From: Daniel Thompson Date: Wed, 16 Jul 2014 13:30:13 +0000 (+0100) Subject: tty: kgdb_nmi: Automatically manage tty enable X-Git-Tag: omap-for-v3.17/fixes-against-rc2~165^2~16 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c8b29f049eb2645dd21e40a6613c09f15c731650;p=pandora-kernel.git tty: kgdb_nmi: Automatically manage tty enable At present it is not possible to boot with the ttyNMI0 console treating character input normally, instead character input triggers a prompt telling the user how to trigger the knock detector and enter the debugger. To use the console normally requires that kdb be entered and the nmi_console command be used to enable the console (or if only kgdb is present then gdb must directly manipulate the value of kgdb_nmi_tty_enabled). This patch automates the management of kgdb_nmi_tty_enabled by keeping track of the number of file handles that are open for reading and using that to determine how to tty should operate. The approach means that: 1. Behaviour before init starts is unchanged. 2. If the userspace runs a getty or some other interactive process on /dev/console (or explicitly on /dev/ttyNMI0) the tty will treat character input like any other tty. 3. If the userspace doesn't use /dev/console or if it uses /dev/console only to log messages (O_WRONLY) then the user prompt is retained. Signed-off-by: Daniel Thompson Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Cc: Jason Wessel Cc: kgdb-bugreport@lists.sourceforge.net Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed