Hi all, I've hit generic/224 flooding dmesg on 512 block size XFS, 4.8-rc1 kernel, with the following message: ... [ 98.146091] XFS (sda6): page discard on page ffffea0002f7e780, inode 0xe3a87, offset 1085214720. [ 98.147431] XFS (sda6): page discard on page ffffea00023c3800, inode 0xe3a87, offset 1085218816. [ 98.148743] XFS (sda6): page discard on page ffffea0002247700, inode 0xe3a87, offset 1085222912. [ 98.150136] XFS (sda6): page discard on page ffffea0002f8d000, inode 0xe3a87, offset 1085227008. [ 98.151496] XFS (sda6): page discard on page ffffea0002c58840, inode 0xe3a87, offset 1085231104. [ 98.152794] XFS (sda6): page discard on page ffffea0002e65340, inode 0xe3a87, offset 1085235200. ... The inode number is always the same, only the page address and offset are changing. This is triggered by this dd command in generic/224: dd if=/dev/zero of=$SCRATCH_MNT/testfile.$i bs=4k conv=notrunc and it won't return until you kill it. With 4.7 kernel I can see similar messages in dmesg, but only a few lines are printed on different inodes, I don't see this infinite loop on same inode. And I bisected to this commit: commit 68a9f5e7007c1afa2cf6830b690a90d0187c0684 Author: Christoph Hellwig <hch@xxxxxx> Date: Tue Jun 21 09:53:44 2016 +1000 xfs: implement iomap based buffered write path Convert XFS to use the new iomap based multipage write path. This involves implementing the ->iomap_begin and ->iomap_end methods, and switching the buffered file write, page_mkwrite and xfs_iozero paths to the new iomap helpers. With this change __xfs_get_blocks will never be used for buffered writes, and the code handling them can be removed. Based on earlier code from Dave Chinner. Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Bob Peterson <rpeterso@xxxxxxxxxx> Signed-off-by: Dave Chinner <david@xxxxxxxxxxxxx> I was testing on x86_64 kvm guest with 8G memory and 4vcpus. If more information is needed please let me know. Thanks, Eryu _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs