ice: Don't process extts if PTP is disabled

The ice_ptp_extts_event() function can race with ice_ptp_release() and
result in a NULL pointer dereference which leads to a kernel panic.

Panic occurs because the ice_ptp_extts_event() function calls
ptp_clock_event() with a NULL pointer. The ice driver has already
released the PTP clock by the time the interrupt for the next external
timestamp event occurs.

To fix this, modify the ice_ptp_extts_event() function to check the
PTP state and bail early if PTP is not ready.

Fixes: 172db5f91d5f ("ice: add support for auxiliary input/output pins")
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://patch.msgid.link/20240702171459.2606611-3-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c
index 4d6555fadd83a130f2a5425dd8f97e4f747e63c3..9fef240bf68ddb8b022aa2c7cfdea3e5e68eb125 100644 (file)
--- a/drivers/net/ethernet/intel/ice/ice_ptp.c
+++ b/drivers/net/ethernet/intel/ice/ice_ptp.c
@@ -1559,6 +1559,10 @@ void ice_ptp_extts_event(struct ice_pf *pf)
        u8 chan, tmr_idx;
        u32 hi, lo;
 
+       /* Don't process timestamp events if PTP is not ready */
+       if (pf->ptp.state != ICE_PTP_READY)
+               return;
+
        tmr_idx = hw->func_caps.ts_func_info.tmr_index_owned;
        /* Event time is captured by one of the two matched registers
         *      GLTSYN_EVNT_L: 32 LSB of sampled time event