igt/gem_mmap_gtt: Exercise concurrent pagefaulting
This should hit the BUG inside remap_pfn_range in
commit
c5158fabeaf53ed2c614c3333aaa4b3cce80f500
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue Jun 10 12:14:41 2014 +0100
[ 27.767634] kernel BUG at mm/memory.c:2315!
[ 27.767655] invalid opcode: 0000 [#1] SMP
[ 27.767679] Modules linked in: cpufreq_userspace cpufreq_powersave cpufreq_stats cpufreq_conservative binfmt_misc nfs lockd fscache sunrpc hid_generic usbhid hid x86_pkg_temp_thermal microcode i2c_i801 lpc_ich mfd_core battery acpi_cpufreq evdev processor ac loop ehci_pci xhci_hcd ehci_hcd sr_mod usbcore cdrom usb_common fan thermal
[ 27.767872] CPU: 3 PID: 912 Comm: gem_mmap_gtt Not tainted 3.15.0-rc8+ #953
[ 27.767903] Hardware name: Intel Corporation Shark Bay Client platform/Flathead Creek Crb, BIOS HSWLPTU1.86C.0109.R03.
1301282055 01/28/2013
[ 27.767956] task:
ffff880448415010 ti:
ffff88044d22c000 task.ti:
ffff88044d22c000
[ 27.767988] RIP: 0010:[<
ffffffff81130734>] [<
ffffffff81130734>] remap_pfn_range+0x2a4/0x400
[ 27.768033] RSP: 0000:
ffff88044d22fc28 EFLAGS:
00010282
[ 27.768057] RAX:
0000000000020002 RBX:
00000000000a3b57 RCX:
ffff880448b73fe8
[ 27.768088] RDX:
0000000000000002 RSI:
ffff880000000000 RDI:
ffffea000efe8158
[ 27.768119] RBP:
ffff88044d22fcd8 R08:
00007fc7b57fe000 R09:
00007fc7b57fe000
[ 27.768150] R10:
00000000000001fd R11:
0000000000000a9a R12:
ffffea000efe8128
[ 27.768180] R13:
0000000000000001 R14:
00007fc7b57fd000 R15:
800000000000002f
[ 27.768212] FS:
00007fc7977fc700(0000) GS:
ffff88045e380000(0000) knlGS:
0000000000000000
[ 27.768246] CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
[ 27.768272] CR2:
00007fc7b67fd000 CR3:
000000044866c000 CR4:
00000000001407e0
[ 27.768303] DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
[ 27.768333] DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
[ 27.768363] Stack:
[ 27.768374]
ffff880448bbb6f8 00000000ffffffff 00007fc7b57fdfff 00007fc7b57fdfff
[ 27.768414]
00007fc7b57fe000 ffff88044866c7f8 ffff8804496b08f0 00007fc7b57fdfff
[ 27.768454]
fffffff8038ee35a 0000000000001000 ffff88044c208180 00007fc7b57fe000
[ 27.768494] Call Trace:
[ 27.768511] [<
ffffffff81365277>] i915_gem_fault+0x337/0x340
[ 27.768538] [<
ffffffff8112d3c4>] __do_fault+0x34/0x70
[ 27.768565] [<
ffffffff8109088e>] ? wake_up_process+0x1e/0x40
[ 27.768592] [<
ffffffff8113015c>] do_shared_fault.isra.96+0x2c/0x1f0
[ 27.768623] [<
ffffffff81502405>] ? rwsem_down_read_failed+0xe5/0x130
[ 27.768654] [<
ffffffff810a2519>] ? __rwsem_do_wake+0x129/0x160
[ 27.768682] [<
ffffffff81131085>] handle_mm_fault+0x2b5/0xb80
[ 27.768712] [<
ffffffff81270a64>] ? call_rwsem_down_read_failed+0x14/0x30
[ 27.768745] [<
ffffffff81036c67>] __do_page_fault+0x167/0x4c0
[ 27.768774] [<
ffffffff8109a540>] ? pick_next_task_fair+0x700/0x870
[ 27.768804] [<
ffffffff814ff23b>] ? __schedule+0x27b/0x860
[ 27.768831] [<
ffffffff81036fec>] do_page_fault+0xc/0x10
[ 27.768857] [<
ffffffff815034a2>] page_fault+0x22/0x30
[ 27.768881] Code: 4d 85 ed 49 0f 44 d7 80 cc 02 49 81 c6 00 10 00 00 48 83 c3 01 48 83 c1 08 48 09 d0 48 89 41 f8 4d 39 f0 74 32 48 83 39 00 74 c4 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 48 39 37 75 63 48 8b 45 c8
[ 27.769081] RIP [<
ffffffff81130734>] remap_pfn_range+0x2a4/0x400
[ 27.769113] RSP <
ffff88044d22fc28>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>