[Qemu-devel] PATCH: fix qemu-mips[el]-static to work with debian squeeze/sid chroot
I also recently tried to get a mipsel debian/sid chroot running under my amd64/squeeze system. As posted by Lisandro earlier this month, it didn't work. ;-) There are several problems, the most glaring of which the attached patch fixes. I'll break down the changes: 1. Return -TARGET_ENOSYS instead of -ENOSYS from linux-user/main.c * Caused the strange 'Level 2 synchronization messages' instead of correctly reporting the syscall was missing. * Made glibc simply fail instead of using older syscalls (one important example is the new setrlimit syscall which qemu lacks and gnupg/apt needs) 2. The mips syscall table wasn't kept in-sync with syscall.c * utimensat was missing (and the cause of the ENOSYS error Lisandro was seeing) * Although I didn't run into problems with any other syscalls, I updated the table to match syscall.c as well I could anyway 3. Dereferencing a null pointer causes an exception 0xC (EXCP_AdEL) instead of EXCP_TLBL. This should also trigger a segfault. 4. The codes for get/setrlimit do not stay constant between linux target platforms. I added a conversion method. This is important else programs (rsyslog, python, ...) can go into a near infinite loop trying to close all the file descriptors from 0 to -1. 5. 64-bit file system calls were failing on mipsel (ftruncate 888 created files 888*4GB large). arm had already work-around code for EABI which also worked for mipsel, so I just added the same code path for mips everywhere arm eabi has it. Works for both little and big endian. These changes were enough to get a mostly working debian chroot for me. I did have to install squeeze first and then dist-upgrade to sid, however, as debootstrap seems to have problems with the new multilib glibc (dist-upgrade will install it fine, though). To setup a mipsel chroot in /media with the patch applied: apt-get install qemu-user-static binfmt-support debootstrap debootstrap --foreign --arch=mipsel squeeze /media/mipsel-sid compile qemu with patch cp qemu-srcdir/mipsel-user-static /media/mipsel-sid/usr/bin chroot /media/mipsel-sid /debootstrap/debootstrap --second-stage echo deb http://ftp.de.debian.org/debian sid main /etc/apt/sources.list apt-get update apt-get install locales mount devpts /dev/pts -t devpts mount proc /proc -t proc mount sys /sys -t sysfs dpkg-reconfigure locales apt-get dist-upgrade ... install whatever else you need ... There is still some problem where gcc 4.6.1 in the chroot can ICE when handling floating point code. I'm looking into it. I would appreciate it if these fixes could be merged upstream. Thanks. * * qemu-mipsel-debian-rootfs.patch.gz Description: GNU Zip compressed data
Re: [Qemu-devel] PATCH: fix qemu-mips[el]-static to work with debian squeeze/sid chroot
On 5 July 2011 11:08, Wesley W. Terpstra terps...@debian.org wrote: I also recently tried to get a mipsel debian/sid chroot running under my amd64/squeeze system. As posted by Lisandro earlier this month, it didn't work. ;-) There are several problems, the most glaring of which the attached patch fixes. Thanks for this patch. To get it merged upstream it would be helpful if you could resubmit it in line with the guidelines at http://wiki.qemu.org/Contribute/SubmitAPatch (in particular it needs a Signed-off-by: line, it should be one patch per bug fix, and it needs to be against current head of qemu git). In the meantime, some minor initial review comments: @@ -1985,6 +1985,20 @@ MIPS_SYS(sys_epoll_pwait, 6) MIPS_SYS(sys_ioprio_set, 3) MIPS_SYS(sys_ioprio_get, 2) + MIPS_SYS(sys_utimensat, 4) + MIPS_SYS(sys_ni_syscall, 0) /* signalfd */ + MIPS_SYS(sys_ni_syscall, 0) /* timerfd */ + MIPS_SYS(sys_eventfd, 1) + MIPS_SYS(sys_fallocate, 4) + MIPS_SYS(sys_ni_syscall, 0) /* timerfd_create */ + MIPS_SYS(sys_ni_syscall, 0) /* timerfd_gettime */ + MIPS_SYS(sys_ni_syscall, 0) /* timerfd_settime */ + MIPS_SYS(sys_ni_syscall, 0) /* signalfd4 */ + MIPS_SYS(sys_eventfd2, 2) + MIPS_SYS(sys_epoll_create1, 1) + MIPS_SYS(sys_dup3, 3) + MIPS_SYS(sys_pipe2, 2) + MIPS_SYS(sys_inotify_init1, 1) }; You can drop this bit as there's already a patch in the works which adds the new syscall numbers: http://patchwork.ozlabs.org/patch/102241/ (the earlier fix for sigaltstack is still needed). There are also some bits of your patch which use hardcoded tabs; these should be spaces. (Yes, existing code is sometimes not consistent; we tend to convert gradually as we touch code.) Otherwise I think it looks good. Thanks again -- PMM
Re: [Qemu-devel] PATCH: fix qemu-mips[el]-static to work with debian squeeze/sid chroot
On Mar 05 Jul 2011 07:08:23 Wesley W. Terpstra escribió: I also recently tried to get a mipsel debian/sid chroot running under my amd64/squeeze system. As posted by Lisandro earlier this month, it didn't work. ;-) There are several problems, the most glaring of which the attached patch fixes. I'll break down the changes: Hi! I tried this patch (patched the current qemu in Debian) and I can happily say it works :-) Thanks everyone :-) -- rata hmm, el enchufe hace chispas... -- rata ha dejado este servidor (Leaving). marga ouch Visto en #lugfi, irc.freenode.net Lisandro Damián Nicanor Pérez Meyer http://perezmeyer.com.ar/ http://perezmeyer.blogspot.com/ signature.asc Description: This is a digitally signed message part.
