| Message ID | 20200715132301.99816-7-hdegoede@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | usb: typec: tcpm: Fix AB BA lock inversion between tcpm and alt-mode drivers | expand |
On 7/15/20 6:23 AM, Hans de Goede wrote: > The tcpm.c code for sending VDMs assumes that there will only be one VDM > in flight at the time. The "queue" used by tcpm_queue_vdm is only 1 entry > deep. > > This assumes that the higher layers (tcpm state-machine and alt-mode > drivers) ensure that queuing a new VDM before the old one has been > completely send (or it timed out) add a WARN_ON to check for this. > > Signed-off-by: Hans de Goede <hdegoede@redhat.com> subject: s/tryong/trying/ > --- > drivers/usb/typec/tcpm/tcpm.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index ea14240423d1..5adc30666566 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -971,6 +971,9 @@ static void tcpm_queue_vdm_unlocked(struct tcpm_port *port, const u32 header, > { > WARN_ON(!mutex_is_locked(&port->lock)); > > + /* Make sure we are not still processing a previous VDM packet */ > + WARN_ON(port->vdm_state > VDM_STATE_DONE); > + > port->vdo_count = cnt + 1; > port->vdo_data[0] = header; > memcpy(&port->vdo_data[1], data, sizeof(u32) * cnt); >
Hi, On 7/15/20 6:06 PM, Guenter Roeck wrote: > On 7/15/20 6:23 AM, Hans de Goede wrote: >> The tcpm.c code for sending VDMs assumes that there will only be one VDM >> in flight at the time. The "queue" used by tcpm_queue_vdm is only 1 entry >> deep. >> >> This assumes that the higher layers (tcpm state-machine and alt-mode >> drivers) ensure that queuing a new VDM before the old one has been >> completely send (or it timed out) add a WARN_ON to check for this. >> >> Signed-off-by: Hans de Goede <hdegoede@redhat.com> > > subject: s/tryong/trying/ Ack, fixed for v2. Regards, Hans > >> --- >> drivers/usb/typec/tcpm/tcpm.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c >> index ea14240423d1..5adc30666566 100644 >> --- a/drivers/usb/typec/tcpm/tcpm.c >> +++ b/drivers/usb/typec/tcpm/tcpm.c >> @@ -971,6 +971,9 @@ static void tcpm_queue_vdm_unlocked(struct tcpm_port *port, const u32 header, >> { >> WARN_ON(!mutex_is_locked(&port->lock)); >> >> + /* Make sure we are not still processing a previous VDM packet */ >> + WARN_ON(port->vdm_state > VDM_STATE_DONE); >> + >> port->vdo_count = cnt + 1; >> port->vdo_data[0] = header; >> memcpy(&port->vdo_data[1], data, sizeof(u32) * cnt); >> >
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index ea14240423d1..5adc30666566 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -971,6 +971,9 @@ static void tcpm_queue_vdm_unlocked(struct tcpm_port *port, const u32 header, { WARN_ON(!mutex_is_locked(&port->lock)); + /* Make sure we are not still processing a previous VDM packet */ + WARN_ON(port->vdm_state > VDM_STATE_DONE); + port->vdo_count = cnt + 1; port->vdo_data[0] = header; memcpy(&port->vdo_data[1], data, sizeof(u32) * cnt);
The tcpm.c code for sending VDMs assumes that there will only be one VDM in flight at the time. The "queue" used by tcpm_queue_vdm is only 1 entry deep. This assumes that the higher layers (tcpm state-machine and alt-mode drivers) ensure that queuing a new VDM before the old one has been completely send (or it timed out) add a WARN_ON to check for this. Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- drivers/usb/typec/tcpm/tcpm.c | 3 +++ 1 file changed, 3 insertions(+)