Bug 161274

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User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.8) Gecko/20050513 Galeon/1.3.21

Description of problem:
Kernel hangs with (roughly): 

not syncing. drivers/serial/8250.c (32xx) spin_is_locked on uninitialised spinlock

The call path is (roughly):

<panic path>
serial8250_startup
uart_status
uart_open
tty_open
<VFS call path>

I'm guessing it's the spin_lock_irqsave in serial8250_startup.

I can reproduce this reliably by starting cups, which (annoyingly) tries to open serial devices for no good reason. Or alternatively with 'setserial /dev/ttyS0'. This happens with the kernel-2.6.11-1.35_FC3 kernel too, it doesnt happen with the kernel-2.6.9-1.681_FC3 kernel.

The machine is a Sony Vaio PCG-C1F, Pentium 266MMX. lspci -v:

00:00.0 Host bridge: Intel Corporation 430TX - 82439TX MTXC (rev 01)

# cat /proc/interrupts 
           CPU0       
  0:    1925081          XT-PIC  timer
  1:          8          XT-PIC  i8042
  2:          0          XT-PIC  cascade
  3:      12326          XT-PIC  0.0
  5:          1          XT-PIC  ES1688
  8:          1          XT-PIC  rtc
  9:         32          XT-PIC  acpi, uhci_hcd:usb1, yenta
 12:        110          XT-PIC  i8042
 14:       6858          XT-PIC  ide0
NMI:          0 
ERR:          0

The problem appears to be because there is a pcmcia PRISM-I card on IRQ 3.

# cat /sys/class/tty/ttyS0/device/resources 
state = active
io 0x3f8-0x3ff

# cardctl config
Socket 0:
  Vcc 3.3V  Vpp1 0.0V  Vpp2 0.0V
  interface type is "memory and I/O"
  irq 3 [exclusive] [level]
  function 0:
    config base 0x03e0
      option 0x41
    io 0x0100-0x013f [16bit]

I can't disable ttyS0, dmesg startup shows:

PNP: PS/2 Controller [PNP0303:KBC,PNP0f13:MOUE] at 0x60,0x64 irq 1,12
serio: i8042 AUX port at 0x60,0x64 irq 12
serio: i8042 KBD port at 0x60,0x64 irq 1
Serial: 8250/16550 driver $Revision: 1.90 $ 76 ports, IRQ sharing enabled
ttyS2 at I/O 0x3e8 (irq = 4) is a 16550A
pnp: Device 00:09 activated.
ttyS0 at I/O 0x3f8 (irq = -1) is a 16550A

If I try disable via PNP:

# echo disable > /sys/class/tty/ttyS0/device/resources
# dmesg |tail -1
pnp: Device 00:09 cannot be configured because it is in use.

I've tried various boot options, such as pci=usepirqmask, pci=routeirq, acpi=off, acpi=on. I've tried BIOS options like PNP OS = yes and no, but no difference unfortunately. There is no option to disable ttyS0 in the BIOS because this machine does not have a serial port. It has only the IRDA port, which is detected as ttyS2 in the dmesg above (despite it being set in the BIOS to COM1 settings - and yes, i've tried with IRDA disabled).

Is there a way to tell linux /dev/ttyS0 does not exist?


Version-Release number of selected component (if applicable):
kernel-2.6.11-1.1369_FC4

How reproducible:
Always

Steps to Reproduce:
1. Boot kernel-2.6.11-1.1369_FC4 or kernel-2.6.11-1.35_FC3
2. setserial /dev/ttyS0 or start cups.
3. panic with spin_is_locked on unitialised spinlock
  

Actual Results:  panic

Expected Results:  nothing. machine should not have panic'd.


Additional info: