| Message ID | 20181127211634.4995-2-willy@infradead.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | c93db7bb6ef3251e0ea48ade311d3e9942748e1c |
| Headers | show |
| Series | Two DAX fixes for 4.20 | expand |
Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
On Tue 27-11-18 13:16:33, Matthew Wilcox wrote: > If we race with inode destroy, it's possible for page->mapping to be > NULL before we even enter this routine, as well as after having slept > waiting for the dax entry to become unlocked. > > Fixes: c2a7d2a11552 ("filesystem-dax: Introduce dax_lock_mapping_entry()") > Cc: stable@vger.kernel.org > Reported-by: Jan Kara <jack@suse.cz> > Signed-off-by: Matthew Wilcox <willy@infradead.org> Thanks for writing this fix. The patch looks good. You can add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > fs/dax.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/dax.c b/fs/dax.c > index 9bcce89ea18e..e69fc231833b 100644 > --- a/fs/dax.c > +++ b/fs/dax.c > @@ -365,7 +365,7 @@ bool dax_lock_mapping_entry(struct page *page) > struct address_space *mapping = READ_ONCE(page->mapping); > > locked = false; > - if (!dax_mapping(mapping)) > + if (!mapping || !dax_mapping(mapping)) > break; > > /* > -- > 2.19.1 >
diff --git a/fs/dax.c b/fs/dax.c index 9bcce89ea18e..e69fc231833b 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -365,7 +365,7 @@ bool dax_lock_mapping_entry(struct page *page) struct address_space *mapping = READ_ONCE(page->mapping); locked = false; - if (!dax_mapping(mapping)) + if (!mapping || !dax_mapping(mapping)) break; /*
If we race with inode destroy, it's possible for page->mapping to be NULL before we even enter this routine, as well as after having slept waiting for the dax entry to become unlocked. Fixes: c2a7d2a11552 ("filesystem-dax: Introduce dax_lock_mapping_entry()") Cc: stable@vger.kernel.org Reported-by: Jan Kara <jack@suse.cz> Signed-off-by: Matthew Wilcox <willy@infradead.org> --- fs/dax.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)