On Thu, Oct 21, 2010 at 12:46:33PM +0900, Isaku Yamahata wrote: > On Wed, Oct 20, 2010 at 12:00:11PM +0200, Michael S. Tsirkin wrote: > > On Wed, Oct 20, 2010 at 05:18:56PM +0900, Isaku Yamahata wrote: > > > glue pcie_push_attention_button command. > > > > > > Signed-off-by: Isaku Yamahata <yamah...@valinux.co.jp> > > > > So as a high level command, I think we need to > > think about how to tie this into pci_add/pci_del. > > Right? > > Maybe or maybe not. > I'm not sure it's a good idea to tie it to pci_add/pci_del > in the first place. > The specification says only that pushing the button is just to > initiate the hot-plug operation. It means only a notification. > The spec says nothing about the concrete action from OS when > the button is pushed. It's up to OS. > > For example. > OS may start to probe the slot. > OS may start to quiescence the device. > OS is allowed to ignore the notification. > OS may propagate the notification to the management software, > and it would pop up the dialog to the user for further operation. >
pci_add/pci_del really behave in the same way. There's no way to force the OS to respond. We only use ACPI for now, but for express I expect standard interfaces will work better long term. > > As a low level command, this is not really useful unless > > there is an event on LED status change and a way > > to get info on LED status. > > Right? > > No. Guest OS can provide users those infos, and Linux does > via sysfs. So there already is a way to know LED status. > This is the reason why LED status change event stuff has low > priority in my TODO list. But that's in the guest. -- MST
