60694edf66
Fix the below splat: [ 142.510525] [IGT] xe_exec_basic: starting subtest once-userptr [ 142.511339] BUG: kernel NULL pointer dereference, address: 0000000000000228 [ 142.518311] #PF: supervisor read access in kernel mode [ 142.523458] #PF: error_code(0x0000) - not-present page [ 142.528604] PGD 0 P4D 0 [ 142.531153] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 142.535518] CPU: 4 PID: 1199 Comm: kworker/u16:8 Not tainted 6.1.0-rc1-xe+ #1 [ 142.542656] Hardware name: Intel Corporation Tiger Lake Client Platform/TigerLake U DDR4 SODIMM RVP, BIOS TGLSFWI1.R00.3243.A01.2006102133 06/10/2020 [ 142.556033] Workqueue: events_unbound async_op_work_func [xe] [ 142.561810] RIP: 0010:xe_bo_is_stolen+0x0/0x20 [xe] [ 142.566709] Code: 20 c8 75 05 83 fa 07 74 05 c3 cc cc cc cc 48 8b 87 08 02 00 00 0f b6 80 2c ff ff ff c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 <48> 8b 87 28 02 00 00 83 78 10 07 0f 94 c0 c3 cc cc cc cc 66 66 2e [ 142.585447] RSP: 0018:ffffc900019eb888 EFLAGS: 00010246 [ 142.590678] RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffff88813f6a2108 [ 142.597821] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 142.604962] RBP: ffffc900019ebbc0 R08: 0000000000000001 R09: 0000000000000000 [ 142.612101] R10: 0000000000000001 R11: 0000000000000001 R12: ffff88814107d600 [ 142.619242] R13: ffffc900019eba20 R14: ffff888140442000 R15: 0000000000000000 [ 142.626378] FS: 0000000000000000(0000) GS:ffff88849fa00000(0000) knlGS:0000000000000000 [ 142.634468] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 142.640219] CR2: 0000000000000228 CR3: 000000010a4c0006 CR4: 0000000000770ee0 [ 142.647361] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 142.654505] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 142.661639] PKRU: 55555554 [ 142.664367] Call Trace: [ 142.666830] <TASK> [ 142.668947] __xe_pt_bind_vma+0x1a1/0xa50 [xe] [ 142.673417] ? unwind_next_frame+0x187/0x770 [ 142.677699] ? __thaw_task+0xc0/0xc0 [ 142.681293] ? __lock_acquire+0x5e4/0x26e0 [ 142.685409] ? lockdep_hardirqs_on+0xbf/0x140 [ 142.689779] ? lock_acquire+0xd2/0x310 [ 142.693548] ? mark_held_locks+0x49/0x80 [ 142.697485] ? xe_vm_bind_vma+0xf1/0x3d0 [xe] [ 142.701866] xe_vm_bind_vma+0xf1/0x3d0 [xe] [ 142.706082] xe_vm_bind+0x76/0x140 [xe] [ 142.709944] vm_bind_ioctl+0x26f/0xb40 [xe] [ 142.714161] ? async_op_work_func+0x20c/0x450 [xe] [ 142.718974] async_op_work_func+0x20c/0x450 [xe] [ 142.723620] process_one_work+0x263/0x580 [ 142.727645] ? process_one_work+0x580/0x580 [ 142.731839] worker_thread+0x4d/0x3b0 [ 142.735518] ? process_one_work+0x580/0x580 [ 142.739714] kthread+0xeb/0x120 [ 142.742872] ? kthread_complete_and_exit+0x20/0x20 [ 142.747671] ret_from_fork+0x1f/0x30 [ 142.751264] </TASK> Signed-off-by: Matthew Brost <matthew.brost@intel.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.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.