Re: Re: Serial driver problems with 5.2-current

Hello Warner.

This is what i get on the console before it hangs.
==
sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
sio0: type 16550A
sio1 at port 0x2f8-0x2ff irq 3 on isa0
sio1: type 16550A
sio4: <3Com MegaHertz 3CCFEM556B> at port 0x120-0x127 irq 11 function 1 config 3 9 on pccard1
sio4: type 16550A with a buggy IIR_TXRDY implementation
sio4: unable to activate interrupt in fast mode - using normal mode
sio4 : spouting nonsense -- disabled. 
==

Is it possible that somehow the IRQ supposed for the ep0 is somehow getting into the sio4 handler ?

dheeraj

PS: The machine still hangs because it still gets into that offending while loop.

-----Original Message-----
From: "M. Warner Losh" <imp_at_bsdimp.com>
To: dhee_at_myrealbox.com
Date: Sat, 27 Dec 2003 10:04:17 -0700 (MST)
Subject: Re: Serial driver problems with 5.2-current

In message: <1072530641.b36949c0dhee_at_myrealbox.com>
            "Dheeraj" <dhee_at_myrealbox.com> writes:
: Hello Warner.
: 
: I got a little further ahead or maybe not.
: i just put in a bunch of printf's and noticed that it goes into an infinite loop. in
: 
: srs/sys/dev/sio.c
: 
: siointr1(struct com_s com) 
: {
: 
: in the 2nd while loop
:  while(line_status & LSR_RCV_MASK) {
:        /*break/unattached error bits or real input?*/
:    ----
:     ---
:  }
: }

: so it never comes out of this loop and the machine just hangs. i
: could also point to some more details if i were able to see the
: 'printfs' properly, right now i can see the scrreen scroll so fast
: that i can't make anything out of it. and as i said earlier i cannot
: break into the debugger. (i know only two ways of it, ctrl-alt-esc
: and sysctl, if there is anything else i can try out i shall try)

Very interesting.  You are attaching to a uart that potentially isn't
there for reasons unknown.  Not sure which interrupt is involved (we
should make a ddb command show active interrupts).

Please try this patch and report back what it says.

Warner