[Qemu-devel] -initrd broken in latest CVS (+fix)

[Matthew Bloch]

I was wanting to use qemu (CVS as of earlier today) to test some kernel /
initrd boot combinations and found that the -initrd functionality was
broken:

checking if image is initramfs...it isn't (bad gzip magic numbers); looks
like an initrd
Freeing initrd memory: 8566k freed
Unable to handle kernel paging request at virtual address d10f9c1c
 printing eip:
c0137d31
*pde = 00000000
Oops: 0000 [#1]
PREEMPT SMP
Modules linked in:
CPU:    0
EIP:    0060:[<c0137d31>]    Not tainted VLI
EFLAGS: 00000093   (2.6.10-bytemark-i386-20050119-1)
EIP is at free_pages_bulk+0x12d/0x244
eax: 00000001   ebx: c0353d04   ecx: c0353d88   edx: c1100180
esi: fff9a9e7   edi: 7ffcd4f3   ebp: 00000000   esp: c11abf50
ds: 007b   es: 007b   ss: 0068
Process swapper (pid: 1, threadinfo=c11aa000 task=c119aa20)
Stack: 00000001 c0353d88 c1008c00 00000001 ffffffff c0353d04 c0353d00
00000000
       c1000000 c0353d04 00000086 c0353880 c1008ce0 c11aa000 c0353910
c0138335
       c0353880 00000000 c0353910 00000000 00000282 c0353880 c0468000
c0c5d800
Call Trace:
 [<c0138335>] free_hot_cold_page+0x115/0x120
 [<c01138b5>] free_initrd_mem+0x5d/0x6c
 [<c03e1b38>] populate_rootfs+0xa8/0xd8
 [<c01004b3>] init+0x73/0x160
 [<c0100440>] init+0x0/0x160
 [<c010123d>] kernel_thread_helper+0x5/0xc
Code: 03 83 fd 09 0f 87 af 00 00 00 8d 93 08 05 00 00 89 54 24 04 89 f6 8b
4c 24 04 39 4c 24 14 0f 83 00 01 00 00 8b 5c 24 14 8b 53 08 <0f> bb 3a 19
c0 85 c0 0f 84 81 00 00 00 89 e9 b8 01 00 00 00 d3
 <0>Kernel panic - not syncing: Attempted to kill init!

I'm not entirely sure what the issue was but in hw/pc.c changing

#define INITRD_LOAD_ADDR     0x00400000

to:

#define INITRD_LOAD_ADDR     0x00600000

seemed to fix it-- I support the kernel was stomping over the initrd and
putting it a bit higher in memory seemed to fix this.

-- 
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