No visual output with hardened-sources-4.1.3-r1. Log analysis shows kernel oops. While enabling kernel option CONFIG_DRM_RADEON_USERPTR - which basically selects CONFIG_MMU_NOTIFIER used with for e.g. KVM causes hard lockup during boot making the machine unresponsive requiring hard reset. Even sysrq doesn't help. Reproducible: Always Actual Results: Jul 29 13:33:13 kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 Jul 29 13:33:13 kernel: IP: [<ffffffffc01611b3>] evergreen_bandwidth_update+0x63/0x120 [radeon] Jul 29 13:33:13 kernel: PGD 0 Jul 29 13:33:13 kernel: Oops: 0000 [#1] SMP DEBUG_PAGEALLOC Jul 29 13:33:13 kernel: Modules linked in: x86_pkg_temp_thermal coretemp microcode radeon(+) xhci_pci xhci_hcd cfbfillrect cfbimgblt cfbcopyarea drm_kms_helper ttm ehci_pci ehci_hcd Jul 29 13:33:13 kernel: CPU: 4 PID: 1824 Comm: laptop_mode Not tainted 4.1.3-hardened-r1 #2 Jul 29 13:33:13 kernel: Hardware name: Hewlett-Packard HP EliteBook 8560w/1631, BIOS 68SVD Ver. F.50 08/04/2014 Jul 29 13:33:13 kernel: task: ffff8800b938e050 ti: ffff8800b938ec80 task.ti: ffff8800b938ec80 Jul 29 13:33:13 kernel: RIP: 0010:[<ffffffffc01611b3>] [<ffffffffc01611b3>] evergreen_bandwidth_update+0x63/0x120 [radeon] Jul 29 13:33:13 kernel: RSP: 0018:ffffc9000666bc78 EFLAGS: 00010246 Jul 29 13:33:13 kernel: RAX: ffff8800b91a04b0 RBX: ffff8800b91a0000 RCX: ffff8800b91a04e0 Jul 29 13:33:13 kernel: RDX: 0000000000000000 RSI: ffffffffc0161150 RDI: ffff8800b91a0000 Jul 29 13:33:13 kernel: RBP: ffff8800b91a1b78 R08: ffff8800b90fbe92 R09: 000000000000044c Jul 29 13:33:13 kernel: R10: ffff8800b91a1e90 R11: 0000000000006678 R12: 0000000000000000 Jul 29 13:33:13 kernel: R13: 8000000000000000 R14: ffff8800b91a1ba0 R15: ffff8800b91a14b0 Jul 29 13:33:13 kernel: FS: 0000033072497700(0000) GS:ffff88023cd00000(0000) knlGS:0000000000000000 Jul 29 13:33:13 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Jul 29 13:33:13 kernel: CR2: 0000000000000090 CR3: 0000000025e56000 CR4: 00000000000607f0 Jul 29 13:33:13 kernel: Stack: Jul 29 13:33:13 kernel: ffff8800b91a1b78 ffff8800b91a0000 ffff8800b91a1b78 0000000000000001 Jul 29 13:33:13 kernel: 8000000000000000 ffff8800b91a1ba0 ffff8800b91a14b0 ffffffffc0158359 Jul 29 13:33:13 kernel: ffff8800b91a1b78 ffff8800b91a0000 ffff8800b91a1b78 000000000000000c Jul 29 13:33:13 kernel: Call Trace: Jul 29 13:33:13 kernel: [<ffffffffc0158359>] ? radeon_pm_compute_clocks+0x6e9/0x950 [radeon] Jul 29 13:33:13 kernel: [<ffffffffc0158beb>] ? radeon_set_dpm_state+0x7b/0x140 [radeon] Jul 29 13:33:13 kernel: [<ffffffffa527d3a2>] ? kernfs_fop_write+0x142/0x490 Jul 29 13:33:13 kernel: [<ffffffffa51f2206>] ? __vfs_write+0x56/0x150 Jul 29 13:33:13 kernel: [<ffffffffa51f5f4d>] ? __sb_start_write+0x4d/0x120 Jul 29 13:33:13 kernel: [<ffffffffa54e8518>] ? security_file_permission+0x28/0xb0 Jul 29 13:33:13 kernel: [<ffffffffa51f2c5c>] ? vfs_write+0xfc/0x2a0 Jul 29 13:33:13 kernel: [<ffffffffa51f3f39>] ? SyS_write+0x59/0xe0 Jul 29 13:33:13 kernel: [<ffffffffa5e3a399>] ? system_call_fastpath+0x12/0x83 Jul 29 13:33:13 kernel: [<ffffffffa5e3af10>] ? retint_swapgs+0xe/0x16 Jul 29 13:33:13 kernel: Code: 8b 93 f0 24 00 00 85 d2 7e d8 48 8d 83 b0 04 00 00 83 ea 01 45 31 e4 48 8d 8c d3 b8 04 00 00 66 0f 1f 84 00 00 00 00 00 48 8b 10 <80> ba 90 00 00 00 01 41 83 dc ff 48 83 c0 08 48 39 c8 75 e9 48 Jul 29 13:33:13 kernel: RIP [<ffffffffc01611b3>] evergreen_bandwidth_update+0x63/0x120 [radeon] Jul 29 13:33:13 kernel: RSP <ffffc9000666bc78> Jul 29 13:33:13 kernel: CR2: 0000000000000090 Jul 29 13:33:13 kernel: ---[ end trace 84578a0022b8c1c3 ]---
Probably non-hardened related, but I cannot test with vanilla... sry
I've just tried hardened-sources-4.1.3-r3 out and it no longer shows the symptom!
Newer version no longer shows the symptom. Even CONFIG_DRM_RADEON_USERPTR is OK.