629e052d0c
If the hfi1 module is loaded with HFI1_CAP_SDMA off, a call to hfi1_write_iter() will dereference a NULL pointer and panic. A typical stack frame is: sdma_select_user_engine [hfi1] hfi1_user_sdma_process_request [hfi1] hfi1_write_iter [hfi1] do_iter_readv_writev do_iter_write vfs_writev do_writev do_syscall_64 The fix is to test for SDMA in hfi1_write_iter() and fail the I/O with EINVAL. Link: https://lore.kernel.org/r/20220520183706.48973.79803.stgit@awfm-01.cornelisnetworks.com Signed-off-by: Douglas Miller <doug.miller@cornelisnetworks.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.