On Wed, Jun 17, 2009 at 02:14:20PM +1000, David Gibson wrote: > On Wed, Jun 10, 2009 at 02:38:18PM +0530, K.Prasad wrote: > > Modify process handling code to recognise hardware debug registers during > > copy > > and flush operations. Introduce a new TIF_DEBUG task flag to indicate a > > process's use of debug register. Load the debug register values into a > > new CPU during initialisation. > > > > Signed-off-by: K.Prasad <pra...@linux.vnet.ibm.com> > > --- > > arch/powerpc/kernel/process.c | 15 +++++++++++++++ > > arch/powerpc/kernel/smp.c | 2 ++ > > 2 files changed, 17 insertions(+) > > > > Index: linux-2.6-tip.hbkpt/arch/powerpc/kernel/process.c > > =================================================================== > > --- linux-2.6-tip.hbkpt.orig/arch/powerpc/kernel/process.c > > +++ linux-2.6-tip.hbkpt/arch/powerpc/kernel/process.c > > @@ -50,6 +50,7 @@ > > #include <asm/syscalls.h> > > #ifdef CONFIG_PPC64 > > #include <asm/firmware.h> > > +#include <asm/hw_breakpoint.h> > > #endif > > #include <linux/kprobes.h> > > #include <linux/kdebug.h> > > @@ -254,8 +255,10 @@ void do_dabr(struct pt_regs *regs, unsig > > 11, SIGSEGV) == NOTIFY_STOP) > > return; > > > > +#ifndef CONFIG_PPC64 > > if (debugger_dabr_match(regs)) > > return; > > +#endif > > Won't this disable the check for breakpoints set by xmon - but I don't > see anything in this patch series to convert xmon to use the new > breakpoint interface instead. >
As noted by me here: http://lists.ozlabs.org/pipermail/linuxppc-dev/2009-May/071832.html the Xmon integration is pending. When I tried to study and integrate Xmon, I found that the HW Breakpoint triggering was broken as of 2.6.29 kernel (tested on a Power5 box). This would mean that if Xmon's hardware breakpoint infrastructure is used in tandem with the given breakpoint interfaces, they would conflict with each other resulting in difficult-to-predict behaviour (the last to grab the register will use it). I think that tidying up do_dabr() is best done along with Xmon integration. > -- > David Gibson | I'll have my music baroque, and my code > david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ > _other_ > | _way_ _around_! > http://www.ozlabs.org/~dgibson Thanks, K.Prasad _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
