only then
uses try_invoke_on_locked_down_task() to attempt to obtain per-task
detailed information. Of course, as soon as ->lock is released, the
task might exit, so the get_task_struct() function is used to prevent
the task structure from going away in the meantime.
Link: https://lore.kernel.org/lkml/000000000000903d5805ab908fc4@google.com/
Fixes: 5bef8da66a ("rcu: Add per-task state to RCU CPU stall warnings")
Reported-by: syzbot+cb3b69ae80afd6535b0e@syzkaller.appspotmail.com
Reported-by: syzbot+f04854e1c5c9e913cc27@syzkaller.appspotmail.com
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Given that sysfs can change the value of rcu_cpu_stall_ftrace_dump at any
time, this commit adds a READ_ONCE() to the accesses to that variable.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Given that sysfs can change the value of rcu_kick_kthreads at any time,
this commit adds a READ_ONCE() to the sole access to that variable.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit removes the variable rnp from check_slow_task(), which
is defined, assigned to, but not otherwise used.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds a count of the callbacks invoked to the per-CPU rcu_data
structure. This count is printed by the show_rcu_gp_kthreads() that
is invoked by rcutorture and the RCU CPU stall-warning code. It is also
intended for use by drgn.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
- Add a SPDX header;
- Adjust document and section titles;
- Fix list markups;
- Some whitespace fixes and new line breaks;
- Mark literal blocks as such;
- Add it to RCU/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Pull tty/serial driver updates from Greg KH:
"Here is the tty and serial driver updates for 5.8-rc1
Nothing huge at all, just a lot of little serial driver fixes, updates
for new devices and features, and other small things. Full details are
in the shortlog.
All of these have been in linux-next with no issues for a while"
* tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (67 commits)
tty: serial: qcom_geni_serial: Add 51.2MHz frequency support
tty: serial: imx: clear Ageing Timer Interrupt in handler
serial: 8250_fintek: Add F81966 Support
sc16is7xx: Add flag to activate IrDA mode
dt-bindings: sc16is7xx: Add flag to activate IrDA mode
serial: 8250: Support rs485 bus termination GPIO
serial: 8520_port: Fix function param documentation
dt-bindings: serial: Add binding for rs485 bus termination GPIO
vt: keyboard: avoid signed integer overflow in k_ascii
serial: 8250: Enable 16550A variants by default on non-x86
tty: hvc_console, fix crashes on parallel open/close
serial: imx: Initialize lock for non-registered console
sc16is7xx: Read the LSR register for basic device presence check
sc16is7xx: Allow sharing the IRQ line
sc16is7xx: Use threaded IRQ
sc16is7xx: Always use falling edge IRQ
tty: n_gsm: Fix bogus i++ in gsm_data_kick
tty: n_gsm: Remove unnecessary test in gsm_print_packet()
serial: stm32: add no_console_suspend support
tty: serial: fsl_lpuart: Use __maybe_unused instead of #if CONFIG_PM_SLEEP
...
fixes.2020.04.27a: Miscellaneous fixes.
kfree_rcu.2020.04.27a: Changes related to kfree_rcu().
rcu-tasks.2020.04.27a: Addition of new RCU-tasks flavors.
stall.2020.04.27a: RCU CPU stall-warning updates.
torture.2020.05.07a: Torture-test updates.
When all quiescent states have been seen, it is normally the grace-period
kthread that is in trouble. Although the existing stack trace from
the current CPU might possibly provide useful information, experience
indicates that there is too much noise for this to be worthwhile.
This commit therefore removes this stack trace from the output.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
If the grace-period kthread is starved, idle threads' extended quiescent
states are not reported. These idle threads thus wrongly appear to
be blocking the current grace period. This commit therefore tags such
idle threads as probable false positives when the grace-period kthread
is being starved.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds state for each RCU-tasks flavor to the rcutorture
writer stall output. The initial state is minimal, but you have to
start somewhere.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
[ paulmck: Fixes based on feedback from kbuild test robot. ]
Currently, an RCU-preempt CPU stall warning simply lists the PIDs of
those tasks holding up the current grace period. This can be helpful,
but more can be even more helpful.
To this end, this commit adds the nesting level, whether the task
thinks it was preempted in its current RCU read-side critical section,
whether RCU core has asked this task for a quiescent state, whether the
expedited-grace-period hint is set, and whether the task believes that
it is on the blocked-tasks list (it must be, or it would not be printed,
but if things are broken, best not to take too much for granted).
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds rcu_gp_might_be_stalled(), which returns true if there
is some reason to believe that the RCU grace period is stalled. The use
case is where an RCU free-memory path needs to allocate memory in order
to free it, a situation that should be avoided where possible.
But where it is necessary, there is always the alternative of using
synchronize_rcu() to wait for a grace period in order to avoid the
allocation. And if the grace period is stalled, allocating memory to
asynchronously wait for it is a bad idea of epic proportions: Far better
to let others use the memory, because these others might actually be
able to free that memory before the grace period ends.
Thus, rcu_gp_might_be_stalled() can be used to help decide whether
allocating memory on an RCU free path is a semi-reasonable course
of action.
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
It is possible that an over-long grace period will end while the RCU
CPU stall warning message is printing. In this case, the estimate of
the offending grace period's duration can be erroneous due to refetching
of rcu_state.gp_start, which will now be the time of the newly started
grace period. Computation of this duration clearly needs to use the
start time for the old over-long grace period, not the fresh new one.
This commit avoids such errors by causing both print_other_cpu_stall() and
print_cpu_stall() to reuse the value previously fetched by their caller.
Signed-off-by: Zhaolong Zhang <zhangzl2013@126.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Although the accesses used to determine whether or not a stall should
be printed are an integral part of the concurrency algorithm governing
use of the corresponding variables, the values that are simply printed
are ancillary. As such, it is best to use data_race() for these accesses
in order to provide the greatest latitude in the use of KCSAN for the
other accesses that are an integral part of the algorithm. This commit
therefore changes the relevant uses of READ_ONCE() to data_race().
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In normal production, an RCU CPU stall warning at boottime is often
just as bad as at any other time. In fact, given the desire for fast
boot, any sort of long-term stall at boot is a bad idea. However,
heavy rcutorture testing on large hyperthreaded systems can generate
boottime RCU CPU stalls as a matter of course. This commit therefore
provides a kernel boot parameter that suppresses reporting of boottime
RCU CPU stall warnings and similarly of rcutorture writer stalls.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently rcu_check_gp_start_stall() complains if a grace period takes
too long to start, where "too long" is roughly one RCU CPU stall-warning
interval. This has worked well, but there are some debugging Kconfig
options (such as CONFIG_EFI_PGT_DUMP=y) that can make booting take a
very long time, so much so that the stall-warning interval has expired
before RCU's grace-period kthread has even been spawned.
This commit therefore resets the rcu_state.gp_req_activity and
rcu_state.gp_activity timestamps just before the grace-period kthread
is spawned, and modifies the checks and adds ordering to ensure that
if rcu_check_gp_start_stall() sees that the grace-period kthread
has been spawned, that it will also see the resets applied to the
rcu_state.gp_req_activity and rcu_state.gp_activity timestamps.
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
[ paulmck: Fix whitespace issues reported by Qian Cai. ]
Tested-by: Qian Cai <cai@lca.pw>
[ paulmck: Simplify grace-period wakeup check per Steve Rostedt feedback. ]
The rcu_state structure's ->gp_start field is read locklessly, so this
commit adds the WRITE_ONCE() to an update in order to provide proper
documentation and READ_ONCE()/WRITE_ONCE() pairing.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_data structure's ->gpwrap field is read locklessly, and so
this commit adds the required READ_ONCE() to a pair of laods in order
to avoid destructive compiler optimizations.
This data race was reported by KCSAN.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The various RCU structures' ->gp_seq, ->gp_seq_needed, ->gp_req_activity,
and ->gp_activity fields are read locklessly, so they must be updated with
WRITE_ONCE() and, when read locklessly, with READ_ONCE(). This commit makes
these changes.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Only tree_stall.h needs to get name from GP state, so this commit
moves the gp_state_names[] array and the gp_state_getname()
from kernel/rcu/tree.h and kernel/rcu/tree.c, respectively, to
kernel/rcu/tree_stall.h. While moving gp_state_names[], this commit
uses the GCC syntax to ensure that the right string is associated with
the right CPP macro.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
CONFIG_PREEMPTION and CONFIG_PREEMPT_RCU are always identical,
but some code depends on CONFIG_PREEMPTION to access to
rcu_preempt functionality. This patch changes CONFIG_PREEMPTION
to CONFIG_PREEMPT_RCU in these cases.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit removes kfree_rcu() special-casing and the lazy-callback
handling from Tree RCU. It moves some of this special casing to Tiny RCU,
the removal of which will be the subject of later commits.
This results in a nice negative delta.
Suggested-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Add slab.h #include, thanks to kbuild test robot <lkp@intel.com>. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Pull scheduler updates from Ingo Molnar:
- MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.
As perf and the scheduler is getting bigger and more complex,
document the status quo of current responsibilities and interests,
and spread the review pain^H^H^H^H fun via an increase in the Cc:
linecount generated by scripts/get_maintainer.pl. :-)
- Add another series of patches that brings the -rt (PREEMPT_RT) tree
closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
into a new CONFIG_PREEMPTION category that will allow the eventual
introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
to go though.
- Extend the CPU cgroup controller with uclamp.min and uclamp.max to
allow the finer shaping of CPU bandwidth usage.
- Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).
- Improve the behavior of high CPU count, high thread count
applications running under cpu.cfs_quota_us constraints.
- Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.
- Improve CPU isolation housekeeping CPU allocation NUMA locality.
- Fix deadline scheduler bandwidth calculations and logic when cpusets
rebuilds the topology, or when it gets deadline-throttled while it's
being offlined.
- Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
setscheduler() system calls without creating global serialization.
Add new synchronization between cpuset topology-changing events and
the deadline acceptance tests in setscheduler(), which were broken
before.
- Rework the active_mm state machine to be less confusing and more
optimal.
- Rework (simplify) the pick_next_task() slowpath.
- Improve load-balancing on AMD EPYC systems.
- ... and misc cleanups, smaller fixes and improvements - please see
the Git log for more details.
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
sched/psi: Correct overly pessimistic size calculation
sched/fair: Speed-up energy-aware wake-ups
sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
sched/uclamp: Update CPU's refcount on TG's clamp changes
sched/uclamp: Use TG's clamps to restrict TASK's clamps
sched/uclamp: Propagate system defaults to the root group
sched/uclamp: Propagate parent clamps
sched/uclamp: Extend CPU's cgroup controller
sched/topology: Improve load balancing on AMD EPYC systems
arch, ia64: Make NUMA select SMP
sched, perf: MAINTAINERS update, add submaintainers and reviewers
sched/fair: Use rq_lock/unlock in online_fair_sched_group
cpufreq: schedutil: fix equation in comment
sched: Rework pick_next_task() slow-path
sched: Allow put_prev_task() to drop rq->lock
sched/fair: Expose newidle_balance()
sched: Add task_struct pointer to sched_class::set_curr_task
sched: Rework CPU hotplug task selection
sched/{rt,deadline}: Fix set_next_task vs pick_next_task
sched: Fix kerneldoc comment for ia64_set_curr_task
...
This commit causes locking, sleeping, and callback state to be printed
for no-CBs CPUs when the rcutorture writer is delayed sufficiently for
rcutorture to complain.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adds a rcu_cpu_stall_ftrace_dump kernel boot parameter, that,
when set, causes the trace buffer to be dumped after an RCU CPU stall
warning is printed. This kernel boot parameter is disabled by default,
maintaining compatibility with previous behavior.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
On systems whose rcu_node tree has only one node, the
rcu_check_gp_start_stall() function's values of rnp and rnp_root will
be identical. In this case, it clearly does not make sense to release
both rnp->lock and rnp_root->lock, but that is exactly what this function
does in the last early exit. This commit therefore unlocks only rnp->lock
when rnp and rnp_root are equal.
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The Documentation/RCU/stallwarn.txt file says that stall warnings
print "D" if dyntick-idle processing is enabled, but the code in
print_cpu_stall_fast_no_hz() prints "." instead. This commit therefore
reverses the sense of the test to make the code match the documentation.
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit further consolidates stall-warning functionality by moving
forward-progress checkers into kernel/rcu/tree_stall.h, updating a
comment or two while in the area. More specifically, this commit moves
show_rcu_gp_kthreads(), rcu_check_gp_start_stall(), rcu_fwd_progress_check(),
sysrq_rcu, sysrq_show_rcu(), sysrq_rcudump_op, and rcu_sysrq_init() from
kernel/rcu/tree.c to kernel/rcu/tree_stall.h.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The rcu_iw_handler() function's sole purpose in life is to indicate
whether a stalled CPU had interrupts disabled, so it belongs in
kernel/rcu/tree_stall.h. This commit therefore makes that move,
clarifying its header comment while in the area.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit does only code movement, removal of now-unneeded forward
declarations, and addition of comments. It organizes the functions
that implement RCU CPU stall warnings for normal grace periods into
three categories:
1. Control of RCU CPU stall warnings, including computing timeouts.
2. Interaction of stall warnings with grace periods.
3. Actual printing of the RCU CPU stall-warning messages.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit further consolidates the stall-warning code by moving
print_cpu_stall_info() and its helper functions along with
zero_cpu_stall_ticks() to kernel/rcu/tree_stall.h.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The print_cpu_stall_info_begin() and print_cpu_stall_info_end() print a
single character each onto the console, and are a holdover from a time
when RCU CPU stall warning messages could be abbreviated using a long-gone
Kconfig option. This commit therefore adds these single characters to
already-printed strings in the calling functions, and then eliminates
both print_cpu_stall_info_begin() and print_cpu_stall_info_end().
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The rcu_print_detail_task_stall(), rcu_print_task_stall_begin(), and
rcu_print_task_stall_end() functions were defined to allow long-gone
Kconfig options to provide an abbreviated RCU CPU stall warning printout.
This commit saves a few lines of code by inlining them into their sole
callers.
While in the area, a useless call of rcu_print_detail_task_stall_rnp()
on the root rcu_node structure was eliminated. If there is only one
rcu_node structure, its tasks get printed twice, but if there are more,
the root rcu_node structure is guaranteed to have an empty list of blocked
tasks, hence the uselessness. (Long ago, root rcu_node structures with
non-empty ->blkd_tasks lists could happen, but no longer.)
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit completes the process of consolidating the code for RCU CPU
stall warnings for normal grace periods by moving the remaining such
code from kernel/rcu/tree.c to kernel/rcu/tree_stall.h.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The RCU CPU stall-warning code for normal grace periods is currently
scattered across two files, due to earlier Tiny RCU support for RCU
CPU stall warnings and for old Kconfig options that have long since
been retired. Given that it is hard for the lead RCU maintainer to
find relevant stall-warning code, it would be good to consolidate it.
This commit continues this process by moving stall-warning code from
kernel/rcu/tree_plugin.c to a new kernel/rcu/tree_stall.h file.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The RCU CPU stall-warning code for normal grace periods is currently
scattered across three files, due to earlier Tiny RCU support for RCU
CPU stall warnings and for old Kconfig options that have long since
been retired. Given that it is hard for the lead RCU maintainer to
find relevant stall-warning code, it would be good to consolidate it.
This commit starts this process by moving stall-warning code from
kernel/rcu/update.c to a new kernel/rcu/tree_stall.h file.
Note that the definitions of rcu_cpu_stall_suppress and
rcu_cpu_stall_timeout must remain in kernel/rcu/update.h to provide
compatibility for kernel boot parameter lists.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
