| Message ID | 20201218204354.586951-7-a.darwish@linutronix.de |
|---|---|
| State | Superseded |
| Headers | show |
| Series | scsi: libsas: Remove in_interrupt() check | expand |
diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c index 69684c80c407..6244981a3ebf 100644 --- a/drivers/scsi/isci/port.c +++ b/drivers/scsi/isci/port.c @@ -164,7 +164,9 @@ static void isci_port_bc_change_received(struct isci_host *ihost, "%s: isci_phy = %p, sas_phy = %p\n", __func__, iphy, &iphy->sas_phy); - ihost->sas_ha.notify_port_event(&iphy->sas_phy, PORTE_BROADCAST_RCVD); + ihost->sas_ha.notify_port_event_gfp(&iphy->sas_phy, + PORTE_BROADCAST_RCVD, + GFP_ATOMIC); sci_port_bcn_enable(iport); }
Use the new libsas event notifiers API, which requires callers to explicitly pass the gfp_t memory allocation flags. The libsas ->notify_port_event() hook is called from isci_port_bc_change_received(). Below is the context analysis for all of its call chains: host.c: sci_controller_error_handler(): atomic, irq handler (*) OR host.c: sci_controller_completion_handler(), atomic, tasklet (*) -> sci_controller_process_completions() -> sci_controller_event_completion() -> phy.c: sci_phy_event_handler() -> port.c: sci_port_broadcast_change_received() -> isci_port_bc_change_received() host.c: isci_host_init() (@) spin_lock_irq(isci_host::scic_lock) -> sci_controller_initialize(), atomic (*) -> port_config.c: sci_port_configuration_agent_initialize() -> sci_mpc_agent_validate_phy_configuration() -> port.c: sci_port_add_phy() -> sci_port_set_phy() -> phy.c: sci_phy_set_port() -> port.c: sci_port_broadcast_change_received() -> isci_port_bc_change_received() port_config.c: apc_agent_timeout(), atomic, timer callback (*) -> sci_apc_agent_configure_ports() -> port.c: sci_port_add_phy() -> sci_port_set_phy() -> phy.c: sci_phy_set_port() -> port.c: sci_port_broadcast_change_received() -> isci_port_bc_change_received() phy.c: enter SCI state: *SCI_PHY_STOPPED* # Cont. from [1] -> sci_phy_stopped_state_enter() -> host.c: sci_controller_link_down() -> ->link_down_handler() == port_config.c: sci_apc_agent_link_down() -> port.c: sci_port_remove_phy() -> sci_port_clear_phy() -> phy.c: sci_phy_set_port() -> port.c: sci_port_broadcast_change_received() -> isci_port_bc_change_received() phy.c: enter SCI state: *SCI_PHY_STARTING* # Cont. from [2] -> sci_phy_starting_state_enter() -> host.c: sci_controller_link_down() -> ->link_down_handler() == port_config.c: sci_apc_agent_link_down() -> port.c: sci_port_remove_phy() -> sci_port_clear_phy() -> phy.c: sci_phy_set_port() -> port.c: sci_port_broadcast_change_received() -> isci_port_bc_change_received() [1] Call chains for entering state: *SCI_PHY_STOPPED* ----------------------------------------------------- host.c: isci_host_init() (@) spin_lock_irq(isci_host::scic_lock) -> sci_controller_initialize(), atomic (*) -> phy.c: sci_phy_initialize() -> phy.c: sci_phy_link_layer_initialization() -> phy.c: sci_change_state(SCI_PHY_STOPPED) init.c: PCI ->remove() || PM_OPS ->suspend, process context (+) -> host.c: isci_host_deinit() -> sci_controller_stop_phys() -> phy.c: sci_phy_stop() -> sci_change_state(SCI_PHY_STOPPED) phy.c: isci_phy_control() spin_lock_irqsave(isci_host::scic_lock, ) -> sci_phy_stop(), atomic (*) -> sci_change_state(SCI_PHY_STOPPED) [2] Call chains for entering state: *SCI_PHY_STARTING* ------------------------------------------------------ phy.c: phy_sata_timeout(), atimer, timer callback (*) spin_lock_irqsave(isci_host::scic_lock, ) -> sci_change_state(SCI_PHY_STARTING) host.c: phy_startup_timeout(), atomic, timer callback (*) spin_lock_irqsave(isci_host::scic_lock, ) -> sci_controller_start_next_phy() -> sci_phy_start() -> sci_change_state(SCI_PHY_STARTING) host.c: isci_host_start() (@) spin_lock_irq(isci_host::scic_lock) -> sci_controller_start(), atomic (*) -> sci_controller_start_next_phy() -> sci_phy_start() -> sci_change_state(SCI_PHY_STARTING) phy.c: Enter SCI state *SCI_PHY_SUB_FINAL* # Cont. from [2A] -> sci_change_state(SCI_PHY_SUB_FINAL) -> sci_phy_starting_final_substate_enter() -> sci_change_state(SCI_PHY_READY) -> Enter SCI state: *SCI_PHY_READY* -> sci_phy_ready_state_enter() -> host.c: sci_controller_link_up() -> sci_controller_start_next_phy() -> sci_phy_start() -> sci_change_state(SCI_PHY_STARTING) phy.c: sci_phy_event_handler(), atomic, discussed earlier (*) -> sci_change_state(SCI_PHY_STARTING), 11 instances port.c: isci_port_perform_hard_reset() spin_lock_irqsave(isci_host::scic_lock, ) -> port.c: sci_port_hard_reset(), atomic (*) -> phy.c: sci_phy_reset() -> sci_change_state(SCI_PHY_RESETTING) -> enter SCI PHY state: *SCI_PHY_RESETTING* -> sci_phy_resetting_state_enter() -> sci_change_state(SCI_PHY_STARTING) [2A] Call chains for entering SCI state: *SCI_PHY_SUB_FINAL* ------------------------------------------------------------ host.c: power_control_timeout(), atomic, timer callback (*) spin_lock_irqsave(isci_host::scic_lock, ) -> phy.c: sci_phy_consume_power_handler() -> phy.c: sci_change_state(SCI_PHY_SUB_FINAL) host.c: sci_controller_error_handler(): atomic, irq handler (*) OR host.c: sci_controller_completion_handler(), atomic, tasklet (*) -> sci_controller_process_completions() -> sci_controller_unsolicited_frame() -> phy.c: sci_phy_frame_handler() -> sci_change_state(SCI_PHY_SUB_AWAIT_SAS_POWER) -> sci_phy_starting_await_sas_power_substate_enter() -> host.c: sci_controller_power_control_queue_insert() -> phy.c: sci_phy_consume_power_handler() -> sci_change_state(SCI_PHY_SUB_FINAL) -> sci_change_state(SCI_PHY_SUB_FINAL) -> sci_controller_event_completion() -> phy.c: sci_phy_event_handler() -> sci_phy_start_sata_link_training() -> sci_change_state(SCI_PHY_SUB_AWAIT_SATA_POWER) -> sci_phy_starting_await_sata_power_substate_enter -> host.c: sci_controller_power_control_queue_insert() -> phy.c: sci_phy_consume_power_handler() -> sci_change_state(SCI_PHY_SUB_FINAL) As can be seen from the "(*)" markers above, almost all the call-chains are atomic. The only exception, marked with "(+)", is a PCI ->remove() and PM_OPS ->suspend() cold path. Thus, pass GFP_ATOMIC to the libsas port event notifier. Note, the now-replaced libsas APIs used in_interrupt() to implicitly decide which memory allocation type to use. This was only partially correct, as it fails to choose the correct GFP flags when just preemption or interrupts are disabled. Such buggy code paths are marked with "(@)" in the call chains above. Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Cc: stable@vger.kernel.org Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com> --- drivers/scsi/isci/port.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)