Subject: is PT_STACKSIZE too small?
To: None <firstname.lastname@example.org>
From: T.SHIOZAKI <email@example.com>
Date: 06/24/2003 19:47:29
Emacs-21.3 frequently (but random) crashes on the recent
NetBSD/i386 current + X (configured with ThreadedX=yes).
Emacs seems to crash when it catch a key event of X while
garbage collection. Additionally, Mozilla has crashed similarly.
The crash information of Emacs is here:
% gdb /usr/pkg/bin/emacs emacs.core
GNU gdb 5.0nb1
Copyright 2000 Free Software Foundation, Inc.
Core was generated by `emacs'.
Program terminated with signal 4, Illegal instruction.
(gdb) info registers
eax 0x0 0
ecx 0x5 5
edx 0x582dc5a4 1479394724
ebx 0x0 0
esp 0xbfbc1f80 0xbfbc1f80
ebp 0xbfbeef9c 0xbfbeef9c
esi 0x833d7ac 137615276
edi 0x5 5
eip 0x80d62f9 0x80d62f9
eflags 0x10282 66178
Look at esp register. This value is on the redzone of the stack.
the stack is surely overflowing, although I can not understand
why this causes SIGILL.
Emacs is stabilized when PT_STACKSIZE is increased to 1<<20.
I guess we should improve the implementation around per-thread stack,
but it requires time.
Thus, we need to set PT_STACKSIZE appropriately for the present.
Anyway, I guess the current value of PT_STACKSIZE, 1<<18, is too small
for me to live on the -current :-)
How much is suitable value of PT_STACKSIZE?
# Of course, this value changes with architecture and usage.
# How about making PT_STACKSIZE configurable in mk.conf or something?