scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc()

stable inclusion
from stable-v5.10.85
commit 1e434d2687e8bc0b3cdc9dd093c0e9047c0b4add
bugzilla: 186032 https://gitee.com/openeuler/kernel/issues/I4QVI4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1e434d2687e8bc0b3cdc9dd093c0e9047c0b4add

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

commit 65392620 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@google.com
Fixes: 05c6c029 ("scsi: pm80xx: Increase number of supported queues")
Reviewed-by: NVishakha Channapattan <vishakhavc@google.com>
Acked-by: NJack Wang <jinpu.wang@ionos.com>
Signed-off-by: NIgor Pylypiv <ipylypiv@google.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/scsi/pm8001/pm8001_init.c

@@ -280,12 +280,12 @@ static int pm8001_alloc(struct pm8001_hba_info *pm8001_ha,
 	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 */
@@ -419,8 +419,6 @@ static int pm8001_alloc(struct pm8001_hba_info *pm8001_ha,
 	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) {