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 <torvalds@linux-foundation.org>
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 <kees@kernel.org>
To output UTC would involve complex calculations about whether the time
elapsed since the reference time has crossed the end of the month when
a leap second takes effect. I've prototyped that, but it made me sad.
Much better to report TAI, which is what PHCs should do anyway.
And much much simpler.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Babis Chalios <bchalios@amazon.es>
Tested-by: Takahiro Itazuri <itazur@amazon.com>
Link: https://patch.msgid.link/20260130173704.12575-8-itazur@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As we finalised the spec, we spotted that vmgenid actually says that the
_HID is supposed to be hypervisor-specific. Although in the 13 years
since the original vmgenid doc was published, nobody seems to have cared
about using _HID to distinguish between implementations on different
hypervisors, and we only ever use the _CID.
For consistency, match the _CID of "VMCLOCK" too.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Babis Chalios <bchalios@amazon.es>
Tested-by: Takahiro Itazuri <itazur@amazon.com>
Link: https://patch.msgid.link/20260130173704.12575-6-itazur@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add device tree support to the ptp_vmclock driver, allowing it to probe
via device tree in addition to ACPI.
Handle optional interrupt for clock disruption notifications, mirroring
the ACPI notification behaviour.
Although the interrupt is marked as 'optional' in the DT bindings, if
the device *advertises* the VMCLOCK_FLAG_NOTIFICATION_ABSENT then it
*should* have an interrupt. The driver will refuse to initialize if not.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Babis Chalios <bchalios@amazon.es>
Signed-off-by: Takahiro Itazuri <itazur@amazon.com>
Tested-by: Takahiro Itazuri <itazur@amazon.com>
Link: https://patch.msgid.link/20260130173704.12575-5-itazur@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add optional support for device notifications in VMClock. When
supported, the hypervisor will send a device notification every time it
updates the seq_count to a new even value.
Moreover, add support for poll() in VMClock as a means to propagate this
notification to user space. poll() will return a POLLIN event to
listeners every time seq_count changes to a value different than the one
last seen (since open() or last read()/pread()). This means that when
poll() returns a POLLIN event, listeners need to use read() to observe
what has changed and update the reader's view of seq_count. In other
words, after a poll() returned, all subsequent calls to poll() will
immediately return with a POLLIN event until the listener calls read().
The device advertises support for the notification mechanism by setting
flag VMCLOCK_FLAG_NOTIFICATION_PRESENT in vmclock_abi flags field. If
the flag is not present the driver won't setup the ACPI notification
handler and poll() will always immediately return POLLHUP.
Signed-off-by: Babis Chalios <bchalios@amazon.es>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Takahiro Itazuri <itazur@amazon.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Tested-by: Takahiro Itazuri <itazur@amazon.com>
Link: https://patch.msgid.link/20260130173704.12575-3-itazur@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
vmclock_probe() uses an "out:" label to return from the function on
error. This indicates that some cleanup operation is necessary.
However the label does not do anything as all resources are managed
through devres, making the code slightly harder to read.
Remove the label and just return directly.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Most resources owned by the vmclock device are managed through devres.
Only the miscdev and ptp clock are managed manually.
This makes the code slightly harder to understand than necessary.
Switch them over to devres and remove the now unnecessary drvdata.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
vmclock_remove() tries to detect the successful registration of the misc
device based on the value of its minor value.
However that check is incorrect if the misc device registration was not
attempted in the first place.
Always initialize the minor number, so the check works properly.
Fixes: 2050327242 ("ptp: Add support for the AMZNC10C 'vmclock' device")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
If vmclock_ptp_register() fails during probing, vmclock_remove() is
called to clean up the ptp clock and misc device.
It uses dev_get_drvdata() to access the vmclock state.
However the driver data is not yet set at this point.
Assign the driver data earlier.
Fixes: 2050327242 ("ptp: Add support for the AMZNC10C 'vmclock' device")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The continual trickle of small conversion patches is grating on me, and
is really not helping. Just get rid of the 'remove_new' member
function, which is just an alias for the plain 'remove', and had a
comment to that effect:
/*
* .remove_new() is a relic from a prototype conversion of .remove().
* New drivers are supposed to implement .remove(). Once all drivers are
* converted to not use .remove_new any more, it will be dropped.
*/
This was just a tree-wide 'sed' script that replaced '.remove_new' with
'.remove', with some care taken to turn a subsequent tab into two tabs
to make things line up.
I did do some minimal manual whitespace adjustment for places that used
spaces to line things up.
Then I just removed the old (sic) .remove_new member function, and this
is the end result. No more unnecessary conversion noise.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The vmclock device addresses the problem of live migration with
precision clocks. The tolerances of a hardware counter (e.g. TSC) are
typically around ±50PPM. A guest will use NTP/PTP/PPS to discipline that
counter against an external source of 'real' time, and track the precise
frequency of the counter as it changes with environmental conditions.
When a guest is live migrated, anything it knows about the frequency of
the underlying counter becomes invalid. It may move from a host where
the counter running at -50PPM of its nominal frequency, to a host where
it runs at +50PPM. There will also be a step change in the value of the
counter, as the correctness of its absolute value at migration is
limited by the accuracy of the source and destination host's time
synchronization.
In its simplest form, the device merely advertises a 'disruption_marker'
which indicates that the guest should throw away any NTP synchronization
it thinks it has, and start again.
Because the shared memory region can be exposed all the way to userspace
through the /dev/vmclock0 node, applications can still use time from a
fast vDSO 'system call', and check the disruption marker to be sure that
their timestamp is indeed truthful.
The structure also allows for the precise time, as known by the host, to
be exposed directly to guests so that they don't have to wait for NTP to
resync from scratch. The PTP driver consumes this information if present.
Like the KVM PTP clock, this PTP driver can convert TSC-based cross
timestamps into KVM clock values. Unlike the KVM PTP clock, it does so
only when such is actually helpful.
The values and fields are based on the nascent virtio-rtc specification,
and the intent is that a version (hopefully precisely this version) of
this structure will be included as an optional part of that spec. In the
meantime, this driver supports the simple ACPI form of the device which
is being shipped in certain commercial hypervisors (and submitted for
inclusion in QEMU).
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
