Pull hyperv updates from Wei Liu:
- Decrypt netvsc buffer on contiguous direct-map addresses (Kameron
Carr)
- Drop WS2012/2012R2 & Win8/8.1 Hyper-V support (Michael Kelley)
- Use more meaningful errnos for hypercall status code (Hardik Garg)
- Fix lost interrupts on CPU hot-unplug for Hyper-V PCI/MSI (Naman
Jain)
- Reserve more MSHV vectors for Linux root partition (Wei Liu)
* tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
clocksource: hyper-v: Remove support for stimer interrupts in message mode
scsi: storvsc: Remove support for storvsc protocol of old Hyper-V hosts
hv_netvsc: Remove GPADL teardown special case for old Hyper-V hosts
hv_sock: Remove check for old Hyper-V hosts
Drivers: hv: Remove support for WS2012/2012R2 & Win8/8.1 version of Hyper-V
hv_netvsc: Allocate send/receive buffers using vmbus_alloc_buffer()
Drivers: hv: vmbus: Add vmbus_alloc_buffer()/vmbus_free_buffer() for CoCo VMs
Drivers: hv: vmbus: add vmbus_establish_gpadl_caller_decrypted()
Drivers: hv: vmbus: Skip VMBus module cleanup for non-nested root partition
x86/hyperv: reserve more vectors
PCI: hv: Set irq_retrigger callback for the Hyper-V PCI MSI irqchip
Drivers: hv: Use meaningful errnos for hypercall status codes
In Hyper-V versions prior to WS2016/Win10, Hyper-V synthetic timers
interrupt the guest by delivering a message that is initially handled
by the Linux VMBus driver. Starting with WS2016/Win10, Hyper-V can
deliver stimer interrupts directly to an assigned interrupt vector
without involving the VMBus driver. This is called "Direct Mode".
With the overall removal of Linux support for running on Hyper-V
hosts earlier than WS2016 and Windows 10, it's no longer necessary
to support the legacy message-based delivery. Remove that delivery
mechanism and always use Direct Mode. If for some reason, the
Hyper-V host does not enumerate Direct Mode, output an error
message but continue to run using the LAPIC timer instead of an
stimer.
With these changes, the VMBus driver no longer calls the stimer
interrupt service routine. This removal has a broader benefit in
unblocking the disentangling of VMBus code and stimer code, as
they should be independent of each other. The final disentangling
will come as a follow-on patch set.
Signed-off-by: Michael Kelley <[email protected]>
Signed-off-by: Wei Liu <[email protected]>
Pull VDSO updates from Thomas Gleixner:
- Consolidate the VDSO datastore further and provide support for
mlock_all() and prefaulting.
- Provide 32-bit legacy time related functionality only if
CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists,
but architecture code still exposes the legacy functionality even
disabled.
Clean this up by adding the missing guards and validating at build
time that the VDSO is legacy free if disabled.
- Consolidate the VDSO related config options in core and drivers,
which removes some non-sensical dependencies and quite an amount of
#ifdeffery.
- Clean up the PAGE_SIZE definition maze
* tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
random: vDSO: Drop custom PAGE_SIZE definitions
LoongArch: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
clocksource/drivers/timer-riscv: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
clocksource/drivers/arm_arch_timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
clocksource/drivers/mips-gic-timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
MIPS: csrc-r4k: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
vDSO: Make clockmode constants available without CONFIG_GENERIC_GETTIMEOFDAY
kbuild: Support generated asm-headers in subdirectories
vdso: Rename HAVE_GENERIC_VDSO to VDSO_DATASTORE
vdso: Drop HAVE_GENERIC_VDSO from architecture kconfig files
vdso: Automatically select HAVE_GENERIC_VDSO if necessary
MIPS: vdso: Stop using CONFIG_HAVE_GENERIC_VDSO
vdso: Remove the dependency on HAVE_GENERIC_VDSO from ARCH_HAS_VDSO_ARCH_DATA
futex: Remove dependency on HAVE_GENERIC_VDSO from FUTEX_ROBUST_UNLOCK
vdso/gettimeofday: Verify COMPAT_32BIT_TIME interactions
sparc: vdso: Respect COMPAT_32BIT_TIME
MIPS: VDSO: Respect COMPAT_32BIT_TIME
powerpc/vdso: Respect COMPAT_32BIT_TIME
ARM: VDSO: Respect COMPAT_32BIT_TIME
arm64: vdso32: Respect COMPAT_32BIT_TIME
...
Pull clocksource/event driver updates from Thomas Gleixner:
- Remove redundant dev_err() and dev_err_probe() invocations in various
drivers
- Handle SWAP_IO_SPACE correctly in the rtl-otto driver
- Make the Samsumg PWM timer driver PREEMPT_RT compatible
- Ensure that the SUN4I timer is programmed with a delta larger than
zero as a zero delta causes the the timer to be disabled
- The usual fixes and improvements all over the place
* tag 'timers-clocksource-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource/drivers/armada: Unwind timer clock on init failure
clocksource/drivers/rtl-otto: Change driver to use __raw reads and writes
clocksource/drivers/samsung_pwm: Switch to raw_spinlock_t type
clocksource/drivers/clps711x: Do not unmap clocksource MMIO
clocksource/drivers/nxp-pit: Fix IRQ leak on cpuhp_setup_state error path
clocksource/drivers/timer-sun4i: Advertise a real minimum delta
clocksource: Remove redundant dev_err()/dev_err_probe()
clocksource/drivers/sh_cmt: Use named initializers for platform_device_id arrays
clocksource/drivers/sh_mtu2: Drop unused assignment of platform_device_id
The Armada timer init paths enable their clock before calling the
common initialization routine. If that routine returns an error, the
clock is left enabled even though the timer was not initialized
successfully.
Fixes: 12549e27c6 ("clocksource/drivers/time-armada-370-xp: Convert init function to return error")
Signed-off-by: Yuho Choi <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
As it stands, the driver uses ioread32 and iowrite32 for register
access and it works fine. However this stops working when the
SWAP_IO_SPACE config is enabled as this drivers expects ioread32 and
iowrite32 to be in native endian (that is big endian for currently
supported SoCs). RTL9607C is a big endian MIPS SoC that has identical
timer as the already supported chips but needs to have SWAP_IO_SPACE
to have a functioning little endian USB host.
Fix this by replacing all instances of ioread32 and iowrite32 with
__raw_readl and __raw_writel variants. Since they essentially do the
same register access, this shouldn't affect anything on other
machines.
Signed-off-by: Rustam Adilov <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Chris Packham <[email protected]>
Link: https://patch.msgid.link/[email protected]
Samsung PWM timer might be used as a clock source on some legacy systems.
When PREEMPT_RT is enabled on ARM, regular spinlock is converted to a
sleeping lock (mutex-based), which must not be used in atomic context
such as hard interrupt handlers. Switch the samsung_pwm_lock to the
raw_spinlock, which remains a true non-sleeping spinlock even
under PREEMPT_RT.
Fixes: 7aac482e62 ("clocksource: samsung_pwm_timer: Make PWM spinlock global")
Fixes: f11899894c ("clocksource: add samsung pwm timer driver")
Signed-off-by: Marek Szyprowski <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Sebastian Andrzej Siewior <[email protected]>
Acked-by: Uwe Kleine-König <[email protected]>
Link: https://patch.msgid.link/[email protected]
clps711x_clksrc_init() stores the timer base address in the static tcd
pointer and registers it as both the clocksource MMIO address and the
sched_clock read address.
The clocksource init path must therefore keep the mapping alive after
clps711x_timer_init() returns. However, the shared unmap_io exit path is
also reached after successful clocksource registration, so the MMIO
mapping is torn down while the clocksource and sched_clock readers may
still access it.
Return directly after successful clocksource registration and leave the
mapping alive for the registered readers. Keep the unmap_io path for the
error paths and for the clockevent init path.
Fixes: cd32e596f0 ("clocksource/drivers/clps711x: Fix resource leaks in error paths")
Signed-off-by: Guangshuo Li <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
When cpuhp_setup_state fails after pit_clockevent_per_cpu_init has
successfully called request_irq, the error handling jumps directly to
out_pit_clocksource_unregister without freeing the registered IRQ.
This leaks the IRQ line and, since kfree(pit) follows, leaves a
dangling pointer registered as the interrupt handler's dev_id,
potentially leading to a use-after-free if the IRQ fires afterwards.
Fix it by calling pit_clockevent_per_cpu_exit to properly release the
IRQ before falling through to the existing cleanup chain.
Suggested-by: Greg KH <[email protected]>
Fixes: bee33f22d7 ("clocksource/drivers/nxp-pit: Add NXP Automotive s32g2 / s32g3 support")
Cc: [email protected]
Signed-off-by: WenTao Liang <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
It appears that the bcm2712 SoC found in the relatively popular RPi5 has a
broken EL2 virtual timer.
Tthe reason why the timer isn't working is unknown (the timer is ticking,
but the interrupt never fires), and the SoC vendor doesn't communicate on
the reason why this isn't working, leaving users and maintainers in the
dark.
Paper over the issue by detecting the broken HW, falling back to the
physical timer instead, and let the user know about it. Also taint the
kernel as the machine is definitely not compliant with the spec, and it's
unknown what else is wrong with it.
Reported-by: John <[email protected]>
Reported-by: Daniel Drake <[email protected]>
Reported-by: Marek Szyprowski <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Gary Guo <[email protected]>
Acked-by: Florian Fainelli <[email protected]>
Cc: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
Pull vdso updates from Thomas Gleixner:
- Remove the redundant CONFIG_GENERIC_TIME_VSYSCALL after converting
the remaining users over.
- Rework and sanitize the MIPS VDSO handling, so it does not handle the
time related VDSO if there is no VDSO capable clocksource available.
Also stop mapping VDSO data pages unconditionally even if there is no
usage possible.
* tag 'timers-vdso-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip:
MIPS: VDSO: Fold MIPS_CLOCK_VSYSCALL into MIPS_GENERIC_GETTIMEOFDAY
MIPS: VDSO: Gate microMIPS restriction on GCC version
MIPS: VDSO: Fold MIPS_DISABLE_VDSO into MIPS_GENERIC_GETTIMEOFDAY
clocksource/drivers/mips-gic-timer: Only use VDSO_CLOCKMODE_GIC when it is a available
MIPS: csrc-r4k: Only use VDSO_CLOCKMODE_R4K when it is a available
MIPS: VDSO: Only map the data pages when the vDSO is used
MIPS: Introduce Kconfig MIPS_GENERIC_GETTIMEOFDAY
vdso/datastore: Always provide symbol declarations
MAINTAINERS: Add include/linux/vdso_datastore.h to vDSO block
vdso/gettimeofday: Rename __arch_get_vdso_u_timens_data()
vdso/treewide: Drop GENERIC_TIME_VSYSCALL
vdso/vsyscall: Gate update_vsyscall() behind CONFIG_GENERIC_GETTIMEOFDAY
riscv: vdso: Drop CONFIG_GENERIC_TIME_VSYSCALL guard around syscall fallbacks
Pull timekeeping updates from Thomas Gleixner:
"Updates for NTP/timekeeping and PTP:
- Expand timekeeping snapshot mechanisms
The various snapshot functions are mostly used for PTP to collect
"atomic" snapshots of various involved clocks.
They lack support for the recently introduced AUX clocks and do not
provide the underlying counter value (e.g. TSC) to user space.
Exposing the counter value snapshot allows for better control and
steering.
Convert the hard wired ktime_get_snapshot() to take a clock ID,
which allows the caller to select the clock ID to be captured along
with CLOCK_MONONOTONIC_RAW. Additionally capture the underlying
hardware counter value and the clock source ID of the counter.
Expand the hardware based snapshot capture where devices provide a
mechanism to snapshot the hardware PTP clock and the system counter
(usually via PCI/PTM) to support AUX clocks and also provide the
captured counter value back to the caller and not only the clock
timestamps derived from it.
- Add a new optional read_snapshot() callback to clocksources
That is required to capture atomic snapshots from clocksources
which are derived from TSC with a scaling mechanism (e.g. Hyper-V,
KVMclock).
The value pair is handed back in the snapshot structure to the
callers, so they can do the necessary correlations in a more
precise way.
This touches usage sites of the affected functions and data structure
all over the tree, but stays fully backwards compatible for the
existing user space exposed interfaces. New PTP IOCTLs will provide
access to the extended functionality in later kernel versions"
* tag 'timers-ptp-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: (28 commits)
ptp: vmclock: Use hw_cycles from snapshot for precise TSC pairing
x86/kvmclock: Implement read_snapshot() for kvmclock clocksource
clocksource/hyperv: Implement read_snapshot() for TSC page clocksource
timekeeping: Add clocksource read_snapshot() method and hw_cycles to snapshot
ptp: Switch to ktime_get_snapshot_id() for pre/post timestamps
timekeeping: Add support for AUX clock cross timestamping
timekeeping: Remove system_device_crosststamp::sys_realtime
ALSA: hda/common: Use system_device_crosststamp::sys_systime
wifi: iwlwifi: Use system_device_crosststamp::sys_systime
ptp: Use system_device_crosststamp::sys_systime
timekeeping: Prepare for cross timestamps on arbitrary clock IDs
timekeeping: Remove ktime_get_snapshot()
virtio_rtc: Use provided clock ID for history snapshot
net/mlx5: Use provided clock ID for history snapshot
igc: Use provided clock ID for history snapshot
ice/ptp: Use provided clock ID for history snapshot
wifi: iwlwifi: Adopt PTP cross timestamps to core changes
timekeeping: Add CLOCK ID to system_device_crosststamp
timekeeping: Add system_counterval_t to struct system_device_crosststamp
timekeeping: Add CLOCK_AUX support for ktime_get_snapshot_id()
...
The Kconfig logic for selecting the scheduler clocksource on
NXP Vybrid (VF610) uses a `choice` block restricted to 32-bit ARM. This
prevents 64-bit architectures, such as the NXP S32 family, from enabling
the NXP Periodic Interrupt Timer (PIT) driver (CONFIG_NXP_PIT_TIMER).
Relocate the NXP clocksource selection from arch/arm/mach-imx/Kconfig to
drivers/clocksource/Kconfig. This allows the configuration to be shared
across different architectures.
Update the selection to include support for ARCH_S32 and add a "None"
option restricted to ARCH_S32, since Vybrid lacks the ARM Architected
Timer. The Vybrid Global Timer option is restricted to ARCH_MULTI_V7
SOC_VF610 platforms to prevent it from being visible on Cortex-M4 builds,
which lack the ARM Global Timer hardware.
Fixes: bee33f22d7 ("clocksource/drivers/nxp-pit: Add NXP Automotive s32g2 / s32g3 support")
Signed-off-by: Enric Balletbo i Serra <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Link: https://patch.msgid.link/[email protected]
Tegra SoCs supports multiple watchdog timers. If the kernel crashes or
hangs before userspace enables a watchdog, the system cannot recover and
may remain bricked, e.g. after a failed OTA update. The driver currently
leaves all watchdogs disabled until userspace configures them.
Reserve first available watchdog as a kernel-only watchdog for Tegra186
and Tegra234. Arm it during probe (120s timeout) and keep it alive in
the driver IRQ handler. Do not register it to userspace. Other available
watchdogs remain exposed to userspace. This guarantees the system can
reset itself in case of a hang or crash even when userspace never starts.
Signed-off-by: Kartik Rajput <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Jon Hunter <[email protected]>
Link: https://patch.msgid.link/[email protected]
Tegra186+ SoCs expose multiple watchdog timers, but the driver only
registers WDT(0).
Iterate over num_wdts and, for each WDT, check the SCR (firewall) registers
in the TKE block to determine whether Linux has read and write access.
Register the watchdogs that are accessible.
Signed-off-by: Kartik Rajput <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Jon Hunter <[email protected]>
Link: https://patch.msgid.link/[email protected]
On Tegra186 and Tegra234, WDT2 is connected to the Audio Processing
Engine (APE) and cannot be accessed from Linux. Only WDT0 and WDT1
are accessible to Linux.
Update num_wdts from 3 to 2 for both Tegra186 and Tegra234 to reflect
the actual number of watchdogs available to Linux.
Signed-off-by: Kartik Rajput <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Jon Hunter <[email protected]>
Link: https://patch.msgid.link/[email protected]
Tegra SoCs support multiple watchdogs; currently only one (WDT0) is
used. When multiple watchdogs are registered, tegra186_wdt_enable()
overwrites the TKEIE(x) register, discarding any existing watchdog
interrupt enable bits. As a result, enabling one watchdog inadvertently
disables interrupts for the others.
Fix this by preserving the existing TKEIE(x) value and updating it
using a read-modify-write sequence.
Fixes: 42cee19a9f ("clocksource: Add Tegra186 timers support")
Cc: [email protected]
Signed-off-by: Kartik Rajput <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Jon Hunter <[email protected]>
Link: https://patch.msgid.link/[email protected]
VDSO_CLOCKMODE_GIC is only defined if CONFIG_GENERIC_GETTIMEOFDAY is
enabled. Right now this is always the case, but it will change soon.
Prepare for the potential unavailability of VDSO_CLOCKMODE_GIC.
Signed-off-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Link: https://patch.msgid.link/[email protected]
Implement the read_snapshot() callback for the Hyper-V TSC page clock-
source. This returns the derived 10MHz reference time (for timekeeping)
while also providing the raw TSC value that was used to compute it.
When the TSC page is valid, hv_read_tsc_page_tsc() atomically captures both
values from a single RDTSC inside the sequence-counter protected read. When
the TSC page is invalid (sequence == 0), the hw_csid and hw_cycles are set
to zero indicating no value is available.
This enables ktime_get_snapshot_id() to provide the raw TSC to consumers
like KVM's master clock when running nested guests under Hyper-V.
Signed-off-by: David Woodhouse <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Assisted-by: Kiro:claude-opus-4.6-1m
Reviewed-by: Michael Kelley <[email protected]>
Link: https://patch.msgid.link/[email protected]
Add support for using the TI Dual-Mode Timer for clockevents. The second
always on device with the "ti,timer-alwon" property is selected to be
used for clockevents. The first one is used as clocksource.
This allows clockevents to be setup independently of the CPU.
Signed-off-by: Markus Schneider-Pargmann (TI) <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
Add support for using the TI Dual-Mode Timer as a clocksource. The
driver automatically picks the first timer that is marked as always-on
on with the "ti,timer-alwon" property to be the clocksource.
The timer can then be used for CPU independent time keeping.
Signed-off-by: Markus Schneider-Pargmann (TI) <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
When running with at EL2 with VHE enabled, the architecture provides
two EL2 timer/counters, dubbed physical and virtual. Apart from their
names, they are strictly identical.
However, they don't get virtualised the same way, specially when
it comes to adding arbitrary offsets to the timers. When running as
a guest, the host CNTVOFF_EL2 does apply to the guest's view of
CNTHV*_El2. This is not true for CNTPOFF_EL2 and CNTHP*_EL2, as
the architecture is broken past the first level of virtualisation
(it lacks some essential mechanisms to be usable, despite what
the ARM ARM pretends).
This means that when running as a L2 guest hypervisor, using the
physical timer results in traps to L0, which are then forwarded to
L1 in order to emulate the offset, leading to even worse performance
due to massive trap amplification (the combination of register and
ERET trapping is absolutely lethal).
Switch the arch timer code to using the virtual timer when running
in VHE by default, only using the physical timer if the interrupt
is not correctly described in the firmware tables (which seems
to be an unfortunately common case). This comes as no impact on
bare-metal, and slightly improves the situation in the virtualised
case.
Signed-off-by: Marc Zyngier <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
# New commits in timers/clocksource:
68ed094971 ("clocksource/drivers/timer-of: Make the code compatible with modules")
2423405880 ("clocksource/drivers/mmio: Make the code compatible with modules")
fed9f727cc ("clocksource/drivers/sun5i: Handle error returns from devm_reset_control_get_optional_exclusive()")
045a9dac7e ("clocksource/drivers/timer-rtl-otto: Make rttm_cs variable static")
b385caf918 ("dt-bindings: timer: fsl,imxgpt: add compatible string fsl,imx25-epit")
Signed-off-by: Ingo Molnar <[email protected]>
The next changes will bring the module support on the timer
drivers. Those use the API exported by the timer-of which are not
exporting their symbols. Fix that by adding EXPORT_SYMBOL_GPL().
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
The next changes will bring the module support on the timer
drivers. Those use the API exported by the mmio clocksource which are
not exporting their symbols. Fix that by adding EXPORT_SYMBOL_GPL().
Signed-off-by: Daniel Lezcano <[email protected]>
Acked-by: John Stultz <[email protected]>
Link: https://patch.msgid.link/[email protected]
The devm_reset_control_get_optional_exclusive() function may return an
ERR_PTR in case of genuine reset control acquisition errors, not just
NULL which indicates the legitimate absence of an optional reset.
Add an IS_ERR() check after the call in sun5i_timer_probe(). On error,
return the error code to ensure proper failure handling rather than
proceeding with invalid pointers.
Fixes: 7e5bac610d ("clocksource/drivers/sun5i: Convert to platform device driver")
Signed-off-by: Chen Ni <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Acked-by: Chen-Yu Tsai <[email protected]>
Link: https://patch.msgid.link/[email protected]
File-scope 'rttm_cs' is not used outside of this unit, so make it static
to silence sparse warning:
timer-rtl-otto.c:228:16: warning: symbol 'rttm_cs' was not declared. Should it be static?
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
The clocksource watchdog code has over time reached the state of an
impenetrable maze of duct tape and staples. The original design, which was
made in the context of systems far smaller than today, is based on the
assumption that the to be monitored clocksource (TSC) can be trivially
compared against a known to be stable clocksource (HPET/ACPI-PM timer).
Over the years it turned out that this approach has major flaws:
- Long delays between watchdog invocations can result in wrap arounds
of the reference clocksource
- Scalability of the reference clocksource readout can degrade on large
multi-socket systems due to interconnect congestion
This was addressed with various heuristics which degraded the accuracy of
the watchdog to the point that it fails to detect actual TSC problems on
older hardware which exposes slow inter CPU drifts due to firmware
manipulating the TSC to hide SMI time.
To address this and bring back sanity to the watchdog, rewrite the code
completely with a different approach:
1) Restrict the validation against a reference clocksource to the boot
CPU, which is usually the CPU/Socket closest to the legacy block which
contains the reference source (HPET/ACPI-PM timer). Validate that the
reference readout is within a bound latency so that the actual
comparison against the TSC stays within 500ppm as long as the clocks
are stable.
2) Compare the TSCs of the other CPUs in a round robin fashion against
the boot CPU in the same way the TSC synchronization on CPU hotplug
works. This still can suffer from delayed reaction of the remote CPU
to the SMP function call and the latency of the control variable cache
line. But this latency is not affecting correctness. It only affects
the accuracy. With low contention the readout latency is in the low
nanoseconds range, which detects even slight skews between CPUs. Under
high contention this becomes obviously less accurate, but still
detects slow skews reliably as it solely relies on subsequent readouts
being monotonically increasing. It just can take slightly longer to
detect the issue.
3) Rewrite the watchdog test so it tests the various mechanisms one by
one and validating the result against the expectation.
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Borislav Petkov (AMD) <[email protected]>
Tested-by: Daniel J Blueman <[email protected]>
Reviewed-by: Jiri Wiesner <[email protected]>
Reviewed-by: Daniel J Blueman <[email protected]>
Link: https://patch.msgid.link/[email protected]
Link: https://patch.msgid.link/87h5qeomm5.ffs@tglx
MIPS selects CLOCKSOURCE_WATCHDOG, but none of the clocksources actually
sets the MUST_VERIFY flag. So compiling the watchdog in is a pointless
exercise. Remove the selects.
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://patch.msgid.link/[email protected]
This converts some of the visually simpler cases that have been split
over multiple lines. I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.
Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script. I probably had made it a bit _too_ trivial.
So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.
The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.
Signed-off-by: Linus Torvalds <[email protected]>
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.
As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.
Signed-off-by: Linus Torvalds <[email protected]>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <[email protected]>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <[email protected]>
Pull x86 paravirt updates from Borislav Petkov:
- A nice cleanup to the paravirt code containing a unification of the
paravirt clock interface, taming the include hell by splitting the
pv_ops structure and removing of a bunch of obsolete code (Juergen
Gross)
* tag 'x86_paravirt_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
x86/paravirt: Use XOR r32,r32 to clear register in pv_vcpu_is_preempted()
x86/paravirt: Remove trailing semicolons from alternative asm templates
x86/pvlocks: Move paravirt spinlock functions into own header
x86/paravirt: Specify pv_ops array in paravirt macros
x86/paravirt: Allow pv-calls outside paravirt.h
objtool: Allow multiple pv_ops arrays
x86/xen: Drop xen_mmu_ops
x86/xen: Drop xen_cpu_ops
x86/xen: Drop xen_irq_ops
x86/paravirt: Move pv_native_*() prototypes to paravirt.c
x86/paravirt: Introduce new paravirt-base.h header
x86/paravirt: Move paravirt_sched_clock() related code into tsc.c
x86/paravirt: Use common code for paravirt_steal_clock()
riscv/paravirt: Use common code for paravirt_steal_clock()
loongarch/paravirt: Use common code for paravirt_steal_clock()
arm64/paravirt: Use common code for paravirt_steal_clock()
arm/paravirt: Use common code for paravirt_steal_clock()
sched: Move clock related paravirt code to kernel/sched
paravirt: Remove asm/paravirt_api_clock.h
x86/paravirt: Move thunk macros to paravirt_types.h
...
Pull clocksource updates from Thomas Gleixner:
"A rather small set of boring cleanups, fixes and improvements"
* tag 'timers-clocksource-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource/drivers/mips-gic-timer: Move GIC timer to request_percpu_irq()
clocksource/drivers/timer-sp804: Fix an Oops when read_current_timer is called on ARM32 platforms where the SP804 is not registered as the sched_clock.
clocksource/drivers/armada-370-xp: Fix dead link to timer binding
clocksource/drivers/timer-integrator-ap: Add missing Kconfig dependency on OF
clocksource/drivers/sh_tmu: Always leave device running after probe
Pull irq core updates from Thomas Gleixner:
"Updates for the interrupt core subsystem:
- Remove the interrupt timing infrastructure
This was added seven years ago to be used for power management
purposes, but that integration never happened.
- Clean up the remaining setup_percpu_irq() users
The memory allocator is available when interrupts can be requested
so there is not need for static irq_action. Move the remaining
users to request_percpu_irq() and delete the historical cruft.
- Warn when interrupt flag inconsistencies are detected in
request*_irq().
Inconsistent flags can lead to hard to diagnose malfunction. The
fallout of this new warning has been addressed in next and the
fixes are coming in via the maintainer trees and the tip
irq/cleanup pull requests.
- Invoke affinity notifier when CPU hotplug breaks affinity
Otherwise the code using the notifier misses the affinity change
and operates on stale information.
- The usual cleanups and improvements"
* tag 'irq-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/proc: Replace snprintf with strscpy in register_handler_proc
genirq/cpuhotplug: Notify about affinity changes breaking the affinity mask
genirq: Move clear of kstat_irqs to free_desc()
genirq: Warn about using IRQF_ONESHOT without a threaded handler
irqdomain: Fix up const problem in irq_domain_set_name()
genirq: Remove setup_percpu_irq()
clocksource/drivers/mips-gic-timer: Move GIC timer to request_percpu_irq()
MIPS: Move IP27 timer to request_percpu_irq()
MIPS: Move IP30 timer to request_percpu_irq()
genirq: Remove __request_percpu_irq() helper
genirq: Remove IRQ timing tracking infrastructure
On SP804, the delay timer shares the same clkevt instance with
sched_clock. On some platforms, when
sp804_clocksource_and_sched_clock_init is called with use_sched_clock
not set to 1, sched_clkevt is not properly initialized. However,
sp804_register_delay_timer is invoked unconditionally, and
read_current_timer() subsequently calls sp804_read on an uninitialized
sched_clkevt, leading to a kernel Oops when accessing
sched_clkevt->value.
Declare a dedicated clkevt instance exclusively for delay timer,
instead of sharing the same clkevt with sched_clock. This ensures
that read_current_timer continues to work correctly regardless of
whether SP804 is selected as the sched_clock.
Fixes: 640594a04f ("clocksource/drivers/timer-sp804: Fix read_current_timer() issue when clock source is not registered")
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Stephen Eta Zhou <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
The old text binding 'marvell,armada-370-xp-timer.txt' was replaced by a
DT schema in commit '4334d83904fc'
("dt-bindings: timer: Convert marvell,armada-370-timer to DT schema").
Signed-off-by: Soham Metha <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Link: https://patch.msgid.link/[email protected]
Linus Torvalds