Hi Luca, On 10/05/2024 11:25, Luca Fancellu wrote: > > >> On 10 May 2024, at 10:17, Michal Orzel <michal.or...@amd.com> wrote: >> >> Hi Luca, >> >> On 23/04/2024 10:25, Luca Fancellu wrote: >>> >>> >>> This commit implements the logic to have the static shared memory banks >>> from the Xen heap instead of having the host physical address passed from >>> the user. >>> >>> When the host physical address is not supplied, the physical memory is >>> taken from the Xen heap using allocate_domheap_memory, the allocation >>> needs to occur at the first handled DT node and the allocated banks >>> need to be saved somewhere, so introduce the 'shm_heap_banks' static >>> global variable of type 'struct meminfo' that will hold the banks >>> allocated from the heap, its field .shmem_extra will be used to point >>> to the bootinfo shared memory banks .shmem_extra space, so that there >>> is not further allocation of memory and every bank in shm_heap_banks >>> can be safely identified by the shm_id to reconstruct its traceability >>> and if it was allocated or not. >>> >>> A search into 'shm_heap_banks' will reveal if the banks were allocated >>> or not, in case the host address is not passed, and the callback given >>> to allocate_domheap_memory will store the banks in the structure and >>> map them to the current domain, to do that, some changes to >>> acquire_shared_memory_bank are made to let it differentiate if the bank >>> is from the heap and if it is, then assign_pages is called for every >>> bank. >>> >>> When the bank is already allocated, for every bank allocated with the >>> corresponding shm_id, handle_shared_mem_bank is called and the mapping >>> are done. >>> >>> Signed-off-by: Luca Fancellu <luca.fance...@arm.com> >> >> I tested this patch and it resulted in assertion: >> Assertion 's <= e' failed at common/rangeset.c:189 >> >> I checked and in find_unallocated_memory(), given that start is ~0UL (host >> address not provided), >> start + size would overflow. Did you test this patch? > > Hi Michal, > > Mmm I’m testing with a dom0less setup, without dom0, I think I missed that > part because my guests doesn’t have > the hypervisor node (enhanced), sorry about that, I’ll test using your setup, > can you confirm what are you using? I have these Qemu tests (with and without SMMU): - shmem between domU1 and domU2 with/without host address provided (owner domIO or domU1) - shmem between dom0 and domU1 with/without host address provided (owner domIO or dom0)
BTW. What was the conclusion about the issue if shmem region clashes with RAM allocated for 1:1 domU e.g. dom0. Accidentally, I end up with a configuration where Xen allocated for dom0 a region of RAM clashing with my shmem region. ~Michal
