From: Amir Goldstein <amir73il@gmail.com> stable inclusion from stable-v6.6.8 commit fbcddc7410625f90a3c1352c503d286bb23c1a60 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8ST59 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 3f29f1c336c0e8a4bec52f1e5217f88835553e5b upstream. The new fuse init flag FUSE_DIRECT_IO_ALLOW_MMAP breaks assumptions made by FOPEN_PARALLEL_DIRECT_WRITES and causes test generic/095 to hit BUG_ON(fi->writectr < 0) assertions in fuse_set_nowrite(): generic/095 5s ... kernel BUG at fs/fuse/dir.c:1756! ... ? fuse_set_nowrite+0x3d/0xdd ? do_raw_spin_unlock+0x88/0x8f ? _raw_spin_unlock+0x2d/0x43 ? fuse_range_is_writeback+0x71/0x84 fuse_sync_writes+0xf/0x19 fuse_direct_io+0x167/0x5bd fuse_direct_write_iter+0xf0/0x146 Auto disable FOPEN_PARALLEL_DIRECT_WRITES when server negotiated FUSE_DIRECT_IO_ALLOW_MMAP. Fixes: e78662e818f9 ("fuse: add a new fuse init flag to relax restrictions in no cache mode") Cc: <stable@vger.kernel.org> # v6.6 Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- fs/fuse/file.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 89e870d1a526..a660f1f21540 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1574,6 +1574,7 @@ static ssize_t fuse_direct_write_iter(struct kiocb *iocb, struct iov_iter *from) ssize_t res; bool exclusive_lock = !(ff->open_flags & FOPEN_PARALLEL_DIRECT_WRITES) || + get_fuse_conn(inode)->direct_io_allow_mmap || iocb->ki_flags & IOCB_APPEND || fuse_direct_write_extending_i_size(iocb, from); @@ -1581,6 +1582,7 @@ static ssize_t fuse_direct_write_iter(struct kiocb *iocb, struct iov_iter *from) * Take exclusive lock if * - Parallel direct writes are disabled - a user space decision * - Parallel direct writes are enabled and i_size is being extended. + * - Shared mmap on direct_io file is supported (FUSE_DIRECT_IO_ALLOW_MMAP). * This might not be needed at all, but needs further investigation. */ if (exclusive_lock) -- 2.20.1