Hi,
 
    I had built 2.6.10 kernel without any patch as guest. The host kernel is 2.6.9-1.667(Fedora Core 3 's default kernel).  While running the UML in debug mode,  the gbd hang just after print ----- This GDB was configured as "i386-redhat-linux-gnu"...Using host libthread_db library "/lib/tls/libthread_db.so.1" ----- . What's wrong with it ? Thanks !
 
here my config file:
 
#
# Automatically generated make config: don't edit
# Linux kernel version: 2.6.10
# Sun Jan  9 21:02:14 2005
#
CONFIG_GENERIC_HARDIRQS=y
CONFIG_USERMODE=y
CONFIG_MMU=y
CONFIG_UID16=y
CONFIG_RWSEM_GENERIC_SPINLOCK=y
 
#
# UML-specific options
#
CONFIG_MODE_TT=y
CONFIG_MODE_SKAS=y
CONFIG_NET=y
CONFIG_BINFMT_ELF=y
CONFIG_BINFMT_MISC=y
# CONFIG_HOSTFS is not set
CONFIG_MCONSOLE=y
# CONFIG_HOST_2G_2G is not set
# CONFIG_SMP is not set
CONFIG_NEST_LEVEL=0
CONFIG_KERNEL_HALF_GIGS=1
CONFIG_KERNEL_STACK_ORDER=2
CONFIG_UML_REAL_TIME_CLOCK=y
 
#
# Code maturity level options
#
CONFIG_EXPERIMENTAL=y
CONFIG_CLEAN_COMPILE=y
CONFIG_BROKEN_ON_SMP=y
 
#
# General setup
#
CONFIG_LOCALVERSION=""
CONFIG_SWAP=y
CONFIG_SYSVIPC=y
# CONFIG_POSIX_MQUEUE is not set
CONFIG_BSD_PROCESS_ACCT=y
# CONFIG_BSD_PROCESS_ACCT_V3 is not set
CONFIG_SYSCTL=y
# CONFIG_AUDIT is not set
CONFIG_LOG_BUF_SHIFT=14
# CONFIG_HOTPLUG is not set
CONFIG_KOBJECT_UEVENT=y
# CONFIG_IKCONFIG is not set
# CONFIG_EMBEDDED is not set
CONFIG_KALLSYMS=y
# CONFIG_KALLSYMS_EXTRA_PASS is not set
CONFIG_FUTEX=y
CONFIG_EPOLL=y
# CONFIG_CC_OPTIMIZE_FOR_SIZE is not set
CONFIG_SHMEM=y
CONFIG_CC_ALIGN_FUNCTIONS=0
CONFIG_CC_ALIGN_LABELS=0
CONFIG_CC_ALIGN_LOOPS=0
CONFIG_CC_ALIGN_JUMPS=0
# CONFIG_TINY_SHMEM is not set
 
#
# Loadable module support
#
# CONFIG_MODULES is not set
 
#
# Generic Driver Options
#
CONFIG_STANDALONE=y
CONFIG_PREVENT_FIRMWARE_BUILD=y
 
#
# Character Devices
#
CONFIG_STDIO_CONSOLE=y
CONFIG_SSL=y
CONFIG_FD_CHAN=y
CONFIG_NULL_CHAN=y
CONFIG_PORT_CHAN=y
CONFIG_PTY_CHAN=y
CONFIG_TTY_CHAN=y
CONFIG_XTERM_CHAN=y
# CONFIG_NOCONFIG_CHAN is not set
CONFIG_CON_ZERO_CHAN="fd:0,fd:1"
CONFIG_CON_CHAN="xterm"
CONFIG_SSL_CHAN="pty"
CONFIG_UNIX98_PTYS=y
CONFIG_LEGACY_PTYS=y
CONFIG_LEGACY_PTY_COUNT=256
# CONFIG_WATCHDOG is not set
CONFIG_UML_SOUND=y
CONFIG_SOUND=y
CONFIG_HOSTAUDIO=y
 
#
# Block Devices
#
CONFIG_BLK_DEV_UBD=y
# CONFIG_BLK_DEV_UBD_SYNC is not set
CONFIG_BLK_DEV_COW_COMMON=y
CONFIG_BLK_DEV_LOOP=y
CONFIG_BLK_DEV_NBD=y
CONFIG_BLK_DEV_RAM=y
CONFIG_BLK_DEV_RAM_COUNT=16
CONFIG_BLK_DEV_RAM_SIZE=4096
CONFIG_BLK_DEV_INITRD=y
CONFIG_INITRAMFS_SOURCE=""
 
#
# IO Schedulers
#
CONFIG_IOSCHED_NOOP=y
CONFIG_IOSCHED_AS=y
CONFIG_IOSCHED_DEADLINE=y
CONFIG_IOSCHED_CFQ=y
CONFIG_NETDEVICES=y
 
#
# UML Network Devices
#
CONFIG_UML_NET=y
CONFIG_UML_NET_ETHERTAP=y
CONFIG_UML_NET_TUNTAP=y
CONFIG_UML_NET_SLIP=y
CONFIG_UML_NET_DAEMON=y
CONFIG_UML_NET_MCAST=y
CONFIG_UML_NET_SLIRP=y
 
#
# Networking support
#
 
#
# Networking options
#
CONFIG_PACKET=y
CONFIG_PACKET_MMAP=y
# CONFIG_NETLINK_DEV is not set
CONFIG_UNIX=y
CONFIG_NET_KEY=y
CONFIG_INET=y
# CONFIG_IP_MULTICAST is not set
CONFIG_IP_ADVANCED_ROUTER=y
# CONFIG_IP_MULTIPLE_TABLES is not set
# CONFIG_IP_ROUTE_MULTIPATH is not set
# CONFIG_IP_ROUTE_VERBOSE is not set
# CONFIG_IP_PNP is not set
# CONFIG_NET_IPIP is not set
# CONFIG_NET_IPGRE is not set
# CONFIG_ARPD is not set
# CONFIG_SYN_COOKIES is not set
CONFIG_INET_AH=y
CONFIG_INET_ESP=y
CONFIG_INET_IPCOMP=y
CONFIG_INET_TUNNEL=y
CONFIG_IP_TCPDIAG=y
# CONFIG_IP_TCPDIAG_IPV6 is not set
 
#
# IP: Virtual Server Configuration
#
# CONFIG_IP_VS is not set
# CONFIG_IPV6 is not set
CONFIG_NETFILTER=y
# CONFIG_NETFILTER_DEBUG is not set
 
#
# IP: Netfilter Configuration
#
CONFIG_IP_NF_CONNTRACK=y
# CONFIG_IP_NF_CT_ACCT is not set
CONFIG_IP_NF_CONNTRACK_MARK=y
# CONFIG_IP_NF_CT_PROTO_SCTP is not set
# CONFIG_IP_NF_FTP is not set
# CONFIG_IP_NF_IRC is not set
# CONFIG_IP_NF_TFTP is not set
# CONFIG_IP_NF_AMANDA is not set
# CONFIG_IP_NF_QUEUE is not set
CONFIG_IP_NF_IPTABLES=y
# CONFIG_IP_NF_MATCH_LIMIT is not set
# CONFIG_IP_NF_MATCH_IPRANGE is not set
# CONFIG_IP_NF_MATCH_MAC is not set
CONFIG_IP_NF_MATCH_PKTTYPE=y
CONFIG_IP_NF_MATCH_MARK=y
CONFIG_IP_NF_MATCH_MULTIPORT=y
# CONFIG_IP_NF_MATCH_TOS is not set
# CONFIG_IP_NF_MATCH_RECENT is not set
# CONFIG_IP_NF_MATCH_ECN is not set
# CONFIG_IP_NF_MATCH_DSCP is not set
CONFIG_IP_NF_MATCH_AH_ESP=y
# CONFIG_IP_NF_MATCH_LENGTH is not set
CONFIG_IP_NF_MATCH_TTL=y
# CONFIG_IP_NF_MATCH_TCPMSS is not set
# CONFIG_IP_NF_MATCH_HELPER is not set
CONFIG_IP_NF_MATCH_STATE=y
# CONFIG_IP_NF_MATCH_CONNTRACK is not set
# CONFIG_IP_NF_MATCH_OWNER is not set
# CONFIG_IP_NF_MATCH_ADDRTYPE is not set
# CONFIG_IP_NF_MATCH_REALM is not set
# CONFIG_IP_NF_MATCH_SCTP is not set
# CONFIG_IP_NF_MATCH_COMMENT is not set
CONFIG_IP_NF_MATCH_CONNMARK=y
# CONFIG_IP_NF_MATCH_HASHLIMIT is not set
CONFIG_IP_NF_FILTER=y
# CONFIG_IP_NF_TARGET_REJECT is not set
CONFIG_IP_NF_TARGET_LOG=y
# CONFIG_IP_NF_TARGET_ULOG is not set
# CONFIG_IP_NF_TARGET_TCPMSS is not set
CONFIG_IP_NF_NAT=y
CONFIG_IP_NF_NAT_NEEDED=y
CONFIG_IP_NF_TARGET_MASQUERADE=y
# CONFIG_IP_NF_TARGET_REDIRECT is not set
# CONFIG_IP_NF_TARGET_NETMAP is not set
# CONFIG_IP_NF_TARGET_SAME is not set
# CONFIG_IP_NF_NAT_LOCAL is not set
# CONFIG_IP_NF_NAT_SNMP_BASIC is not set
CONFIG_IP_NF_MANGLE=y
# CONFIG_IP_NF_TARGET_TOS is not set
# CONFIG_IP_NF_TARGET_ECN is not set
# CONFIG_IP_NF_TARGET_DSCP is not set
CONFIG_IP_NF_TARGET_MARK=y
# CONFIG_IP_NF_TARGET_CLASSIFY is not set
CONFIG_IP_NF_TARGET_CONNMARK=y
# CONFIG_IP_NF_TARGET_CLUSTERIP is not set
# CONFIG_IP_NF_RAW is not set
# CONFIG_IP_NF_ARPTABLES is not set
CONFIG_XFRM=y
CONFIG_XFRM_USER=y
 
#
# SCTP Configuration (EXPERIMENTAL)
#
# CONFIG_IP_SCTP is not set
# CONFIG_ATM is not set
# CONFIG_BRIDGE is not set
# CONFIG_VLAN_8021Q is not set
# CONFIG_DECNET is not set
# CONFIG_LLC2 is not set
# CONFIG_IPX is not set
# CONFIG_ATALK is not set
# CONFIG_X25 is not set
# CONFIG_LAPB is not set
# CONFIG_NET_DIVERT is not set
# CONFIG_ECONET is not set
# CONFIG_WAN_ROUTER is not set
 
#
# QoS and/or fair queueing
#
# CONFIG_NET_SCHED is not set
# CONFIG_NET_CLS_ROUTE is not set
 
#
# Network testing
#
# CONFIG_NET_PKTGEN is not set
# CONFIG_NETPOLL is not set
# CONFIG_NET_POLL_CONTROLLER is not set
# CONFIG_HAMRADIO is not set
# CONFIG_IRDA is not set
# CONFIG_BT is not set
CONFIG_DUMMY=y
# CONFIG_BONDING is not set
# CONFIG_EQUALIZER is not set
CONFIG_TUN=y
 
#
# Ethernet (10 or 100Mbit)
#
CONFIG_NET_ETHERNET=y
# CONFIG_MII is not set
 
#
# Ethernet (1000 Mbit)
#
 
#
# Ethernet (10000 Mbit)
#
 
#
# Token Ring devices
#
 
#
# Wireless LAN (non-hamradio)
#
# CONFIG_NET_RADIO is not set
 
#
# Wan interfaces
#
# CONFIG_WAN is not set
CONFIG_PPP=y
# CONFIG_PPP_MULTILINK is not set
# CONFIG_PPP_FILTER is not set
# CONFIG_PPP_ASYNC is not set
# CONFIG_PPP_SYNC_TTY is not set
# CONFIG_PPP_DEFLATE is not set
# CONFIG_PPP_BSDCOMP is not set
# CONFIG_PPPOE is not set
CONFIG_SLIP=y
# CONFIG_SLIP_COMPRESSED is not set
# CONFIG_SLIP_SMART is not set
# CONFIG_SLIP_MODE_SLIP6 is not set
# CONFIG_SHAPER is not set
# CONFIG_NETCONSOLE is not set
 
#
# File systems
#
CONFIG_EXT2_FS=y
# CONFIG_EXT2_FS_XATTR is not set
# CONFIG_EXT3_FS is not set
# CONFIG_JBD is not set
CONFIG_REISERFS_FS=y
# CONFIG_REISERFS_CHECK is not set
# CONFIG_REISERFS_PROC_INFO is not set
# CONFIG_REISERFS_FS_XATTR is not set
# CONFIG_JFS_FS is not set
# CONFIG_XFS_FS is not set
CONFIG_MINIX_FS=y
# CONFIG_ROMFS_FS is not set
CONFIG_QUOTA=y
# CONFIG_QFMT_V1 is not set
# CONFIG_QFMT_V2 is not set
CONFIG_QUOTACTL=y
CONFIG_DNOTIFY=y
CONFIG_AUTOFS_FS=y
CONFIG_AUTOFS4_FS=y
 
#
# CD-ROM/DVD Filesystems
#
CONFIG_ISO9660_FS=y
# CONFIG_JOLIET is not set
# CONFIG_ZISOFS is not set
# CONFIG_UDF_FS is not set
 
#
# DOS/FAT/NT Filesystems
#
CONFIG_FAT_FS=y
CONFIG_MSDOS_FS=y
CONFIG_VFAT_FS=y
CONFIG_FAT_DEFAULT_CODEPAGE=437
CONFIG_FAT_DEFAULT_IOCHARSET="iso8859-1"
# CONFIG_NTFS_FS is not set
 
#
# Pseudo filesystems
#
CONFIG_PROC_FS=y
CONFIG_PROC_KCORE=y
CONFIG_SYSFS=y
CONFIG_DEVFS_FS=y
# CONFIG_DEVFS_MOUNT is not set
# CONFIG_DEVFS_DEBUG is not set
# CONFIG_DEVPTS_FS_XATTR is not set
CONFIG_TMPFS=y
# CONFIG_TMPFS_XATTR is not set
# CONFIG_HUGETLB_PAGE is not set
CONFIG_RAMFS=y
 
#
# Miscellaneous filesystems
#
# CONFIG_ADFS_FS is not set
# CONFIG_AFFS_FS is not set
# CONFIG_HFS_FS is not set
# CONFIG_HFSPLUS_FS is not set
# CONFIG_BEFS_FS is not set
# CONFIG_BFS_FS is not set
# CONFIG_EFS_FS is not set
# CONFIG_CRAMFS is not set
# CONFIG_VXFS_FS is not set
# CONFIG_HPFS_FS is not set
# CONFIG_QNX4FS_FS is not set
# CONFIG_SYSV_FS is not set
# CONFIG_UFS_FS is not set
 
#
# Network File Systems
#
# CONFIG_NFS_FS is not set
# CONFIG_NFSD is not set
# CONFIG_EXPORTFS is not set
# CONFIG_SMB_FS is not set
# CONFIG_CIFS is not set
# CONFIG_NCP_FS is not set
# CONFIG_CODA_FS is not set
# CONFIG_AFS_FS is not set
 
#
# Partition Types
#
# CONFIG_PARTITION_ADVANCED is not set
CONFIG_MSDOS_PARTITION=y
 
#
# Native Language Support
#
CONFIG_NLS=y
CONFIG_NLS_DEFAULT="iso8859-1"
# CONFIG_NLS_CODEPAGE_437 is not set
# CONFIG_NLS_CODEPAGE_737 is not set
# CONFIG_NLS_CODEPAGE_775 is not set
# CONFIG_NLS_CODEPAGE_850 is not set
# CONFIG_NLS_CODEPAGE_852 is not set
# CONFIG_NLS_CODEPAGE_855 is not set
# CONFIG_NLS_CODEPAGE_857 is not set
# CONFIG_NLS_CODEPAGE_860 is not set
# CONFIG_NLS_CODEPAGE_861 is not set
# CONFIG_NLS_CODEPAGE_862 is not set
# CONFIG_NLS_CODEPAGE_863 is not set
# CONFIG_NLS_CODEPAGE_864 is not set
# CONFIG_NLS_CODEPAGE_865 is not set
# CONFIG_NLS_CODEPAGE_866 is not set
# CONFIG_NLS_CODEPAGE_869 is not set
# CONFIG_NLS_CODEPAGE_936 is not set
# CONFIG_NLS_CODEPAGE_950 is not set
# CONFIG_NLS_CODEPAGE_932 is not set
# CONFIG_NLS_CODEPAGE_949 is not set
# CONFIG_NLS_CODEPAGE_874 is not set
# CONFIG_NLS_ISO8859_8 is not set
# CONFIG_NLS_CODEPAGE_1250 is not set
# CONFIG_NLS_CODEPAGE_1251 is not set
# CONFIG_NLS_ASCII is not set
# CONFIG_NLS_ISO8859_1 is not set
# CONFIG_NLS_ISO8859_2 is not set
# CONFIG_NLS_ISO8859_3 is not set
# CONFIG_NLS_ISO8859_4 is not set
# CONFIG_NLS_ISO8859_5 is not set
# CONFIG_NLS_ISO8859_6 is not set
# CONFIG_NLS_ISO8859_7 is not set
# CONFIG_NLS_ISO8859_9 is not set
# CONFIG_NLS_ISO8859_13 is not set
# CONFIG_NLS_ISO8859_14 is not set
# CONFIG_NLS_ISO8859_15 is not set
# CONFIG_NLS_KOI8_R is not set
# CONFIG_NLS_KOI8_U is not set
# CONFIG_NLS_UTF8 is not set
 
#
# Security options
#
# CONFIG_KEYS is not set
# CONFIG_SECURITY is not set
 
#
# Cryptographic options
#
CONFIG_CRYPTO=y
CONFIG_CRYPTO_HMAC=y
CONFIG_CRYPTO_NULL=y
# CONFIG_CRYPTO_MD4 is not set
CONFIG_CRYPTO_MD5=y
CONFIG_CRYPTO_SHA1=y
CONFIG_CRYPTO_SHA256=y
CONFIG_CRYPTO_SHA512=y
# CONFIG_CRYPTO_WP512 is not set
CONFIG_CRYPTO_DES=y
CONFIG_CRYPTO_BLOWFISH=y
CONFIG_CRYPTO_TWOFISH=y
CONFIG_CRYPTO_SERPENT=y
CONFIG_CRYPTO_AES=y
# CONFIG_CRYPTO_CAST5 is not set
# CONFIG_CRYPTO_CAST6 is not set
# CONFIG_CRYPTO_TEA is not set
# CONFIG_CRYPTO_ARC4 is not set
# CONFIG_CRYPTO_KHAZAD is not set
# CONFIG_CRYPTO_ANUBIS is not set
CONFIG_CRYPTO_DEFLATE=y
# CONFIG_CRYPTO_MICHAEL_MIC is not set
# CONFIG_CRYPTO_CRC32C is not set
# CONFIG_CRYPTO_TEST is not set
 
#
# Library routines
#
# CONFIG_CRC_CCITT is not set
# CONFIG_CRC32 is not set
# CONFIG_LIBCRC32C is not set
CONFIG_ZLIB_INFLATE=y
CONFIG_ZLIB_DEFLATE=y
 
#
# Multi-device support (RAID and LVM)
#
# CONFIG_MD is not set
# CONFIG_INPUT is not set
 
#
# Kernel hacking
#
# CONFIG_DEBUG_KERNEL is not set
          
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Fax: (86)10-6265-7255
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National Research Centre for High Performance Computer
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