[Xen-devel] incorrect layout of globals from head_64.S during kexec boot
olaf at aepfle.de
Fri Jul 6 09:31:05 EDT 2012
On Fri, Jul 06, Jan Beulich wrote:
> >>> On 06.07.12 at 14:07, Olaf Hering <olaf at aepfle.de> wrote:
> > But adding some debug to inspect
> > *output in parse_elf() shows that the second entry in program headers is
> > already shifted by 44 bytes in my testing, the others are shifted by the
> > same amount.
> Unfortunately it's not clear what is shifted - the printout below
> looks just fine. Also, from your first mail I understood that the shift
> there was by an amount not divisible by 4 - does that amount vary?
The memory location of the second LOAD entry (the .data section) is wrong.
It should be at 0x1c00000, but in fact its content starts at 0x1c0002c.
I looked at the x86 boot code, the vmlinux is gzipped and placed as
binary blob, which is then extracted by decompress().
I will cleanup my debug changes and post the output.
> > Program Headers:
> > Type Offset VirtAddr PhysAddr FileSiz
> > MemSiz Flg Align
> > LOAD 0x200000 0xffffffff81000000 0x0000000001000000 0xa3b000
> > 0xa3b000 R E 0x200000
> > LOAD 0xe00000 0xffffffff81c00000 0x0000000001c00000 0x05b0e8
> > 0x05b0e8 RW 0x200000
> > LOAD 0x1000000 0x0000000000000000 0x0000000001c5c000 0x012c40
> > 0x012c40 RW 0x200000
> > LOAD 0x106f000 0xffffffff81c6f000 0x0000000001c6f000 0x087000
> > 0x702000 RWE 0x200000
> > NOTE 0x82d5bc 0xffffffff8162d5bc 0x000000000162d5bc 0x00017c
> > 0x00017c 0x4
More information about the kexec