hyperv_keyboard invokes serio_interrupt(), which needs a valid serio driver like atkbd.c. atkbd.c depends on libps2.c because it invokes ps2_command(). libps2.c depends on i8042.c because it invokes i8042_check_port_owner(). As a result, hyperv_keyboard actually depends on i8042.c.
For a Generation 2 Hyper-V VM (meaning no i8042 device emulated), if a Linux VM (like Arch Linux) happens to configure CONFIG_SERIO_I8042=m rather than =y, atkbd.ko can't load because i8042.ko can't load(due to no i8042 device emulated) and finally hyperv_keyboard can't work and the user can't input: https://bugs.archlinux.org/task/39820 (Ubuntu/RHEL/SUSE aren't affected since they use CONFIG_SERIO_I8042=y) Decoupling the dependency between hyperv_keyboard and i8042 needs non-trivial efforts and is hence a long term goal. For now, let's make the dependency explicit so people can beware of this. Thank Claudio for the initial reporting, investigation and suggesting the fix. Signed-off-by: Dexuan Cui <de...@microsoft.com> Reported-by: Claudio Latini <claudio.lat...@live.com> Cc: K. Y. Srinivasan <k...@microsoft.com> --- drivers/input/serio/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig index bc2d474..3277bff 100644 --- a/drivers/input/serio/Kconfig +++ b/drivers/input/serio/Kconfig @@ -273,7 +273,7 @@ config SERIO_OLPC_APSP config HYPERV_KEYBOARD tristate "Microsoft Synthetic Keyboard driver" - depends on HYPERV + depends on HYPERV && SERIO_I8042=y default HYPERV help Select this option to enable the Hyper-V Keyboard driver. -- 1.9.1 _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
