Hello Derek, I remember that SysRq is activated either of following 2 actions, 1) SysRq-G key sequence on keyboard and 2) BREAK g from serial port. 1) is obvious. 2) may be from console. I don't remember. But with the options I assigned for kernel invocation which is difference than yours, I can break-in. Thank you for the report. -caz
-----Original Message----- From: Derek Atkins [mailto:[email protected]] Sent: Thursday, April 30, 2009 7:48 AM To: Caz Yokoyama Cc: [email protected] Subject: RE: [Kgdb-bugreport] debugging kernel modules with kgdb-light in2.6.29.1 I'm not sure what you mean by "share my operation". But as I pointed out in mail yesterday, I run the kernel with: kgdb8250=ttyS0,115200 kgdbcon kgdbwait I can connect fine at the start. Then I run 'c' to continue in GDB. Then I hit Ctrl-C and get: (gdb) c Continuing. ^C^CInterrupted while waiting for the program. Give up (and stop debugging it)? (y or n) n SysRq : SysRq : GDB [New Thread -2] Program received signal SIGTRAP, Trace/breakpoint trap. [Switching to Thread -2] sysrq_handle_gdb (key=103, tty=0xde338400) at kernel/kgdb.c:1804 1804 wmb(); /* Sync point after breakpoint */ In other words, the Ctrl-C did not interrupt the kernel.. I had to go over to the console and hit the SysRq-G key sequence (which is really damn hard, by the way!) in order to get back into GDB. -derek Quoting Caz Yokoyama <[email protected]>: > Hello Derek, > How inconsistent? I have never experienced inconsistency with 2.6.27. Once > the connection between gdb and a target is established, gdb simply transmits > BREAK and g when debugkernel is true. When Magic SysReq is enabled on target > Linux kernel, Linux kernel breaks-in and gives control to gdb. Are you able > to share your operation? > -caz > > -----Original Message----- > From: Derek Atkins [mailto:[email protected]] > Sent: Thursday, April 30, 2009 7:11 AM > To: Caz Yokoyama > Cc: 'Dmitry Mikhin'; [email protected] > Subject: Re: [Kgdb-bugreport] debugging kernel modules with kgdb-light in > 2.6.29.1 > > Caz Yokoyama <[email protected]> writes: > >> Hello Dmitry, >> I'm glad to hear that you can refer symbols of loadable modules. Have you >> typed ^C and broke-in when a target is running? > > I have tried but it's inconsistent about whether this works (using > 2.6.27 and your gdb-6.8-kgdblight) > > -derek > > -- > Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory > Member, MIT Student Information Processing Board (SIPB) > URL: http://web.mit.edu/warlord/ PP-ASEL-IA N1NWH > [email protected] PGP key available > > -- Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory Member, MIT Student Information Processing Board (SIPB) URL: http://web.mit.edu/warlord/ PP-ASEL-IA N1NWH [email protected] PGP key available ------------------------------------------------------------------------------ Register Now & Save for Velocity, the Web Performance & Operations Conference from O'Reilly Media. Velocity features a full day of expert-led, hands-on workshops and two days of sessions from industry leaders in dedicated Performance & Operations tracks. Use code vel09scf and Save an extra 15% before 5/3. http://p.sf.net/sfu/velocityconf _______________________________________________ Kgdb-bugreport mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport
