On Sat, 2017-10-07 at 17:55 +0800, Jia-Ju Bai wrote: > The kernel may sleep under a spinlock, and the function call paths are: > afs_do_unlk (acquire the spinlock) > posix_lock_file > posix_lock_inode (fs/locks.c) > locks_get_lock_context > kmem_cache_alloc(GFP_KERNEL) --> may sleep > > afs_do_setlk (acquire the spinlock) > posix_lock_file > posix_lock_inode (fs/locks.c) > locks_get_lock_context > kmem_cache_alloc(GFP_KERNEL) --> may sleep > > To fix them, GFP_KERNEL is replaced with GFP_ATOMIC. > These bugs are found by my static analysis tool and my code review. > > Signed-off-by: Jia-Ju Bai <[email protected]> > --- > fs/locks.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/locks.c b/fs/locks.c > index 1bd71c4..975cc62 100644 > --- a/fs/locks.c > +++ b/fs/locks.c > @@ -222,7 +222,7 @@ struct file_lock_list_struct { > if (likely(ctx) || type == F_UNLCK) > goto out; > > - ctx = kmem_cache_alloc(flctx_cache, GFP_KERNEL); > + ctx = kmem_cache_alloc(flctx_cache, GFP_ATOMIC); > if (!ctx) > goto out; >
NAK This needs to be fixed in the AFS code. It should not be calling these functions with a spinlock held. -- Jeff Layton <[email protected]>
