On Fri, May 23, 2008 at 1:38 PM, Avi Nehori <[EMAIL PROTECTED]> wrote: > yes ,you are correct :) > seems like the debug registers are being set correctly(i have checked it and > debugged it ),but still the breakpoint does not > break.... > i have done a special testing ,i can tell you that if you will write the > memory address directly --- it will break. > but if you write the memory address indirectly ---- it will not break !!! What do you mean by "write the memory address indirectly"?
Regards Jason > > > > Jay Lan wrote: >> >> Avi Nehori wrote: >> >>> >>> Jay, >>> try to set an hardware breakpoint to a global variable and then modify >>> it . >>> the system will not drop into kdb in this case. >>> >> >> Hi Avi, >> >> I reprodued the problem. KDB hardware breakpoint is triggered on >> access to a function, but not on value changes to a global variable. >> It would be nice, isn't it? Hmmm... >> >> - jay >> >> >>> >>> Jay Lan wrote: >>> >>>> >>>> Avi Nehori wrote: >>>> >>>>> >>>>> Jay, >>>>> the patch didnt work for me. >>>>> I'm still looking for a resolution... >>>>> >>>> >>>> Hmmm, i just tested with Konstantin's patch on 2.6.25 and >>>> 2.6.26-rc3, and it seemed to work for me. >>>> >>>> >>>> >>>>> >>>>> Entering kdb (current=0xf7841c80, pid 0) on processor 1 due to Keyboard >>>>> Entry >>>>> >>>> >>>> [1]kdb> bpha do_sync >>>> Forced Instruction(Register) BP #0 at 0xc017b6a4 (do_sync) >>>> is enabled in dr0 globally >>>> [1]kdb> go >>>> >>>> I set up a global hardware breakpoint at do_sync here. >>>> Then i entered 'sync' command from a shell. The system dropped into KDB: >>>> >>>> Instruction(Register) breakpoint #0 at 0xc017b6a4 >>>> 0xc017b6a4 do_sync: push %ebx >>>> >>>> Entering kdb (0xf72a23a0, pid 5473) on processor 2 due to Debug @ >>>> 0xc017b6a4 >>>> [2]kdb> >>>> >>>> You are testing a 2.4.21 kernel... I do not know if KDB support i386 >>>> in 2.4.21 at all. >>>> >>>> Keith Owens did a tremendous job in making KDB backtrace working on >>>> x86_64/i386 and fixed other bugs along the way, but his work did not >>>> complete until 2.6.23. My brief effort of back porting the x86_64/i386 >>>> KDB support to sles10sp2 (2.6.16 based) and rhel5.2 (2.6.18 based) >>>> did not work well. So, honestly, i recommand you move up to 2.6.23 >>>> or later. >>>> >>>> Thanks, >>>> - jay >>>> >>>> >>>>> >>>>> Jay Lan wrote: >>>>> >>>>>> >>>>>> Hi Avi, >>>>>> >>>>>> Did Konstantin's patch work for you? His patch caused ia64 >>>>>> compilation to fail, but i would like to know if his patch >>>>>> work for you on i386. >>>>>> >>>>>> Thanks! >>>>>> >>>>>> - jay >>>>>> >>>>>> >>>>>> Scanned by Check Point Total Security Gateway. >>>>>> >>>>>> >>>>> >>>>> --------------------------- >>>>> Use http://oss.sgi.com/ecartis to modify your settings or to >>>>> unsubscribe. >>>>> >>>> >>>> Scanned by Check Point Total Security Gateway. >>>> >>>> >>> >>> --------------------------- >>> Use http://oss.sgi.com/ecartis to modify your settings or to unsubscribe. >>> >> >> >> Scanned by Check Point Total Security Gateway. >> >> > --------------------------- Use http://oss.sgi.com/ecartis to modify your settings or to unsubscribe.
