From 717beb96d969561cff53aad2f09547db20ee6ffd Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 25 Jun 2018 10:03:41 -0700 Subject: [PATCH] Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion The vm_fault_t conversion commit introduced a ret2 variable for tracking the integer return values from internal btrfs functions. It was sometimes returning VM_FAULT_LOCKED for pages that were actually invalid and had been removed from the radix. Something like this: ret2 = btrfs_delalloc_reserve_space() // returns zero on success lock_page(page) if (page->mapping != inode->i_mapping) goto out_unlock; ... out_unlock: if (!ret2) { ... return VM_FAULT_LOCKED; } This ends up triggering this WARNING in btrfs_destroy_inode() WARN_ON(BTRFS_I(inode)->block_rsv.size); xfstests generic/095 was able to reliably reproduce the errors. Since out_unlock: is only used for errors, this fix moves it below the if (!ret2) check we use to return VM_FAULT_LOCKED for success. Fixes: a528a2415087 (btrfs: change return type of btrfs_page_mkwrite to vm_fault_t) Signed-off-by: Chris Mason Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/inode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index a6bf9e2ff68f..f21f4223d03b 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -9005,13 +9005,14 @@ again: unlock_extent_cached(io_tree, page_start, page_end, &cached_state); -out_unlock: if (!ret2) { btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, true); sb_end_pagefault(inode->i_sb); extent_changeset_free(data_reserved); return VM_FAULT_LOCKED; } + +out_unlock: unlock_page(page); out: btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, (ret != 0));