Hi Miklos, On Fri, Sep 09, 2016 at 04:32:49PM +0200, Miklos Szeredi wrote: > On Fri, Sep 9, 2016 at 3:34 PM, Antonio SJ Musumeci <trapexit@xxxxxxxxxx> wrote: > > https://gist.github.com/bauruine/3bc00075c4d0b5b3353071d208ded30f > > https://github.com/trapexit/mergerfs/issues/295 > > > > I've some users which are having issues with my filesystem where the > > system's load increases and then the kernel panics. > > > > Has anyone seen this before? > > Quite possibly this is caused by fuse, but the BUG is deep in mm > territory and I have zero clue about what it means. > > Hannes, can you please look a the above crash in mm/workingset.c? The MM maintains a reclaimable list of page cache tree nodes that have gone empty (all pages evicted) except for the shadow entries reclaimed pages leave behind. When faulting a regular page back into such a node the code in page_cache_tree_insert() removes it from the list again: workingset_node_pages_inc(node); /* * Don't track node that contains actual pages. * * Avoid acquiring the list_lru lock if already * untracked. The list_empty() test is safe as * node->private_list is protected by * mapping->tree_lock. */ if (!list_empty(&node->private_list)) list_lru_del(&workingset_shadow_nodes, &node->private_list); The BUG_ON() triggers when we later walk the reclaimable list and find a radix tree node that has actual pages in it. This could happen when pages are inserted into a mapping without using add_to_page_cache and related functions. Does that maybe ring a bell? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>