When I forced to enable atomic operations intentionally, I could hit the below panic, since we didn't clear page->private in f2fs_invalidate_page called by file truncation. The panic occurs due to NULL mapping having page->private. BUG: unable to handle kernel paging request at ffffffffffffffff IP: drop_buffers+0x38/0xe0 PGD 5d00c067 PUD 5d00e067 PMD 0 CPU: 3 PID: 1648 Comm: fsstress Tainted: G D OE 4.10.0+ #5 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 task: ffff9151952863c0 task.stack: ffffaaec40db4000 RIP: 0010:drop_buffers+0x38/0xe0 RSP: 0018:ffffaaec40db74c8 EFLAGS: 00010292 Call Trace: ? page_referenced+0x8b/0x170 try_to_free_buffers+0xc5/0xe0 try_to_release_page+0x49/0x50 shrink_page_list+0x8bc/0x9f0 shrink_inactive_list+0x1dd/0x500 ? shrink_active_list+0x2c0/0x430 shrink_node_memcg+0x5eb/0x7c0 shrink_node+0xe1/0x320 do_try_to_free_pages+0xef/0x2e0 try_to_free_pages+0xe9/0x190 __alloc_pages_slowpath+0x390/0xe70 __alloc_pages_nodemask+0x291/0x2b0 alloc_pages_current+0x95/0x140 __page_cache_alloc+0xc4/0xe0 pagecache_get_page+0xab/0x2a0 grab_cache_page_write_begin+0x20/0x40 get_read_data_page+0x2e6/0x4c0 [f2fs] ? f2fs_mark_inode_dirty_sync+0x16/0x30 [f2fs] ? truncate_data_blocks_range+0x238/0x2b0 [f2fs] get_lock_data_page+0x30/0x190 [f2fs] __exchange_data_block+0xaaf/0xf40 [f2fs] f2fs_fallocate+0x418/0xd00 [f2fs] vfs_fallocate+0x157/0x220 SyS_fallocate+0x48/0x80 Signed-off-by: Yunlei He <heyunlei@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> --- fs/f2fs/data.c | 2 +- fs/f2fs/f2fs.h | 1 + fs/f2fs/segment.c | 28 +++++++++++++++++++++------- 3 files changed, 23 insertions(+), 8 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index e07c60fb1033..f4b3006e3ecb 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1967,7 +1967,7 @@ void f2fs_invalidate_page(struct page *page, unsigned int offset, /* This is atomic written page, keep Private */ if (IS_ATOMIC_WRITTEN_PAGE(page)) - return; + drop_inmem_page(inode, page); set_page_private(page, 0); ClearPagePrivate(page); diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index e7b1a6c30d9e..9a06d0720351 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -2173,6 +2173,7 @@ void destroy_node_manager_caches(void); */ void register_inmem_page(struct inode *inode, struct page *page); void drop_inmem_pages(struct inode *inode); +void drop_inmem_page(struct inode *inode, struct page *page); int commit_inmem_pages(struct inode *inode); void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need); void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi); diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 42727e40d17c..3e8d08722151 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -192,7 +192,7 @@ void register_inmem_page(struct inode *inode, struct page *page) trace_f2fs_register_inmem_page(page, INMEM); } -static int __revoke_inmem_pages(struct inode *inode, +static int __revoke_inmem_pages(struct inode *inode, struct page *p, struct list_head *head, bool drop, bool recover) { struct f2fs_sb_info *sbi = F2FS_I_SB(inode); @@ -205,7 +205,10 @@ static int __revoke_inmem_pages(struct inode *inode, if (drop) trace_f2fs_commit_inmem_page(page, INMEM_DROP); - lock_page(page); + if (!p) + lock_page(page); + else if (p != page) + continue; if (recover) { struct dnode_of_data dn; @@ -229,7 +232,7 @@ static int __revoke_inmem_pages(struct inode *inode, ClearPageUptodate(page); set_page_private(page, 0); ClearPagePrivate(page); - f2fs_put_page(page, 1); + f2fs_put_page(page, p ? 0 : 1); list_del(&cur->list); kmem_cache_free(inmem_entry_slab, cur); @@ -243,13 +246,22 @@ void drop_inmem_pages(struct inode *inode) struct f2fs_inode_info *fi = F2FS_I(inode); mutex_lock(&fi->inmem_lock); - __revoke_inmem_pages(inode, &fi->inmem_pages, true, false); + __revoke_inmem_pages(inode, NULL, &fi->inmem_pages, true, false); mutex_unlock(&fi->inmem_lock); clear_inode_flag(inode, FI_ATOMIC_FILE); stat_dec_atomic_write(inode); } +void drop_inmem_page(struct inode *inode, struct page *page) +{ + struct f2fs_inode_info *fi = F2FS_I(inode); + + mutex_lock(&fi->inmem_lock); + __revoke_inmem_pages(inode, page, &fi->inmem_pages, true, false); + mutex_unlock(&fi->inmem_lock); +} + static int __commit_inmem_pages(struct inode *inode, struct list_head *revoke_list) { @@ -300,7 +312,7 @@ static int __commit_inmem_pages(struct inode *inode, DATA, WRITE); if (!err) - __revoke_inmem_pages(inode, revoke_list, false, false); + __revoke_inmem_pages(inode, NULL, revoke_list, false, false); return err; } @@ -330,12 +342,14 @@ int commit_inmem_pages(struct inode *inode) * recovery or rewrite & commit last transaction. For other * error number, revoking was done by filesystem itself. */ - ret = __revoke_inmem_pages(inode, &revoke_list, false, true); + ret = __revoke_inmem_pages(inode, NULL, &revoke_list, + false, true); if (ret) err = ret; /* drop all uncommitted pages */ - __revoke_inmem_pages(inode, &fi->inmem_pages, true, false); + __revoke_inmem_pages(inode, NULL, &fi->inmem_pages, + true, false); } mutex_unlock(&fi->inmem_lock); -- 2.11.0