Date: Sat, 22 Aug 2009 18:25:55 +0200 From: Hans Petter Selasky <hselasky@c2i.net> To: Bruce Cran <bruce@cran.org.uk> Cc: Alexander Best <alexbestms@math.uni-muenster.de>, freebsd-usb@freebsd.org Subject: Re: kernel debugger and usb keyboard Message-ID: <200908221825.56855.hselasky@c2i.net> In-Reply-To: <20090822154807.0cf17700@gluon.draftnet> References: <permail-20090803185516f7e55a9d00006928-a_best01@message-id.uni-muenster.de> <200908032127.32353.hselasky@c2i.net> <20090822154807.0cf17700@gluon.draftnet>
index | next in thread | previous in thread | raw e-mail
On Saturday 22 August 2009 16:48:07 Bruce Cran wrote: > On Mon, 3 Aug 2009 21:27:30 +0200 > > Hans Petter Selasky <hselasky@c2i.net> wrote: > > On Monday 03 August 2009 20:55:16 Alexander Best wrote: > > > just tried settings `sysctl debug.kdb.panic = 1`. if i use this way > > > to enter the kernel debugger my usb keyboard works. if i type > > > "continue" however the kernel panics and the kernel debugger gets > > > yet entered again, but without the keyboard working. > > > > The USB controller which the keyboard is hooked onto will not work > > after panic has been entered, due to some state not being cleaned up. > > > > To increase the chance of the keyboard working on a panic, connect > > the keyboard to a separate USB controller. > > > > > i don't know how to produce backtraces since the keyboard doesn't > > > work. > > > > Ok. > > > > > the other way of entering the debugger without my keyboard working > > > was to simple press "ctrl+ast+esc". > > > > Yes, because most likely the DDB is entered directly from the USB > > keyboard code, and the USB stack does not allow function recursion in > > that case! > > USB keyboard support is now working in the debugger, but it seems > the USB stack hangs up if you exit out of the debugger, if the system > hasn't crashed and can keep running - the keyboard doesn't respond, and > unplugging and re-plugging it doesn't help. > > If I press Ctrl-Alt-Esc followed by "c" to continue, the output scrolls > up the window as if the Enter key is being held down. This is going to get fixed in a coming USB patchset. Stay tuned. --HPShelp
Want to link to this message? Use this
URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200908221825.56855.hselasky>