Hi Jaegeuk,
On 2017/3/22 10:41, Jaegeuk Kim wrote:
> Hi Chao,
>
> Please let me make one patch by integrating into my original patch like this.
> I slightly changed drop_inmem_page() as well.
The merged patch looks good to me. ;)
Thanks,
>
> Thanks,
>
>>From 8c242db9b8c01b252290e23827163787f07e01d1 Mon Sep 17 00:00:00 2001
> From: Jaegeuk Kim <jaeg...@kernel.org>
> Date: Fri, 17 Mar 2017 09:55:52 +0800
> Subject: [PATCH] f2fs: fix stale ATOMIC_WRITTEN_PAGE private pointer
>
> 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 <heyun...@huawei.com>
> Signed-off-by: Chao Yu <yuch...@huawei.com>
> [Chao Yu: use INMEM_INVALIDATE for better tracing]
> Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
> ---
> fs/f2fs/data.c | 2 +-
> fs/f2fs/f2fs.h | 2 ++
> fs/f2fs/segment.c | 30 ++++++++++++++++++++++++++++++
> include/trace/events/f2fs.h | 2 ++
> 4 files changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 1602b4bccae6..e341d446205a 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -1951,7 +1951,7 @@ void f2fs_invalidate_page(struct page *page, unsigned
> int offset,
>
> /* This is atomic written page, keep Private */
> if (IS_ATOMIC_WRITTEN_PAGE(page))
> - return;
> + 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 0a6e115562f6..264c219f41a5 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -722,6 +722,7 @@ enum page_type {
> META_FLUSH,
> INMEM, /* the below types are used by tracepoints only. */
> INMEM_DROP,
> + INMEM_INVALIDATE,
> INMEM_REVOKE,
> IPU,
> OPU,
> @@ -2184,6 +2185,7 @@ 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 4d7bf84dc393..cb6d9ed634a3 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -250,6 +250,36 @@ void drop_inmem_pages(struct inode *inode)
> stat_dec_atomic_write(inode);
> }
>
> +void drop_inmem_page(struct inode *inode, struct page *page)
> +{
> + struct f2fs_inode_info *fi = F2FS_I(inode);
> + struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> + struct list_head *head = &fi->inmem_pages;
> + struct inmem_pages *cur = NULL;
> +
> + f2fs_bug_on(sbi, !IS_ATOMIC_WRITTEN_PAGE(page));
> +
> + mutex_lock(&fi->inmem_lock);
> + list_for_each_entry(cur, head, list) {
> + if (cur->page == page)
> + break;
> + }
> +
> + f2fs_bug_on(sbi, !cur || cur->page != page);
> + list_del(&cur->list);
> + mutex_unlock(&fi->inmem_lock);
> +
> + dec_page_count(sbi, F2FS_INMEM_PAGES);
> + kmem_cache_free(inmem_entry_slab, cur);
> +
> + ClearPageUptodate(page);
> + set_page_private(page, 0);
> + ClearPagePrivate(page);
> + f2fs_put_page(page, 0);
> +
> + trace_f2fs_commit_inmem_page(page, INMEM_INVALIDATE);
> +}
> +
> static int __commit_inmem_pages(struct inode *inode,
> struct list_head *revoke_list)
> {
> diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h
> index c80fcad0a6c9..96139021b6bc 100644
> --- a/include/trace/events/f2fs.h
> +++ b/include/trace/events/f2fs.h
> @@ -15,6 +15,7 @@ TRACE_DEFINE_ENUM(META);
> TRACE_DEFINE_ENUM(META_FLUSH);
> TRACE_DEFINE_ENUM(INMEM);
> TRACE_DEFINE_ENUM(INMEM_DROP);
> +TRACE_DEFINE_ENUM(INMEM_INVALIDATE);
> TRACE_DEFINE_ENUM(IPU);
> TRACE_DEFINE_ENUM(OPU);
> TRACE_DEFINE_ENUM(CURSEG_HOT_DATA);
> @@ -51,6 +52,7 @@ TRACE_DEFINE_ENUM(CP_DISCARD);
> { META_FLUSH, "META_FLUSH" }, \
> { INMEM, "INMEM" }, \
> { INMEM_DROP, "INMEM_DROP" }, \
> + { INMEM_INVALIDATE, "INMEM_INVALIDATE" }, \
> { INMEM_REVOKE, "INMEM_REVOKE" }, \
> { IPU, "IN-PLACE" }, \
> { OPU, "OUT-OF-PLACE" })
>
