From: Miroslav Lichvar mlichvar@redhat.com
[ Upstream commit bfcbb76b0f595ea9ede9f7a218086fef85242f10 ]
When unregistering a physical clock which has some virtual clocks, unregister the virtual clocks with it.
This fixes the following oops, which can be triggered by unloading a driver providing a PTP clock when it has enabled virtual clocks:
BUG: unable to handle page fault for address: ffffffffc04fc4d8 Oops: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:ptp_vclock_read+0x31/0xb0 Call Trace: timecounter_read+0xf/0x50 ptp_vclock_refresh+0x2c/0x50 ? ptp_clock_release+0x40/0x40 ptp_aux_kworker+0x17/0x30 kthread_worker_fn+0x9b/0x240 ? kthread_should_park+0x30/0x30 kthread+0xe2/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30
Fixes: 73f37068d540 ("ptp: support ptp physical/virtual clocks conversion") Signed-off-by: Miroslav Lichvar mlichvar@redhat.com Acked-by: Richard Cochran richardcochran@gmail.com Cc: Yangbo Lu yangbo.lu@nxp.com Cc: Yang Yingliang yangyingliang@huawei.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ptp/ptp_clock.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index 0e4bc8b9329d..b6f2cfd15dd2 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -317,11 +317,18 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, } EXPORT_SYMBOL(ptp_clock_register);
+static int unregister_vclock(struct device *dev, void *data) +{ + struct ptp_clock *ptp = dev_get_drvdata(dev); + + ptp_vclock_unregister(info_to_vclock(ptp->info)); + return 0; +} + int ptp_clock_unregister(struct ptp_clock *ptp) { if (ptp_vclock_in_use(ptp)) { - pr_err("ptp: virtual clock in use\n"); - return -EBUSY; + device_for_each_child(&ptp->dev, NULL, unregister_vclock); }
ptp->defunct = 1;