4.14-stable review patch. If anyone has any objections, please let me know.
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From: Jacob Keller jacob.e.keller@intel.com
[ Upstream commit c79756cb5f084736b138da9319a02f7c72644548 ]
In commit bbc4e7d273b5 ("i40e: fix race condition with PTP_TX_IN_PROGRESS bits") we modified the code which handles Tx timestamps so that we would clear the progress bit as soon as possible.
A later commit 0bc0706b46cd ("i40e: check for Tx timestamp timeouts during watchdog") introduced similar code for detecting and handling cleanup of a blocked Tx timestamp. This code did not use the same pattern for cleaning up the skb.
Update this code to wait to free the skb until after the bit lock is free, by first setting the ptp_tx_skb to NULL and clearing the lock.
Signed-off-by: Jacob Keller jacob.e.keller@intel.com Tested-by: Andrew Bowers andrewx.bowers@intel.com Signed-off-by: Jeff Kirsher jeffrey.t.kirsher@intel.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/intel/i40e/i40e_ptp.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/intel/i40e/i40e_ptp.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ptp.c @@ -337,6 +337,8 @@ void i40e_ptp_rx_hang(struct i40e_pf *pf **/ void i40e_ptp_tx_hang(struct i40e_pf *pf) { + struct sk_buff *skb; + if (!(pf->flags & I40E_FLAG_PTP) || !pf->ptp_tx) return;
@@ -349,9 +351,12 @@ void i40e_ptp_tx_hang(struct i40e_pf *pf * within a second it is reasonable to assume that we never will. */ if (time_is_before_jiffies(pf->ptp_tx_start + HZ)) { - dev_kfree_skb_any(pf->ptp_tx_skb); + skb = pf->ptp_tx_skb; pf->ptp_tx_skb = NULL; clear_bit_unlock(__I40E_PTP_TX_IN_PROGRESS, pf->state); + + /* Free the skb after we clear the bitlock */ + dev_kfree_skb_any(skb); pf->tx_hwtstamp_timeouts++; } }