kernel/linux.git/drivers/clocksource, branch v6.1.124

x86/hyperv: Fix hv tsc page based sched_clock for hibernation

2025-01-09T12:29:56+00:00

commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream. read_hv_sched_clock_tsc() assumes that the Hyper-V clock counter is bigger than the variable hv_sched_clock_offset, which is cached during early boot, but depending on the timing this assumption may be false when a hibernated VM starts again (the clock counter starts from 0 again) and is resuming back (Note: hv_init_tsc_clocksource() is not called during hibernation/resume); consequently, read_hv_sched_clock_tsc() may return a negative integer (which is interpreted as a huge positive integer since the return type is u64) and new kernel messages are prefixed with huge timestamps before read_hv_sched_clock_tsc() grows big enough (which typically takes several seconds). Fix the issue by saving the Hyper-V clock counter just before the suspend, and using it to correct the hv_sched_clock_offset in resume. This makes hv tsc page based sched_clock continuous and ensures that post resume, it starts from where it left off during suspend. Override x86_platform.save_sched_clock_state and x86_platform.restore_sched_clock_state routines to correct this as soon as possible. Note: if Invariant TSC is available, the issue doesn't happen because 1) we don't register read_hv_sched_clock_tsc() for sched clock: See commit e5313f1c5404 ("clocksource/drivers/hyper-v: Rework clocksource and sched clock setup"); 2) the common x86 code adjusts TSC similarly: see __restore_processor_state() -> tsc_verify_tsc_adjust(true) and x86_platform.restore_sched_clock_state(). Cc: stable@vger.kernel.org Fixes: 1349401ff1aa ("clocksource/drivers/hyper-v: Suspend/resume Hyper-V clocksource for hibernation") Co-developed-by: Dexuan Cui Signed-off-by: Dexuan Cui Signed-off-by: Naman Jain Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20240917053917.76787-1-namjain@linux.microsoft.com Signed-off-by: Wei Liu Message-ID: <20240917053917.76787-1-namjain@linux.microsoft.com> Signed-off-by: Naman Jain Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/timer-ti-dm: Fix child node refcount handling

2024-12-14T18:53:19+00:00

[ Upstream commit e5cfc0989d9a2849c51c720a16b90b2c061a1aeb ] of_find_compatible_node() increments the node's refcount, and it must be decremented again with a call to of_node_put() when the pointer is no longer required to avoid leaking the resource. Instead of adding the missing calls to of_node_put() in all execution paths, use the cleanup attribute for 'arm_timer' by means of the __free() macro, which automatically calls of_node_put() when the variable goes out of scope. Fixes: 25de4ce5ed02 ("clocksource/drivers/timer-ti-dm: Handle dra7 timer wrap errata i940") Signed-off-by: Javier Carrasco Link: https://lore.kernel.org/r/20241031-timer-ti-dm-systimer-of_node_put-v3-1-063ee822b73a@gmail.com Signed-off-by: Daniel Lezcano Signed-off-by: Sasha Levin

clocksource/drivers:sp804: Make user selectable

2024-12-14T18:53:19+00:00

[ Upstream commit 0309f714a0908e947af1c902cf6a330cb593e75e ] The sp804 is currently only user selectable if COMPILE_TEST, this was done by commit dfc82faad725 ("clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804") in order to avoid it being spuriously offered on platforms that won't have the hardware since it's generally only seen on Arm based platforms. This config is overly restrictive, while platforms that rely on the SP804 do select it in their Kconfig there are others such as the Arm fast models which have a SP804 available but currently unused by Linux. Relax the dependency to allow it to be user selectable on arm and arm64 to avoid surprises and in case someone comes up with a use for extra timer hardware. Fixes: dfc82faad725 ("clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804") Reported-by: Ross Burton Reviewed-by: Sudeep Holla Acked-by: Mark Rutland Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20241001-arm64-vexpress-sp804-v3-1-0a2d3f7883e4@kernel.org Signed-off-by: Daniel Lezcano Signed-off-by: Sasha Levin

clocksource/drivers/qcom: Add missing iounmap() on errors in msm_dt_timer_init()

2024-10-17T13:20:47+00:00

[ Upstream commit ca140a0dc0a18acd4653b56db211fec9b2339986 ] Add the missing iounmap() when clock frequency fails to get read by the of_property_read_u32() call, or if the call to msm_timer_init() fails. Fixes: 6e3321631ac2 ("ARM: msm: Add DT support to msm_timer") Signed-off-by: Ankit Agrawal Reviewed-by: Konrad Dybcio Link: https://lore.kernel.org/r/20240713095713.GA430091@bnew-VirtualBox Signed-off-by: Daniel Lezcano Signed-off-by: Sasha Levin

clocksource/drivers/timer-of: Remove percpu irq related code

2024-09-12T09:10:27+00:00

commit 471ef0b5a8aaca4296108e756b970acfc499ede4 upstream. GCC's named address space checks errors out with: drivers/clocksource/timer-of.c: In function ‘timer_of_irq_exit’: drivers/clocksource/timer-of.c:29:46: error: passing argument 2 of ‘free_percpu_irq’ from pointer to non-enclosed address space 29 | free_percpu_irq(of_irq->irq, clkevt); | ^~~~~~ In file included from drivers/clocksource/timer-of.c:8: ./include/linux/interrupt.h:201:43: note: expected ‘__seg_gs void *’ but argument is of type ‘struct clock_event_device *’ 201 | extern void free_percpu_irq(unsigned int, void __percpu *); | ^~~~~~~~~~~~~~~ drivers/clocksource/timer-of.c: In function ‘timer_of_irq_init’: drivers/clocksource/timer-of.c:74:51: error: passing argument 4 of ‘request_percpu_irq’ from pointer to non-enclosed address space 74 | np->full_name, clkevt) : | ^~~~~~ ./include/linux/interrupt.h:190:56: note: expected ‘__seg_gs void *’ but argument is of type ‘struct clock_event_device *’ 190 | const char *devname, void __percpu *percpu_dev_id) Sparse warns about: timer-of.c:29:46: warning: incorrect type in argument 2 (different address spaces) timer-of.c:29:46: expected void [noderef] __percpu * timer-of.c:29:46: got struct clock_event_device *clkevt timer-of.c:74:51: warning: incorrect type in argument 4 (different address spaces) timer-of.c:74:51: expected void [noderef] __percpu *percpu_dev_id timer-of.c:74:51: got struct clock_event_device *clkevt It appears the code is incorrect as reported by Uros Bizjak: "The referred code is questionable as it tries to reuse the clkevent pointer once as percpu pointer and once as generic pointer, which should be avoided." This change removes the percpu related code as no drivers is using it. [Daniel: Fixed the description] Fixes: dc11bae785295 ("clocksource/drivers: Add timer-of common init routine") Reported-by: Uros Bizjak Tested-by: Uros Bizjak Link: https://lore.kernel.org/r/20240819100335.2394751-1-daniel.lezcano@linaro.org Signed-off-by: Daniel Lezcano Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/imx-tpm: Fix next event not taking effect sometime

2024-09-12T09:10:27+00:00

commit 3d5c2f8e75a55cfb11a85086c71996af0354a1fb upstream. The value written into the TPM CnV can only be updated into the hardware when the counter increases. Additional writes to the CnV write buffer are ignored until the register has been updated. Therefore, we need to check if the CnV has been updated before continuing. This may require waiting for 1 counter cycle in the worst case. Cc: stable@vger.kernel.org Fixes: 059ab7b82eec ("clocksource/drivers/imx-tpm: Add imx tpm timer support") Signed-off-by: Jacky Bai Reviewed-by: Peng Fan Reviewed-by: Ye Li Reviewed-by: Jason Liu Signed-off-by: Frank Li Link: https://lore.kernel.org/r/20240725193355.1436005-2-Frank.Li@nxp.com Signed-off-by: Daniel Lezcano Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/imx-tpm: Fix return -ETIME when delta exceeds INT_MAX

2024-09-12T09:10:27+00:00

commit 5b8843fcd49827813da80c0f590a17ae4ce93c5d upstream. In tpm_set_next_event(delta), return -ETIME by wrong cast to int when delta is larger than INT_MAX. For example: tpm_set_next_event(delta = 0xffff_fffe) { ... next = tpm_read_counter(); // assume next is 0x10 next += delta; // next will 0xffff_fffe + 0x10 = 0x1_0000_000e now = tpm_read_counter(); // now is 0x10 ... return (int)(next - now) <= 0 ? -ETIME : 0; ^^^^^^^^^^ 0x1_0000_000e - 0x10 = 0xffff_fffe, which is -2 when cast to int. So return -ETIME. } To fix this, introduce a 'prev' variable and check if 'now - prev' is larger than delta. Cc: stable@vger.kernel.org Fixes: 059ab7b82eec ("clocksource/drivers/imx-tpm: Add imx tpm timer support") Signed-off-by: Jacky Bai Reviewed-by: Peng Fan Reviewed-by: Ye Li Reviewed-by: Jason Liu Signed-off-by: Frank Li Link: https://lore.kernel.org/r/20240725193355.1436005-1-Frank.Li@nxp.com Signed-off-by: Daniel Lezcano Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/arm_global_timer: Guard against division by zero

2024-08-29T15:30:36+00:00

[ Upstream commit e651f2fae33634175fae956d896277cf916f5d09 ] The result of the division of new_rate by gt_target_rate can be zero (if new_rate is smaller than gt_target_rate). Using that result as divisor without checking can result in a division by zero error. Guard against this by checking for a zero value earlier. While here, also change the psv variable to an unsigned long to make sure we don't overflow the datatype as all other types involved are also unsiged long. Signed-off-by: Martin Blumenstingl Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20240225151336.2728533-3-martin.blumenstingl@googlemail.com Signed-off-by: Sasha Levin

clocksource/drivers/sh_cmt: Address race condition for clock events

2024-08-14T11:52:45+00:00

[ Upstream commit db19d3aa77612983a02bd223b3f273f896b243cf ] There is a race condition in the CMT interrupt handler. In the interrupt handler the driver sets a driver private flag, FLAG_IRQCONTEXT. This flag is used to indicate any call to set_next_event() should not be directly propagated to the device, but instead cached. This is done as the interrupt handler itself reprograms the device when needed before it completes and this avoids this operation to take place twice. It is unclear why this design was chosen, my suspicion is to allow the struct clock_event_device.event_handler callback, which is called while the FLAG_IRQCONTEXT is set, can update the next event without having to write to the device twice. Unfortunately there is a race between when the FLAG_IRQCONTEXT flag is set and later cleared where the interrupt handler have already started to write the next event to the device. If set_next_event() is called in this window the value is only cached in the driver but not written. This leads to the board to misbehave, or worse lockup and produce a splat. rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=f5e0/0/0x0 softirq=519/519 fqs=0 (false positive?) rcu: (detected by 1, t=6502 jiffies, g=-595, q=77 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0-rc5-arm64-renesas-00019-g74a6f86eaf1c-dirty #20 Hardware name: Renesas Salvator-X 2nd version board based on r8a77965 (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : tick_check_broadcast_expired+0xc/0x40 lr : cpu_idle_poll.isra.0+0x8c/0x168 sp : ffff800081c63d70 x29: ffff800081c63d70 x28: 00000000580000c8 x27: 00000000bfee5610 x26: 0000000000000027 x25: 0000000000000000 x24: 0000000000000000 x23: ffff00007fbb9100 x22: ffff8000818f1008 x21: ffff8000800ef07c x20: ffff800081c79ec0 x19: ffff800081c70c28 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffffc2c717d8 x14: 0000000000000000 x13: ffff000009c18080 x12: ffff8000825f7fc0 x11: 0000000000000000 x10: ffff8000818f3cd4 x9 : 0000000000000028 x8 : ffff800081c79ec0 x7 : ffff800081c73000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : ffff7ffffe286000 x3 : 0000000000000000 x2 : ffff7ffffe286000 x1 : ffff800082972900 x0 : ffff8000818f1008 Call trace: tick_check_broadcast_expired+0xc/0x40 do_idle+0x9c/0x280 cpu_startup_entry+0x34/0x40 kernel_init+0x0/0x11c do_one_initcall+0x0/0x260 __primary_switched+0x80/0x88 rcu: rcu_preempt kthread timer wakeup didn't happen for 6501 jiffies! g-595 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=262 rcu: rcu_preempt kthread starved for 6502 jiffies! g-595 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:I stack:0 pid:15 tgid:15 ppid:2 flags:0x00000008 Call trace: __switch_to+0xbc/0x100 __schedule+0x358/0xbe0 schedule+0x48/0x148 schedule_timeout+0xc4/0x138 rcu_gp_fqs_loop+0x12c/0x764 rcu_gp_kthread+0x208/0x298 kthread+0x10c/0x110 ret_from_fork+0x10/0x20 The design have been part of the driver since it was first merged in early 2009. It becomes increasingly harder to trigger the issue the older kernel version one tries. It only takes a few boots on v6.10-rc5, while hundreds of boots are needed to trigger it on v5.10. Close the race condition by using the CMT channel lock for the two competing sections. The channel lock was added to the driver after its initial design. Signed-off-by: Niklas Söderlund Link: https://lore.kernel.org/r/20240702190230.3825292-1-niklas.soderlund+renesas@ragnatech.se Signed-off-by: Daniel Lezcano Signed-off-by: Sasha Levin

clocksource/drivers/arm_global_timer: Fix maximum prescaler value

2024-04-03T13:19:44+00:00

[ Upstream commit b34b9547cee41575a4fddf390f615570759dc999 ] The prescaler in the "Global Timer Control Register bit assignments" is documented to use bits [15:8], which means that the maximum prescaler register value is 0xff. Fixes: 171b45a4a70e ("clocksource/drivers/arm_global_timer: Implement rate compensation whenever source clock changes") Signed-off-by: Martin Blumenstingl Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20240218174138.1942418-2-martin.blumenstingl@googlemail.com Signed-off-by: Sasha Levin