From: Florian Kauer florian.kauer@linutronix.de
[ Upstream commit c1bca9ac0bcb355be11354c2e68bc7bf31f5ac5a ]
It is possible (verified on a running system) that frames are processed by igc_tx_launchtime with a txtime before the start of the cycle (baset_est).
However, the result of txtime - baset_est is written into a u32, leading to a wrap around to a positive number. The following launchtime > 0 check will only branch to executing launchtime = 0 if launchtime is already 0.
Fix it by using a s32 before checking launchtime > 0.
Fixes: db0b124f02ba ("igc: Enhance Qbv scheduling by using first flag bit") Signed-off-by: Florian Kauer florian.kauer@linutronix.de Reviewed-by: Kurt Kanzenbach kurt@linutronix.de Tested-by: Naama Meir naamax.meir@linux.intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/igc/igc_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index 93e90c353f1a8..743d277896792 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -1014,7 +1014,7 @@ static __le32 igc_tx_launchtime(struct igc_ring *ring, ktime_t txtime, ktime_t base_time = adapter->base_time; ktime_t now = ktime_get_clocktai(); ktime_t baset_est, end_of_cycle; - u32 launchtime; + s32 launchtime; s64 n;
n = div64_s64(ktime_sub_ns(now, base_time), cycle_time);