Allowing the input to be specified for file-based serial ports allows
the user of pipes as input/output. That enables kgdb over serial.
TEST=
Build a kernel with support for gdb
```
make x86_64_defconfig
make kvmconfig
./scripts/config --enable GDB_SCRIPTS
./scripts/config --enable KGDB
./scripts/config --enable KGDB_SERIAL_CONSOLE
./scripts/config --enable KGDB_LOW_LEVEL_TRAP
./scripts/config --enable KGDB_KDB
./scripts/config --enable KDB_KEYBOARD
./scripts/config --enable GDB_SCRIPTS
./scripts/config --set-val KDB_CONTINUE_CATASTROPHIC 0
make -j33
```
Setup devices for PTYs
To make sure crosvm doesn't create an ordinary file if socat is started
after it, create these named pipes first:
```
mkfifo ~/console_{in,out} ~/kgdb_{in,out}
```
Set up two PTYs: ~/kgdb for the debugger, and ~/serial for the console.
PTY ~/kgdb connects to ~/kgdb{in,out}, and ~/serial connects to
~/console{in,out}
```
socat -d -d -d \
'PIPE:$HOME/console_out,rdonly=1,nonblock=1,ignoreeof=1!!PIPE:$HOME/console_in,wronly=1' \
PTY,link=$HOME/serial,ctty,raw,echo=0
socat -d -d -d \
'PIPE:$HOME/kgdb_out,rdonly=1,nonblock=1,ignoreeof=1!!PIPE:$HOME/kgdb_in,wronly=1' \
PTY,link=$HOME/kgdb,ctty,raw,echo=0
```
Start crosvm with serial ports pointed at ~/console{in,out} and ~/kgdb{in,out}.
```
cargo run run -p 'init=/bin/sh panic=0 kgdboc=ttyS1,115200 kgdbwait kgdbcon' \
--serial type=file,path=$HOME/console_out,num=1,console=true,stdin=false,input=$HOME/console_in \
--serial type=file,path=$HOME/kgdb_out,input=$HOME/kgdb_in,num=2,console=false,stdin=false \
-r ~/rootfs.img \
~/src/linux/arch/x86/boot/bzImage
```
Start GDB
```
gdb vmlinux -ex "target remote /home/dgreid/kgdb"
```
To break into gdb, open up the serial console, mount /proc and send a SysRq
```
minicom -D ~/serial
mount -t proc none /proc
echo g > /proc/sysrq-trigger
```
Change-Id: I18a9c1087d38301df49de08eeae2f8559b03463a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/2151856
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: Dylan Reid <dgreid@chromium.org>
Commit-Queue: Dylan Reid <dgreid@chromium.org>
This is the first `cargo test` which uses a linux kernel binary in
testing crosvm's major functionality. To get that binary, the test tries
various sources which may be influenced by the enviroment. If need be,
the chromiumos kernel is downloaded via git, configured, and built so
that crosvm can use it. The resulting binary is cached so that other
tests which need it can run much quicker.
TEST=cargo test -- boot
BUG=None
Cq-Depend: chromium:1867729
Change-Id: I123441d358ef886e0d7369eaa4ebd87373026d99
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/1742924
Reviewed-by: Stephen Barber <smbarber@chromium.org>
Tested-by: Zach Reizner <zachr@chromium.org>
Commit-Queue: Zach Reizner <zachr@chromium.org>
Auto-Submit: Zach Reizner <zachr@chromium.org>
