diff --git a/alioth/src/firmware/dt/dtb.rs b/alioth/src/firmware/dt/dtb.rs
index 6f60f1a..a205fef 100644
--- a/alioth/src/firmware/dt/dtb.rs
+++ b/alioth/src/firmware/dt/dtb.rs
@@ -33,14 +33,14 @@ pub const FDT_END: [u8; 4] = [0x00, 0x00, 0x00, 0x09];
 
 fn push_string_align(data: &mut Vec<u8>, s: &str) {
     data.extend(s.as_bytes());
-    let padding = align_up!(s.len() + 1, 4) - s.len();
+    let padding = align_up!(s.len() + 1, 2) - s.len();
     for _ in 0..padding {
         data.push(b'\0');
     }
 }
 
 fn pad_data(data: &mut Vec<u8>) {
-    let padding = align_up!(data.len(), 4) - data.len();
+    let padding = align_up!(data.len(), 2) - data.len();
     for _ in 0..padding {
         data.push(b'\0');
     }
diff --git a/alioth/src/loader/xen/xen.rs b/alioth/src/loader/xen/xen.rs
index f74c656..d59957a 100644
--- a/alioth/src/loader/xen/xen.rs
+++ b/alioth/src/loader/xen/xen.rs
@@ -57,19 +57,20 @@ fn search_pvh_note<F: Read + Seek>(
     size: u64,
     align: u64,
 ) -> std::io::Result<Option<u64>> {
+    let align_bits = std::cmp::max(align, 1).trailing_zeros();
     let mut pos = 0;
     while pos < size {
         file.seek(SeekFrom::Start(offset + pos))?;
         let mut header = Elf64Note::new_zeroed();
         file.read_exact(header.as_mut_bytes())?;
         pos += size_of::<Elf64Note>() as u64;
-        pos += align_up!(header.desc_sz as u64, align);
-        pos += align_up!(header.name_sz as u64, align);
+        pos += align_up!(header.desc_sz as u64, align_bits);
+        pos += align_up!(header.name_sz as u64, align_bits);
         if header.type_ != XEN_ELFNOTE_PHYS32_ENTRY {
             continue;
         }
         file.seek(SeekFrom::Current(
-            align_up!(header.name_sz as u64, align) as i64
+            align_up!(header.name_sz as u64, align_bits) as i64,
         ))?;
         match header.desc_sz {
             4 => {
diff --git a/alioth/src/pci/bus.rs b/alioth/src/pci/bus.rs
index dac1631..ce6b17e 100644
--- a/alioth/src/pci/bus.rs
+++ b/alioth/src/pci/bus.rs
@@ -179,7 +179,7 @@ impl PciBus {
             for (bdf, dev, index, size) in bar_list {
                 let config = dev.dev.config();
                 let mut header = config.get_header().data.write();
-                let aligned_addr = align_up!(addr, size);
+                let aligned_addr = align_up!(addr, size.trailing_zeros());
                 if aligned_addr + size > *end {
                     log::error!(
                         "{bdf}: cannot map BAR {index} into address range {start:#x}..{end:#x}"
diff --git a/alioth/src/pci/cap.rs b/alioth/src/pci/cap.rs
index e9d3520..35d7ca7 100644
--- a/alioth/src/pci/cap.rs
+++ b/alioth/src/pci/cap.rs
@@ -203,7 +203,7 @@ impl TryFrom<Vec<Box<dyn PciCap>>> for PciCapList {
             let next = if index == num_caps - 1 {
                 0
             } else {
-                align_up!(ptr + Mmio::size(&cap), 4)
+                align_up!(ptr + Mmio::size(&cap), 2)
             };
             cap.set_next(next as u8);
             bus.add(ptr, cap)?;
diff --git a/alioth/src/utils/utils.rs b/alioth/src/utils/utils.rs
index 8a7ffe6..31d869b 100644
--- a/alioth/src/utils/utils.rs
+++ b/alioth/src/utils/utils.rs
@@ -20,18 +20,16 @@ pub mod ioctls;
 
 #[macro_export]
 macro_rules! align_up {
-    ($num:expr, $align:expr) => {{
-        debug_assert_eq!(($align as u64).count_ones(), 1);
-        let mask = $align - 1;
+    ($num:expr, $bits:expr) => {{
+        let mask = (1 << $bits) - 1;
         ($num.wrapping_add(mask)) & !mask
     }};
 }
 
 #[macro_export]
 macro_rules! align_down {
-    ($num:expr, $align:expr) => {{
-        debug_assert_eq!(($align as u64).count_ones(), 1);
-        let mask = $align - 1;
+    ($num:expr, $bits:expr) => {{
+        let mask = (1 << $bits) - 1;
         $num & !mask
     }};
 }
@@ -176,17 +174,11 @@ macro_rules! c_enum {
 mod test {
     #[test]
     fn test_align_up() {
-        assert_eq!(align_up!(0u64, 4), 0);
-        assert_eq!(align_up!(1u64, 4), 4);
-        assert_eq!(align_up!(3u64, 4), 4);
+        assert_eq!(align_up!(0u64, 2), 0);
+        assert_eq!(align_up!(1u64, 2), 4);
+        assert_eq!(align_up!(3u64, 2), 4);
 
-        assert_eq!(align_up!(u64::MAX, 1), u64::MAX);
-        assert_eq!(align_up!(u64::MAX, 4), 0);
-    }
-
-    #[test]
-    #[should_panic]
-    fn test_align_up_panic() {
-        let _ = align_up!(1u64, 3);
+        assert_eq!(align_up!(u64::MAX, 0), u64::MAX);
+        assert_eq!(align_up!(u64::MAX, 2), 0);
     }
 }
diff --git a/alioth/src/vfio/pci.rs b/alioth/src/vfio/pci.rs
index fd13c0a..626c6c6 100644
--- a/alioth/src/vfio/pci.rs
+++ b/alioth/src/vfio/pci.rs
@@ -48,7 +48,7 @@ use crate::vfio::{error, Result, VfioParam};
 use crate::{align_down, align_up, assign_bits, mask_bits, mem};
 
 fn round_up_range(range: Range<usize>) -> Range<usize> {
-    (align_down!(range.start, 0x1000))..(align_up!(range.end, 0x1000))
+    (align_down!(range.start, 12))..(align_up!(range.end, 12))
 }
 
 fn create_mapped_bar_pages(
@@ -177,7 +177,7 @@ where
     let table_offset = msix_table_offset.0 as usize & !0b111;
     let pba_offset = msix_pba_offset.0 as usize & !0b111;
     let table_range = table_offset..(table_offset + size_of::<MsixTableEntry>() * num_msix_entries);
-    let pba_range = pba_offset..(pba_offset + (align_up!(num_msix_entries, 64) >> 3));
+    let pba_range = pba_offset..(pba_offset + (align_up!(num_msix_entries, 6) >> 3));
 
     if msix_table_offset.bar() == index && msix_pba_offset.bar() == index {
         create_splitted_bar_region(
diff --git a/alioth/src/virtio/dev/fs.rs b/alioth/src/virtio/dev/fs.rs
index 740e34e..2d8ce22 100644
--- a/alioth/src/virtio/dev/fs.rs
+++ b/alioth/src/virtio/dev/fs.rs
@@ -139,7 +139,7 @@ impl VuFs {
         };
         let dax_region = if param.dax_window > 0 {
             vu_dev.setup_channel()?;
-            let size = align_up!(param.dax_window, 4 << 10);
+            let size = align_up!(param.dax_window, 12);
             Some(ArcMemPages::from_anonymous(size, Some(PROT_NONE), None)?)
         } else {
             None