[IMA] 2.6.30-rc8 : Bug while trying to launch a KVM guest

[Sachin Sant <sachinp@in.ibm.com>]

I had a x86_64 machine running 2.6.30-rc7-git4 as a KVM Host.
I configured a KVM guest and was able to boot the guest.

On the KVM host i compiled a 2.6.30-rc8 kernel with
CONFIG_IMA=y and rebooted the machine into that kernel.

When i tried to launch the KVM guest with 2.6.30-rc8 kernel
ran into following BUG.

# qemu-system-x86_64 -hda /local/kvmtest/rhel53.img  -m 512
rhel53.img dentry_open failed
BUG: unable to handle kernel paging request at ffffffffffffffe5
IP: [<ffffffff802cde9d>] fput+0x8/0x1a
PGD 203067 PUD 204067 PMD 0 
Oops: 0002 [#2] SMP 
last sysfs file: /sys/devices/system/cpu/cpu3/cache/index2/shared_cpu_map
CPU 1 
Modules linked in: kvm_amd kvm ipv6 sr_mod cdrom fuse loop dm_mod ums_cypress
bnx2 sg mptctl i2c_piix4 rtc_cmos pcspkr usb_storage button serio_raw rtc_core
i2c_core rtc_lib shpchp k8temp pci_hotplug usbhid hid ohci_hcd ehci_hcd sd_mod
crc_t10dif usbcore edd ext3 jbd fan thermal processor thermal_sys hwmon mptsas
mptscsih mptbase scsi_transport_sas scsi_mod
Pid: 3068, comm: qemu-system-x86 Tainted: G      D    2.6.30-rc8 #1 BladeCenter
LS21 -[79716AA]-
RIP: 0010:[<ffffffff802cde9d>]  [<ffffffff802cde9d>] fput+0x8/0x1a
RSP: 0018:ffff880128d6dd88  EFLAGS: 00010282
RAX: ffffffffffffffe5 RBX: ffff880128d2a580 RCX: 0000000000000ccb
RDX: ffff88002803c000 RSI: 0000000000000046 RDI: ffffffffffffffb5
RBP: ffff880128d6dd88 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8800000be360 R11: ffff880128d6db78 R12: ffff88012db6ad60
R13: ffffffffffffffb5 R14: ffff880128d6de48 R15: ffff88012db6ac00
FS:  00007f60db16b6f0(0000) GS:ffff88002803c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffffffffffffe5 CR3: 0000000128d11000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process qemu-system-x86 (pid: 3068, threadinfo ffff880128d6c000, task
ffff88012c9f1880)
Stack:
 ffff880128d6ddc8 ffffffff803ac6f1 ffff880128d2a5a8 ffff880126805fc0
 0000000000009001 0000000000000004 ffff880128d6de48 ffff88012db6acc0
 ffff880128d6de08 ffffffff802d5f3c ffff880128d6de08 0000000000000000
Call Trace:
 [<ffffffff803ac6f1>] ima_path_check+0x1a5/0x1c3
 [<ffffffff802d5f3c>] may_open+0xc1/0x278
 [<ffffffff802d8620>] do_filp_open+0x498/0x914
 [<ffffffff802abd89>] ? handle_mm_fault+0x35b/0x75e
 [<ffffffff802cb0c9>] ? fd_install+0x30/0x60
 [<ffffffff802e0abd>] ? alloc_fd+0x6d/0x117
 [<ffffffff802cb295>] do_sys_open+0x56/0xd6
 [<ffffffff802cb33e>] sys_open+0x1b/0x1d
 [<ffffffff8020ba6b>] system_call_fastpath+0x16/0x1b
Code: ff 74 13 41 c7 87 cc 00 00 00 00 00 00 00 4c 89 ff e8 86 43 01 00 41 58
5b 41 5c 41 5d 41 5e 41 5f c9 c3 55 48 8d 47 30 48 89 e5 <f0> 48 ff 08 0f 94 c2
84 d2 74 05 e8 47 fe ff ff c9 c3 55 48 89 
RIP  [<ffffffff802cde9d>] fput+0x8/0x1a
 RSP <ffff880128d6dd88>
CR2: ffffffffffffffe5
---[ end trace 65e02cf766f19c9b ]---

Let me know if some more information is required.

Thanks
-Sachin

-- 

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Sachin Sant
IBM Linux Technology Center
India Systems and Technology Labs
Bangalore, India
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