kvmtool, unless told otherwise, will do its best to make sure that a kernel successfully boots in a virtual machine. It does things like automatically creating a rootfs and adding 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. So always use --nodefaults to allow a test to run. kvmtool can also be too verbose when running a virtual machine, and this is controlled by several 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.eli...@arm.com> --- scripts/common.bash | 10 +++++----- scripts/vmm.bash | 13 +++++++++++++ 2 files changed, 18 insertions(+), 5 deletions(-) diff --git a/scripts/common.bash b/scripts/common.bash index 0645235d8baa..ee0ae71948c2 100644 --- a/scripts/common.bash +++ b/scripts/common.bash @@ -56,7 +56,7 @@ function for_each_unittest() # because qemu interprets the first argument after # -append as a kernel parameter. test_args="" - opts="" + opts="${vmm_opts[$TARGET:default_opts]}" groups="" arch="" machine="" @@ -70,13 +70,13 @@ function for_each_unittest() elif [[ $line =~ ^test_args\ *=\ *(.*)$ ]]; then test_args="${vmm_opts[$TARGET:args]} ${BASH_REMATCH[1]}" elif [[ $TARGET = "qemu" ]] && [[ $line =~ ^(extra_params|qemu_params)\ *=\ *'"""'(.*)$ ]]; then - opts=$(parse_opts ${BASH_REMATCH[2]}$'\n' $fd) + opts="${vmm_opts[$TARGET:default_opts]} $(parse_opts ${BASH_REMATCH[2]}$'\n' $fd)" elif [[ $TARGET = "qemu" ]] && [[ $line =~ ^(extra_params|qemu_params)\ *=\ *(.*)$ ]]; then - opts=${BASH_REMATCH[2]} + opts="${vmm_opts[$TARGET:default_opts]} ${BASH_REMATCH[2]}" elif [[ $TARGET = "kvmtool" ]] && [[ $line =~ ^kvmtool_params\ *=\ *'"""'(.*)$ ]]; then - opts=$(parse_opts ${BASH_REMATCH[1]}$'\n' $fd) + opts="${vmm_opts[$TARGET:default_opts]} $(parse_opts ${BASH_REMATCH[1]}$'\n' $fd)" elif [[ $TARGET = "kvmtool" ]] && [[ $line =~ ^kvmtool_params\ *=\ *(.*)$ ]]; then - opts=${BASH_REMATCH[1]} + opts="${vmm_opts[$TARGET:default_opts]} ${BASH_REMATCH[1]}" elif [[ $line =~ ^groups\ *=\ *(.*)$ ]]; then groups=${BASH_REMATCH[1]} elif [[ $line =~ ^arch\ *=\ *(.*)$ ]]; then diff --git a/scripts/vmm.bash b/scripts/vmm.bash index 20968f2e6b10..d24a4c4b8713 100644 --- a/scripts/vmm.bash +++ b/scripts/vmm.bash @@ -1,5 +1,16 @@ source config.mak +# 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 +: "${KVMTOOL_DEFAULT_OPTS:="--nodefaults --network mode=none --loglevel=warning"}" + ############################################################################## # qemu_fixup_return_code translates the ambiguous exit status in Table1 to that # in Table2. Table3 simply documents the complete status table. @@ -87,12 +98,14 @@ declare -A vmm_opts=( [qemu:kernel]='-kernel' [qemu:args]='-append' [qemu:initrd]='-initrd' + [qemu:default_opts]='' [qemu:fixup_return_code]=qemu_fixup_return_code [kvmtool:nr_cpus]='--cpus' [kvmtool:kernel]='--kernel' [kvmtool:args]='--params' [kvmtool:initrd]='--initrd' + [kvmtool:default_opts]="$KVMTOOL_DEFAULT_OPTS" [kvmtool:fixup_return_code]=kvmtool_fixup_return_code ) -- 2.49.0