scsi: hisi_sas: Flush workqueue in hisi_sas_v3_remove()

mainline inclusion
from mainline-master
commit 6834ec8b
category: bugfix
bugzilla: 175270
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6834ec8b23c3eb345936022d46179b9d371e2344

------------------------------------------------------------------------

If the controller reset occurs at the same time as driver removal, it may
be possible that the interrupts have been released prior to the host
softreset, and calling pci_irq_vector() there causes a WARN:

WARNING: CPU: 37 PID: 1542 /pci/msi.c:1275 pci_irq_vector+0xc0/0xd0
Call trace:
pci_irq_vector+0xc0/0xd0
disable_host_v3_hw+0x58/0x5b0 [hisi_sas_v3_hw]
soft_reset_v3_hw+0x40/0xc0 [hisi_sas_v3_hw]
hisi_sas_controller_reset+0x150/0x260 [hisi_sas_main]
hisi_sas_rst_work_handler+0x3c/0x58 [hisi_sas_main]

To fix, flush the driver workqueue prior to releasing the interrupts to
ensure any resets have been completed.

Link: https://lore.kernel.org/r/1611659068-131975-5-git-send-email-john.garry@huawei.comSigned-off-by: NLuo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NOuyangdelong <ouyangdelong@huawei.com>
Signed-off-by: NNifujia <nifujia1@hisilicon.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/scsi/hisi_sas/hisi_sas_v3_hw.c

@@ -4573,6 +4573,7 @@ static void hisi_sas_v3_remove(struct pci_dev *pdev)
 		del_timer(&hisi_hba->timer);
 
 	sas_unregister_ha(sha);
+	flush_workqueue(hisi_hba->wq);
 	sas_remove_host(sha->core.shost);
 
 	hisi_sas_v3_destroy_irqs(pdev, hisi_hba);