7ed2632ec7
The QXL driver doesn't use any device for DMA mappings or allocations so dev_to_node() will panic inside ttm_device_init() on NUMA systems: general protection fault, probably for non-canonical address 0xdffffc000000007a: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x00000000000003d0-0x00000000000003d7] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.7.0+ #9 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 RIP: 0010:ttm_device_init+0x10e/0x340 Call Trace: qxl_ttm_init+0xaa/0x310 qxl_device_init+0x1071/0x2000 qxl_pci_probe+0x167/0x3f0 local_pci_probe+0xe1/0x1b0 pci_device_probe+0x29d/0x790 really_probe+0x251/0x910 __driver_probe_device+0x1ea/0x390 driver_probe_device+0x4e/0x2e0 __driver_attach+0x1e3/0x600 bus_for_each_dev+0x12d/0x1c0 bus_add_driver+0x25a/0x590 driver_register+0x15c/0x4b0 qxl_pci_driver_init+0x67/0x80 do_one_initcall+0xf5/0x5d0 kernel_init_freeable+0x637/0xb10 kernel_init+0x1c/0x2e0 ret_from_fork+0x48/0x80 ret_from_fork_asm+0x1b/0x30 RIP: 0010:ttm_device_init+0x10e/0x340 Fall back to NUMA_NO_NODE if there is no device for DMA. Found by Linux Verification Center (linuxtesting.org). Fixes: b0a7ce53d494 ("drm/ttm: Schedule delayed_delete worker closer") Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Reviewed-by: Christian König <christian.koenig@amd.com> Reported-by: Steven Rostedt <rostedt@goodmis.org> Cc: Rajneesh Bhardwaj <rajneesh.bhardwaj@amd.com> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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.