Commit 1b29c164 authored by Vivek Goyal's avatar Vivek Goyal Committed by Andi Kleen
Browse files

[PATCH] x86-64: do not use virt_to_page on kernel data address 



o virt_to_page() call should be used on kernel linear addresses and not
  on kernel text and data addresses. Swsusp code uses it on kernel data
  (statically allocated swsusp_header).

o Allocate swsusp_header dynamically so that virt_to_page() can be used
  safely.

o I am changing this because in next few patches, __pa() on x86_64 will
  no longer support kernel text and data addresses and hibernation breaks.

Signed-off-by: default avatarVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: default avatarAndi Kleen <ak@suse.de>
parent 49c3df6a

kernel/power/swap.c

+27 −15
Original line number Diff line number Diff line
@@ -33,12 +33,14 @@ extern char resume_file[]; 


#define SWSUSP_SIG	"S1SUSPEND"



static struct swsusp_header {

struct swsusp_header {

	char reserved[PAGE_SIZE - 20 - sizeof(sector_t)];

	sector_t image;

	char	orig_sig[10];

	char	sig[10];

} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header;

} __attribute__((packed));



static struct swsusp_header *swsusp_header;



/*

 * General things
@@ -141,14 +143,14 @@ static int mark_swapfiles(sector_t start) 
{

	int error;



	bio_read_page(swsusp_resume_block, &swsusp_header, NULL);

	if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) ||

	    !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) {

		memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10);

		memcpy(swsusp_header.sig,SWSUSP_SIG, 10);

		swsusp_header.image = start;

	bio_read_page(swsusp_resume_block, swsusp_header, NULL);

	if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||

	    !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {

		memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);

		memcpy(swsusp_header->sig,SWSUSP_SIG, 10);

		swsusp_header->image = start;

		error = bio_write_page(swsusp_resume_block,

					&swsusp_header, NULL);

					swsusp_header, NULL);

	} else {

		printk(KERN_ERR "swsusp: Swap header not found!\n");

		error = -ENODEV;
@@ -564,7 +566,7 @@ int swsusp_read(void) 
	if (error < PAGE_SIZE)

		return error < 0 ? error : -EFAULT;

	header = (struct swsusp_info *)data_of(snapshot);

	error = get_swap_reader(&handle, swsusp_header.image);

	error = get_swap_reader(&handle, swsusp_header->image);

	if (!error)

		error = swap_read_page(&handle, header, NULL);

	if (!error)
@@ -591,17 +593,17 @@ int swsusp_check(void) 
	resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);

	if (!IS_ERR(resume_bdev)) {

		set_blocksize(resume_bdev, PAGE_SIZE);

		memset(&swsusp_header, 0, sizeof(swsusp_header));

		memset(swsusp_header, 0, sizeof(PAGE_SIZE));

		error = bio_read_page(swsusp_resume_block,

					&swsusp_header, NULL);

					swsusp_header, NULL);

		if (error)

			return error;



		if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) {

			memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);

		if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {

			memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);

			/* Reset swap signature now */

			error = bio_write_page(swsusp_resume_block,

						&swsusp_header, NULL);

						swsusp_header, NULL);

		} else {

			return -EINVAL;

		}
@@ -632,3 +634,13 @@ void swsusp_close(void) 


	blkdev_put(resume_bdev);

}



static int swsusp_header_init(void)

{

	swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);

	if (!swsusp_header)

		panic("Could not allocate memory for swsusp_header\n");

	return 0;

}



core_initcall(swsusp_header_init);

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