I've got it if -O2 compilation option used.
| cr-restore.c:1069:5: error: ‘ret’ may be used uninitialized in this function [-Werror=uninitialized]
| sockets.c:1145:7: error: ‘sk’ may be used uninitialized in this function [-Werror=uninitialized]
In first case 'ret' indeed might be uninitialized, and
in second case "goto err" was called too early. Fix them both.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
* kid -> child
* First letter should be uppercase
* Misc typos in messages and comments
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
v2: strlen() check removed from parse_ns_string()
Now '-n' option must be followed by namespaces tags, separated by commas.
Currently, only "uts" namespace is supported.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
cr-restore.c: In function ‘fixup_vma_fds’:
cr-restore.c:578:4: error: format ‘%d’ expects type ‘int’, but argument 6 has type ‘long unsigned int’
cr-restore.c: In function ‘sigreturn_restore’:
cr-restore.c:1693:4: error: format ‘%li’ expects type ‘long int’, but argument 4 has type ‘int’
cr-restore.c:1738:3: error: format ‘%d’ expects type ‘int’, but argument 4 has type ‘long int’
cr-restore.c:1751:3: error: format ‘%d’ expects type ‘int’, but argument 4 has type ‘long int’
cr-restore.c:1755:3: error: format ‘%d’ expects type ‘int’, but argument 3 has type ‘long int’
cr-restore.c:1868:4: error: format ‘%8p’ expects type ‘void *’, but argument 3 has type ‘long int’
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This is a standard convention to print error message (i.e. strerror(errno))
at the end of line, like this:
Cannot remove file: Permission denied
So pr_perror is fixed to follow this convention (using GNU extension
%m helps a lot here). Unfortunately, due to this we have to make
pr_perror() print a new line character, too, so we had to strip it
from the all pr_perror() invocations.
That (appending a newline) also makes pr_perror() a black sheep
in the herd of pr_* helpers, but what can we do? Worst case scenario
is an extra newline after an error message, not too harmful.
An alternative approach (stripping the newline from the passed format
string and re-adding it) was discussed thoroughly, and it was decided
that such a hack looks a bit too dirty.
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Found using clang:
cr-restore.c:796:8: error: use of unary operator that may be intended as compound assignment (+=)
size =+ ret;
^~
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Dumping is simple. All but secbits can be read from proc, secbits
are got from parasite.
Restoring is a bit tricky -- when you change anything on kernel
cred's struct it performs sophisticated checks and can change
some more stuff than requested, so the creds restoration procedure
is carefully commented step-by-step.
Another thing to mention is that creds are restored after everything
else, i.e. right before performing final threads sync and sigreturns.
This is done to avoid potential problems with insufficient caps for
restoring other stuff (e.g. CAP_DAC_OVERRIDE or zero euid is most
likely required for opening any image file and the notorious control
/proc/sys/kernel/ns_last_pid, which in turn is performed till the
very last moment).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Otherwise if restored task exit we get error message in form
| Error (cr-restore.c:1302): 7244 exited, status=0
while restored task simply finished working.
Pointed-out-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Only two fields are modifiable -- hostname and domainname. So
read them on dump and write on restore.
File format is simple --
u32 magic
u32 length of nodename
u8[] nodename string
u32 length of domainname
u8[] domainname string
For OpenVZ we can write the release at the end, but this is later.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
New option -n to dump/restore namespaces.
Fork the namespaces dumping task and write a helper for switching a namespace.
Prepare the restorer code for restoring namespaces before root task.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
In order to restore task in namespaces we'll have to clone() them,
not fork. Thus switch the restorer into using clone.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
I will need them in the place where we restore the root task.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Timers are dumped from inside parasite code, the format is plain -- just
3 pairs of interval/value one-by-one.
The restoration occurs in two stages -- first prepare the timer values in
restorer (and check for sanity), then setup the timers in the latest stage
before actually calling the sigreturn.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Dump the core-pid.img file only. On restore select the way of killing
task based on his exit_code -- exit or kill with a signal. Before dying
unblock all the handlers and set SIG_DFL to it (to make the dead signal
other than KILL be deliverable).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
The absent image file on shared resources preparation now means -- no resources
for this pid (zombies will not have these files).
This is not the most elegant solution, but I don't have anything better in mind.
Need to think over, all the more so we're most likely about to reimplement the
way image is stored some day in the future.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Kill all the macros for reading/writing image parts. New API looks like
* write_img_buf/write_img
Write an object into an image. Reports 0 for OK, -1 for error. The _buf
version accepts object size as an argument, the other one uses sizeof()
* read_img_buf/read_img
Reads an object from image. Reports 0 for OK, -1 for error or EOF.
* read_img_buf_eof/read_img
Reads an object from image. Reports 1 for OK, 0 for EOF and -1 for error.
This is not symmetrical with the previous one, but it was done deliberately
to make it possible to write code like
ret = read_img_bug_eof();
if (ret <= 0)
return ret; /* 0 means OK, all is done, -1 means error was met */.
... /* 1 means object was read, can proceed */
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
It's not needed anymore, it was handing cases
where no fork-with-pid functionality were in
kernel, but now it's simply unneeded.
Also drop redundant getpid() calls.
Passes all tests (except fork test which known to fail).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parllels.com>
After Andrey's work with making restorer a regular .o file we can do it
(the pthread00 test doesn't fail on it).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Handle SIGCHLD and if someone failed, nr_in_progress is set to -1.
If crtools notices that nr_in_progress is negative, it kills all
tasks.
v2: * Use named constants for task_entries->start in restorer.c
* Use SA_NOCLDWAIT when setting sigchild handler,
this makes sigchild handler simpler.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Now we have only one mutex nr_in_progress, it says how many
tasks are not restored yet. A negative value signs that someone
failed.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
v2: add FIXME for linking restorer-log.c and restorer.c by ld
I don't know how to do it now.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Before this patch the restorer's code is linked in crtools and then
we copied functions from it. In this case all function should
be inline and we can't use a global variables.
I suggest to make it like parasite. The restorer's code is isolated in
own file and will be copied wholly. The restorer's code is compiled as
position-independent code, so we can use functions and global variale
(E.g. to save descriptor for log messages).
v2: correct indentions in a separate patch
v3: introduce a variable restore_task_exec_start symmetrical to
restore_thread_exec_start
v4: don't give command in restorer_thread()
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
This patch prepares code to handle errors. In the near future
we will handle SIGCHLD. If a restore of one task fails, we will
send a signal to other for completing.
For this we should have ability to wait until all task wills be
restored. This patch does it.
v2: Don't wait children.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Sometime we want to have a shared mapping in restorer. E.g. A storage
for shared memory entries. This entries contains locks, which should
be released in restorer.
v2: fixed according to Pavel's comments
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
There is no need to use sys_ versions of libc functions
when we run in non relocated code. It's a leftover from
early testing time. Fix it.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reprimand to commits bd8b2b0f and d0a6e9a1 authors for not
cleaning after themselves...
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This one is skipped at restore and leaves an open core file
in target task's fdtable.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Otherwise it pops up after restore in target task's fdtable.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
create_pipe() may restore up to 3 descriptors. They may be both ends
of pipes and a target descriptor. The image fd may hold any of them.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This reverts commit 46c613cc7d869ebf39532a1def054de7678e441f.
Andrey posted a proper fix for it. Moreover, the problem in first
place was initiated by a parasite application running during test
case, crtools knows nothing about.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
It's perfectly fine to reuse descriptors here,
since we use plain pipe() call and it migh choose
the descriptor which we need after.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
The old code carried the path through the stack. Now we have
pstree_pid and handy helpers to get one.
Tested by pipes00 test from zdtm (it forks).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Instead of passing self-vma file path to restorer
code simply open it before restore_task call and
pass descriptor instead. This saves some memory.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This allows us to get rid of open-coded "/proc/pid/X".
Based-on-patch-from: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
It basically reverts e189efc1763d9cae55e1cafd7aff7ffef6e47303
which was overdone one.
Reported-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Some process can share one struct file-s, we may find them by "object IDs".
A file descriptor is opened in one process and send to other via unix socket.
The procedure of restoring files contains four stages.
* Collect data about all file's descriptors
On this stage we find process which will restore a file descriptor and
create a list of processes, who should get this descriptor.
* Create datagrams unix sockets
If a file descriptor should be received, a unix socket is created
instead of it.
* Open file descriptors
A process with the least pid opens a file and sends this file
descriptors to all one who wait it.
* Receive file descriptors.
When we were thinking up this algoritm, we wanted to minimize a number
of context switches. A number of context switches is proportional of a
number of processes.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Restorer does really restore shared memory (including page
contents restore) only on master process, while all other
processes do open such memory area via map_files/ procfs entry
so that we might have a situation when shared VMA is present
in some particular core-%d.img file but it's not listed in
collected shmems array and find_shmem_by_pid will return NULL.
This is perfectly fine, be ready for that.
Another issue is that shared memory might look like
CR_FD_SHMEM: /home/cyrill/projects/kernel/crtools/shmem-2641.img
----------------------------------------
0x7f2200775000-0x7f2200776000 id 19664
0x7f2200776000-0x7f2200777000 id 19663
----------------------------------------
So vma area is [x;y) range and we should distinguish two
shmem lookup cases
- one when we search for page in shmem area
- second when we lookup shmem area in collected ranges
They both have a different lookup conditions so single
find_shmem splitted into two helpers find_shmem and
find_shmem_page as appropriate.
This patch finally fixes the three process asynchronious
shared memory updates test-case.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
