kern/116669: Parallel port printing crashes CURRENT

[Serguey Grigoriev]

>Number:         116669
>Category:       kern
>Synopsis:       Parallel port printing crashes CURRENT
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Sep 26 17:40:07 GMT 2007
>Closed-Date:
>Last-Modified:
>Originator:     Serguey Grigoriev
>Release:        7-CURRENT amd64
>Organization:
PCN JSC
>Environment:
FreeBSD amico.pcn.su 7.0-CURRENT FreeBSD 7.0-CURRENT #1: Wed Sep 26 11:24:13 MSD 2007     root at amico.pcn.su:/usr/obj/usr/src/sys/SMPALTQ  amd64
>Description:
my 7-Current amd64 system panics during sending print jobs to LPT connected printers. I've found this problem at the beginning of May. Kernels compiled with April or older sources still work fine.

Panic screens look like this:

panic: bad stray interrupt
cpuid = 0
KDB: enter: panic
[thread pid = 11 tid 100002 ]
Stopped at kdb_enter+0x2f: leave

The call stack trace is:

Tracing pid 11 tid 100002 td 0xffffff003db84990
kdb_enter() at kdb_enter+0x30
intr_execute_handlers() at intr_execute_handlers+0x183
Xapic_isr1() at Xapic_isr1()+0x7f
--- interrupt, rip = 0xffffffff8071ec56, rsp = 0xffffffffa075fbd0, rbp > = 0xffffffffa075fbe0 ---
acpi_cpu_c1() at acpi_cpu_c1+0x6
acpi_cpu_idle() at acpi_cpu_idle+0x27c
sched_idletd() at sched_idletd+0x35
fork_exit() at fork_exit+0x153
fork_trampoline() at fork_trampoline+0xe
--- trap 0, rip = 0, rsp = 0xffffffffa075fd30, rbp = 0 ---

There is a workaround. If LPT ports are switched to the polling mode the system does not crash but becomes less interactive. For example the mouse pointer is periodically (during sending print jobs over LPT) blocked on the screen for a few seconds.

>How-To-Repeat:
This problem repeats every time I print not tiny files.
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: