As of QEMU commit a5804fcf7b22 ("9pfs: local: ignore O_NOATIME if we
don't have permissions") (in v5.1.0), QEMU handles O_NOATIME sanely, so
we don't need the LD_PRELOAD hack. Since we're adding a version check,
make the multidevs check based on the version, too.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
drgn was originally my side project, but for awhile now it's also been
my work project. Update the copyright headers to reflect this, and add a
copyright header to various files that were missing it.
Currently, vmtest runs a custom program as init in the guest that
communicates with the host via virtio-serial. This is a lot of C code
that turns out can be replaced with a shell script. In order to keep the
dependencies minimal, we use BusyBox.
The current implementation of vmtest has a few issues:
1. Building drgn for each kernel version on Travis is slow, mostly
because they don't all run in parallel.
2. For local, incremental testing, recreating the filesystem image and
rebuilding drgn is slow, and syncing the code to the filesystem image
is brittle.
3. The filesystem image is the only communication channel, and reading
the exit status from the filesystem image is awkward and fragile.
4. Creating and accessing the filesystem image requires root.
This reworks vmtest to use the build on the host via VirtFS with a
simple agent on the guest that can execute arbitrary commands and return
the exit status. This has a few more moving parts but is faster and
saner overall.