On Fri, Apr 10, 2015 at 03:29:56PM +0100, Peter Maydell wrote: > On 9 April 2015 at 04:47, Edgar E. Iglesias <edgar.igles...@gmail.com> wrote: > > On Sat, Apr 04, 2015 at 02:15:10PM +0200, Dirk Müller wrote: > >> Commit 0b183fc871:"memory: move mem_path handling to > >> memory_region_allocate_system_memory" split memory_region_init_ram and > >> memory_region_init_ram_from_file. Also it moved mem-path handling a step > >> up from memory_region_init_ram to memory_region_allocate_system_memory. > >> > >> Therefore for any board that uses memory_region_init_ram directly, > >> -mem-path is not supported. > >> > >> Fix this by replacing memory_region_init_ram with > >> memory_region_allocate_system_memory. > >> > >> Cc: Edgar E. Iglesias <edgar.igles...@gmail.com> > >> Signed-off-by: Dirk Mueller <dmuel...@suse.com> > >> --- > >> hw/cris/axis_dev88.c | 5 ++--- > >> 1 file changed, 2 insertions(+), 3 deletions(-) > > > > > > Hi, > > > > A question, should this only be done for one of the memories? > > Yes; as I understand it every board should call > memory_region_allocate_system_memory once and only once, > to allocate the "big lump" of RAM which should be backed by > the -mem-path memory (hugepages, etc). If a board's major > RAM is actually in two parts, you can deal with this by > calling memory_region_allocate_system_memory once to get > an MR with enough RAM for both parts, and then creating > alias MemoryRegions for each part which point into that. > [cf: https://lists.gnu.org/archive/html/qemu-devel/2015-03/msg05073.html] > > In the case of this cris board it looks to me from a > quick scan of the board init code like it has one big > lump of RAM (the one converted by this code) and then > a few smaller "internal ram" type things. So just doing > this for the big lump is correct. > > (The only use of -mem-path here is to allow the user to > cause us to back QEMU's guest RAM allocations with host > huge pages, which is in turn only something you care about > for KVM. So for the TCG-only CPUs and boards this is > to some extent academic, except it would be nice to be > able to enable an assert that the board init does call > memory_region_allocate_system_memory exactly once so we > can catch cases where we forgot for KVM-enabled archs.) >
I see, thanks for explaining. I gave a quick try with a CRIS image and it works fine. Tested-by: Edgar E. Iglesias <edgar.igles...@xilinx.com> Reviewed-by: Edgar E. Iglesias <edgar.igles...@xilinx.com> The patch has some kind of whitespace issue, but it applies with --ignore-whitespace. I've pushed it now, thanks! Cheers, Edgar
