Why should we have self-unmapping code in parasite?
It looks like, we can drop this code using simple sys_unmap()
injection (like that I did for `criu exec` action and for cases where we
failed to insert parasite by some reason, but still need to unmap remotes).
It's an RFC, so just a suggestion - maybe I miss something you have in
mind - please, describe that/those things.
My motivation is:
- less code, defined commands for PIE, one BUG() less, one jump to PIE less
- I'm making one 64-bit parasite on x86 instead of two 32 and 64 bit.
It works (branch 32-one-parasite) with long-jump in the beginning to
64-bit code from 32-bit task.
On parasite curing it sig-returns from 64-bit parasite to 32-bit task,
this point we're trapping in CRIU. After that we command parasite to
unmap itself, so it long-jumps again to parasite 64-bit code, unmaps,
we caught task after sys_unmap and the task is with 64-bit CS.
We can't set 32-bit registers after this - kernel checks that
registers set is the same on PTRACE_SETREGSET:
> > static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
> > struct iovec *kiov)
...
> > if (!regset || (kiov->iov_len % regset->size) != 0)
> > return -EINVAL;
So, to return again to 32-bit task I need sigreturn() again or add
long-jump with 32-bit CS.
I've disable that for 32-bit testing with (in compel_cure_remote):
- if (ctl->addr_cmd) {
+ if (ctl->addr_cmd && user_regs_native(&ctl->orig.regs)) {
And it works. It also works for native tasks, so why should we keep it?
travis-ci: success for compel: kill self-unmap in parasite
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
We use fds helpers in std plugin anyway
so just merge it in.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Providing infect functionality inside std plugin
doesn't look suite for me: the restorer has to define
dummy parasite_daemon_cmd/parasite_trap_cmd/parasite_cleanup
just to be able to compile with it.
So we have to define weak stubs right here in near future.
travis-ci: success for compel: The final infect move and install target
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
travis-ci: success for compel: The final infect move and install target
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
The routine was #if0ed for a while (taken from older compel), now it's
time to provide any generic version.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
And use it in CRIU directly instead:
- move syscalls into compel/arch/ARCH/plugins/std/syscalls
- drop old symlinks
- no build for 32bit on x86 as expected
- use std.built-in.o inside criu directly (compel_main stub)
- drop syscalls on x86 criu directory, I copied them already
in first compel commist, so we can't move them now, but
delete in place
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Plain "main" makes compilers unhappy since it's
known predefined name.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
prologue.h defines sys_recv() macro - let's use it by now
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Delete plugins/include/asm/std directory - let it be without plugin name.
Make symlinks to reuse criu's files, except those, which will
be deleted after libcompel from criu (like syscalls).
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
The plugin provides basic features as string copying, syscalls, printing.
Not used on its own by now but will be shipping by default with other
plugins.
With great help from Dmitry Safonov.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
