* linux-linaro-lsk-v4.4: (361 commits)
Linux 4.4.135
Revert "vti4: Don't override MTU passed on link creation via IFLA_MTU"
Linux 4.4.134
s390/ftrace: use expoline for indirect branches
kdb: make "mdr" command repeat
Bluetooth: btusb: Add device ID for RTL8822BE
ASoC: samsung: i2s: Ensure the RCLK rate is properly determined
regulator: of: Add a missing 'of_node_put()' in an error handling path of 'of_regulator_match()'
scsi: lpfc: Fix frequency of Release WQE CQEs
scsi: lpfc: Fix soft lockup in lpfc worker thread during LIP testing
scsi: lpfc: Fix issue_lip if link is disabled
netlabel: If PF_INET6, check sk_buff ip header version
selftests/net: fixes psock_fanout eBPF test case
perf report: Fix memory corruption in --branch-history mode --branch-history
perf tests: Use arch__compare_symbol_names to compare symbols
x86/apic: Set up through-local-APIC mode on the boot CPU if 'noapic' specified
drm/rockchip: Respect page offset for PRIME mmap calls
MIPS: Octeon: Fix logging messages with spurious periods after newlines
audit: return on memory error to avoid null pointer dereference
crypto: sunxi-ss - Add MODULE_ALIAS to sun4i-ss
...
Conflicts:
arch/arm64/include/asm/assembler.h
Rebase LTS commit 348f043ab6
("arm64: Add work around for Arm Cortex-A55 Erratum 1024718").
fs/f2fs/namei.c
Rebase LTS commit 03bb758894
("do d_instantiate/unlock_new_inode combinations safely")
fs/proc/base.c
Trivial typo.
kernel/auditsc.c
Rebase LTS commit 9bb698bede
("audit: move calcs after alloc and check when logging set loginuid").
kernel/time/timekeeping.c
Rebase changes from AOSP commit 28850c79d0
("BACKPORT: time: Fix CLOCK_MONOTONIC_RAW sub-nanosecond accounting"), and
1d35c04386 ("BACKPORT: time: Clean up CLOCK_MONOTONIC_RAW time handling").
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
LSK 18.05 v4.4-android
* tag 'lsk-v4.4-18.05-android': (605 commits)
ANDROID: sdcardfs: Don't d_drop in d_revalidate
goldfish: pipe: ANDROID: mark local functions static
UPSTREAM: ANDROID: binder: prevent transactions into own process.
goldfish: pipe: ANDROID: Add DMA support
UPSTREAM: f2fs: clear PageError on writepage - part 2
UPSTREAM: f2fs: avoid fsync() failure caused by EAGAIN in writepage()
ANDROID: x86_64_cuttlefish_defconfig: Disable KPTI
UPSTREAM: mac80211: ibss: Fix channel type enum in ieee80211_sta_join_ibss()
UPSTREAM: mac80211: Fix clang warning about constant operand in logical operation
UPSTREAM: nl80211: Fix enum type of variable in nl80211_put_sta_rate()
UPSTREAM: sysfs: remove signedness from sysfs_get_dirent
UPSTREAM: tracing: Use cpumask_available() to check if cpumask variable may be used
BACKPORT: clocksource: Use GENMASK_ULL in definition of CLOCKSOURCE_MASK
UPSTREAM: netpoll: Fix device name check in netpoll_setup()
FROMLIST: staging: Fix sparse warnings in vsoc driver.
FROMLIST: staging: vsoc: Fix a i386-randconfig warning.
FROMLIST: staging: vsoc: Create wc kernel mapping for region shm.
goldfish: pipe: ANDROID: Replace writel with gf_write_ptr
goldfish: pipe: ANDROID: Use dev_ logging instead of pr_
goldfish: pipe: ANDROID: fix checkpatch warnings
...
Conflicts:
fs/f2fs/node.c
scripts/Makefile.lib
Change-Id: Ib92d11938a383464249fe6f2dad3ab2a05bc4770
commit 3d88d56c58 upstream.
Due to how the MONOTONIC_RAW accumulation logic was handled,
there is the potential for a 1ns discontinuity when we do
accumulations. This small discontinuity has for the most part
gone un-noticed, but since ARM64 enabled CLOCK_MONOTONIC_RAW
in their vDSO clock_gettime implementation, we've seen failures
with the inconsistency-check test in kselftest.
This patch addresses the issue by using the same sub-ns
accumulation handling that CLOCK_MONOTONIC uses, which avoids
the issue for in-kernel users.
Since the ARM64 vDSO implementation has its own clock_gettime
calculation logic, this patch reduces the frequency of errors,
but failures are still seen. The ARM64 vDSO will need to be
updated to include the sub-nanosecond xtime_nsec values in its
calculation for this issue to be completely fixed.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Daniel Mentz <danielmentz@google.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: "stable #4 . 8+" <stable@vger.kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: http://lkml.kernel.org/r/1496965462-20003-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[fabrizio: cherry-pick to 4.4. Kept cycle_t type for function
logarithmic_accumulation local variable "interval". Dropped
casting of "interval" variable]
Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hrtimer_init_on_stack() needs a matching call to
destroy_hrtimer_on_stack(), so both need to be exported.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit c08376ac97)
[astrachan: Fixes i386-allmodconfig build failure in vsoc.ko noticed
by 01.org kbuild-all project building kernel/msm]
Bug: 78036828
Change-Id: If4d5c466255019322ea21ef38ee5b1b382cce969
Signed-off-by: Alistair Strachan <astrachan@google.com>
* linux-linaro-lsk-v4.4-android: (395 commits)
Linux 4.4.126
net: systemport: Rewrite __bcm_sysport_tx_reclaim()
net: fec: Fix unbalanced PM runtime calls
ieee802154: 6lowpan: fix possible NULL deref in lowpan_device_event()
s390/qeth: on channel error, reject further cmd requests
s390/qeth: lock read device while queueing next buffer
s390/qeth: when thread completes, wake up all waiters
s390/qeth: free netdevice when removing a card
team: Fix double free in error path
skbuff: Fix not waking applications when errors are enqueued
net: Only honor ifindex in IP_PKTINFO if non-0
netlink: avoid a double skb free in genlmsg_mcast()
net/iucv: Free memory obtained by kzalloc
net: ethernet: ti: cpsw: add check for in-band mode setting with RGMII PHY interface
net: ethernet: arc: Fix a potential memory leak if an optional regulator is deferred
l2tp: do not accept arbitrary sockets
ipv6: fix access to non-linear packet in ndisc_fill_redirect_hdr_option()
dccp: check sk for closed state in dccp_sendmsg()
net: Fix hlist corruptions in inet_evict_bucket()
Revert "genirq: Use irqd_get_trigger_type to compare the trigger type for shared IRQs"
...
Conflicts:
include/linux/usb/quirks.h
Change-Id: I125065cef66846e4cdee799f4b34d07c309d353e
[ Upstream commit 0107042768 ]
On systems with a large number of CPUs, running sysrq-<q> can cause
watchdog timeouts. There are two slow sections of code in the sysrq-<q>
path in timer_list.c.
1. print_active_timers() - This function is called by print_cpu() and
contains a slow goto loop. On a machine with hundreds of CPUs, this
loop took approximately 100ms for the first CPU in a NUMA node.
(Subsequent CPUs in the same node ran much quicker.) The total time
to print all of the CPUs is ultimately long enough to trigger the
soft lockup watchdog.
2. print_tickdevice() - This function outputs a large amount of textual
information. This function also took approximately 100ms per CPU.
Since sysrq-<q> is not a performance critical path, there should be no
harm in touching the nmi watchdog in both slow sections above. Touching
it in just one location was insufficient on systems with hundreds of
CPUs as occasional timeouts were still observed during testing.
This issue was observed on an Oracle T7 machine with 128 CPUs, but I
anticipate it may affect other systems with similarly large numbers of
CPUs.
Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>
Reviewed-by: Rob Gardner <rob.gardner@oracle.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1b8955bc5a ]
The scheduler clock framework may not use the correct timeout for the clock
wrap. This happens when a new clock driver calls sched_clock_register()
after the kernel called sched_clock_postinit(). In this case the clock wrap
timeout is too long thus sched_clock_poll() is called too late and the clock
already wrapped.
On my ARM system the scheduler was no longer scheduling any other task than
the idle task because the sched_clock() wrapped.
Signed-off-by: David Engraf <david.engraf@sysgo.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In comqit fc6eead7c1 ("time: Clean up CLOCK_MONOTONIC_RAW time
handling"), the following code got mistakenly added to the update of the
raw timekeeper:
/* Update the monotonic raw base */
seconds = tk->raw_sec;
nsec = (u32)(tk->tkr_raw.xtime_nsec >> tk->tkr_raw.shift);
tk->tkr_raw.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
Which adds the raw_sec value and the shifted down raw xtime_nsec to the
base value.
But the read function adds the shifted down tk->tkr_raw.xtime_nsec value
another time, The result of this is that ktime_get_raw() users (which are
all internal users) see the raw time move faster then it should (the rate
at which can vary with the current size of tkr_raw.xtime_nsec), which has
resulted in at least problems with graphics rendering performance.
The change tried to match the monotonic base update logic:
seconds = (u64)(tk->xtime_sec + tk->wall_to_monotonic.tv_sec);
nsec = (u32) tk->wall_to_monotonic.tv_nsec;
tk->tkr_mono.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
Which adds the wall_to_monotonic.tv_nsec value, but not the
tk->tkr_mono.xtime_nsec value to the base.
To fix this, simplify the tkr_raw.base accumulation to only accumulate the
raw_sec portion, and do not include the tkr_raw.xtime_nsec portion, which
will be added at read time.
Fixes: fc6eead7c1 ("time: Clean up CLOCK_MONOTONIC_RAW time handling")
Reported-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Daniel Mentz <danielmentz@google.com>
Link: http://lkml.kernel.org/r/1503701824-1645-1-git-send-email-john.stultz@linaro.org
(cherry picked from commit 0bcdc0987c)
Change-Id: I91d552bef42005d954f77963beafdca3cb6eb246
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Conflicts:
fs/f2fs/extent_cache.c
Pick changes from AOSP Change-Id: Icd8a85ac0c19a8aa25cd2591a12b4e9b85bdf1c5
("f2fs: catch up to v4.14-rc1")
fs/f2fs/namei.c
Pick changes from AOSP F2FS backport commit 7d5c08fd91
("f2fs: backport from (4c1fad64 - Merge tag 'for-f2fs-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs)")
commit cef31d9af9 upstream.
timer_create() specifies via sigevent->sigev_notify the signal delivery for
the new timer. The valid modes are SIGEV_NONE, SIGEV_SIGNAL, SIGEV_THREAD
and (SIGEV_SIGNAL | SIGEV_THREAD_ID).
The sanity check in good_sigevent() is only checking the valid combination
for the SIGEV_THREAD_ID bit, i.e. SIGEV_SIGNAL, but if SIGEV_THREAD_ID is
not set it accepts any random value.
This has no real effects on the posix timer and signal delivery code, but
it affects show_timer() which handles the output of /proc/$PID/timers. That
function uses a string array to pretty print sigev_notify. The access to
that array has no bound checks, so random sigev_notify cause access beyond
the array bounds.
Add proper checks for the valid notify modes and remove the SIGEV_THREAD_ID
masking from various code pathes as SIGEV_NONE can never be set in
combination with SIGEV_THREAD_ID.
Reported-by: Eric Biggers <ebiggers3@gmail.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
LSK 18.02 v4.4-android
* tag 'lsk-v4.4-18.02-android': (131 commits)
Linux 4.4.114
nfsd: auth: Fix gid sorting when rootsquash enabled
net: tcp: close sock if net namespace is exiting
flow_dissector: properly cap thoff field
ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY
net: Allow neigh contructor functions ability to modify the primary_key
vmxnet3: repair memory leak
sctp: return error if the asoc has been peeled off in sctp_wait_for_sndbuf
sctp: do not allow the v4 socket to bind a v4mapped v6 address
r8169: fix memory corruption on retrieval of hardware statistics.
pppoe: take ->needed_headroom of lower device into account on xmit
net: qdisc_pkt_len_init() should be more robust
tcp: __tcp_hdrlen() helper
net: igmp: fix source address check for IGMPv3 reports
lan78xx: Fix failure in USB Full Speed
ipv6: ip6_make_skb() needs to clear cork.base.dst
ipv6: fix udpv6 sendmsg crash caused by too small MTU
ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABEL
dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
hrtimer: Reset hrtimer cpu base proper on CPU hotplug
...
commit d5421ea43d upstream.
The hrtimer interrupt code contains a hang detection and mitigation
mechanism, which prevents that a long delayed hrtimer interrupt causes a
continous retriggering of interrupts which prevent the system from making
progress. If a hang is detected then the timer hardware is programmed with
a certain delay into the future and a flag is set in the hrtimer cpu base
which prevents newly enqueued timers from reprogramming the timer hardware
prior to the chosen delay. The subsequent hrtimer interrupt after the delay
clears the flag and resumes normal operation.
If such a hang happens in the last hrtimer interrupt before a CPU is
unplugged then the hang_detected flag is set and stays that way when the
CPU is plugged in again. At that point the timer hardware is not armed and
it cannot be armed because the hang_detected flag is still active, so
nothing clears that flag. As a consequence the CPU does not receive hrtimer
interrupts and no timers expire on that CPU which results in RCU stalls and
other malfunctions.
Clear the flag along with some other less critical members of the hrtimer
cpu base to ensure starting from a clean state when a CPU is plugged in.
Thanks to Paul, Sebastian and Anna-Maria for their help to get down to the
root cause of that hard to reproduce heisenbug. Once understood it's
trivial and certainly justifies a brown paperbag.
Fixes: 41d2e49493 ("hrtimer: Tune hrtimer_interrupt hang logic")
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Sewior <bigeasy@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801261447590.2067@nanos
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry pick from commit 3d88d56c58)
Due to how the MONOTONIC_RAW accumulation logic was handled,
there is the potential for a 1ns discontinuity when we do
accumulations. This small discontinuity has for the most part
gone un-noticed, but since ARM64 enabled CLOCK_MONOTONIC_RAW
in their vDSO clock_gettime implementation, we've seen failures
with the inconsistency-check test in kselftest.
This patch addresses the issue by using the same sub-ns
accumulation handling that CLOCK_MONOTONIC uses, which avoids
the issue for in-kernel users.
Since the ARM64 vDSO implementation has its own clock_gettime
calculation logic, this patch reduces the frequency of errors,
but failures are still seen. The ARM64 vDSO will need to be
updated to include the sub-nanosecond xtime_nsec values in its
calculation for this issue to be completely fixed.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Daniel Mentz <danielmentz@google.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: "stable #4 . 8+" <stable@vger.kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: http://lkml.kernel.org/r/1496965462-20003-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Bug: 20045882
Bug: 63737556
Change-Id: I6c55dd7685f6bd212c6af9d09c527528e1dd5fa1
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Conflicts:
kernel/fork.c
Conflict due to Kaiser implementation in LTS 4.4.110.
net/ipv4/raw.c
Minor conflict due to LTS commit
be27b620a8 ("net: ipv4: fix for a race condition in raw_sendmsg")
commit 5d62c183f9 upstream.
The conditions in irq_exit() to invoke tick_nohz_irq_exit() which
subsequently invokes tick_nohz_stop_sched_tick() are:
if ((idle_cpu(cpu) && !need_resched()) || tick_nohz_full_cpu(cpu))
If need_resched() is not set, but a timer softirq is pending then this is
an indication that the softirq code punted and delegated the execution to
softirqd. need_resched() is not true because the current interrupted task
takes precedence over softirqd.
Invoking tick_nohz_irq_exit() in this case can cause an endless loop of
timer interrupts because the timer wheel contains an expired timer, but
softirqs are not yet executed. So it returns an immediate expiry request,
which causes the timer to fire immediately again. Lather, rinse and
repeat....
Prevent that by adding a check for a pending timer soft interrupt to the
conditions in tick_nohz_stop_sched_tick() which avoid calling
get_next_timer_interrupt(). That keeps the tick sched timer on the tick and
prevents a repetitive programming of an already expired timer.
Reported-by: Sebastian Siewior <bigeasy@linutronix.d>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712272156050.2431@nanos
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3d88d56c58 upstream.
Due to how the MONOTONIC_RAW accumulation logic was handled,
there is the potential for a 1ns discontinuity when we do
accumulations. This small discontinuity has for the most part
gone un-noticed, but since ARM64 enabled CLOCK_MONOTONIC_RAW
in their vDSO clock_gettime implementation, we've seen failures
with the inconsistency-check test in kselftest.
This patch addresses the issue by using the same sub-ns
accumulation handling that CLOCK_MONOTONIC uses, which avoids
the issue for in-kernel users.
Since the ARM64 vDSO implementation has its own clock_gettime
calculation logic, this patch reduces the frequency of errors,
but failures are still seen. The ARM64 vDSO will need to be
updated to include the sub-nanosecond xtime_nsec values in its
calculation for this issue to be completely fixed.
Change-Id: I84f455fc9adbb26c4130205d9ebe3683f638fc1d
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Daniel Mentz <danielmentz@google.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: http://lkml.kernel.org/r/1496965462-20003-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tao Huang <huangtao@rock-chips.com>
(cherry picked from LTS linux-4.9.y
commit a53bfdda06)
LSK 17.08 v4.4-android
* tag 'lsk-v4.4-17.08-android': (451 commits)
Linux 4.4.83
pinctrl: samsung: Remove bogus irq_[un]mask from resource management
pinctrl: sunxi: add a missing function of A10/A20 pinctrl driver
pnfs/blocklayout: require 64-bit sector_t
iio: adc: vf610_adc: Fix VALT selection value for REFSEL bits
usb:xhci:Add quirk for Certain failing HP keyboard on reset after resume
usb: quirks: Add no-lpm quirk for Moshi USB to Ethernet Adapter
usb: core: unlink urbs from the tail of the endpoint's urb_list
USB: Check for dropped connection before switching to full speed
uag: Add US_FL_IGNORE_RESIDUE for Initio Corporation INIC-3069
iio: light: tsl2563: use correct event code
iio: accel: bmc150: Always restore device to normal mode after suspend-resume
staging:iio:resolver:ad2s1210 fix negative IIO_ANGL_VEL read
USB: hcd: Mark secondary HCD as dead if the primary one died
usb: musb: fix tx fifo flush handling again
USB: serial: pl2303: add new ATEN device id
USB: serial: cp210x: add support for Qivicon USB ZigBee dongle
USB: serial: option: add D-Link DWM-222 device ID
nfs/flexfiles: fix leak of nfs4_ff_ds_version arrays
fuse: initialize the flock flag in fuse_file on allocation
...
The way the schedutil governor uses the PELT metric causes it to
underestimate the CPU utilization in some cases.
That can be easily demonstrated by running kernel compilation on
a Sandy Bridge Intel processor, running turbostat in parallel with
it and looking at the values written to the MSR_IA32_PERF_CTL
register. Namely, the expected result would be that when all CPUs
were 100% busy, all of them would be requested to run in the maximum
P-state, but observation shows that this clearly isn't the case.
The CPUs run in the maximum P-state for a while and then are
requested to run slower and go back to the maximum P-state after
a while again. That causes the actual frequency of the processor to
visibly oscillate below the sustainable maximum in a jittery fashion
which clearly is not desirable.
That has been attributed to CPU utilization metric updates on task
migration that cause the total utilization value for the CPU to be
reduced by the utilization of the migrated task. If that happens,
the schedutil governor may see a CPU utilization reduction and will
attempt to reduce the CPU frequency accordingly right away. That
may be premature, though, for example if the system is generally
busy and there are other runnable tasks waiting to be run on that
CPU already.
This is unlikely to be an issue on systems where cpufreq policies are
shared between multiple CPUs, because in those cases the policy
utilization is computed as the maximum of the CPU utilization values
over the whole policy and if that turns out to be low, reducing the
frequency for the policy most likely is a good idea anyway. On
systems with one CPU per policy, however, it may affect performance
adversely and even lead to increased energy consumption in some cases.
On those systems it may be addressed by taking another utilization
metric into consideration, like whether or not the CPU whose
frequency is about to be reduced has been idle recently, because if
that's not the case, the CPU is likely to be busy in the near future
and its frequency should not be reduced.
To that end, use the counter of idle calls in the timekeeping code.
Namely, make the schedutil governor look at that counter for the
current CPU every time before its frequency is about to be reduced.
If the counter has not changed since the previous iteration of the
governor computations for that CPU, the CPU has been busy for all
that time and its frequency should not be decreased, so if the new
frequency would be lower than the one set previously, the governor
will skip the frequency update.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Joel Fernandes <joelaf@google.com>
(cherry picked from commit b7eaf1aab9)
(simple CPUFREQ_RT_DL vs CPUFREQ_DL usage conflicts)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Change-Id: I531ec02c052944ee07a904dc2a25c59948ee762b
LSK 17.07 v4.4-android
* tag 'lsk-v4.4-17.07-android': (402 commits)
dt/vendor-prefixes: remove redundant vendor
Linux 4.4.77
saa7134: fix warm Medion 7134 EEPROM read
x86/mm/pat: Don't report PAT on CPUs that don't support it
ext4: check return value of kstrtoull correctly in reserved_clusters_store
staging: comedi: fix clean-up of comedi_class in comedi_init()
staging: vt6556: vnt_start Fix missing call to vnt_key_init_table.
tcp: fix tcp_mark_head_lost to check skb len before fragmenting
md: fix super_offset endianness in super_1_rdev_size_change
md: fix incorrect use of lexx_to_cpu in does_sb_need_changing
perf tools: Use readdir() instead of deprecated readdir_r() again
perf tests: Remove wrong semicolon in while loop in CQM test
perf trace: Do not process PERF_RECORD_LOST twice
perf dwarf: Guard !x86_64 definitions under #ifdef else clause
perf pmu: Fix misleadingly indented assignment (whitespace)
perf annotate browser: Fix behaviour of Shift-Tab with nothing focussed
perf tools: Remove duplicate const qualifier
perf script: Use readdir() instead of deprecated readdir_r()
perf thread_map: Use readdir() instead of deprecated readdir_r()
perf tools: Use readdir() instead of deprecated readdir_r()
...
Conflicts:
Makefile
drivers/Kconfig
drivers/Makefile
drivers/usb/dwc3/gadget.c
Change-Id: Ib4aae2e34ebbf0d7953c748a33f673acb3e744fc
commit ceea5e3771 upstream.
In tests, which excercise switching of clocksources, a NULL
pointer dereference can be observed on AMR64 platforms in the
clocksource read() function:
u64 clocksource_mmio_readl_down(struct clocksource *c)
{
return ~(u64)readl_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
}
This is called from the core timekeeping code via:
cycle_now = tkr->read(tkr->clock);
tkr->read is the cached tkr->clock->read() function pointer.
When the clocksource is changed then tkr->clock and tkr->read
are updated sequentially. The code above results in a sequential
load operation of tkr->read and tkr->clock as well.
If the store to tkr->clock hits between the loads of tkr->read
and tkr->clock, then the old read() function is called with the
new clock pointer. As a consequence the read() function
dereferences a different data structure and the resulting 'reg'
pointer can point anywhere including NULL.
This problem was introduced when the timekeeping code was
switched over to use struct tk_read_base. Before that, it was
theoretically possible as well when the compiler decided to
reload clock in the code sequence:
now = tk->clock->read(tk->clock);
Add a helper function which avoids the issue by reading
tk_read_base->clock once into a local variable clk and then issue
the read function via clk->read(clk). This guarantees that the
read() function always gets the proper clocksource pointer handed
in.
Since there is now no use for the tkr.read pointer, this patch
also removes it, and to address stopping the fast timekeeper
during suspend/resume, it introduces a dummy clocksource to use
rather then just a dummy read function.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Daniel Mentz <danielmentz@google.com>
Link: http://lkml.kernel.org/r/1496965462-20003-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ff86bf0c65 upstream.
The alarmtimer code has another source of potentially rearming itself too
fast. Interval timers with a very samll interval have a similar CPU hog
effect as the previously fixed overflow issue.
The reason is that alarmtimers do not implement the normal protection
against this kind of problem which the other posix timer use:
timer expires -> queue signal -> deliver signal -> rearm timer
This scheme brings the rearming under scheduler control and prevents
permanently firing timers which hog the CPU.
Bringing this scheme to the alarm timer code is a major overhaul because it
lacks all the necessary mechanisms completely.
So for a quick fix limit the interval to one jiffie. This is not
problematic in practice as alarmtimers are usually backed by an RTC for
suspend which have 1 second resolution. It could be therefor argued that
the resolution of this clock should be set to 1 second in general, but
that's outside the scope of this fix.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kostya Serebryany <kcc@google.com>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/r/20170530211655.896767100@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f4781e76f9 upstream.
Andrey reported a alartimer related RCU stall while fuzzing the kernel with
syzkaller.
The reason for this is an overflow in ktime_add() which brings the
resulting time into negative space and causes immediate expiry of the
timer. The following rearm with a small interval does not bring the timer
back into positive space due to the same issue.
This results in a permanent firing alarmtimer which hogs the CPU.
Use ktime_add_safe() instead which detects the overflow and clamps the
result to KTIME_SEC_MAX.
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kostya Serebryany <kcc@google.com>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/r/20170530211655.802921648@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* linux-linaro-lsk-v4.4-android: (199 commits)
Linux 4.4.41
net: mvpp2: fix dma unmapping of TX buffers for fragments
sg_write()/bsg_write() is not fit to be called under KERNEL_DS
kconfig/nconf: Fix hang when editing symbol with a long prompt
target/user: Fix use-after-free of tcmu_cmds if they are expired
powerpc: Convert cmp to cmpd in idle enter sequence
powerpc/ps3: Fix system hang with GCC 5 builds
nfs_write_end(): fix handling of short copies
libceph: verify authorize reply on connect
PCI: Check for PME in targeted sleep state
Input: drv260x - fix input device's parent assignment
media: solo6x10: fix lockup by avoiding delayed register write
IB/cma: Fix a race condition in iboe_addr_get_sgid()
IB/multicast: Check ib_find_pkey() return value
IPoIB: Avoid reading an uninitialized member variable
IB/mad: Fix an array index check
fgraph: Handle a case where a tracer ignores set_graph_notrace
platform/x86: asus-nb-wmi.c: Add X45U quirk
ftrace/x86_32: Set ftrace_stub to weak to prevent gcc from using short jumps to it
kvm: nVMX: Allow L1 to intercept software exceptions (#BP and #OF)
...
Change-Id: I8c8467700d5563d9a1121c982737ff0ab6d9cdc9
commit 9c1645727b upstream.
The clocksource delta to nanoseconds conversion is using signed math, but
the delta is unsigned. This makes the conversion space smaller than
necessary and in case of a multiplication overflow the conversion can
become negative. The conversion is done with scaled math:
s64 nsec_delta = ((s64)clkdelta * clk->mult) >> clk->shift;
Shifting a signed integer right obvioulsy preserves the sign, which has
interesting consequences:
- Time jumps backwards
- __iter_div_u64_rem() which is used in one of the calling code pathes
will take forever to piecewise calculate the seconds/nanoseconds part.
This has been reported by several people with different scenarios:
David observed that when stopping a VM with a debugger:
"It was essentially the stopped by debugger case. I forget exactly why,
but the guest was being explicitly stopped from outside, it wasn't just
scheduling lag. I think it was something in the vicinity of 10 minutes
stopped."
When lifting the stop the machine went dead.
The stopped by debugger case is not really interesting, but nevertheless it
would be a good thing not to die completely.
But this was also observed on a live system by Liav:
"When the OS is too overloaded, delta will get a high enough value for the
msb of the sum delta * tkr->mult + tkr->xtime_nsec to be set, and so
after the shift the nsec variable will gain a value similar to
0xffffffffff000000."
Unfortunately this has been reintroduced recently with commit 6bd58f09e1
("time: Add cycles to nanoseconds translation"). It had been fixed a year
ago already in commit 35a4933a89 ("time: Avoid signed overflow in
timekeeping_get_ns()").
Though it's not surprising that the issue has been reintroduced because the
function itself and the whole call chain uses s64 for the result and the
propagation of it. The change in this recent commit is subtle:
s64 nsec;
- nsec = (d * m + n) >> s:
+ nsec = d * m + n;
+ nsec >>= s;
d being type of cycle_t adds another level of obfuscation.
This wouldn't have happened if the previous change to unsigned computation
would have made the 'nsec' variable u64 right away and a follow up patch
had cleaned up the whole call chain.
There have been patches submitted which basically did a revert of the above
patch leaving everything else unchanged as signed. Back to square one. This
spawned a admittedly pointless discussion about potential users which rely
on the unsigned behaviour until someone pointed out that it had been fixed
before. The changelogs of said patches added further confusion as they made
finally false claims about the consequences for eventual users which expect
signed results.
Despite delta being cycle_t, aka. u64, it's very well possible to hand in
a signed negative value and the signed computation will happily return the
correct result. But nobody actually sat down and analyzed the code which
was added as user after the propably unintended signed conversion.
Though in sensitive code like this it's better to analyze it proper and
make sure that nothing relies on this than hunting the subtle wreckage half
a year later. After analyzing all call chains it stands that no caller can
hand in a negative value (which actually would work due to the s64 cast)
and rely on the signed math to do the right thing.
Change the conversion function to unsigned math. The conversion of all call
chains is done in a follow up patch.
This solves the starvation issue, which was caused by the negative result,
but it does not solve the underlying problem. It merily procrastinates
it. When the timekeeper update is deferred long enough that the unsigned
multiplication overflows, then time going backwards is observable again.
It does neither solve the issue of clocksources with a small counter width
which will wrap around possibly several times and cause random time stamps
to be generated. But those are usually not found on systems used for
virtualization, so this is likely a non issue.
I took the liberty to claim authorship for this simply because
analyzing all callsites and writing the changelog took substantially
more time than just making the simple s/s64/u64/ change and ignore the
rest.
Fixes: 6bd58f09e1 ("time: Add cycles to nanoseconds translation")
Reported-by: David Gibson <david@gibson.dropbear.id.au>
Reported-by: Liav Rehana <liavr@mellanox.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Parit Bhargava <prarit@redhat.com>
Cc: Laurent Vivier <lvivier@redhat.com>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20161208204228.688545601@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* linux-linaro-lsk-v4.4-android: (61 commits)
Linux 4.4.36
scsi: mpt3sas: Unblock device after controller reset
flow_dissect: call init_default_flow_dissectors() earlier
mei: fix return value on disconnection
mei: me: fix place for kaby point device ids.
mei: me: disable driver on SPT SPS firmware
drm/radeon: Ensure vblank interrupt is enabled on DPMS transition to on
mpi: Fix NULL ptr dereference in mpi_powm() [ver #3]
parisc: Also flush data TLB in flush_icache_page_asm
parisc: Fix race in pci-dma.c
parisc: Fix races in parisc_setup_cache_timing()
NFSv4.x: hide array-bounds warning
apparmor: fix change_hat not finding hat after policy replacement
cfg80211: limit scan results cache size
tile: avoid using clocksource_cyc2ns with absolute cycle count
scsi: mpt3sas: Fix secure erase premature termination
Fix USB CB/CBI storage devices with CONFIG_VMAP_STACK=y
USB: serial: ftdi_sio: add support for TI CC3200 LaunchPad
USB: serial: cp210x: add ID for the Zone DPMX
usb: chipidea: move the lock initialization to core file
...
This boot clock can be used as a tracing clock and will account for
suspend time.
To keep it NMI safe since we're accessing from tracing, we're not using a
separate timekeeper with updates to monotonic clock and boot offset
protected with seqlocks. This has the following minor side effects:
(1) Its possible that a timestamp be taken after the boot offset is updated
but before the timekeeper is updated. If this happens, the new boot offset
is added to the old timekeeping making the clock appear to update slightly
earlier:
CPU 0 CPU 1
timekeeping_inject_sleeptime64()
__timekeeping_inject_sleeptime(tk, delta);
timestamp();
timekeeping_update(tk, TK_CLEAR_NTP...);
(2) On 32-bit systems, the 64-bit boot offset (tk->offs_boot) may be
partially updated. Since the tk->offs_boot update is a rare event, this
should be a rare occurrence which postprocessing should be able to handle.
Bug: b/33184060
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
* linux-linaro-lsk-v4.4-android: (1362 commits)
Linux 4.4.30
Revert "fix minor infoleak in get_user_ex()"
Revert "x86/mm: Expand the exception table logic to allow new handling options"
Linux 4.4.29
ARM: pxa: pxa_cplds: fix interrupt handling
powerpc/nvram: Fix an incorrect partition merge
mpt3sas: Don't spam logs if logging level is 0
perf symbols: Fixup symbol sizes before picking best ones
perf symbols: Check symbol_conf.allow_aliases for kallsyms loading too
perf hists browser: Fix event group display
clk: divider: Fix clk_divider_round_rate() to use clk_readl()
clk: qoriq: fix a register offset error
s390/con3270: fix insufficient space padding
s390/con3270: fix use of uninitialised data
s390/cio: fix accidental interrupt enabling during resume
x86/mm: Expand the exception table logic to allow new handling options
dmaengine: ipu: remove bogus NO_IRQ reference
power: bq24257: Fix use of uninitialized pointer bq->charger
staging: r8188eu: Fix scheduling while atomic splat
ASoC: dapm: Fix kcontrol creation for output driver widget
...
