From: Martin Diehl Seems there are two problems: * interrupt handler expects to find the host in aha152x_host[] array which is currently set too late after probing irq's * despite testing for NULL swintr derefences a shpnt==NULL anyway, looks like a victim of HOSTNO obfuscation ;-) The patch below fixes the issue for me - succesfully tested to compile, load and even use my attached scanner. drivers/scsi/aha152x.c | 15 ++++++++++----- 1 files changed, 10 insertions(+), 5 deletions(-) diff -puN drivers/scsi/aha152x.c~aha152x-oops-fix drivers/scsi/aha152x.c --- 25/drivers/scsi/aha152x.c~aha152x-oops-fix 2003-06-26 18:38:55.000000000 -0700 +++ 25-akpm/drivers/scsi/aha152x.c 2003-06-26 18:38:55.000000000 -0700 @@ -941,7 +941,8 @@ static irqreturn_t swintr(int irqno, voi struct Scsi_Host *shpnt = lookup_irq(irqno); if (!shpnt) { - printk(KERN_ERR "aha152x%d: catched software interrupt %d for unknown controller.\n", HOSTNO, irqno); + /* no point using HOSTNO here! */ + printk(KERN_ERR "aha152x: catched software interrupt %d for unknown controller.\n", irqno); return IRQ_NONE; } @@ -1049,6 +1050,10 @@ struct Scsi_Host *aha152x_probe_one(stru printk(KERN_INFO "aha152x%d: trying software interrupt, ", shost->host_no); + + /* need to have host registered before triggering any interrupt */ + aha152x_host[registered_count] = shost; + mb(); SETPORT(DMACNTRL0, SWINT|INTEN); mdelay(1000); free_irq(shost->irq, shost); @@ -1064,7 +1069,7 @@ struct Scsi_Host *aha152x_probe_one(stru printk(KERN_ERR "aha152x%d: IRQ %d possibly wrong. " "Please verify.\n", shost->host_no, shost->irq); - goto out_release_region; + goto out_unregister_host; } printk("ok.\n"); @@ -1077,12 +1082,12 @@ struct Scsi_Host *aha152x_probe_one(stru "aha152x", shost) < 0) { printk(KERN_ERR "aha152x%d: failed to reassign interrupt.\n", shost->host_no); - goto out_release_region; + goto out_unregister_host; } - - aha152x_host[registered_count] = shost; return shost; /* the pcmcia stub needs the return value; */ +out_unregister_host: + aha152x_host[registered_count] = NULL; out_release_region: release_region(shost->io_port, IO_RANGE); out_unregister: _