On Mon, Jan 26, 2026 at 02:15:32PM +0800, Junjie Cao wrote: > Some PTP hardware clock (PHC) devices may return -EOPNOTSUPP for > operations like settime, adjtime, or adjfreq. This commonly occurs > with timestamp-only PHC implementations that don't support full clock > control. > > For background, syzbot previously exposed a crash risk when PTP clock > drivers lacked required callbacks[1]. Subsequent work[2] made callback > presence a registration requirement. As a result, some drivers (like > iwlwifi MVM/MLD[3]) now provide stub callbacks that return -EOPNOTSUPP > for unsupported operations. > > When phc_ctl encounters such devices, the "Operation not supported" > error should be treated as a skip (device limitation) rather than a > test failure. This patch: > - Adds [SKIP] output handling in log_test() > - Detects "Operation not supported" from phc_ctl and returns ksft_skip > - Returns ksft_skip if all tests are skipped, preventing false-positive > results when testing timestamp-only PHC implementations > > Link: > https://lore.kernel.org/netdev/[email protected]/ > [1] > Link: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dfb073d32cac > [2] > Link: https://lore.kernel.org/netdev/[email protected]/ > [3] > Signed-off-by: Junjie Cao <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
