diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index c5d3f1b04c9c..5bb13a0cfeb5 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3601,30 +3601,67 @@ do {								\
 #define EXT4_FREECLUSTERS_WATERMARK 0
 #endif
 
-/* Update i_disksize. Requires i_rwsem to avoid races with truncate */
+/*
+ * Update i_disksize. Requires i_rwsem to avoid races with truncate.
+ *
+ * In the iomap buffered I/O path, the EXT4_STATE_DISKSIZE_GROW_PENDING
+ * inode state bit indicates that the zeroed EOF partial block which
+ * straddles i_disksize is still waiting writeback.  In that case,
+ * i_disksize will be updated after the pending zeroed data has been
+ * written out.
+ */
 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
 {
 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
 		     !inode_is_locked(inode));
 	down_write(&EXT4_I(inode)->i_data_sem);
-	if (newsize > EXT4_I(inode)->i_disksize)
+	if (newsize > EXT4_I(inode)->i_disksize &&
+	    !ext4_test_inode_state(inode, EXT4_STATE_DISKSIZE_GROW_PENDING))
 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
 	up_write(&EXT4_I(inode)->i_data_sem);
 }
 
-/* Update i_size, i_disksize. Requires i_rwsem to avoid races with truncate */
+static inline void __ext4_set_i_disksize(struct inode *inode, loff_t newsize)
+{
+	WARN_ON_ONCE(!rwsem_is_locked(&EXT4_I(inode)->i_data_sem));
+
+	if (newsize < EXT4_I(inode)->i_disksize ||
+	    !ext4_test_inode_state(inode, EXT4_STATE_DISKSIZE_GROW_PENDING))
+		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
+}
+
+/*
+ * Update i_size and i_disksize to @newsize.  Requires i_rwsem to avoid
+ * races with truncate.
+ *
+ * In the iomap buffered I/O path, i_disksize is updated only if no zeroed
+ * pending block straddles i_disksize (EXT4_STATE_DISKSIZE_GROW_PENDING
+ * clear), otherwise the ioend worker for the pending block will advance
+ * i_disksize once the pending block is written back.  Both updates happen
+ * under i_data_sem so that the writeback ioend worker can always see the
+ * latest i_size under the same semaphore.
+ *
+ * Returns 0 if nothing changed, 1 if i_size was raised, 2 if i_disksize
+ * was raised, or 3 if both were.
+ */
 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
 {
 	int changed = 0;
 
+	if (newsize <= inode->i_size && newsize <= EXT4_I(inode)->i_disksize)
+		return 0;
+
+	down_write(&EXT4_I(inode)->i_data_sem);
 	if (newsize > inode->i_size) {
 		i_size_write(inode, newsize);
 		changed = 1;
 	}
-	if (newsize > EXT4_I(inode)->i_disksize) {
-		ext4_update_i_disksize(inode, newsize);
+	if (newsize > EXT4_I(inode)->i_disksize &&
+	    !ext4_test_inode_state(inode, EXT4_STATE_DISKSIZE_GROW_PENDING)) {
+		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
 		changed |= 2;
 	}
+	up_write(&EXT4_I(inode)->i_data_sem);
 	return changed;
 }
 
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 30fa1ce09f0c..74e50716f6f4 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4561,7 +4561,7 @@ int ext4_ext_truncate(handle_t *handle, struct inode *inode)
 	 */
 
 	/* we have to know where to truncate from in crash case */
-	EXT4_I(inode)->i_disksize = inode->i_size;
+	__ext4_set_i_disksize(inode, inode->i_size);
 	err = ext4_mark_inode_dirty(handle, inode);
 	if (err)
 		return err;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index a271bb2550b0..e586d5eed3f0 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -6635,8 +6635,10 @@ static void ext4_wait_for_tail_page_commit(struct inode *inode)
  * Set i_size and i_disksize to 'newsize'.
  *
  * Both i_rwsem and i_data_sem are required here to avoid races between
- * generic append writeback and concurrent truncate that also modify
- * i_size and i_disksize.
+ * generic append writeback (or zeroed pending I/O writeback) and
+ * concurrent operations (e.g., fallocate, truncate) that also modify
+ * i_size and i_disksize. This also ensures that the writeback ioend worker
+ * observes the latest i_size under the same lock protection.
  */
 static inline void ext4_set_inode_size(struct inode *inode, loff_t newsize)
 {
@@ -6644,7 +6646,7 @@ static inline void ext4_set_inode_size(struct inode *inode, loff_t newsize)
 
 	down_write(&EXT4_I(inode)->i_data_sem);
 	i_size_write(inode, newsize);
-	EXT4_I(inode)->i_disksize = newsize;
+	__ext4_set_i_disksize(inode, newsize);
 	up_write(&EXT4_I(inode)->i_data_sem);
 }