Update patch.py

Signed-off-by: elseif <elseif@live.cn>

patch.py

@@ -84,14 +84,23 @@ def patch_initrd_xz(initrd_xz:bytes,key_dict:dict,ljust=True):
         if old_public_key in new_initrd:
             print(f'initrd public key patched {old_public_key[:16].hex().upper()}...')
             new_initrd = new_initrd.replace(old_public_key,new_public_key)
-    new_initrd_xz = lzma.compress(new_initrd,check=lzma.CHECK_CRC32,filters=[{"id": lzma.FILTER_LZMA2, "preset": 9,}] )
+    preset = 6
+    new_initrd_xz = lzma.compress(new_initrd,check=lzma.CHECK_CRC32,filters=[{"id": lzma.FILTER_LZMA2, "preset": preset }] )
+    while len(new_initrd_xz) > len(initrd_xz):
+        print(f'preset:{preset}')
+        print(f'new initrd xz size:{len(new_initrd_xz)}')
+        print(f'old initrd xz size:{len(initrd_xz)}')
+        preset += 1
+        new_initrd_xz = lzma.compress(new_initrd,check=lzma.CHECK_CRC32,filters=[{"id": lzma.FILTER_LZMA2, "preset": preset }] )
+    if len(new_initrd_xz) > len(initrd_xz):
+        new_initrd_xz = lzma.compress(new_initrd,check=lzma.CHECK_CRC32,filters=[{"id": lzma.FILTER_LZMA2, "preset": 9 ,"mf": lzma.MF_BT2}] )
     if ljust:
-        assert len(new_initrd_xz) <= len(initrd_xz),'new initrd xz size is too big'
+        print(f'preset:{preset}')
         print(f'new initrd xz size:{len(new_initrd_xz)}')
         print(f'old initrd xz size:{len(initrd_xz)}')
         print(f'ljust size:{len(initrd_xz)-len(new_initrd_xz)}')
+        assert len(new_initrd_xz) <= len(initrd_xz),'new initrd xz size is too big'
         new_initrd_xz = new_initrd_xz.ljust(len(initrd_xz),b'\0')
-    return new_initrd_xz
 
 def find_7zXZ_data(data:bytes):
     offset1 = 0