From 7adfb1b91da4b02726e19d6b86355cad27ad1737 Mon Sep 17 00:00:00 2001 From: peter Date: Wed, 26 Oct 2005 22:40:07 +0000 Subject: Commit something we found useful at work at one point. Add sysctls for debug.kdb.panic and debug.kdb.trap alongside the existing debug.kdb.enter sysctl. 'panic' causes a panic, and 'trap' causes a page fault. We used these to ensure that crash dumps succeed from those two common failure modes. This avoids the need for creating a 'panic' kld module. --- sys/kern/subr_kdb.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/sys/kern/subr_kdb.c b/sys/kern/subr_kdb.c index 3157578..634343c 100644 --- a/sys/kern/subr_kdb.c +++ b/sys/kern/subr_kdb.c @@ -63,6 +63,8 @@ SET_DECLARE(kdb_dbbe_set, struct kdb_dbbe); static int kdb_sysctl_available(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_current(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_enter(SYSCTL_HANDLER_ARGS); +static int kdb_sysctl_panic(SYSCTL_HANDLER_ARGS); +static int kdb_sysctl_trap(SYSCTL_HANDLER_ARGS); SYSCTL_NODE(_debug, OID_AUTO, kdb, CTLFLAG_RW, NULL, "KDB nodes"); @@ -75,6 +77,12 @@ SYSCTL_PROC(_debug_kdb, OID_AUTO, current, CTLTYPE_STRING | CTLFLAG_RW, 0, 0, SYSCTL_PROC(_debug_kdb, OID_AUTO, enter, CTLTYPE_INT | CTLFLAG_RW, 0, 0, kdb_sysctl_enter, "I", "set to enter the debugger"); +SYSCTL_PROC(_debug_kdb, OID_AUTO, panic, CTLTYPE_INT | CTLFLAG_RW, 0, 0, + kdb_sysctl_panic, "I", "set to panic the kernel"); + +SYSCTL_PROC(_debug_kdb, OID_AUTO, trap, CTLTYPE_INT | CTLFLAG_RW, 0, 0, + kdb_sysctl_trap, "I", "set cause a page fault"); + /* * Flag indicating whether or not to IPI the other CPUs to stop them on * entering the debugger. Sometimes, this will result in a deadlock as @@ -158,6 +166,38 @@ kdb_sysctl_enter(SYSCTL_HANDLER_ARGS) return (0); } +static int +kdb_sysctl_panic(SYSCTL_HANDLER_ARGS) +{ + int error, i; + + error = sysctl_wire_old_buffer(req, sizeof(int)); + if (error == 0) { + i = 0; + error = sysctl_handle_int(oidp, &i, 0, req); + } + if (error != 0 || req->newptr == NULL) + return (error); + panic("kdb_sysctl_panic"); + return (0); +} + +static int +kdb_sysctl_trap(SYSCTL_HANDLER_ARGS) +{ + int error, i; + int *addr = (int *)0x10; + + error = sysctl_wire_old_buffer(req, sizeof(int)); + if (error == 0) { + i = 0; + error = sysctl_handle_int(oidp, &i, 0, req); + } + if (error != 0 || req->newptr == NULL) + return (error); + return (*addr); +} + /* * Solaris implements a new BREAK which is initiated by a character sequence * CR ~ ^b which is similar to a familiar pattern used on Sun servers by the -- cgit v1.1