ptp: Remove 'default y' for VMCLOCK PTP device

The VMCLOCK device gives support for accurate timekeeping even across
live migration, unlike the KVM PTP clock. To help ensure that users can
always use ptp_vmclock where it's available in preference to ptp_kvm,
set it to 'default PTP_1588_CLOCK_VMCLOCK' instead of 'default y'.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Link: https://patch.msgid.link/89955b74d225129d6e3d79b53aa8d81d1b50560f.camel@infradead.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
David Woodhouse 2024-11-02 16:52:17 -05:00 committed by Jakub Kicinski
parent 6a7d68f727
commit 18ec5491a4

View File

@ -135,12 +135,16 @@ config PTP_1588_CLOCK_VMCLOCK
tristate "Virtual machine PTP clock"
depends on X86_TSC || ARM_ARCH_TIMER
depends on PTP_1588_CLOCK && ACPI && ARCH_SUPPORTS_INT128
default y
default PTP_1588_CLOCK_KVM
help
This driver adds support for using a virtual precision clock
advertised by the hypervisor. This clock is only useful in virtual
machines where such a device is present.
Unlike the KVM virtual PTP clock, the VMCLOCK device offers support
for reliable timekeeping even across live migration. So this driver
is enabled by default whenever the KVM PTP clock is.
To compile this driver as a module, choose M here: the module
will be called ptp_vmclock.