UML doesn't compile in 2.6.21

UML doesn't compile in 2.6.21

[Robert Schwebel]

Jeff,

Any idea how this could happen? I'm trying to build 2.6.21 for ARCH=um, and the
linker stage explodes here:

  CHK     include/linux/compile.h
  UPD     include/linux/compile.h
  CC      init/version.o
  LD      init/built-in.o
  LD      .tmp_vmlinux1
lib/lib.a(bug.o): In function `find_bug':
bug.c:(.text+0x171): undefined reference to `__start___bug_table'
bug.c:(.text+0x177): undefined reference to `__stop___bug_table'
bug.c:(.text+0x180): undefined reference to `__start___bug_table'
bug.c:(.text+0x193): undefined reference to `__stop___bug_table'
collect2: ld returned 1 exit status
  KSYM    .tmp_kallsyms1.S
nm: '.tmp_vmlinux1': No such file
No valid symbol.
make[1]: *** [.tmp_kallsyms1.S] Error 1

Robert
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
     Hannoversche Str. 2, 31134 Hildesheim, Germany
   Phone: +49-5121-206917-0 |  Fax: +49-5121-206917-9

Re: UML doesn't compile in 2.6.21

[Rob Landley]

On Wednesday 16 May 2007 6:49 pm, Robert Schwebel wrote:
> Jeff,
> 
> Any idea how this could happen? I'm trying to build 2.6.21 for ARCH=um, and 
the
> linker stage explodes here:

2.6.21.1 built for me:

tar xvjf linux-2.6.21.1.tar.bz2 &&
cd linux-2.6.21.1 &&
cat > mini.conf << EOF
CONFIG_MODE_SKAS=y
CONFIG_BINFMT_ELF=y
CONFIG_HOSTFS=y
CONFIG_SYSCTL=y
CONFIG_STDERR_CONSOLE=y
CONFIG_UNIX98_PTYS=y
CONFIG_BLK_DEV_LOOP=y
CONFIG_LBD=y
CONFIG_EXT2_FS=y
CONFIG_PROC_FS=y
EOF
make ARCH=um allnoconfig KCONFIG_ALLCONFIG=mini.conf &&
make ARCH=um &&
./linux rootfstype=hostfs rw init=/bin/sh

Does this not work for you?

Rob

Re: UML doesn't compile in 2.6.21

[Robert Schwebel]

Rob,

On Wed, May 16, 2007 at 09:11:18PM -0400, Rob Landley wrote:
> 2.6.21.1 built for me:
> 
> tar xvjf linux-2.6.21.1.tar.bz2 &&
> cd linux-2.6.21.1 &&
> cat > mini.conf << EOF
> CONFIG_MODE_SKAS=y
> CONFIG_BINFMT_ELF=y
> CONFIG_HOSTFS=y
> CONFIG_SYSCTL=y
> CONFIG_STDERR_CONSOLE=y
> CONFIG_UNIX98_PTYS=y
> CONFIG_BLK_DEV_LOOP=y
> CONFIG_LBD=y
> CONFIG_EXT2_FS=y
> CONFIG_PROC_FS=y
> EOF
> make ARCH=um allnoconfig KCONFIG_ALLCONFIG=mini.conf &&
> make ARCH=um &&
> ./linux rootfstype=hostfs rw init=/bin/sh
> 
> Does this not work for you?

Yes, this compiles - with this warning, btw:

WARNING: vmlinux - Section mismatch: reference to .init.text:lpj_setup from .got after '_GLOBAL_OFFSET_TABLE_' (at offset 0x814de34)
WARNING: vmlinux - Section mismatch: reference to .init.text:set_reset_devices from .bss between 'stdout@@GLIBC_2.0' (at offset 0x814de40) and 'stderr@@GLIBC_2.0'

So it must be something with my configuration. I've tried to build a
minimized configuration, see below. You can trigger the bug here by
changing "Enable loadable module support.

Robert
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
     Hannoversche Str. 2, 31134 Hildesheim, Germany
   Phone: +49-5121-206917-0 |  Fax: +49-5121-206917-9

#
# Automatically generated make config: don't edit
# Linux kernel version: 2.6.21
# Thu May 17 23:01:31 2007
#
CONFIG_DEFCONFIG_LIST="arch/$ARCH/defconfig"
CONFIG_GENERIC_HARDIRQS=y
CONFIG_UML=y
CONFIG_MMU=y
CONFIG_NO_IOMEM=y
# CONFIG_TRACE_IRQFLAGS_SUPPORT is not set
CONFIG_LOCKDEP_SUPPORT=y
# CONFIG_STACKTRACE_SUPPORT is not set
CONFIG_GENERIC_CALIBRATE_DELAY=y
CONFIG_GENERIC_BUG=y
CONFIG_IRQ_RELEASE_METHOD=y

#
# UML-specific options
#
# CONFIG_STATIC_LINK is not set
CONFIG_MODE_SKAS=y

#
# Host processor type and features
#
# CONFIG_M386 is not set
# CONFIG_M486 is not set
# CONFIG_M586 is not set
# CONFIG_M586TSC is not set
# CONFIG_M586MMX is not set
CONFIG_M686=y
# CONFIG_MPENTIUMII is not set
# CONFIG_MPENTIUMIII is not set
# CONFIG_MPENTIUMM is not set
# CONFIG_MCORE2 is not set
# CONFIG_MPENTIUM4 is not set
# CONFIG_MK6 is not set
# CONFIG_MK7 is not set
# CONFIG_MK8 is not set
# CONFIG_MCRUSOE is not set
# CONFIG_MEFFICEON is not set
# CONFIG_MWINCHIPC6 is not set
# CONFIG_MWINCHIP2 is not set
# CONFIG_MWINCHIP3D is not set
# CONFIG_MGEODEGX1 is not set
# CONFIG_MGEODE_LX is not set
# CONFIG_MCYRIXIII is not set
# CONFIG_MVIAC3_2 is not set
# CONFIG_X86_GENERIC is not set
CONFIG_X86_CMPXCHG=y
CONFIG_X86_L1_CACHE_SHIFT=5
CONFIG_RWSEM_XCHGADD_ALGORITHM=y
# CONFIG_ARCH_HAS_ILOG2_U32 is not set
# CONFIG_ARCH_HAS_ILOG2_U64 is not set
CONFIG_X86_PPRO_FENCE=y
CONFIG_X86_WP_WORKS_OK=y
CONFIG_X86_INVLPG=y
CONFIG_X86_BSWAP=y
CONFIG_X86_POPAD_OK=y
CONFIG_X86_CMPXCHG64=y
CONFIG_X86_GOOD_APIC=y
CONFIG_X86_USE_PPRO_CHECKSUM=y
CONFIG_X86_TSC=y
CONFIG_UML_X86=y
# CONFIG_64BIT is not set
CONFIG_SEMAPHORE_SLEEPERS=y
CONFIG_HOST_VMSPLIT_3G=y
# CONFIG_HOST_VMSPLIT_3G_OPT is not set
# CONFIG_HOST_VMSPLIT_2G is not set
# CONFIG_HOST_VMSPLIT_1G is not set
CONFIG_TOP_ADDR=0xC0000000
# CONFIG_3_LEVEL_PGTABLES is not set
CONFIG_STUB_CODE=0xbfffe000
CONFIG_STUB_DATA=0xbffff000
CONFIG_STUB_START=0xbfffe000
CONFIG_ARCH_HAS_SC_SIGNALS=y
CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA=y
CONFIG_GENERIC_HWEIGHT=y
CONFIG_SELECT_MEMORY_MODEL=y
CONFIG_FLATMEM_MANUAL=y
# CONFIG_DISCONTIGMEM_MANUAL is not set
# CONFIG_SPARSEMEM_MANUAL is not set
CONFIG_FLATMEM=y
CONFIG_FLAT_NODE_MEM_MAP=y
# CONFIG_SPARSEMEM_STATIC is not set
CONFIG_SPLIT_PTLOCK_CPUS=4
# CONFIG_RESOURCES_64BIT is not set
CONFIG_ZONE_DMA_FLAG=0
CONFIG_LD_SCRIPT_DYN=y
# CONFIG_NET is not set
CONFIG_BINFMT_ELF=y
CONFIG_BINFMT_MISC=y
CONFIG_HOSTFS=y
# CONFIG_HPPFS is not set
CONFIG_MCONSOLE=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_NEST_LEVEL=0
CONFIG_HIGHMEM=y
CONFIG_KERNEL_STACK_ORDER=2
CONFIG_UML_REAL_TIME_CLOCK=y

#
# Code maturity level options
#
CONFIG_EXPERIMENTAL=y
CONFIG_BROKEN_ON_SMP=y
CONFIG_INIT_ENV_ARG_LIMIT=128

#
# General setup
#
CONFIG_LOCALVERSION=""
CONFIG_LOCALVERSION_AUTO=y
CONFIG_SYSVIPC=y
# CONFIG_IPC_NS is not set
CONFIG_SYSVIPC_SYSCTL=y
CONFIG_BSD_PROCESS_ACCT=y
# CONFIG_BSD_PROCESS_ACCT_V3 is not set
# CONFIG_UTS_NS is not set
# CONFIG_IKCONFIG is not set
CONFIG_SYSFS_DEPRECATED=y
# CONFIG_RELAY is not set
# CONFIG_BLK_DEV_INITRD is not set
# CONFIG_CC_OPTIMIZE_FOR_SIZE is not set
CONFIG_SYSCTL=y
CONFIG_EMBEDDED=y
CONFIG_UID16=y
CONFIG_SYSCTL_SYSCALL=y
CONFIG_KALLSYMS=y
# CONFIG_KALLSYMS_EXTRA_PASS is not set
CONFIG_HOTPLUG=y
CONFIG_PRINTK=y
CONFIG_BUG=y
CONFIG_ELF_CORE=y
CONFIG_BASE_FULL=y
CONFIG_FUTEX=y
CONFIG_EPOLL=y
CONFIG_SHMEM=y
CONFIG_SLAB=y
CONFIG_VM_EVENT_COUNTERS=y
CONFIG_RT_MUTEXES=y
# CONFIG_TINY_SHMEM is not set
CONFIG_BASE_SMALL=0
# CONFIG_SLOB is not set

#
# Loadable module support
#
CONFIG_MODULES=y
# CONFIG_MODULE_UNLOAD is not set
# CONFIG_MODVERSIONS is not set
# CONFIG_MODULE_SRCVERSION_ALL is not set
# CONFIG_KMOD is not set

#
# Block layer
#
# CONFIG_BLOCK is not set
# CONFIG_MMAPPER is not set

#
# Character Devices
#
# CONFIG_STDERR_CONSOLE is not set
CONFIG_STDIO_CONSOLE=y
# CONFIG_SSL is not set
# CONFIG_NULL_CHAN is not set
# CONFIG_PORT_CHAN is not set
# CONFIG_PTY_CHAN is not set
# CONFIG_TTY_CHAN is not set
# CONFIG_XTERM_CHAN is not set
CONFIG_NOCONFIG_CHAN=y
CONFIG_CON_ZERO_CHAN="fd:0,fd:1"
CONFIG_CON_CHAN="port"
CONFIG_SSL_CHAN="port"
# CONFIG_UNIX98_PTYS is not set
# CONFIG_LEGACY_PTYS is not set
# CONFIG_RAW_DRIVER is not set
# CONFIG_WATCHDOG is not set
# CONFIG_UML_SOUND is not set
# CONFIG_SOUND is not set
# CONFIG_HOSTAUDIO is not set
# CONFIG_HW_RANDOM is not set
# CONFIG_UML_RANDOM is not set

#
# Generic Driver Options
#
# CONFIG_STANDALONE is not set
# CONFIG_PREVENT_FIRMWARE_BUILD is not set
# CONFIG_FW_LOADER is not set
# CONFIG_SYS_HYPERVISOR is not set

#
# Networking
#

#
# Connector - unified userspace <-> kernelspace linker
#

#
# File systems
#
# CONFIG_INOTIFY is not set
# CONFIG_QUOTA is not set
# CONFIG_DNOTIFY is not set
# CONFIG_AUTOFS_FS is not set
# CONFIG_AUTOFS4_FS is not set
# CONFIG_FUSE_FS is not set

#
# Pseudo filesystems
#
# CONFIG_PROC_FS is not set
# CONFIG_SYSFS is not set
# CONFIG_TMPFS is not set
# CONFIG_HUGETLB_PAGE is not set
CONFIG_RAMFS=y

#
# Miscellaneous filesystems
#

#
# Native Language Support
#
# CONFIG_NLS is not set

#
# Security options
#
# CONFIG_KEYS is not set

#
# Cryptographic options
#
# CONFIG_CRYPTO is not set

#
# Library routines
#
# CONFIG_CRC_CCITT is not set
# CONFIG_CRC16 is not set
# CONFIG_CRC32 is not set
# CONFIG_LIBCRC32C is not set
CONFIG_PLIST=y
# CONFIG_INPUT is not set

#
# Kernel hacking
#
# CONFIG_PRINTK_TIME is not set
# CONFIG_ENABLE_MUST_CHECK is not set
# CONFIG_UNUSED_SYMBOLS is not set
# CONFIG_DEBUG_KERNEL is not set
CONFIG_LOG_BUF_SHIFT=14
# CONFIG_DEBUG_BUGVERBOSE is not set

Re: UML doesn't compile in 2.6.21

[Robert Schwebel]

On Thu, May 17, 2007 at 11:05:38PM +0200, Robert Schwebel wrote:
> So it must be something with my configuration. I've tried to build a
> minimized configuration, see below. You can trigger the bug here by
> changing "Enable loadable module support.

update: it can also be triggered by switching off the "embedded" option.

Robert 
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
     Hannoversche Str. 2, 31134 Hildesheim, Germany
   Phone: +49-5121-206917-0 |  Fax: +49-5121-206917-9

Re: UML doesn't compile in 2.6.21

[Rob Landley]

[-- Attachment #1: Type: text/plain, Size: 2176 bytes --]

On Thursday 17 May 2007 5:05 pm, Robert Schwebel wrote:
> Rob,
> 
> On Wed, May 16, 2007 at 09:11:18PM -0400, Rob Landley wrote:
> > 2.6.21.1 built for me:
> > 
> > tar xvjf linux-2.6.21.1.tar.bz2 &&
> > cd linux-2.6.21.1 &&
> > cat > mini.conf << EOF
> > CONFIG_MODE_SKAS=y
> > CONFIG_BINFMT_ELF=y
> > CONFIG_HOSTFS=y
> > CONFIG_SYSCTL=y
> > CONFIG_STDERR_CONSOLE=y
> > CONFIG_UNIX98_PTYS=y
> > CONFIG_BLK_DEV_LOOP=y
> > CONFIG_LBD=y
> > CONFIG_EXT2_FS=y
> > CONFIG_PROC_FS=y
> > EOF
> > make ARCH=um allnoconfig KCONFIG_ALLCONFIG=mini.conf &&
> > make ARCH=um &&
> > ./linux rootfstype=hostfs rw init=/bin/sh
> > 
> > Does this not work for you?
> 
> Yes, this compiles - with this warning, btw:
> 
> WARNING: vmlinux - Section mismatch: reference to .init.text:lpj_setup 
from .got after '_GLOBAL_OFFSET_TABLE_' (at offset 0x814de34)
> WARNING: vmlinux - Section mismatch: reference 
to .init.text:set_reset_devices from .bss between 'stdout@@GLIBC_2.0' (at 
offset 0x814de40) and 'stderr@@GLIBC_2.0'
> 
> So it must be something with my configuration. I've tried to build a
> minimized configuration, see below.

You can either make a minimized configuration by hand, or you can use my 
shrinker script (which is slow, but can be left running in a background 
window).  I've attached the script.

For ARCH=um, you'd cd to your linux source directory that has the .config you 
want, and run it like:

  ARCH=um ./miniconfig.sh mini.conf

And it should produce a file "mini.conf" when it's done.  The progress 
indicator shows two numbers (111/222) which are the number of lines it's 
confirmed it needs to keep, and the total number of lines remaining in the 
file.  The one of the left counts up, the one on the right counts down, when 
they match, it's done.

Doing a better version of this in C as a patch to the kconfig infrastructure 
has been a todo item of mine for over two years. :(

> You can trigger the bug here by 
> changing "Enable loadable module support.

UML supports modules?  Huh.  (Yeah, I suppose it does.  I've never used it.)

So the bug is "module support doesn't compile in UML 2.6.21" then.  Might want 
to change the title and resubmit. :)

Rob

[-- Attachment #2: miniconfig.sh --]
[-- Type: application/x-shellscript, Size: 1425 bytes --]

Re: UML doesn't compile in 2.6.21

[Jeff Dike]

On Thu, May 17, 2007 at 12:49:38AM +0200, Robert Schwebel wrote:
> Jeff,
> 
> Any idea how this could happen? I'm trying to build 2.6.21 for
> ARCH=um, and the linker stage explodes here:
> 
>   CHK     include/linux/compile.h
>   UPD     include/linux/compile.h
>   CC      init/version.o
>   LD      init/built-in.o
>   LD      .tmp_vmlinux1
> lib/lib.a(bug.o): In function `find_bug':
> bug.c:(.text+0x171): undefined reference to `__start___bug_table'
> bug.c:(.text+0x177): undefined reference to `__stop___bug_table'
> bug.c:(.text+0x180): undefined reference to `__start___bug_table'
> bug.c:(.text+0x193): undefined reference to `__stop___bug_table'

No, I don't.  The bug_table symbols are rather unconditionally defined
in asm-generic/vmlinux.lds.h.  This can't be affected by any config
settings that I can see, let alone module support.  Further, the
config I always build has modules enabled, and I've never seen this.

Can you try starting over with an mrproper and see if you can
reproduce it?

				Jeff

-- 
Work email - jdike at linux dot intel dot com