kvmtool, unless told otherwise, will do its best to make sure that a kernel
successfully boots in a virtual machine. Among things like automatically
creating a rootfs, it also adds extra parameters to the kernel command
line. This is actively harmful to kvm-unit-tests, because some tests parse
the kernel command line and they will fail if they encounter the options
added by kvmtool.
Fortunately for us, kvmtool commit 5613ae26b998 ("Add --nodefaults command
line argument") addded the --nodefaults kvmtool parameter which disables
all the implicit virtual machine configuration that cannot be disabled by
using other parameters, like modifying the kernel command line. Always use
--nodefaults to allow a test to run.
kvmtool can be too verbose when running a virtual machine, and this is
controlled with parameters. Add those to the default kvmtool command line
to reduce this verbosity to a minimum.
Before:
$ vm run arm/selftest.flat --cpus 2 --mem 256 --params "setup smp=2 mem=256"
Info: # lkvm run -k arm/selftest.flat -m 256 -c 2 --name guest-5035
Unknown subtest
EXIT: STATUS=127
Warning: KVM compatibility warning.
virtio-9p device was not detected.
While you have requested a virtio-9p device, the guest kernel did not initialize it.
Please make sure that the guest kernel was compiled with CONFIG_NET_9P_VIRTIO=y enabled in .config.
Warning: KVM compatibility warning.
virtio-net device was not detected.
While you have requested a virtio-net device, the guest kernel did not initialize it.
Please make sure that the guest kernel was compiled with CONFIG_VIRTIO_NET=y enabled in .config.
Info: KVM session ended normally.
After:
$ vm run arm/selftest.flat --nodefaults --network mode=none --loglevel=warning --cpus 2 --mem 256 --params "setup smp=2 mem=256"
PASS: selftest: setup: smp: number of CPUs matches expectation
INFO: selftest: setup: smp: found 2 CPUs
PASS: selftest: setup: mem: memory size matches expectation
INFO: selftest: setup: mem: found 256 MB
SUMMARY: 2 tests
EXIT: STATUS=1
Note that KVMTOOL_DEFAULT_OPTS can be overwritten by an environment
variable with the same name, but it's not documented in the help string for
run_tests.sh. This has been done on purpose, since overwritting
KVMTOOL_DEFAULT_OPTS should only be necessary for debugging or development
purposes.
Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
---
scripts/runtime.bash | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/scripts/runtime.bash b/scripts/runtime.bash
index 55d58eef9c7c..abfd1e67b2ef 100644
--- a/scripts/runtime.bash
+++ b/scripts/runtime.bash
@@ -2,6 +2,17 @@
: "${MAX_SMP:=$(getconf _NPROCESSORS_ONLN)}"
: "${TIMEOUT:=90s}"
+# The following parameters are enabled by default when running a test with
+# kvmtool:
+# --nodefaults: suppress VM configuration that cannot be disabled otherwise
+# (like modifying the supplied kernel command line). Tests that
+# use the command line will fail without this parameter.
+# --network mode=none: do not create a network device. kvmtool tries to help the
+# user by automatically create one, and then prints a warning
+# when the VM terminates if the device hasn't been initialized.
+# --loglevel=warning: reduce verbosity
+: "${KVMTOOL_DEFAULT_OPTS:="--nodefaults --network mode=none --loglevel=warning"}"
+
PASS() { echo -ne "\e[32mPASS\e[0m"; }
SKIP() { echo -ne "\e[33mSKIP\e[0m"; }
FAIL() { echo -ne "\e[31mFAIL\e[0m"; }
@@ -103,7 +114,7 @@ function run()
opts="-smp $smp $qemu_opts"
;;
kvmtool)
- opts="--cpus $smp $kvmtool_opts"
+ opts="$KVMTOOL_DEFAULT_OPTS --cpus $smp $kvmtool_opts"
;;
esac
--
2.47.1
