restore: Add debug info on premapped VMA address

| Map 0x0000000000400000-0x00000000004a5000 0x0000000000000000 vma
| 	premap 0x0000000000400000-0x00000000004a5000 -> 00007f26eb898000

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
restore: Return error instead of BUG_ON on image corruption

In case if there image corruption and page entry addres
is invalid -- exit out gracefully instead of BUG_ON hammer.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
pstree: Add more debug output for prepare_pstree_kobj_ids

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
files-reg: Print file name on error

In case if there some error happened better to
know which exactly file failed on open, for example

 | Error (files-reg.c:535): Can't open file /lib64/libgcc_s-4.4.7-20120601.so.1 on restore: No such file or directory

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
restore: Validate page address in restore_priv_vma_content

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
zdtm: add a test case for pending signals

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
protobuf: add a new description for saving siginfo-s

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
crtools: add a callback to show signal=*.img

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
crtools: add image contants for pending signals (v2)

v2: rename images

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
crtools: dump pending signals (v4)

PTRACE_PEEKSIGINFO is used for received pending signals,
then all signal are sent back and saved in a image.

v2: rework according with the new kernel interface
v3: rework according with the newrest kernel interface
v4: fix error handling

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
crtools: restore pending signals (v4)

Read siginfo-s from images and send them to itself by sigqueueinfo.

Thread signals cannot be restored in restore_thread_common, because
it blocks SIGCHLD, which used for error detecting.

v2: Don't remap task_args and thread_args
v3: fix error handling
v4: cosmetic clean up

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
check: check PTRACE_PEEKSIGINFO and sigqueueinfo with positive si_code (v2)

v2: fix indentations.

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
restore: set up correct sa_restorer for SIGCHLD handler (v3)

Alexander, could you help me with ARM? I found in glibc sources, that
sa_restoer should look like this:

ports/sysdeps/unix/sysv/linux/arm/sigrestorer.S
....
ENTRY(__cr_restore_rt)
        CFI
        mov     r7, $SYS_ify(rt_sigreturn)
        swi     0x0
        .fnend
END(__cr_restore_rt)

v2: Move architecture-dependent code in the proper place
v3: Don't add a separate handler for collecting zombies

Cc: Alexander Kartashov <alekskartashov@parallels.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
restore: read core.img before forking to know a child state

It's necessary to get a number of zombies.

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
restore: collect signals from zombies (v4)

Each zombie sends SIGCHLD to parent. crtools restores all pending
signals, so all other signals should be collected.

Here is a problems, that signals SIGCHLD can be merged, but crtools
should be sure, that all signals are collected.

For that a zombie locks a global zombie_lock, which is released by
parent.

This operation should be done between CR_STATE_RESTORE and
CR_STATE_RESTORE_SIGCHLD.

Here is one more CR_STATE_RESTORE_ZOMBIES, whic is used for waiting all
zombies.

v2: clean up
v3: rework synchronization
v4: rework without additional CR_STATE-s

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
zdtm.sh: add static/sigpending in the default set

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
arm: added the descriptions of the syscalls pread64, rt_sigqueueinfo, signalfd4, rt_tgsigqueueinfo

Signed-off-by: Alexander Kartashov <alekskartashov@parallels.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
arm: added architecture-specific implementation of __cr_restore_rt

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