diff --git a/fuzzers/qemu_systemmode/README.md b/fuzzers/qemu_systemmode/README.md
index db7321e014..14098dc09c 100644
--- a/fuzzers/qemu_systemmode/README.md
+++ b/fuzzers/qemu_systemmode/README.md
@@ -21,6 +21,6 @@ Create on and then run the fuzzer:
 # create an image
 qemu-img create -f qcow2 dummy.qcow2 32M
 # run the fuzzer
-KERNEL=./example/example.elf target/release/qemu_launcher -icount shift=auto,align=off,sleep=off -machine mps2-an385 -monitor null -kernel ./example/example.elf -serial null -nographic -snapshot -drive if=none,format=qcow2,file=dummy.qcow2 -S
+KERNEL=./example/example.elf target/release/qemu_systemmode -icount shift=auto,align=off,sleep=off -machine mps2-an385 -monitor null -kernel ./example/example.elf -serial null -nographic -snapshot -drive if=none,format=qcow2,file=dummy.qcow2 -S
 ```
 Currently the ``KERNEL`` variable is needed because the fuzzer does not parse QEMUs arguments to find the binary.
\ No newline at end of file
diff --git a/fuzzers/qemu_systemmode/src/fuzzer.rs b/fuzzers/qemu_systemmode/src/fuzzer.rs
index 65e98fc776..d7bf9f5910 100644
--- a/fuzzers/qemu_systemmode/src/fuzzer.rs
+++ b/fuzzers/qemu_systemmode/src/fuzzer.rs
@@ -36,20 +36,20 @@ use libafl_qemu::{
     edges::QemuEdgeCoverageHelper,
     elf::EasyElf,
     emu::Emulator,
+    GuestAddr,
     //snapshot::QemuSnapshotHelper,
     QemuExecutor,
     QemuHooks,
     Regs,
 };
 
-fn virt2phys(vaddr: u32, tab: &EasyElf) -> u32 {
+/// Read ELF program headers to resolve physical load addresses.
+fn virt2phys(vaddr: GuestAddr, tab: &EasyElf) -> GuestAddr {
     let ret;
     for i in &tab.goblin().program_headers {
-        if i.vm_range()
-            .contains(&vaddr.try_into().expect("Can not cast u64 to usize"))
-        {
-            ret = vaddr - TryInto::<u32>::try_into(i.p_vaddr).unwrap()
-                + TryInto::<u32>::try_into(i.p_paddr).unwrap();
+        if i.vm_range().contains(&vaddr.try_into().unwrap()) {
+            ret = vaddr - TryInto::<GuestAddr>::try_into(i.p_vaddr).unwrap()
+                + TryInto::<GuestAddr>::try_into(i.p_paddr).unwrap();
             return ret - (ret % 2);
         }
     }
@@ -113,7 +113,7 @@ pub fn fuzz() {
                     // len = MAX_INPUT_SIZE;
                 }
 
-                emu.write_mem(input_addr, buf);
+                emu.write_phys_mem(input_addr, buf);
 
                 emu.run();