On Thu, 13 Nov 2014 09:17:09 +0900 (JST) HATAYAMA Daisuke <d.hatayama at jp.fujitsu.com> wrote: > From: Vivek Goyal <vgoyal at redhat.com> > Subject: Re: [PATCH] kdump, x86: report actual value of phys_base in VMCOREINFO > Date: Wed, 12 Nov 2014 17:12:05 -0500 > > > On Wed, Nov 12, 2014 at 03:40:42PM +0900, HATAYAMA Daisuke wrote: > >> Currently, VMCOREINFO note information reports the virtual address of > >> phys_base that is assigned to symbol phys_base. But this doesn't make > >> sense because to refer to value of the phys_base, it's necessary to > >> get the value of phys_base itself we are now about to refer to. > >> > > > > Hi Hatayama, > > > > /proc/vmcore ELF headers have virtual address information and using > > that you should be able to read actual value of phys_base. gdb deals > > with virtual addresses all the time and can read value of any symbol > > using those headers. > > > > So I am not sure what's the need for exporting actual value of > > phys_base. > > > > Sorry, my logic in the patch description was wrong. For /proc/vmcore, > there's enough information for makedumpdile to get phys_base. It's > correct. The problem here is that other crash dump mechanisms that run > outside Linux kernel independently don't have information to get > phys_base. Yes, but these mechanisms won't be able to read VMCOREINFO either, will they? Petr T
