[hatari-devel] Latest Hatari HG version gets stuck sometimes

[Eero Tamminen]

Hi,

Nicolas, could this be related to your recent video.c changes?

For some reason Hatari seems now to sometimes get stuck looping here
(doesn't update its screen, uses 100% CPU etc):
-----------------
1736            while ( ( PendingInterruptCount <= 0 ) && ( 
PendingInterruptFunction ) && ( ( regs.spcflags & SPCFLAG_STOP ) == 0 ) )
(gdb) next
1738                CALL_VAR(PendingInterruptFunction);         /* call the 
interrupt handler */
(gdb) next
1739                do_specialties_interrupt ( FALSE );         /* test if 
there's an mfp/video interrupt and add non pending jitter */
-----------------

It will never exit this loop.


At that point, PendingInterruptCount doesn't anymore change, it
keeps at the same value:
------------------
(gdb) print PendingInterruptCount
$3 = -76800
(gdb) print ActiveInterrupt
$4 = 3
(gdb) print regs.spcflags
$5 = 0
------------------

The value can change between different Hatari runs though:
------------------
(gdb) print PendingInterruptCount
$1 = -115200
(gdb) print PendingInterruptFunction
$2 = (void (*)(void)) 0x8075690 <Video_InterruptHandler_EndLine>
(gdb) cont
Continuing.
^C
Program received signal SIGINT, Interrupt.
[Switching to Thread 0xb79506b0 (LWP 4982)]
0x08060d53 in Int_AcknowledgeInterrupt () at int.c:292
292                             InterruptHandlers[i].Cycles -= 
CycleSubtract;
(gdb) print PendingInterruptCount
$3 = -115200
------------------

Mostly the backtrace is this:
------------------
(gdb) bt
#0  Int_AcknowledgeInterrupt () at int.c:266
#1  0x080756bb in Video_InterruptHandler_EndLine () at video.c:1642
#2  0x0807c3b9 in m68k_go (may_quit=1) at newcpu.c:1738
#3  0x08063bc9 in M68000_Start () at m68000.c:224
#4  0x08064709 in main (argc=6, argv=Cannot access memory at address 0x4
) at main.c:712
------------------

This issue can be triggered by running Hatari with ST TOS and:
	/hatari -m --fast-forward 1 --frameskips 0

And after desktop comes up, toggling Pause on/off half a dozen times.
If you don't get this, re-run Hatari and try again.

(Pause/Unpause doesn't have or call anything related to interrupt handling.)

"make distclean && make" didn't help.


	- Eero