Hi,
I am trying to get vserver work on the armel architecture. The hardware
used is a Marvell SheevaPlug with Debian Squeeze.
The first step was to compile the kernel. This only required adding one
missing "#include <linux/vs_memory.h>" to arch/arm/include/asm/tlb.h
after the line " #else /* !CONFIG_MMU */". With this small fix, the
kernel compiles and boots without any errors.
The next thing to do is the userspace utility. The main problem here is
that the ABI for calling linux system calls has changed. I've attached a
patch which fixes this with an appropriate #ifdef. The program compiles
fine with this patch and system calls seem to work. Since dietlibc is
not yet working on armel, I had to compile util-vserver with glibc. I
could already create a new vserver using the following command (before
doing /etc/init.d/util-vserver start):
vserver test build -m debootstrap --hostname test --rootdir /mnt/stick/
--interface eth0:192.168.1.21/24 -- -d lenny
However, starting the vserver using "vserver test start" fails with the
following error message:
/proc/uptime can not be accessed. Usually, this is caused by
procfs-security. Please read the FAQ for more details
http://linux-vserver.org/Proc-Security
After running "/etc/init.d/util-vserver start", trying to start the
vserver using "vserver test start" fails with a different error message:
vspace: clone(): No space left on device
Here is the strace output line of the failing clone system call:
clone(child_stack=0, flags=CLONE_VFORK|CLONE_NEWNS|SIGCHLD) = -1 ENOSPC
(No space left on device)
Some debugging in /etc/init.d/util-vserver showed that this problem
occurs after running the mount_cgroup function. Have you got any hints
about how to resolve this problem?
I've now finally found a workaround: When running
"/etc/init.d/vprocunhide start" and not "/etc/init.d/util-vserver
start", it is possible to start and use the vserver. When doing so, the
clone system call works successfully even though it uses exactly the
same parameters as the failing call above:
clone(child_stack=0, flags=CLONE_VFORK|CLONE_NEWNS|SIGCHLD) = 7149
Regards
Jakob Lell
Index: lib/syscall-alternative.h
===================================================================
--- lib/syscall-alternative.h (revision 2877)
+++ lib/syscall-alternative.h (working copy)
@@ -90,9 +90,35 @@
#elif defined(__arm__)
+#ifdef __ARM_EABI__
+
/* The Arm calling convention uses stack args after four arguments
but the Linux kernel gets up to seven arguments in registers.
+ scnr: r7
+ args: a1(r0), a2(r1), a3(r2), a4(r3), a5(r4), a6(r5),
+ sret: r0(r0)
+ serr: (sret >= (unsigned)-EMAXERRNO)
+ call: swi
+ clob: memory
+ move: mov $dR,$sR
+*/
+
+#define __sysc_max_err 125
+
+#define __sysc_cmd(n) "swi $0x0"
+
+#define __sysc_regs "r0", "r1", "r2", "r3", "r4", "r5"
+#define __sysc_reg_cid "r7"
+#define __sysc_reg_ret "r0"
+
+#warning syscall arch armel not tested yet
+
+#else
+
+/* The Arm calling convention uses stack args after four arguments
+ but the Linux kernel gets up to seven arguments in registers.
+
scnr: imm
args: a1(r0), a2(r1), a3(r2), a4(r3), a5(r4), a6(r5),
sret: r0(r0)
@@ -111,6 +137,7 @@
#warning syscall arch arm not tested yet
+#endif
/* *****************************************
Received on Fri Feb 19 11:41:25 2010