On Tue, Jun 21, 2022 at 11:56 PM Khalid Aziz [off-list ref] wrote:

quoted

      while ((comp_code = next_inbox->comp_code) != BLOGIC_INBOX_FREE) {
-             /*
-                We are only allowed to do this because we limit our
-                architectures we run on to machines where bus_to_virt(
-                actually works.  There *needs* to be a dma_addr_to_virt()
-                in the new PCI DMA mapping interface to replace
-                bus_to_virt() or else this code is going to become very
-                innefficient.
-              */
-             struct blogic_ccb *ccb =
-                     (struct blogic_ccb *) bus_to_virt(next_inbox->ccb);
+             struct blogic_ccb *ccb = blogic_inbox_to_ccb(adapter, adapter->next_inbox);

This change looks good enough as workaround to not use bus_to_virt() for
now. There are two problems I see though. One, I do worry about
blogic_inbox_to_ccb() returning NULL for ccb which should not happen
unless the mailbox pointer was corrupted which would indicate a bigger
problem. Nevertheless a NULL pointer causing kernel panic concerns me.
How about adding a check before we dereference ccb?

Right, makes sense

Second, with this patch applied, I am seeing errors from the driver:

=====================
[ 1623.902685]  sdb: sdb1 sdb2
[ 1623.903245] sd 2:0:0:0: [sdb] Attached SCSI disk
[ 1623.911000] scsi2: Illegal CCB #76 status 2 in Incoming Mailbox
[ 1623.911005] scsi2: Illegal CCB #76 status 2 in Incoming Mailbox
[ 1623.911070] scsi2: Illegal CCB #79 status 2 in Incoming Mailbox
[ 1651.458008] scsi2: Warning: Partition Table appears to have Geometry
256/63 which is
[ 1651.458013] scsi2: not compatible with current BusLogic Host Adapter
Geometry 255/63
[ 1658.797609] scsi2: Resetting BusLogic BT-958D Failed
[ 1659.533208] sd 2:0:0:0: Device offlined - not ready after error recovery
[ 1659.533331] sd 2:0:0:0: Device offlined - not ready after error recovery
[ 1659.533333] sd 2:0:0:0: Device offlined - not ready after error recovery
[ 1659.533342] sd 2:0:0:0: [sdb] tag#101 FAILED Result:
hostbyte=DID_TIME_OUT driverbyte=DRIVER_OK cmd_age=35s
[ 1659.533345] sd 2:0:0:0: [sdb] tag#101 CDB: Read(10) 28 00 00 00 00 28
00 00 10 00
[ 1659.533346] I/O error, dev sdb, sector 40 op 0x0:(READ) flags 0x80700
phys_seg 1 prio class 0

=================

This is on VirtualBox using emulated BusLogic adapter.

This patch needs more refinement.

Thanks for testing the patch, too bad it didn't work. At least I quickly found
one stupid mistake on my end, hope it's the only one.

Can you test it again with this patch on top?

diff --git a/drivers/scsi/BusLogic.c b/drivers/scsi/BusLogic.c
index d057abfcdd5c..9e67f2ee25ee 100644
--- a/drivers/scsi/BusLogic.c
+++ b/drivers/scsi/BusLogic.c

@@ -2554,8 +2554,14 @@ static void blogic_scan_inbox(struct

blogic_adapter *adapter)
        enum blogic_cmplt_code comp_code;

        while ((comp_code = next_inbox->comp_code) != BLOGIC_INBOX_FREE) {
-               struct blogic_ccb *ccb = blogic_inbox_to_ccb(adapter,
adapter->next_inbox);
-               if (comp_code != BLOGIC_CMD_NOTFOUND) {
+               struct blogic_ccb *ccb = blogic_inbox_to_ccb(adapter,
next_inbox);
+               if (!ccb) {
+                       /*
+                        * This should never happen, unless the CCB list is
+                        * corrupted in memory.
+                        */
+                       blogic_warn("Could not find CCB for dma
address 0x%x\n", adapter, next_inbox->ccb);
+               } else if (comp_code != BLOGIC_CMD_NOTFOUND) {
                        if (ccb->status == BLOGIC_CCB_ACTIVE ||
                                        ccb->status == BLOGIC_CCB_RESET) {