A bit more debugging information. Gdb shows that ./linux segfaults
at the same location in os_early_checks () at arch/um/os-Linux/start_up.c:264
no matter CONFIG_HOST_2G_2G is defined or not. Any clue how to fix?
See my earlier email below for my kernel settings. Thanks for your help.
# gdb ./linux
GNU gdb Red Hat Linux (220.127.116.11-1.63rh)
Copyright 2004 Free Software Foundation, Inc.
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This GDB was configured as "x86_64-redhat-linux-gnu"...Using host libthread_db library "/lib64/tls/libthread_db.so.1".
Starting program: /root/linux-18.104.22.168/linux
Program received signal SIGSEGV, Segmentation fault.
_raw_spin_lock (lock=0x602bfb70) at include/asm/thread_info.h:47
#0 _raw_spin_lock (lock=0x602bfb70) at include/asm/thread_info.h:47
#1 0x000000006020de18 in _spin_lock_irqsave (lock=0x602bfb70)
#2 0x000000006002d777 in vprintk (
fmt=0x60234ee8 "Checking that ptrace can change system call numbers...",
args=0x7fbffff470) at kernel/printk.c:540
#3 0x000000006002d730 in printk (fmt=Variable "fmt" is not available.
) at kernel/printk.c:516
#4 0x0000000060026989 in os_early_checks () at arch/um/os-Linux/start_up.c:264
#5 0x0000000060019e7f in linux_main (argc=1, argv=0x7fbffff908)
#6 0x0000000060012fda in main (argc=1, argv=0x7fbffff908, envp=0x7fbffff918)
Puzzled and need some help.
I downloaded the stock linux-22.214.171.124.tar.bz2, and
tried to make ARCH=um on RedHat's Enterprise Linux 4 update 2. And the output segfaults immediately.
My procedures are as follows:
1) cd linux-126.96.36.199
2) make menuconfig ARCH=um
2a) enable CONFIG_HOST_2G_2G, or
2b) disable CONFIG_HOST_2G_2G
and accept all other defaults.
3) make linux ARCH=um
4) ./linux --> immediate segfault (for both config 2a and 2b)
My RHEL4 update 2 is running kernel-2.6.9-22.EL.
I tried many many other prebuilt binaries from various
sites. Most of them fail. What should I do to make it work?