| Message ID | 20191218141656.12416-1-baijiaju1990@gmail.com |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | David Miller |
| Headers | show |
| Series | net: intel: e1000e: fix possible sleep-in-atomic-context bugs in e1000e_get_hw_semaphore() | expand |
> From: netdev-owner@vger.kernel.org <netdev-owner@vger.kernel.org> > On Behalf Of Jia-Ju Bai > Sent: Wednesday, December 18, 2019 6:17 AM > To: Kirsher, Jeffrey T <jeffrey.t.kirsher@intel.com>; davem@davemloft.net > Cc: intel-wired-lan@lists.osuosl.org; netdev@vger.kernel.org; linux- > kernel@vger.kernel.org; Jia-Ju Bai <baijiaju1990@gmail.com> > 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 <baijiaju1990@gmail.com> > --- > drivers/net/ethernet/intel/e1000e/mac.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > Tested-by: Aaron Brown <aaron.f.brown@intel.com>
diff --git a/drivers/net/ethernet/intel/e1000e/mac.c b/drivers/net/ethernet/intel/e1000e/mac.c index e531976f8a67..51512a73fdd0 100644 --- a/drivers/net/ethernet/intel/e1000e/mac.c +++ b/drivers/net/ethernet/intel/e1000e/mac.c @@ -1363,7 +1363,7 @@ s32 e1000e_get_hw_semaphore(struct e1000_hw *hw) if (!(swsm & E1000_SWSM_SMBI)) break; - usleep_range(50, 100); + udelay(100); i++; } @@ -1381,7 +1381,7 @@ s32 e1000e_get_hw_semaphore(struct e1000_hw *hw) if (er32(SWSM) & E1000_SWSM_SWESMBI) break; - usleep_range(50, 100); + udelay(100); } if (i == timeout) {
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 <baijiaju1990@gmail.com> --- drivers/net/ethernet/intel/e1000e/mac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)