[PATCH net v3 0/5] ptp: make virtual clock sampling and teardown failure-safe

[James Hilliard <james.hilliard1@gmail.com>]

Fix virtual-clock sampling errors, registration rollback and parent
teardown in separate patches. Keep failed PHC reads out of the timecounter
and serialize extended samples with virtual-clock adjustments. Also
preserve the zero sentinel for packets without hardware timestamps.

Unlike v2, this revision retains the existing cyclecounter mask, scaling
and conversion windows. It does not assume full-width nanosecond samples
or promise recovery of elapsed time after an unobserved counter wrap.

Changes in v3:
- Split the independent fixes into separate patches, as requested by Paolo.
- Retain the existing timecounter arithmetic and conversion windows; drop
  the full-width rewrite and extended-read anchor updates from v2.
- Propagate registration errors through sysfs, including a failed initial
  PHC sample, and initialize the counter before publishing the clock.
- Preserve absent hardware timestamps instead of converting zero.
- Correct the sysfs teardown rationale and its Fixes tag.
- Rebase onto current net.
- Link to v2: https://patch.msgid.link/20261005-ptp-vclock-sampling-v2-0-8ed12d4d10af@gmail.com

Changes in v2:
- Drain virtual clock sysfs changes before parent unregister walks children.
- Use full-width samples and overflow-safe scaling across long sampling gaps.
- Update the anchor for extended and cross-timestamp reads under the clock lock.
- Link to v1: https://patch.msgid.link/20260930-ptp-vclock-sampling-v1-1-c11bc16691ae@gmail.com

Assisted-by: Codex:gpt-6-astra
---
James Hilliard (5):
      ptp: drain virtual clock sysfs operations before unregistering children
      ptp: unwind partially completed virtual clock creation
      ptp: vclock: propagate physical clock sampling errors
      ptp: vclock: serialize extended samples with counter updates
      ptp: vclock: preserve missing hardware timestamps

 drivers/ptp/ptp_clock.c   |   5 +++
 drivers/ptp/ptp_private.h |   4 +-
 drivers/ptp/ptp_sysfs.c   |  18 ++++++++-
 drivers/ptp/ptp_vclock.c  | 100 +++++++++++++++++++++++++++++-----------------
 4 files changed, 87 insertions(+), 40 deletions(-)
---
base-commit: 513444cc62e231a11c9b15ea88de0890da9b2b4f
change-id: 20260930-ptp-vclock-sampling-902f98408c93

Best regards,
--  
James Hilliard <james.hilliard1@gmail.com>