Comment 10 for bug 247148

Revision history for this message
Stefan Bader (smb) wrote :

SRU justification:

Impact: Using SWIOMMU unnecessarily causes "out of space" errors and subsequently causes corruptions in software RAID (and probably also caused the problems mentioned in https://bugs.launchpad.net/ubuntu/+source/linux/+bug/238118/comments/9).

Fix: (taken from the Xen changelog) This patch adds a new check, check_pages_physically_contiguous(),
to the test for pages stradding page boundaries both in swiotlb_map_sg() and dma_map_sg(), to capture these ranges and map them directly via virt_to_bus() mapping rather than through the swiotlb.

Testcase: See above.