When AIO context is set up kernel does two things:

1. creates an in-kernel aioctx object
2. maps a ring into process memory

The 2nd thing gives us all the needed information
about how the AIO was set up. So, in order to dump
one we need to pick the ring in memory and get all
the information we need from it.

One thing to note -- we cannot dump tasks if there
are any AIO requests pending. So we also need to
go to parasite and check the ring to be empty.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Our CPU_CAP_s are bitmaps so if cpuinfo image is present
but we require only FPU to check we need to check this
bit being sole on comman line.

It was a typo in first place which caused statement to
be false always (it's not a problem though and not a
@stable candidate because with this mistake we fall
into strict match cpu mode).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We may not have permissions for this.

Reported-by: Mr Jenkins
Fixes: 7dbd38db ("zdtm: set additional groups along with uids and gids")
Cc: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

/tmp/ccq2xzf8.s: Assembler messages:
/tmp/ccq2xzf8.s:5748: Error: thumb conditional instruction should be in IT block -- strexeq r1,r2,[r3]'

Cc: Alexander Kartashov <alekskartashov@parallels.com>
Cc: Ruslan Kuprieiv <kupruser@gmail.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We will need to detect aio mappings soon, so this is a preparation,
that makes future patching simpler.

Also move aufs stat-ing into aufs code to keep more aufs logic in
one place.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We may not have permissions for this.

Reported-by: Mr Jenkins
Fixes: 7dbd38db ("zdtm: set additional groups along with uids and gids")
Cc: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Acked-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Don't use an uninitialized variable to create a path pattern.

v2: fix the comment
v3: don't use readlink -m, which isn't supported by busybox

Cc: Christopher Covington <cov@codeaurora.org>
Reported-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Reviewed-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Cc: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Tested-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Lets simulate some errors and check what
error will be returned by service.

v2, fix tests accordingly to new errorlist
v3, fix tests accordingly to new errorlist, again
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>

It turned out we didn't have one, though recent 3.19-merge-window
kernel would crash on that test.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

v2, set cr_errno only if we have one that is != 0
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Inspired by static/console test.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

/dev/ttyN are the virtual terminals which are provided
by the system with major 4 and minor 1..63.
You can run some program on ttyN by pressing alt+ctrl+FN
and running it manualy or by using open(openvt nowadays).

This patch also allows us to run all our tests from a vt.

v2, style fix + using linux/vt.h for constants
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Currently zdtm doesn't set additional groups when running
tests. It sets uids and gids to some non-root values, but
additional groups remain untouched, which allows tests
to inherit groups list, which leads to different
behaviour depending on a way you run tests.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

This is a very common error when using criu.

The problem here is that we need to somehow transfer cr_errno
from one process to another. I suggest using pipe to give
one end to children and read cr_errno on other after restore
is finished.

v2, Pavel suggested putting errno into shared task_entries.
v3. and he also suggested using cmpxchg
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Some packages monitor the FS /.

(00.573051) irmap: Scanning /. hint
(00.573053) irmap: Stat for 110025: INO - 2891453, DEV - 64768
(00.573055) irmap: Refresh stat for /.
(00.573063) irmap: MNTNS_ROOT: 110025, PATH: /., INO: 2891453, DEV: 64768
Signed-off-by: Nikolay Plotnik <nikolay.plotnik@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

In case if we're migrating to another node where @total_sleep_time
has a big value we might fail here because we don't support tracking
of @total_sleep_time at all, neither we can somehow restore it without
kernel patching (and it's hardly if ever be allowed in vanilla kernel).

Thus simply remember @total_sleep_time value before and after c/r stage
removing it from the computations.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Add comment to inherit_fd_reused() explaining how an inherit fd may be
closed or reused outside the inherit fd logic.
Signed-off-by: Saied Kazemi <saied@google.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

(00.312396)      4: Error (pipes.c:301): Not enough room for pipe 562178190 identifier string

Reported-by: Mr Jenkinks
Cc: Saied Kazemi <saied@google.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It's for more natural adding of new else-if branch for aio.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Reported-by: Paschalis Mpeis <paschalis.mpeis@ed.ac.uk>
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Hi Saied,

This patch adds your test in the criu test system.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We may not have permissions for this.
Reported-by: Ruslan Kuprieiev <kupruser@gmail.com>
Cc: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

There are cases where a process's file descriptor cannot be restored
from the checkpoint images.  For example, a pipe file descriptor with
one end in the checkpointed process and the other end in a separate
process (that was not part of the checkpointed process tree) cannot be
restored because after checkpoint the pipe will be broken.

There are also cases where the user wants to use a new file during
restore instead of the original file at checkpoint time.  For example,
the user wants to change the log file of a process from /path/to/oldlog
to /path/to/newlog.

In these cases, criu's caller should set up a new file descriptor to be
inherited by the restored process and specify the file descriptor with the
--inherit-fd command line option.  The argument of --inherit-fd has the
format fd[%d]:%s, where %d tells criu which of its own file descriptors
to use for restoring the file identified by %s.

As a debugging aid, if the argument has the format debug[%d]:%s, it tells
criu to write out the string after colon to the file descriptor %d.  This
can be used, for example, as an easy way to leave a "restore marker"
in the output stream of the process.

It's important to note that inherit fd support breaks applications
that depend on the state of the file descriptor being inherited.  So,
consider inherit fd only for specific use cases that you know for sure
won't break the application.

For examples please visit http://criu.org/Category:HOWTO.

v2: Added a check in send_fd_to_self() to avoid closing an inherit fd.
    Also, as an extra measure of caution, added checks in the inherit fd
    look up functions to make sure that the inherit fd hasn't been reused.
    The patch also includes minor cosmetic changes.
Signed-off-by: Saied Kazemi <saied@google.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>