diff options
| author | James Hilliard <james.hilliard1@gmail.com> | 2026-10-26 12:11:31 -0600 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-10-30 16:15:58 -0700 |
| commit | 63787dfd1b5ae720cc30dab5e66c8e4d81ff7391 (patch) | |
| tree | 0c56baa092fc6626518856bc318f214be84bba68 | |
| parent | d3fcce5afe3bb62e8f7a2efb29e43da4fe4ae1f3 (diff) | |
ptp: vclock: preserve missing hardware timestamps
Socket timestamp delivery converts hardware timestamps to a bound
virtual clock before checking whether a hardware timestamp is present.
A zero timestamp means that the packet has no hardware timestamp, but
timecounter_cyc2time() can turn that zero into a nonzero virtual time.
The socket then reports a hardware timestamp which was never supplied.
Return zero without conversion when the input timestamp is absent.
This also covers skb_get_tx_timestamp(), which checks for an absent
timestamp after the same conversion.
This was identified during review of virtual clock sampling changes.
Fixes: d7c088265588 ("net: socket: support hardware timestamp conversion to PHC bound")
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Link: https://patch.msgid.link/20261026-ptp-vclock-sampling-v6-5-e705612541f1@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/ptp/ptp_vclock.c | 2 | ||||
| -rw-r--r-- | include/linux/ptp_clock_kernel.h | 2 |
2 files changed, 3 insertions, 1 deletions
diff --git a/drivers/ptp/ptp_vclock.c b/drivers/ptp/ptp_vclock.c index 679ae40916f7..e9cf4da3ed8a 100644 --- a/drivers/ptp/ptp_vclock.c +++ b/drivers/ptp/ptp_vclock.c @@ -326,6 +326,8 @@ ktime_t ptp_convert_timestamp(const ktime_t *hwtstamp, int vclock_index) u64 ns; ns = ktime_to_ns(*hwtstamp); + if (!ns) + return 0; srcu_idx = srcu_read_lock(&vclock_srcu); diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h index 36a27a910595..56f6ab1855d3 100644 --- a/include/linux/ptp_clock_kernel.h +++ b/include/linux/ptp_clock_kernel.h @@ -496,7 +496,7 @@ int ptp_get_vclocks_index(int pclock_index, int **vclock_index); * @hwtstamp: timestamp * @vclock_index: phc index of ptp vclock. * - * Returns: converted timestamp, or 0 on error. + * Returns: converted timestamp, or 0 if @hwtstamp is zero or on error. */ ktime_t ptp_convert_timestamp(const ktime_t *hwtstamp, int vclock_index); #else |