linux.git/drivers/clocksource, branch v6.6.72

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

2025-01-10T13:31:36+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: Greg Kroah-Hartman

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

2025-01-10T13:31:36+00:00

This reverts commit 6681113633dc738ec95fe33104843a1e25acef3b which is
commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream.

The dependant patch before this one caused build errors in the 6.6.y
tree, so revert this for now so that we can fix them up properly.

Reported-by: Ignat Korchagin 
Link: https://lore.kernel.org/r/3DB3A6D3-0D3A-4682-B4FA-407B2D3263B2@cloudflare.com
Reported-by: Lars Wendler 
Link: https://lore.kernel.org/r/20250110103328.0e3906a8@chagall.paradoxon.rec
Reported-by: Chris Clayton 
Link: https://lore.kernel.org/r/10c7be00-b1f8-4389-801b-fb2d0b22468d@googlemail.com
Cc: Dexuan Cui 
Cc: Naman Jain 
Cc: Michael Kelley 
Cc: Wei Liu 
Cc: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

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

2025-01-09T12:31:49+00:00

[ Upstream commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 ]

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: Sasha Levin

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

2024-12-09T09:31:51+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

2024-12-09T09:31:51+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()

2024-10-04T14:29:04+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

2024-09-12T09:11:42+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

2024-09-12T09:11:41+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

2024-09-12T09:11:41+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

2024-08-29T15:33:35+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