> From: [email protected] <[email protected]>
> On Behalf Of Jia-Ju Bai
> Sent: Wednesday, December 18, 2019 6:17 AM
> To: Kirsher, Jeffrey T <[email protected]>; [email protected]
> Cc: [email protected]; [email protected]; linux-
> [email protected]; Jia-Ju Bai <[email protected]>
> Subject: [PATCH] net: intel: e1000e: fix possible sleep-in-atomic-context bugs
> in e1000e_get_hw_semaphore()
>
> The driver may sleep while holding a spinlock.
> The function call path (from bottom to top) in Linux 4.19 is:
>
> drivers/net/ethernet/intel/e1000e/mac.c, 1366:
> usleep_range in e1000e_get_hw_semaphore
> drivers/net/ethernet/intel/e1000e/80003es2lan.c, 322:
> e1000e_get_hw_semaphore in
> e1000_release_swfw_sync_80003es2lan
> drivers/net/ethernet/intel/e1000e/80003es2lan.c, 197:
> e1000_release_swfw_sync_80003es2lan in
> e1000_release_phy_80003es2lan
> drivers/net/ethernet/intel/e1000e/netdev.c, 4883:
> (FUNC_PTR) e1000_release_phy_80003es2lan in
> e1000e_update_phy_stats
> drivers/net/ethernet/intel/e1000e/netdev.c, 4917:
> e1000e_update_phy_stats in e1000e_update_stats
> drivers/net/ethernet/intel/e1000e/netdev.c, 5945:
> e1000e_update_stats in e1000e_get_stats64
> drivers/net/ethernet/intel/e1000e/netdev.c, 5944:
> spin_lock in e1000e_get_stats64
>
> drivers/net/ethernet/intel/e1000e/mac.c, 1384:
> usleep_range in e1000e_get_hw_semaphore
> drivers/net/ethernet/intel/e1000e/80003es2lan.c, 322:
> e1000e_get_hw_semaphore in
> e1000_release_swfw_sync_80003es2lan
> drivers/net/ethernet/intel/e1000e/80003es2lan.c, 197:
> e1000_release_swfw_sync_80003es2lan in
> e1000_release_phy_80003es2lan
> drivers/net/ethernet/intel/e1000e/netdev.c, 4883:
> (FUNC_PTR) e1000_release_phy_80003es2lan in
> e1000e_update_phy_stats
> drivers/net/ethernet/intel/e1000e/netdev.c, 4917:
> e1000e_update_phy_stats in e1000e_update_stats
> drivers/net/ethernet/intel/e1000e/netdev.c, 5945:
> e1000e_update_stats in e1000e_get_stats64
> drivers/net/ethernet/intel/e1000e/netdev.c, 5944:
> spin_lock in e1000e_get_stats64
>
> (FUNC_PTR) means a function pointer is called.
>
> To fix these bugs, usleep_range() is replaced with udelay().
>
> These bugs are found by a static analysis tool STCheck written by myself.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>
> ---
> drivers/net/ethernet/intel/e1000e/mac.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
Tested-by: Aaron Brown <[email protected]>