From: Jason Wessel Date: Fri, 29 May 2009 18:34:17 +0000 (-0500) Subject: USB: usb_serial: only allow sysrq on a console port X-Git-Tag: v2.6.31-rc1~304^2~51 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=568d422e9cf52b7b26d2e026ae1617971f62b560;p=pandora-kernel.git USB: usb_serial: only allow sysrq on a console port The only time a sysrq should get processed is if the attached device is a console. This is intended to protect sysrq execution on a host connected with a terminal program. Here is the problem scenario: host A <-- rs232 link --> host B Host A is using mincom and a usb pl2303 device to connect to host b which is a linux system with a usb pl2303 device acting as the serial console. When host B is rebooted the pl2303 emits random junk characters on reset. These character sequences contain serial break signals most of the time and when translated to a sysrq have caused host A to get random processes killed, reboots or power down. It is true that in this setup with this patch host B might still have the same problem as host A if you reboot host A. In most cases host A is a development host which seldom gets rebooted, and you could turn off sysrq temporarily on host B if you need to reboot host A. Signed-off-by: Jason Wessel Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed