From 46eaea16279beb66a837f9f019225735806b9496 Mon Sep 17 00:00:00 2001 From: Samuel Ortiz Date: Wed, 24 Jul 2019 15:20:39 +0200 Subject: [PATCH] README: Fix kernel command line console argument We use the virtio console device now. Fixes: #116 Signed-off-by: Samuel Ortiz --- README.md | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/README.md b/README.md index 01a7f0738..6739e8bb4 100644 --- a/README.md +++ b/README.md @@ -168,6 +168,26 @@ $ sudo setcap cap_net_admin+ep ./cloud-hypervisor/target/release/cloud-hyperviso $ ./cloud-hypervisor/target/release/cloud-hypervisor \ --kernel ./linux-cloud-hypervisor/arch/x86/boot/compressed/vmlinux.bin \ --disk ./clear-29160-kvm.img \ + --cmdline "console=hvc0 reboot=k panic=1 nomodules i8042.noaux i8042.nomux i8042.nopnp i8042.dumbkbd root=/dev/vda3" \ + --cpus 4 \ + --memory size=1024M \ + --net "tap=,mac=,ip=,mask=" \ + --rng +``` + +The above example use the `virtio-console` device as the guest console, and this +device may not be enabled soon enough by the guest kernel to get early kernel +debug messages. + +When in need for earlier debug messages, using the legacy serial device based +console is preferred: + +``` +$ ./cloud-hypervisor/target/release/cloud-hypervisor \ + --kernel ./linux-cloud-hypervisor/arch/x86/boot/compressed/vmlinux.bin \ + --console off \ + --serial tty \ + --disk ./clear-29160-kvm.img \ --cmdline "console=ttyS0 reboot=k panic=1 nomodules i8042.noaux i8042.nomux i8042.nopnp i8042.dumbkbd root=/dev/vda3" \ --cpus 4 \ --memory size=1024M \ @@ -175,6 +195,7 @@ $ ./cloud-hypervisor/target/release/cloud-hypervisor \ --rng ``` + # 3. Status `cloud-hypervisor` is in a very early, pre-alpha stage. Use at your own risk!