arm (qemu -M virt) 64 bit xen running 32 bit guest problem

[Charles Chiou <cchiou@xxxxxxxxxxxxx>]

Hello,

I'm having problem with virtual console when booting up 32 bit guests. I'm 
using qemu virt machine, running xen 64 bit, DOM0 Linux is 64 bit. The 64 bit 
guests that I've tried (Linux, an RTOS) have no issues, but when I tried to run 
32 bit OS (tried linux, FreeRTOS from Galois, a bare-metal app), I get "Invalid 
MFN 0x33a08" or similar messages when making HVC calls such as:

        mov     r0, #0
        mov     r1, #35
        ldr     r2, =banner
        mov     r12, #18
        hvc     #0xea1<----

and get this at the HVC call to XEN:

(XEN) p2m.c:1919: d8v0: Invalid MFN 0x33a08

Not sure if there's misconfiguration somewhere, or compile options, etc. that 
caused this... Any pointer is greatly appreciated!

Below is output of similar problem when booting up a 32 bit linux kernel:

/ # xl -v create -c /share/misc/linux32.cfg
Parsing config from /share/misc/linux32.cfg
libxl: info: libxl_create.c:122:libxl__domain_build_info_setdefault: qemu-xen 
is unavailable, using qemu-xen-traditional instead: No such file or directory
libxl: detail: libxl_create.c:623:libxl__domain_make: passthrough: disabled
domainbuilder: detail: xc_dom_allocate: cmdline="rw root=/dev/ram 
rdinit=/sbin/init earlyprintk=serial,ttyAMA0", features=""
domainbuilder: detail: xc_dom_kernel_file: 
filename="/share/linux-domu-32bit/arch/arm/boot/zImage"
domainbuilder: detail: xc_dom_malloc_filemap    : 5904 kB
domainbuilder: detail: xc_dom_module_file: filename="/share/dom0-rootfs.img.gz"
domainbuilder: detail: xc_dom_malloc_filemap    : 13553 kB
domainbuilder: detail: xc_dom_boot_xen_init: ver 4.15, caps xen-3.0-aarch64 
xen-3.0-armv7l
domainbuilder: detail: xc_dom_rambase_init: RAM starts at 40000
domainbuilder: detail: xc_dom_parse_image: called
domainbuilder: detail: xc_dom_find_loader: trying multiboot-binary loader ...
domainbuilder: detail: loader probe failed
domainbuilder: detail: xc_dom_find_loader: trying Linux zImage (ARM64) loader 
...
domainbuilder: detail: xc_dom_probe_zimage64_kernel: kernel is not an arm64 
Image
domainbuilder: detail: loader probe failed
domainbuilder: detail: xc_dom_find_loader: trying Linux zImage (ARM32) loader 
...
domainbuilder: detail: loader probe OK
domainbuilder: detail: xc_dom_parse_zimage32_kernel: called
domainbuilder: detail: xc_dom_parse_zimage32_kernel: xen-3.0-armv7l: 0x40008000 
-> 0x405cc200
domainbuilder: detail: xc_dom_devicetree_mem: called
domainbuilder: detail: xc_dom_mem_init: mem 128 MB, pages 0x8000 pages, 4k each
domainbuilder: detail: xc_dom_mem_init: 0x8000 pages
domainbuilder: detail: xc_dom_boot_mem_init: called
domainbuilder: detail: set_mode: guest xen-3.0-armv7l, address size 32
domainbuilder: detail: populate_guest_memory: populating RAM @ 
0000000040000000-0000000048000000 (128MB)
domainbuilder: detail: populate_one_size: populated 0x40/0x40 entries with 
shift 9
domainbuilder: detail: meminit: placing boot modules at 0x472c2000
domainbuilder: detail: meminit: ramdisk: 0x472c2000 -> 0x47fff000
domainbuilder: detail: meminit: devicetree: 0x47fff000 -> 0x48000000
domainbuilder: detail: xc_dom_build_image: called
domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 
0x40008+0x5c5 at 0xffff93aea000
domainbuilder: detail: xc_dom_alloc_segment:   kernel       : 0x40008000 -> 
0x405cd000  (pfn 0x40008 + 0x5c5 pages)
domainbuilder: detail: xc_dom_load_zimage_kernel: called
domainbuilder: detail: xc_dom_load_zimage_kernel: kernel seg 
0x40008000-0x405cd000
domainbuilder: detail: xc_dom_load_zimage_kernel: copy 6046208 bytes from blob 
0xffff94dec000 to dst 0xffff93aea000
domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 
0x472c2+0xd3d at 0xffff92dad000
domainbuilder: detail: xc_dom_alloc_segment:   module0      : 0x472c2000 -> 
0x47fff000  (pfn 0x472c2 + 0xd3d pages)
domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 
0x47fff+0x1 at 0xffff95847000
domainbuilder: detail: xc_dom_alloc_segment:   devicetree   : 0x47fff000 -> 
0x48000000  (pfn 0x47fff + 0x1 pages)
domainbuilder: detail: alloc_magic_pages: called
domainbuilder: detail: xc_dom_build_image  : virt_alloc_end : 0x48000000
domainbuilder: detail: xc_dom_build_image  : virt_pgtab_end : 0x0
domainbuilder: detail: xc_dom_boot_image: called
domainbuilder: detail: bootearly: doing nothing
domainbuilder: detail: xc_dom_compat_check: supported guest type: 
xen-3.0-aarch64
domainbuilder: detail: xc_dom_compat_check: supported guest type: 
xen-3.0-armv7l <= matches
domainbuilder: detail: start_info_arm: called
domainbuilder: detail: domain builder memory footprint
domainbuilder: detail:    allocated
domainbuilder: detail:       malloc             : 117 kB
domainbuilder: detail:       anon mmap          : 0 bytes
domainbuilder: detail:    mapped
domainbuilder: detail:       file mmap          : 19457 kB
domainbuilder: detail:       domU mmap          : 19468 kB
domainbuilder: detail: vcpu_arm32: called
domainbuilder: detail: Initial state CPSR 0x1d3 PC 0x40008000
domainbuilder: detail: compat_gnttab_hvm_seed: d7: pfn=0x38000
domainbuilder: detail: xc_dom_set_gnttab_entry: d7 gnt[0] -> d0 0x39000
domainbuilder: detail: xc_dom_set_gnttab_entry: d7 gnt[1] -> d0 0x39001
domainbuilder: detail: xc_dom_release: called
(XEN) p2m.c:1919: d7v0: Invalid MFN 0x3b401
(XEN) d7v0: vGICR: SGI: unhandled word write 0x000000ffffffff to ICACTIVER0
(XEN) p2m.c:1919: d7v0: Invalid MFN 0x3b401
(XEN) p2m.c:1919: d7v0: Invalid MFN 0x39281

--
Charles Chiou
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