Commit beb9e315 authored by Joe Lawrence's avatar Joe Lawrence Committed by Christoph Hellwig
Browse files

qla2xxx: Prevent removal and board_disable race 



Introduce mutual exclusion between the qla2xxx_remove_one PCI driver
callback and qla2x00_disable_board_on_pci_error, which is scheduled as
board_disable work by qla2x00_check_reg{32,16}_for_disconnect:

* Leave the driver-specific data attached to the underlying PCI device
intact in qla2x00_disable_board_on_pci_error, so that qla2x00_remove_one
has enough breadcrumbs to determine that any board_disable work has been
completed.

* In qla2xxx_remove_one, set a bit to prevent any subsequent
board_disable work from scheduling, then cancel and wait until pending
work has completed.

* Reuse the PCI device enable count check in qla2x00_remove_one to
determine if board_disable has occured. The original purpose of this
check was unnecessary since the driver remove function wasn't called
when the probe fails.

Signed-off-by: default avatarJoe Lawrence <joe.lawrence@stratus.com>
Acked-by: default avatarChad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 232792b6

drivers/scsi/qla2xxx/qla_def.h

+1 −0
Original line number Diff line number Diff line
@@ -3404,6 +3404,7 @@ typedef struct scsi_qla_host { 


	unsigned long	pci_flags;

#define PFLG_DISCONNECTED	0	/* PCI device removed */

#define PFLG_DRIVER_REMOVING	1	/* PCI driver .remove */



	uint32_t	device_flags;

#define SWITCH_FOUND		BIT_0

drivers/scsi/qla2xxx/qla_isr.c

+2 −1
Original line number Diff line number Diff line
@@ -117,7 +117,8 @@ qla2x00_check_reg32_for_disconnect(scsi_qla_host_t *vha, uint32_t reg) 
{

	/* Check for PCI disconnection */

	if (reg == 0xffffffff) {

		if (!test_and_set_bit(PFLG_DISCONNECTED, &vha->pci_flags)) {

		if (!test_and_set_bit(PFLG_DISCONNECTED, &vha->pci_flags) &&

		    !test_bit(PFLG_DRIVER_REMOVING, &vha->pci_flags)) {

			/*

			 * Schedule this (only once) on the default system

			 * workqueue so that all the adapter workqueues and the

drivers/scsi/qla2xxx/qla_os.c

+19 −12
Original line number Diff line number Diff line
@@ -3131,15 +3131,25 @@ qla2x00_remove_one(struct pci_dev *pdev) 
	scsi_qla_host_t *base_vha;

	struct qla_hw_data  *ha;



	base_vha = pci_get_drvdata(pdev);

	ha = base_vha->hw;



	/* Indicate device removal to prevent future board_disable and wait

	 * until any pending board_disable has completed. */

	set_bit(PFLG_DRIVER_REMOVING, &base_vha->pci_flags);

	cancel_work_sync(&ha->board_disable);



	/*

	 * If the PCI device is disabled that means that probe failed and any

	 * resources should be have cleaned up on probe exit.

	 * If the PCI device is disabled then there was a PCI-disconnect and

	 * qla2x00_disable_board_on_pci_error has taken care of most of the

	 * resources.

	 */

	if (!atomic_read(&pdev->enable_cnt))

	if (!atomic_read(&pdev->enable_cnt)) {

		scsi_host_put(base_vha->host);

		kfree(ha);

		pci_set_drvdata(pdev, NULL);

		return;



	base_vha = pci_get_drvdata(pdev);

	ha = base_vha->hw;

	}



	qla2x00_wait_for_hba_ready(base_vha);
@@ -4799,18 +4809,15 @@ qla2x00_disable_board_on_pci_error(struct work_struct *work) 
	qla82xx_md_free(base_vha);

	qla2x00_free_queues(ha);



	scsi_host_put(base_vha->host);



	qla2x00_unmap_iobases(ha);



	pci_release_selected_regions(ha->pdev, ha->bars);

	kfree(ha);

	ha = NULL;



	pci_disable_pcie_error_reporting(pdev);

	pci_disable_device(pdev);

	pci_set_drvdata(pdev, NULL);



	/*

	 * Let qla2x00_remove_one cleanup qla_hw_data on device removal.

	 */

}



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