On Wed, 29 Jul 2020 03:17:39 +0200,
Luis Chamberlain wrote:

Long ago Takashi had some points about this strategy breaking
compressed file use. Was that considered?

As long as I read the patch, it tries to skip both the compressed and
the fallback loading when FW_OPT_PARTIAL is set, which is good.

However...

quoted

@@ -771,18 +805,20 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
 	}
 
 	ret = _request_firmware_prepare(&fw, name, device, buf, size,
-					opt_flags);
+					offset, opt_flags);
 	if (ret <= 0) /* error or already assigned */
 		goto out;
 
 	ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
-#ifdef CONFIG_FW_LOADER_COMPRESS
-	if (ret == -ENOENT)
+
+	/* Only full reads can support decompression, platform, and sysfs. */
+	if (!(opt_flags & FW_OPT_PARTIAL))
+		nondirect = true;
+
+	if (ret == -ENOENT && nondirect)
 		ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
 						 fw_decompress_xz);
-#endif

... by dropping this ifdef, the fw loader would try to access *.xz
file unnecessarily even if CONFIG_FW_LOADER_COMPRESS is disabled.


thanks,

Takashi