On Wed, Aug 03, 2022 at 10:52:43AM +0800, Yin Fengwei wrote: > If there is private data attached to THP, the refcount of > THP will be increased and block the THP split. Which could > further cause the meomry failure not recovered. > > Release private data attached to THP before split it to > increase the chance of splitting THP successfully. > > The issue was hit during HW error injection testing with > 5.18 kernel + xfs as rootfs, test got killed and system > reboot was required to re-run the test. > > The issue was tracked down to THP split failure caused the > memory failure not being handled. The page dump showed: > > [ 1785.433075] page:0000000025f9530b refcount:18 mapcount:0 mapping:000000008162eea7 index:0xa10 pfn:0x2f0200 > [ 1785.443954] head:0000000025f9530b order:4 compound_mapcount:0 compound_pincount:0 > [ 1785.452408] memcg:ff4247f2d28e9000 > [ 1785.456304] aops:xfs_address_space_operations ino:8555182 dentry name:"baseos-filenames.solvx" > [ 1785.466612] flags: 0x1000000000012036(referenced|uptodate|lru|active|private|head|node=0|zone=2) > [ 1785.476514] raw: 1000000000012036 ffb9460f8bc07c08 ffb9460f8bc08408 ff4247f22e6299f8 > [ 1785.485268] raw: 0000000000000a10 ff4247f194ade900 00000012ffffffff ff4247f2d28e9000 > > It was like the error was injected to a large folio for xfs with > private data attached. > > With private data released before split THP, the test case > could be run successfully many times without reboot system. > > Signed-off-by: Yin Fengwei <fengwei.yin@xxxxxxxxx> > Reviewed-by: Aaron Lu <aaron.lu@xxxxxxxxx> Thank you for the patch, It looks reasonable to me so far. Reviewed-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
