[net 03/10] e1000e: fix locking issue with e1000e_disable_aspm
From: Jeff Kirsher <hidden>
Date: 2015-06-26 10:20:47
Subsystem:
intel ethernet drivers, networking drivers, the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Yanir Lubetkin <redacted> e1000e_disable_aspm called pci_disable_link_state_locked which requires pci_bus_sem to be held, but is also called from places where this semaphore was not previously acquired. This patch implements two flavors of disable_aspm, one that acquires the lock, and the other (_locked) which should be called when the semaphore is already acquired. Signed-off-by: Yanir Lubetkin <redacted> Tested-by: Aaron Brown <redacted> Signed-off-by: Jeff Kirsher <redacted> --- drivers/net/ethernet/intel/e1000e/netdev.c | 38 ++++++++++++++++++++++++++---- 1 file changed, 34 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index e62b9dc..89d788d 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c@@ -6354,13 +6354,14 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool runtime) } /** - * e1000e_disable_aspm - Disable ASPM states + * __e1000e_disable_aspm - Disable ASPM states * @pdev: pointer to PCI device struct * @state: bit-mask of ASPM states to disable + * @locked: indication if this context holds pci_bus_sem locked. * * Some devices *must* have certain ASPM states disabled per hardware errata. **/ -static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state) +static void __e1000e_disable_aspm(struct pci_dev *pdev, u16 state, int locked) { struct pci_dev *parent = pdev->bus->self; u16 aspm_dis_mask = 0;
@@ -6399,7 +6400,10 @@ static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state) "L1" : ""); #ifdef CONFIG_PCIEASPM - pci_disable_link_state_locked(pdev, state); + if (locked) + pci_disable_link_state_locked(pdev, state); + else + pci_disable_link_state(pdev, state); /* Double-check ASPM control. If not disabled by the above, the * BIOS is preventing that from happening (or CONFIG_PCIEASPM is
@@ -6422,6 +6426,32 @@ static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state) aspm_dis_mask); } +/** + * e1000e_disable_aspm - Disable ASPM states. + * @pdev: pointer to PCI device struct + * @state: bit-mask of ASPM states to disable + * + * This function acquires the pci_bus_sem! + * Some devices *must* have certain ASPM states disabled per hardware errata. + **/ +static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state) +{ + __e1000e_disable_aspm(pdev, state, 0); +} + +/** + * e1000e_disable_aspm_locked Disable ASPM states. + * @pdev: pointer to PCI device struct + * @state: bit-mask of ASPM states to disable + * + * This function must be called with pci_bus_sem acquired! + * Some devices *must* have certain ASPM states disabled per hardware errata. + **/ +static void e1000e_disable_aspm_locked(struct pci_dev *pdev, u16 state) +{ + __e1000e_disable_aspm(pdev, state, 1); +} + #ifdef CONFIG_PM static int __e1000_resume(struct pci_dev *pdev) {
@@ -6435,7 +6465,7 @@ static int __e1000_resume(struct pci_dev *pdev) if (adapter->flags2 & FLAG2_DISABLE_ASPM_L1) aspm_disable_flag |= PCIE_LINK_STATE_L1; if (aspm_disable_flag) - e1000e_disable_aspm(pdev, aspm_disable_flag); + e1000e_disable_aspm_locked(pdev, aspm_disable_flag); pci_set_master(pdev);
--
2.4.3