Re: kern/46225: printing to /dev/lpt0 hangs in lptwrite(), probably lptwrite2

[Petar Bogdanovic <petar%smokva.net@localhost>]

The following reply was made to PR kern/46225; it has been noted by GNATS.

From: Petar Bogdanovic <petar%smokva.net@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/46225: printing to /dev/lpt0 hangs in lptwrite(), probably
 lptwrite2
Date: Tue, 20 Mar 2012 23:59:18 +0100

 On Tue, Mar 20, 2012 at 10:25:07PM +0000, Christos Zoulas wrote:
 >
 > Or see if the interrupt handler can be fixed.
 
 lptintr or tpm_intr?  I was rather looking into intr.c with INTRDEBUG
 defined but the table from intr_printconfig didn't seem complete so I
 gave up:
 
     (...)
     cpu0 source 0 is pin 9 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 1 is pin 19 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 2 is pin 20 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
             handler 0xffffffff80454aa1 level 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 3 is pin 21 from pic ioapic0 maxlevel 7
             handler 0xffffffff80320828 level 7
             handler 0xffffffff80454aa1 level 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 4 is pin 22 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 5 is pin 14 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 6 is pin 15 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 7 is pin 7 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
             handler 0xffffffff80454aa1 level 6
     cpu0 source 8 is pin 4 from pic ioapic0 maxlevel 8
             handler 0xffffffff8024d493 level 8
     cpu0 source 9 is pin 6 from pic ioapic0 maxlevel 6
             handler 0xffffffff80454aa1 level 6
     (...)
 
 When looked up in ddb, all addresses point to some unrelated handlers
 but none of them to lptintr or tpm_intr (no matter if tpm was enabled
 or not).
 
 What was interesting though is that intr_printconfig didn't list any
 interrupt masks for cpu0 when lpt and tpm were enabled, both at irq 7.
 With tpm disabled, the listing returned:
 
     cpu0: interrupt masks:
     IPL 0 mask 1fffc00 unmask fe0003ff
     IPL 1 mask 3fffc00 unmask fc0003ff
     IPL 2 mask 7fffc00 unmask f80003ff
     IPL 3 mask ffffc00 unmask f00003ff
     IPL 4 mask 1ffffc00 unmask e00003ff
     IPL 5 mask 3ffffc00 unmask c00003ff
     IPL 6 mask 3ffffeff unmask c0000100
     IPL 7 mask 7ffffeff unmask 80000100
     IPL 8 mask ffffffff unmask 0
 
 Thats when I figured out I'm floating in the ocean.