da26e5729c
[ Upstream commit 1d0ffd264204eba1861865560f1f7f7a92919384 ] In raid10 reshape_request it gets max_sectors in read_balance. If the underlayer disks have bad blocks, the max_sectors is less than last. It will call goto read_more many times. It calls raise_barrier(conf, sectors_done != 0) every time. In this condition sectors_done is not 0. So the value passed to the argument force of raise_barrier is true. In raise_barrier it checks conf->barrier when force is true. If force is true and conf->barrier is 0, it panic. In this case reshape_request submits bio to under layer disks. And in the callback function of the bio it calls lower_barrier. If the bio finishes before calling raise_barrier again, it can trigger the BUG_ON. Add one pair of raise_barrier/lower_barrier to fix this bug. Signed-off-by: Xiao Ni <xni@redhat.com> Suggested-by: Neil Brown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.