From: Igor Pylypiv <ipylypiv@xxxxxxxxxx> commit 653926205741add87a6cf452e21950eebc6ac10b upstream. Calling scsi_remove_host() before scsi_add_host() results in a crash: BUG: kernel NULL pointer dereference, address: 0000000000000108 RIP: 0010:device_del+0x63/0x440 Call Trace: device_unregister+0x17/0x60 scsi_remove_host+0xee/0x2a0 pm8001_pci_probe+0x6ef/0x1b90 [pm80xx] local_pci_probe+0x3f/0x90 We cannot call scsi_remove_host() in pm8001_alloc() because scsi_add_host() has not been called yet at that point in time. Function call tree: pm8001_pci_probe() | `- pm8001_pci_alloc() | | | `- pm8001_alloc() | | | `- scsi_remove_host() | `- scsi_add_host() Link: https://lore.kernel.org/r/20211201041627.1592487-1-ipylypiv@xxxxxxxxxx Fixes: 05c6c029a44d ("scsi: pm80xx: Increase number of supported queues") Reviewed-by: Vishakha Channapattan <vishakhavc@xxxxxxxxxx> Acked-by: Jack Wang <jinpu.wang@xxxxxxxxx> Signed-off-by: Igor Pylypiv <ipylypiv@xxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/pm8001/pm8001_init.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) --- a/drivers/scsi/pm8001/pm8001_init.c +++ b/drivers/scsi/pm8001/pm8001_init.c @@ -281,12 +281,12 @@ static int pm8001_alloc(struct pm8001_hb if (rc) { pm8001_dbg(pm8001_ha, FAIL, "pm8001_setup_irq failed [ret: %d]\n", rc); - goto err_out_shost; + goto err_out; } /* Request Interrupt */ rc = pm8001_request_irq(pm8001_ha); if (rc) - goto err_out_shost; + goto err_out; count = pm8001_ha->max_q_num; /* Queues are chosen based on the number of cores/msix availability */ @@ -422,8 +422,6 @@ static int pm8001_alloc(struct pm8001_hb pm8001_tag_init(pm8001_ha); return 0; -err_out_shost: - scsi_remove_host(pm8001_ha->shost); err_out_nodev: for (i = 0; i < pm8001_ha->max_memcnt; i++) { if (pm8001_ha->memoryMap.region[i].virt_ptr != NULL) {