[i965g] igt@ - stray gpu writes
Submitted by LAKSHMINARAYANA VUDUM @l4kshmi
Assigned to Intel GFX Bugs mailing list
Link to original bug (#111939)
Description
`<4>` [390.262939] NMI backtrace for cpu 1<br>
`<4>` [390.262941] CPU: 1 PID: 1166 Comm: gem_ctx_isolati Tainted: G U 5.4.0-rc1-g78b99839aed8-drmtip_382+ #1<br>
`<4>` [390.262943] Hardware name: Dell Inc. OptiPlex 745 /0GW726, BIOS 2.3.1 05/21/2007<br>
`<4>` [390.262943] RIP: 0010:memchr+0x8/0x20<br>
`<4>` [390.262945] Code: 0b 48 83 c1 01 4c 39 c1 75 ed f3 c3 48 83 c0 01 4c 39 c2 73 dc 31 c0 c3 f3 c3 48 89 f8 c3 0f 1f 40 00 48 01 fa eb 0c 40 38 37 `<48>` 8d 47 01 74 0b 48 89 c7 48 39 d7 75 ef 31 c0 c3 48 89 f8 c3 0f<br>
`<4>` [390.262946] RSP: 0018:ffffa3dd808a7980 EFLAGS: 00000016<br>
`<4>` [390.262948] RAX: ffff9656bf5fa557 RBX: 000000000000004f RCX: 0000000000000001<br>
`<4>` [390.262949] RDX: ffff9656bf5fa58f RSI: 000000000000000a RDI: ffff9656bf5fa557<br>
`<4>` [390.262950] RBP: 000000000000000f R08: 0000000000000000 R09: 000000000000000f<br>
`<4>` [390.262951] R10: 0000000000000000 R11: ffffa3dd808a79b5 R12: ffffffff85b7c7c0<br>
`<4>` [390.262951] R13: ffffa3dd808a79a8 R14: 0000000000000000 R15: ffff9656bf5fa540<br>
`<4>` [390.262952] FS: 00007fafa0649e40(0000) GS:ffff9656bde80000(0000) knlGS:0000000000000000<br>
`<4>` [390.262953] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br>
`<4>` [390.262954] CR2: 00007faf9faaaddc CR3: 0000000039c30000 CR4: 00000000000006e0<br>
`<4>` [390.262955] Call Trace:<br>
`<4>` [390.262955] msg_print_text+0x138/0x260<br>
`<4>` [390.262956] ? console_unlock+0x8d/0x5b0<br>
`<4>` [390.262957] console_unlock+0x140/0x5b0<br>
`<4>` [390.262957] vprintk_emit+0xf7/0x340<br>
`<4>` [390.262958] printk+0x4d/0x69<br>
`<4>` [390.262959] trace_printk_seq+0x42/0x90<br>
`<4>` [390.262960] ftrace_dump+0x1ef/0x270<br>
`<4>` [390.262960] trace_die_handler+0x1b/0x30<br>
`<4>` [390.262961] notifier_call_chain+0x34/0x90<br>
`<4>` [390.262962] __atomic_notifier_call_chain+0x69/0x110<br>
`<4>` [390.262962] notify_die+0x5a/0xa0<br>
`<4>` [390.262963] __die+0xb0/0xd0<br>
`<4>` [390.262964] no_context+0x1b7/0x570<br>
`<4>` [390.262964] page_fault+0x34/0x40<br>
`<4>` [390.262965] RIP: 0010:__rb_erase_color+0xdb/0x260<br>
`<4>` [390.262967] Code: 48 8b 6b 08 48 39 d5 0f 85 64 ff ff ff 48 8b 6b 10 f6 45 00 01 4c 8b 6d 08 75 5c 48 89 d8 4c 89 6b 10 48 89 5d 08 48 83 c8 01 `<49>` 89 45 00 48 8b 03 48 89 45 00 48 83 e0 fc 48 89 2b 74 23 48 3b<br>
`<4>` [390.262968] RSP: 0018:ffffa3dd808a7d50 EFLAGS: 00010282<br>
`<4>` [390.262969] RAX: ffff9656b3333329 RBX: ffff9656b3333328 RCX: 0000000000000000<br>
`<4>` [390.262970] RDX: 0000000000000000 RSI: ffff9656ba7a7898 RDI: ffff9656b3333328<br>
`<4>` [390.262971] RBP: ffff96569fd694b0 R08: 0000000000000017 R09: 00000000fffffffe<br>
`<4>` [390.262972] R10: 000000008d7f774f R11: 00000000ff523dc8 R12: ffff9656ba7a7898<br>
`<4>` [390.262973] R13: 0000000000000000 R14: ffffffff8320bdf0 R15: 0000000000000000<br>
`<4>` [390.262974] ? vmacache_find+0xb0/0xb0<br>
`<4>` [390.262975] unlink_file_vma+0x36/0x50<br>
`<4>` [390.262975] free_pgtables+0xb9/0x110<br>
`<4>` [390.262976] exit_mmap+0xa3/0x180<br>
`<4>` [390.262977] mmput+0x5d/0x150<br>
`<4>` [390.262977] do_exit+0x5fb/0xd70<br>
`<4>` [390.262978] do_group_exit+0x42/0xb0<br>
`<4>` [390.262979] __x64_sys_exit_group+0xf/0x10<br>
`<4>` [390.262979] do_syscall_64+0x4f/0x210<br>
`<4>` [390.262980] entry_SYSCALL_64_after_hwframe+0x49/0xbe<br>
`<4>` [390.262981] RIP: 0033:0x7faf9faaae06<br>
`<4>` [390.262981] Code: Bad RIP value.<br>
`<4>` [390.262982] RSP: 002b:00007ffd21134f68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7<br>
`<4>` [390.262984] RAX: ffffffffffffffda RBX: 00007faf9fdad740 RCX: 00007faf9faaae06<br>
`<4>` [390.262985] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000<br>
`<4>` [390.262986] RBP: 0000000000000000 R08: 00000000000000e7 R09: ffffffffffffff80<br>
`<4>` [390.262987] R10: 00007faf93e260c0 R11: 0000000000000246 R12: 00007faf9fdad740<br>
`<4>` [390.262988] R13: 0000000000000003 R14: 00007faf9fdb6628 R15: 0000000000000000<br>
`<3>` [390.262997] rcu: rcu_preempt kthread starved for 65002 jiffies! g191829 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1<br>
`<0>` [390.263620] gem_exec-1067 1d..1 228653088us : __i915_request_submit: rcs0 fence 3:107601, current 107598<br>
`<3>` [390.264952] rcu: RCU grace-period kthread stack dump:<br>
`<0>` [390.266549] gem_exec-1067 1.... 228653212us : __i915_request_commit: rcs0 fence 3:107602<br>
`<6>` [390.267976] rcu_preempt I14368 10 2 0x80004000<br>
`<0>` [390.269564] gem_exec-1067 1d..1 228653224us : __i915_request_submit: rcs0 fence 3:107602, current 107598<br>
`<4>` [390.271162] Call Trace:<br>
`<0>` [390.272979] gem_exec-1067 1.... 228653382us : __i915_request_commit: rcs0 fence 3:107603<br>
`<4>` [390.274624] ? __schedule+0x2ef/0x7f0<br>
`<0>` [390.276440] gem_exec-1067 1d..1 228653395us : __i915_request_submit: rcs0 fence 3:107603, current 107598<br>
`<4>` [390.278075] schedule+0x34/0xc0<br>
`<0>` [390.279877] gem_exec-1067 1.... 228653522us : __i915_request_commit: rcs0 fence 3:107604<br>
`<4>` [390.281486] schedule_timeout+0x1cc/0x3f0<br>
`<0>` [390.283307] gem_exec-1067 1d..1 228653534us : __i915_request_submit: rcs0 fence 3:107604, current 107598<br>
`<4>` [390.284923] ? __next_timer_interrupt+0xc0/0xc0<br>
`<0>` [390.286725] gem_exec-1067 1.... 228653658us : __i915_request_commit: rcs0 fence 3:107605<br>
`<4>` [390.288318] rcu_gp_kthread+0x604/0xb70<br>
`<0>` [390.290095] gem_exec-1067 1d..1 228653671us : __i915_request_submit: rcs0 fence 3:107605, current 107598<br>
`<4>` [390.291668] ? rcu_barrier_func+0xa0/0xa0<br>
`<0>` [390.293414] gem_exec-1067 1.... 228653793us : __i915_request_commit: rcs0 fence 3:107606<br>
`<4>` [390.294972] kthread+0x119/0x130<br>
`<0>` [390.296724] gem_exec-1067 1d..1 228653806us : __i915_request_submit: rcs0 fence 3:107606, current 107598<br>
`<4>` [390.298297] ? kthread_park+0x80/0x80<br>
`<0>` [390.300064] gem_exec-1067 1.... 228653932us : __i915_request_commit: rcs0 fence 3:107607<br>
`<4>` [390.301649] ret_from_fork+0x3a/0x50