From: Balbir Singh Move mem_controller_cache_charge() above radix_tree_preload(). radix_tree_preload() disables preemption, even though the gfp_mask passed contains __GFP_WAIT, we cannot really do __GFP_WAIT allocations, thus we hit a BUG_ON() in kmem_cache_alloc(). This patch moves mem_controller_cache_charge() to above radix_tree_preload() for cache charging. Signed-off-by: Balbir Singh Signed-off-by: Andrew Morton --- mm/filemap.c | 13 ++++++------- mm/swap_state.c | 13 +++++++------ 2 files changed, 13 insertions(+), 13 deletions(-) diff -puN mm/filemap.c~memory-controller-bug_on mm/filemap.c --- a/mm/filemap.c~memory-controller-bug_on +++ a/mm/filemap.c @@ -440,14 +440,12 @@ int filemap_write_and_wait_range(struct int add_to_page_cache(struct page *page, struct address_space *mapping, pgoff_t offset, gfp_t gfp_mask) { - int error = radix_tree_preload(gfp_mask & ~__GFP_HIGHMEM); + int error = mem_cgroup_cache_charge(page, current->mm, gfp_mask); + if (error) + goto out; + error = radix_tree_preload(gfp_mask & ~__GFP_HIGHMEM); if (error == 0) { - - error = mem_cgroup_cache_charge(page, current->mm, gfp_mask); - if (error) - goto out; - write_lock_irq(&mapping->tree_lock); error = radix_tree_insert(&mapping->page_tree, offset, page); if (!error) { @@ -462,7 +460,8 @@ int add_to_page_cache(struct page *page, write_unlock_irq(&mapping->tree_lock); radix_tree_preload_end(); - } + } else + mem_cgroup_uncharge_page(page); out: return error; } diff -puN mm/swap_state.c~memory-controller-bug_on mm/swap_state.c --- a/mm/swap_state.c~memory-controller-bug_on +++ a/mm/swap_state.c @@ -78,13 +78,13 @@ static int __add_to_swap_cache(struct pa BUG_ON(!PageLocked(page)); BUG_ON(PageSwapCache(page)); BUG_ON(PagePrivate(page)); - error = radix_tree_preload(gfp_mask); - if (!error) { - error = mem_cgroup_cache_charge(page, current->mm, gfp_mask); - if (error) - goto out; + error = mem_cgroup_cache_charge(page, current->mm, gfp_mask); + if (error) + goto out; + error = radix_tree_preload(gfp_mask); + if (!error) { write_lock_irq(&swapper_space.tree_lock); error = radix_tree_insert(&swapper_space.page_tree, entry.val, page); @@ -99,7 +99,8 @@ static int __add_to_swap_cache(struct pa write_unlock_irq(&swapper_space.tree_lock); radix_tree_preload_end(); - } + } else + mem_cgroup_uncharge_page(page); out: return error; } _