Hangs or crashes when using Ver 0.11.10 with XFS

[yito24]

I tested 0.11.10 on the following operating systems:

• RHEL9.5 with XFS
• Ubuntu24.04 LTS with XFS
• openSUSE 15.6 with XFS

Using XFS on this OS causes crashes.
No crashes with EXT4.

This occurs in this function.
[ bio_needs_cow ]

I've attached the dmesg.txt from Ubuntu 24.04.
dmesg.202412231756.txt

Already reported for RHEL9.5.
#396 (comment)

[iamandrii]

Hi @yito24, thank you for the dmesg.

The issue is currently under investigation. Hope to fix it soon.

[yito24]

I have merged the elastio-snap code and am testing it, and no crashes have occurred.
Hope this helps!!

bio_helper.c

	if (PageAnon(pg))
		return NULL;
	if (!pg->mapping)
		return NULL;
	if (!virt_addr_valid(pg->mapping))
		return NULL;
	return pg->mapping->host;

	int bio_needs_cow(struct bio *bio, struct inode *inode)
{
	bio_iter_t iter;
	bio_iter_bvec_t bvec;

	/*if (!test_bit(COW_ON_BDEV, &dev->sd_cow_state)) {
		return 1;
	}*/

#if (defined HAVE_ENUM_REQ_OPF) || \
	(defined HAVE_ENUM_REQ_OP && defined HAVE_WRITE_ZEROES)
	// HAVE_ENUM_REQ_OPF: KERNEL_VERSION >= 4.10 && KERNEL_VERSION <= 5.19
	// HAVE_ENUM_REQ_OP: KERNEL_VERSION < 4.10 && KERNEL_VERSION >= 6.0
	// HAVE_WRITE_ZEROES: KERNEL_VERSION >= 4.10
	if(bio_op(bio) == REQ_OP_WRITE_ZEROES)
		return 1;
#endif

	//check the inode of each page return true if it does not match our cow file
	bio_for_each_segment(bvec, bio, iter) {
		if (page_get_inode(bio_iter_page(bio, iter)) != inode){
			return 1;
		}
	}

	return 0;

[iamandrii]

Thanks, will take a look soon)