On 14/03/2016 21:47, Gordan Bobic wrote:
> On 2016-03-14 21:41, Michael Howard wrote:
>> On 14/03/2016 17:16, Gordan Bobic wrote:
>>> On 2016-03-14 17:13, Michael Howard wrote:
>>>> On 14/03/2016 16:56, Gordan Bobic wrote:
>>>>> On 2016-03-14 15:00, Gordan Bobic wrote:
>>>>>> On 2016-03-01 22:32, Michael Howard wrote:
>>>>>>> On 01/03/2016 22:26, Richard W.M. Jones wrote:
>>>>>>>> On Mon, Feb 29, 2016 at 03:20:03PM +0000, Michael Howard wrote:
>>>>>>>>> Just to let you know, I can't get this to work. aarch64 is
>>>>>>>>> supposed
>>>>>>>>> to be binary compatible, with the correct libraries installed,
>>>>>>>>> but
>>>>>>>>> I'm thinking the cpu isn't.
>>>>>>>>>
>>>>>>>>> All I get is 'cannot execute binary file: Exec format error',
>>>>>>>>> regardless of what I try.
>>>>>>>> As I understand it the problem is page size - 64K was chosen by
>>>>>>>> Red Hat for aarch64, where as 4K is the norm on armv7.
>>>>>>>>
>>>>>>>> Anyway, you can run a 32 bit VM and it works well -- in fact a lot
>>>>>>>> faster than regular 32 bit armv7 hardware.
>>>>>>>>
>>>>>>>
>>>>>>> Yes, with CONFIG_ARM64_4K_PAGES=y and CONFIG_COMPAT=y, 32 bit
>>>>>>> binaries run fine.
>>>>>>
>>>>>> I built a kernel with these options enabled, but chrooting into an
>>>>>> armv5tel subtree segfaults immediately. :-(
>>>>>>
>>>>>> # grep -E "CONFIG_COMPAT=|CONFIG_ARM64_4K_PAGES=" /boot/config-4.4.5
>>>>>> CONFIG_ARM64_4K_PAGES=y
>>>>>> CONFIG_COMPAT=y
>>>>>>
>>>>>> # chroot /orcone/docker/rsel6/
>>>>>> Segmentation fault
>>>>>>
>>>>>> The chroot is armv5tel soft-float, which I think should work.
>>>>>> Oddly, I see no mention of a segfault in dmesg or in
>>>>>> /var/log/messages
>>>>>> on the host...
>>>>>>
>>>>>> # strace chroot /orcone/docker/media/
>>>>>> execve("/sbin/chroot", ["chroot", "/orcone/docker/media/"], [/*
>>>>>> 18 vars */]) = 0
>>>>>> brk(0) = 0x153eb000
>>>>>> mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
>>>>>> -1,
>>>>>> 0) = 0x7f98108000
>>>>>> faccessat(AT_FDCWD, "/etc/ld.so.preload", R_OK) = -1 ENOENT (No such
>>>>>> file or directory)
>>>>>> openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
>>>>>> fstat(3, {st_mode=S_IFREG|0644, st_size=23876, ...}) = 0
>>>>>> mmap(NULL, 23876, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f98102000
>>>>>> close(3) = 0
>>>>>> openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
>>>>>> read(3,
>>>>>> "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0\267\0\1\0\0\0\270\r\2\0\0\0\0\0"...,
>>>>>> 832) = 832
>>>>>> fstat(3, {st_mode=S_IFREG|0755, st_size=1801536, ...}) = 0
>>>>>> mmap(NULL, 1528796, PROT_READ|PROT_EXEC,
>>>>>> MAP_PRIVATE|MAP_DENYWRITE, 3,
>>>>>> 0) = 0x7f97f66000
>>>>>> mprotect(0x7f980c2000, 65536, PROT_NONE) = 0
>>>>>> mmap(0x7f980d2000, 24576, PROT_READ|PROT_WRITE,
>>>>>> MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x15c000) = 0x7f980d2000
>>>>>> mmap(0x7f980d8000, 13276, PROT_READ|PROT_WRITE,
>>>>>> MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f980d8000
>>>>>> close(3) = 0
>>>>>> mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
>>>>>> -1,
>>>>>> 0) = 0x7f98101000
>>>>>> mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
>>>>>> -1,
>>>>>> 0) = 0x7f98100000
>>>>>> mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
>>>>>> -1,
>>>>>> 0) = 0x7f980ff000
>>>>>> mprotect(0x7f980d2000, 16384, PROT_READ) = 0
>>>>>> mprotect(0x41f000, 4096, PROT_READ) = 0
>>>>>> mprotect(0x7f9810b000, 4096, PROT_READ) = 0
>>>>>> munmap(0x7f98102000, 23876) = 0
>>>>>> brk(0) = 0x153eb000
>>>>>> brk(0x1540c000) = 0x1540c000
>>>>>> brk(0) = 0x1540c000
>>>>>> openat(AT_FDCWD, "/usr/lib/locale/locale-archive",
>>>>>> O_RDONLY|O_CLOEXEC) = 3
>>>>>> fstat(3, {st_mode=S_IFREG|0644, st_size=109669264, ...}) = 0
>>>>>> mmap(NULL, 109669264, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f916cf000
>>>>>> close(3) = 0
>>>>>> chroot("/orcone/docker/media/") = 0
>>>>>> chdir("/") = 0
>>>>>> execve("/bin/bash", ["/bin/bash", "-i"], [/* 18 vars */]) =
>>>>>> -1053305918634065933
>>>>>> --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
>>>>>> +++ killed by SIGSEGV +++
>>>>>> Segmentation fault
>>>>>>
>>>>>>
>>>>>> What am I doing differently?
>>>>>
>>>>> Just to make sure we are as much on the same page as possible, here
>>>>> is the minimal chroot I am trying:
>>>>> http://ftp.redsleeve.org/pub/el6-staging/rootfs/rsel6-minimal.tar.xz
>>>>>
>>>>> Built from the latest RedSleeve 6 binaries using:
>>>>> yum --installroot=/some/path install @core
>>>>>
>>>>> Can you extract that into an empty folder and chroot into it
>>>>> from your aarch64 CentOS 7 install? Does it work for you or
>>>>> does it segfault?
>>>>>
>>>>> If it works for you, any chance you could post your kernel
>>>>> config somewhere? It's the only thing I can think of that
>>>>> could plausibly be causeing the discrepancy (I am on 4.4.5
>>>>> and IIRC you were on 4.5rc).
>>>>
>>>> Downloading now but it will be a couple of hours before I can check
>>>> it out.
>>>
>>> Thanks, most appreciated. You may want to re-download, as I literally
>>> just replaced with tar ball with a more compressed version. If that
>>> happened
>>> during your download, what you get may end up being corrupted (check
>>> whether
>>> it matches the md5 checksum).
>>
>> I did re-download, just in case. It all works here as expected.
>>
>> [root at mp30 ~]# chroot ~/CHROOT2
>> [root at mp30 ~]# echo "nameserver 192.168.1.2" > /etc/resolv.conf
>> [root at mp30 /]# yum search linux
>> base | 3.8 kB
>> 00:00
>> updates | 3.0 kB
>> 00:00
>> ============================== N/S Matched: linux
>> ==============================
>> libselinux.armv5tel : SELinux library and simple utilities
>> libselinux-utils.armv5tel : SELinux libselinux utilies
>> python-linux-procfs.noarch : Linux /proc abstraction classes
>> selinux-policy.noarch : SELinux policy configuration
>> selinux-policy-doc.noarch : SELinux policy documentation
>> selinux-policy-minimum.noarch : SELinux minimum base policy
>> selinux-policy-mls.noarch : SELinux mls base policy
>> selinux- SELinux policy compiler
>> epel-release.noarch : Extra Packages for Enterprise Linux repository
>> : configuration
>> filesystem.armv5tel : The basic directory layout for a Linux system
>> iptables.armv5tel : Tools for managing Linux kernel packet filtering
>> : capabilities
>> libsemanage.armv5tel : SELinux binary policy manipulation library
>> libsepol.armv5tel : SELinux binary policy manipulation library
>> man-pages.noarch : Man (manual) pages from the Linux Documentation
>> Project
>> man-pages-cs.noarch : Czech man pages from the Linux Documentation
>> Project
>> man-pages-es.noarch : Spanish man pages from the Linux Documentation
>> Project
>> man-pages-fr.noarch : French version of the Linux man-pages
>> man-pages-it.noarch : Italian man (manual) pages from the Linux
>> Documentation
>> : Project
>> man-pages-pl.noarch : Polish man pages from the Linux Documentation
>> Project
>> man-pages-ru.noarch : Russian man pages from the Linux Documentation
>> Project
>> man-pages-uk.noarch : Ukrainian man pages from the Linux
>> Documentation Project
>> policycoreutils.armv5tel : SELinux policy core utilities
>> redhat-bookmarks.noarch : Red Hat Enterprise Linux bookmarks
>> redhat-indexhtml.noarch : Browser default start page for Red Hat
>> Enterprise
>> : Linux
>> redsleeve-release.armv5tel : Red Sleeve Enterprise Linux release file
>> rhel-guest-image-6.noarch : Red Hat Enterprise Linux Guest Images
>> util-linux-ng.armv5tel : A collection of basic system utilities
>>
>> Name and summary matches only, use "search all" for everything.
>> [root at mp30 /]# exit
>> [root at mp30 ~]#
>
> That is most puzzling. Any chance you could please post your kernel
> config file
> (pastebin it or similar)? I'd like to try to build one exactly the
> same and see
> if I can get it working.
No problem;
http://pastebin.com/4mrgmNGv
If all else fails (don't see why it should) I can put up the binary and
modules so you can triple check. I didn't build an RPM as I came across
a packaging problem, an aarch64/UTS_MACHINE issue I believe and I had no
idea how to solve it nor could I spend any real time investigating it.
--
Mike Howard