Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 253c9240 authored by Ming Lei's avatar Ming Lei Committed by Greg Kroah-Hartman
Browse files

firmware loader: fix one reqeust_firmware race 



Several loading requests may be pending on one same
firmware buf, and this patch moves fw_map_pages_buf()
before complete_all(&fw_buf->completion) and let all
requests see the mapped 'buf->data' once the loading
is completed.

Signed-off-by: default avatarMing Lei <ming.lei@canonical.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 373304fe

drivers/base/firmware_class.c

+20 −12
Original line number Diff line number Diff line
@@ -423,6 +423,18 @@ static void firmware_free_data(const struct firmware *fw) 
#ifndef PAGE_KERNEL_RO

#define PAGE_KERNEL_RO PAGE_KERNEL

#endif



/* one pages buffer should be mapped/unmapped only once */

static int fw_map_pages_buf(struct firmware_buf *buf)

{

	if (buf->data)

		vunmap(buf->data);

	buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);

	if (!buf->data)

		return -ENOMEM;

	return 0;

}



/**

 * firmware_loading_store - set value in the 'loading' control file

 * @dev: device pointer
@@ -467,6 +479,14 @@ static ssize_t firmware_loading_store(struct device *dev, 
		if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {

			set_bit(FW_STATUS_DONE, &fw_buf->status);

			clear_bit(FW_STATUS_LOADING, &fw_buf->status);



			/*

			 * Several loading requests may be pending on

			 * one same firmware buf, so let all requests

			 * see the mapped 'buf->data' once the loading

			 * is completed.

			 * */

			fw_map_pages_buf(fw_buf);

			complete_all(&fw_buf->completion);

			break;

		}
@@ -670,15 +690,6 @@ exit: 
	return fw_priv;

}



/* one pages buffer is mapped/unmapped only once */

static int fw_map_pages_buf(struct firmware_buf *buf)

{

	buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);

	if (!buf->data)

		return -ENOMEM;

	return 0;

}



/* store the pages buffer info firmware from buf */

static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)

{
@@ -884,9 +895,6 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent, 
	if (!retval && f_dev->parent)

		fw_add_devm_name(f_dev->parent, buf->fw_id);



	if (!retval)

		retval = fw_map_pages_buf(buf);



	/*

	 * After caching firmware image is started, let it piggyback

	 * on request firmware.