Link: https://github.com/containers/podman/issues/26073
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

Linux distributions use different dumpmachine outputs for the ARM
architecture. arm, armv6l, armv7l.
For the syscall annotation, these variants are standardized to “arm”.

Link: https://bugs.passt.top/show_bug.cgi?id=117
Signed-off-by: Julian Wundrak <julian@wundrak.net>
[sbrivio: Fix typo: assign from TARGET_ARCH, not from TARGET]
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

It looks like an easy win to prevent a number of possible security
flaws.

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

...instead of unconditionally trying to enable both: mmap2() is the
32-bit ARM variant for mmap() (and perhaps for other architectures),
bot if mmap() is available, valgrind will use that one.

This avoids seccomp.sh warning us about missing mmap2() if mmap() is
present, and is consistent with what we do in vhost-user code.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

In vhost-user mode, by default, create a second UNIX domain socket
accepting connections from passt-repair, with the usual listener
socket.

When we need to set or clear TCP_REPAIR on sockets, we'll send them
via SCM_RIGHTS to passt-repair, who sets the socket option values we
ask for.

To that end, introduce batched functions to request TCP_REPAIR
settings on sockets, so that we don't have to send a single message
for each socket, on migration. When needed, repair_flush() will
send the message and check for the reply.

Co-authored-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

Introduce facilities for guest migration on top of vhost-user
infrastructure.  Add migration facilities based on top of the current
vhost-user infrastructure, moving vu_migrate() and related functions
to migrate.c.

Versioned migration stages define function pointers to be called on
source or target, or data sections that need to be transferred.

The migration header consists of a magic number, a version number for the
encoding, and a "compat_version" which represents the oldest version which
is compatible with the current one.  We don't use it yet, but that allows
for the future possibility of backwards compatible protocol extensions.

Co-authored-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

The passt-repair helper is now merged, but alas it contains several small
bugs:
 * close() is not in the seccomp profile, meaning it will immediately
   SIGSYS when you make a request of it
 * The generated header, seccomp_repair.h isn't listed in .gitignore or
   removed by "make clean"

Fixes: 8c24301462c3 ("Introduce passt-repair")
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

A privileged helper to set/clear TCP_REPAIR on sockets on behalf of
passt. Not used yet.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

I don't think it's necessarily productive to check all the possible
error conditions in the Makefile, but this one is annoying: issue
'make' without a C compiler, then install one, and build again.

Then run passt and it will mysteriously terminate on epoll_wait(),
because seccomp.h is good enough to build against, but the resulting
seccomp filter doesn't allow any system call. Not really fun to debug.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

TARGET_ARCH is computed from '$(CC) -dumpmachine' using external
bash commands like echo, cut, tr and sed. This can be done using
make internal string functions.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>