From: Xiaoyao Li Date: Mon, 28 Jul 2025 11:57:07 +0000 (+0800) Subject: accel/kvm: Set guest_memfd_offset to non-zero value only when guest_memfd is valid X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=00c0911c68e5bd664de1a261b74c390f4c0be83d;p=thirdparty%2Fqemu.git accel/kvm: Set guest_memfd_offset to non-zero value only when guest_memfd is valid Current QEMU unconditionally sets the guest_memfd_offset of KVMSlot in kvm_set_phys_mem(), which leads to the trace of kvm_set_user_memory looks: kvm_set_user_memory AddrSpace#0 Slot#4 flags=0x2 gpa=0xe0000 size=0x20000 ua=0x7f5840de0000 guest_memfd=-1 guest_memfd_offset=0x3e0000 ret=0 It's confusing that the guest_memfd_offset has a non-zero value while the guest_memfd is invalid (-1). Change to only set guest_memfd_offset when guest_memfd is valid and leave it as 0 when no valid guest_memfd. Signed-off-by: Xiaoyao Li Link: https://lore.kernel.org/r/20250728115707.1374614-4-xiaoyao.li@intel.com Signed-off-by: Paolo Bonzini --- diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 72b571a6972..9060599cd73 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -1595,7 +1595,8 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml, mem->ram = ram; mem->flags = kvm_mem_flags(mr); mem->guest_memfd = mr->ram_block->guest_memfd; - mem->guest_memfd_offset = (uint8_t*)ram - mr->ram_block->host; + mem->guest_memfd_offset = mem->guest_memfd >= 0 ? + (uint8_t*)ram - mr->ram_block->host : 0; kvm_slot_init_dirty_bitmap(mem); err = kvm_set_user_memory_region(kml, mem, true);