From 1370d61ae3c9934861d2349349447605202f04e9 Mon Sep 17 00:00:00 2001 From: Zenghui Yu Date: Mon, 16 Nov 2020 21:22:10 +0800 Subject: [PATCH] memory: Skip dirty tracking for un-migratable memory regions It makes no sense to track dirty pages for those un-migratable memory regions (e.g., Memory BAR region of the VFIO PCI device) and doing so will potentially lead to some unpleasant issues during migration [1]. Skip dirty tracking for those regions by evaluating if the region is migratable before setting dirty_log_mask (DIRTY_MEMORY_MIGRATION). [1] https://lists.gnu.org/archive/html/qemu-devel/2020-11/msg03757.html Signed-off-by: Zenghui Yu Message-Id: <20201116132210.1730-1-yuzenghui@huawei.com> Reviewed-by: Cornelia Huck Signed-off-by: Paolo Bonzini --- softmmu/memory.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/softmmu/memory.c b/softmmu/memory.c index 71951fe4dc..aa393f1bb0 100644 --- a/softmmu/memory.c +++ b/softmmu/memory.c @@ -1806,7 +1806,10 @@ bool memory_region_is_ram_device(MemoryRegion *mr) uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr) { uint8_t mask = mr->dirty_log_mask; - if (global_dirty_log && (mr->ram_block || memory_region_is_iommu(mr))) { + RAMBlock *rb = mr->ram_block; + + if (global_dirty_log && ((rb && qemu_ram_is_migratable(rb)) || + memory_region_is_iommu(mr))) { mask |= (1 << DIRTY_MEMORY_MIGRATION); } return mask;