I was able to get some kernel messages from a qemu console: [ 208.672687] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.673786] BUG: unable to handle kernel paging request at ffffffffc054f694 [ 208.674779] #PF error: [PROT] [INSTR] [ 208.675571] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.679132] Oops: 0011 [#1] SMP PTI [ 208.680526] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.683102] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686150] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686150] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686151] #PF error: [PROT] [INSTR] [ 208.686151] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686152] Oops: 0011 [#2] SMP PTI [ 208.686153] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686153] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686154] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686154] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686154] #PF error: [PROT] [INSTR] [ 208.686154] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686156] Oops: 0011 [#3] SMP PTI [ 208.686156] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686156] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686157] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686168] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686169] #PF error: [PROT] [INSTR] [ 208.686169] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686170] Oops: 0011 [#4] SMP PTI [ 208.686170] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686170] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686171] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686171] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686171] #PF error: [PROT] [INSTR] [ 208.686171] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686172] Oops: 0011 [#5] SMP PTI [ 208.686173] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686173] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686174] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686174] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686174] #PF error: [PROT] [INSTR] [ 208.686174] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686176] Oops: 0011 [#6] SMP PTI [ 208.686176] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686176] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686177] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686177] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686177] #PF error: [PROT] [INSTR] [ 208.686177] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686178] Oops: 0011 [#7] SMP PTI [ 208.686179] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686179] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686179] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686180] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686180] #PF error: [PROT] [INSTR] [ 208.686180] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686181] Oops: 0011 [#8] SMP PTI [ 208.686182] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686182] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686182] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686183] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686183] #PF error: [PROT] [INSTR] [ 208.686183] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686184] Oops: 0011 [#9] SMP PTI [ 208.686184] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686185] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686185] BUG: stack guard page was hit at 000000002ef8e073 (stack is 00000000dd001bee..00000000b92ae6d7) [ 208.686185] kernel stack overflow (double-fault): 0000 [#10] SMP PTI [ 208.686186] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686186] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686186] RIP: 0010:rcu_irq_enter+0x5/0x70 [ 208.686187] Code: 13 48 b8 00 00 00 00 00 00 00 40 48 89 83 b0 00 00 00 eb c4 0f 0b eb e9 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1f 44 00 00 <55> 48 c7 c0 40 3a 02 00 48 89 e5 53 48 89 c3 65 48 03 1d bc b9 cf [ 208.686187] RSP: 0018:ffffb50ac0748000 EFLAGS: 00010046 [ 208.686188] RAX: 0000000000000000 RBX: ffffb50ac0748038 RCX: ffffffffb9e00a67 [ 208.686188] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb50ac0748038 [ 208.686189] RBP: ffffb50ac0748008 R08: 0000000000000000 R09: 0000000000000000 [ 208.686192] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 208.686192] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 208.686193] FS: 00007fce916b5580(0000) GS:ffffa08bfda00000(0000) knlGS:0000000000000000 [ 208.686193] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 208.686193] CR2: ffffb50ac0747ff8 CR3: 00000000732b0000 CR4: 00000000000006f0 [ 208.686193] Call Trace: [ 208.686194] ? rcu_nmi_enter+0xe/0x10 [ 208.686194] do_int3+0xea/0x120 [ 208.686194] int3+0x33/0x40 [ 208.686194] RIP: 0010:in_gate_area_no_mm+0x6/0x29 [ 208.686195] Code: a3 cb ae 01 01 74 15 48 39 35 06 56 61 01 77 0c 31 c0 48 39 35 03 56 61 01 0f 97 c0 5d c3 66 0f 1f 44 00 00 0f 1f 44 00 00 cc <31> c0 83 3d 75 cb ae 01 01 48 89 e5 74 13 48 81 e7 00 f0 ff ff 31 [ 208.686195] RSP: 0018:ffffb50ac0748118 EFLAGS: 00000002 [ 208.686196] RAX: 0000000000000000 RBX: ffffb50ac07481c1 RCX: ffffb50ac0748158 [ 208.686196] RDX: ffffb50ac0748160 RSI: ffffb50ac0748168 RDI: ffffffffc054feae [ 208.686197] RBP: ffffb50ac0748148 R08: ffffb50ac07481c1 R09: 000000000000000f [ 208.686197] R10: ffffffffba25e0c0 R11: ffffa08bfda1927b R12: ffffb50ac0748158 [ 208.686197] R13: ffffffffc054feae R14: ffffb50ac0748168 R15: ffffb50ac0748160 [ 208.686198] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 208.686198] BUG: unable to handle kernel paging request at ffffffffc054feae [ 208.686199] #PF error: [PROT] [INSTR] [ 208.686199] PGD 45a12067 P4D 45a12067 PUD 45a14067 PMD 79808067 PTE 80000000722f8061 [ 208.686200] Thread overran stack, or stack corrupted [ 208.686200] Oops: 0011 [#11] SMP PTI [ 208.686201] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686201] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686201] PANIC: double fault, error_code: 0x0 [ 208.686202] CPU: 0 PID: 3836 Comm: ftracetest Not tainted 5.0.0-26-generic #27-Ubuntu [ 208.686202] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 208.686202] RIP: 0010:vscnprintf+0x0/0x30 [ 208.686203] Code: 42 08 49 89 44 24 08 e9 58 fd ff ff 49 8b 54 24 08 48 8d 42 08 49 89 44 24 08 e9 b5 fd ff ff e8 76 d9 67 ff 66 0f 1f 44 00 00 <55> 48 89 e5 53 48 89 f3 e8 d3 fa ff ff 48 63 d0 48 39 da 73 03 5b [ 208.686203] RSP: 0018:fffffe0000006000 EFLAGS: 00010016 [ 208.686204] RAX: 00000000000016f8 RBX: ffffa08bfda18480 RCX: fffffe0000006008 [ 208.686204] RDX: ffffffffba4d51f8 RSI: 00000000000008e8 RDI: ffffa08bfda19b98 [ 208.686204] RBP: fffffe0000006050 R08: ffffa08b80000010 R09: 0000000000000000 [ 208.686205] R10: ffffffffba806a80 R11: 0000000000000000 R12: 00000000000016f8 [ 208.686205] R13: ffffffffba4d51f8 R14: ffffa08bf3080000 R15: fffffe0000006080 [ 208.686205] FS: 00007fce916b5580(0000) GS:ffffa08bfda00000(0000) knlGS:0000000000000000 [ 208.686206] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 208.686206] CR2: fffffe0000005ff8 CR3: 00000000732b0000 CR4: 00000000000006f0 [ 208.686206] Call Trace: [ 208.686207] Kernel panic - not syncing: Machine halted. [ 208.686410] Kernel Offset: 0x38200000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)