>>> On 5/31/2016 at 12:10 AM, in message <alpine.DEB.2.10.1605301705170.3896@sstabellini-ThinkPad-X260>, Stefano Stabellini <sstabell...@kernel.org> wrote: > On Fri, 29 Apr 2016, Chunyan Liu wrote: > > Since commit a1666142: acpi-build: make ROMs RAM blocks resizeable, > > xen HVM direct kernel boot failed. Xen HVM direct kernel boot will > > insert a linuxboot.bin or multiboot.bin to /genroms, before this > > commit, in acpi_setup, for rom linuxboot.bin/multiboot.bin, it > > only needs 0x20000 size; after the commit, it will reserve x16 > > size for resize, that is 0x200000 size. It causes xen_ram_alloc > > failed due to running out of memory. > > > > To resolve it, either: > > 1. keep using original rom size instead of max size, don't reserve x16 > size. > > 2. guest maxmem needs to be increased. (commit c1d322e6 "xen-hvm: increase > > maxmem before calling xc_domain_populate_physmap" solved the problem for > > a time, by accident. But then it is reverted in commit ffffbb369 due to > > other problem.) > > > > For 2, more discussion is needed about howto. So this patch tries 1, to > > use unresizable rom size in xen case in rom_set_mr. > > > > Signed-off-by: Chunyan Liu <cy...@suse.com> > > Thank you for the patch! > > > > hw/core/loader.c | 6 +++++- > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > diff --git a/hw/core/loader.c b/hw/core/loader.c > > index c049957..5150101 100644 > > --- a/hw/core/loader.c > > +++ b/hw/core/loader.c > > @@ -55,6 +55,7 @@ > > #include "exec/address-spaces.h" > > #include "hw/boards.h" > > #include "qemu/cutils.h" > > +#include "hw/xen/xen.h" > > > > #include <zlib.h> > > > > @@ -818,7 +819,10 @@ static void *rom_set_mr(Rom *rom, Object *owner, const > > > char *name) > > void *data; > > > > rom->mr = g_malloc(sizeof(*rom->mr)); > > - memory_region_init_resizeable_ram(rom->mr, owner, name, > > + if (xen_enabled()) > > + memory_region_init_ram(rom->mr, owner, name, rom->datasize, > &error_fatal); > > + else > > + memory_region_init_resizeable_ram(rom->mr, owner, name, > > rom->datasize, rom->romsize, > > fw_cfg_resized, > > &error_fatal); > > Wouldn't it be better to change ram_block_add so that it calls > xen_ram_alloc with used_length rather than max_length?
Seems that's right. But after that changes, when doing direct kernel boot, it reports: qemu-system-x86_64: /home/cyliu/git/qemu/include/exec/ram_addr.h:48: ramblock_ptr: Assertion `offset_in_ramblock(block, offset)' failed. Looking at it. Chunyan > > I think that on Xen we want to only allocate used_length bytes, but > reserve max_length of address space. > > >
