vishmohan / vmlaunch Goto Github PK

restore_registers() is missing in init, causing Kernel Oops, 'cause the stack and registers are not clean for epilogue !

SYSENTER_ESP_MSR is 0x175
SYSENTER_EIP_MSR is 0x176

In Linux-3.2, it will hit a panic as follows,

(E1)[ 609.145249] In vmxon
(E1)[ 609.148662] VMX supported CPU.
(E4)[ 609.153040] MSR 0x3A:Lock bit is on.VMXON bit is on.OK
(E1)[ 609.159642] turned on cr4.vmxe
(E1)[ 609.164028] Doing vmlaunch now..
(E1)[ 609.168594] After vmexit
(E1)[ 609.172373] Guest VMexit reason: 0x12
(E1)[ 609.177419] Machine in vmxon: Attempting vmxoff
(E1)[ 609.183433] vmxoff complete
(E1)[ 609.187510] turned off cr4.vmxe
(E1)[ 609.191976] freeing allocated vmcs region!
(E1)[ 609.197508] freeing allocated io bitmapA region!
(E1)[ 609.203620] freeing allocated io bitmapB region!
(E1)[ 609.209731] freeing allocated msr bitmap region!
(E1)[ 609.215843] freeing allocated virtual apic page region!
(E1)[ 609.222631] freeing allocated vmxon region!
(E1)[ 609.228258] Enable Interrupts
(E1)[ 609.232531] Done
(E4)[ 609.235553] initcall 0xffff88343fc4ffff returned with preemption imbalance disabled interrupts
(E0)[ 609.246128] ------------[ cut here ]------------
(E2)[ 609.252142] kernel BUG at /var/src/linux-3.2/mm/vmalloc.c:1485!
(U0)(MSG-KERN-00005):[ 609.263094] invalid opcode: 0000 [#1] SMP
(E4)[ 609.330001] Pid: 13849, comm: insmod Tainted: P O 3.2.33 #4
(E4)[ 609.343215] RIP: 0010:[] [] vfree+0x20/0x2e
(E4)[ 609.352344] RSP: 0018:ffff8817ceeebf28 EFLAGS: 00010206
(E4)[ 609.359132] RAX: 000000000000ffff RBX: ffffffffa0068100 RCX: 0000000081000000
(E4)[ 609.367953] RDX: 0000000000000000 RSI: ffffffffa008d000 RDI: ffffffffa008d000
(E4)[ 609.376774] RBP: ffff8817ceeebf28 R08: 0000000000000000 R09: ffffffff816382a8
(E4)[ 609.385595] R10: ffff88184eeebe27 R11: 0000000000503030 R12: 0000000000000000
(E4)[ 609.394417] R13: 0000000000503030 R14: 0000000000000000 R15: 0000000000000000
(E4)[ 609.403240] FS: fffffffff9c136e0(0000) GS:ffff88343fc40000(0000) knlGS:0000000000000000
(E4)[ 609.413126] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
(E4)[ 609.420399] CR2: 00007fcbf99940f0 CR3: 0000002b3c553000 CR4: 00000000001407e0
(E4)[ 609.429219] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
(E4)[ 609.438041] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
(E4)[ 609.446865] Process insmod (pid: 13849, threadinfo ffff8817ceeea000, task ffff8817ce9d8000)
(E0)[ 609.457041] Stack:
(E4)[ 609.460151] ffff8817ceeebf38 ffffffff81068c16 ffff8817ceeebf78 ffffffff8106aa8c
(E4)[ 609.469308] 0000000000503010 000000000001ec15 0000000000000000 0000000000401cc0
(E4)[ 609.478469] 0000000000400dc0 00007fff256b79f0 00007fff256b7910 ffffffff813afb2b
(E0)[ 609.487627] Call Trace:
(E4)[ 609.491224] [] module_free+0x11/0x1e
(E4)[ 609.497911] [] sys_init_module+0x18b/0x1d0
(E4)[ 609.505179] [] system_call_fastpath+0x16/0x1b
(E0)[ 609.512732] Code: 18 4c 89 e0 5b 41 5c 41 5d c9 c3 55 48 89 e5 0f 1f 44 00 00 65 48 8b 04 25 48 b6 00 00 48 63 80 44 e0 ff ff a9

00 ff ff 07 74 02 <0f> 0b be 01 00 00 00 e8 80 fe ff ff c9 c3 55 48 89 e5 41 57 41
(U1)(MSG-KERN-00005):[ 609.535285] RIP [] vfree+0x20/0x2e
(E4)[ 609.543440] RSP
(E4)[ 609.548201] ---[ end trace 93b483d31dfc8aad ]---
(U0)(MSG-KERN-00018):[ 609.554218] Kernel panic - not syncing: Fatal exception in interrupt