Hi , I had a fresh box xen installed with kernel 2.6.20-1.29*.fc6xen but with this kernel guest startup will had problem and system message as below: But it didn''t had problem on kernel 2.6.18-1.2798.fc6xen Thanks kernel: CPU: 0 May 9 20:52:15 hkb2-xen3 kernel: EIP: 0061:[<c054936b>] Not tainted VLI May 9 20:52:15 hkb2-xen3 kernel: EFLAGS: 00210013 (2.6.20-1.2948.fc6xen #1) May 9 20:52:15 hkb2-xen3 kernel: EIP is at evtchn_do_upcall+0x55/0x97 May 9 20:52:15 hkb2-xen3 kernel: eax: 00000001 ebx: 00000000 ecx: d4de8fe4 edx: fffffeff May 9 20:52:15 hkb2-xen3 kernel: esi: 00000001 edi: f5416000 ebp: fffffffe esp: d4de8fc4 May 9 20:52:15 hkb2-xen3 kernel: ds: 007b es: 007b ss: 0069 May 9 20:52:15 hkb2-xen3 kernel: Process qemu-dm (pid: 4797, ti=d4de8000 task=ecb21730 task.ti=d4de8000) May 9 20:52:15 hkb2-xen3 kernel: Stack: 00000000 00000000 0000000e d4de8fac d4de8fe4 d4de8000 c0404ff2 d4de8fe4 May 9 20:52:15 hkb2-xen3 kernel: 00216402 00000073 00200246 bfd4f548 0000007b 00000000 00000000 May 9 20:52:15 hkb2-xen3 kernel: Call Trace: May 9 20:52:15 hkb2-xen3 kernel: [<c0404ff2>] hypervisor_callback+0x46/0x50 May 9 20:52:15 hkb2-xen3 kernel: ======================May 9 20:52:15 hkb2-xen3 kernel: Code: bd fe ff ff ff 88 d9 89 d8 c1 e0 05 d3 c5 89 04 24 eb 29 0f bc c0 03 04 24 8b 14 85 80 f0 6f c0 83 fa ff 74 12 8b 4c 24 1c f7 d2 <89> 51 28 89 c8 e8 40 d4 eb ff eb 05 e8 22 2e 00 00 8b 44 24 04 May 9 20:52:15 hkb2-xen3 kernel: EIP: [<c054936b>] evtchn_do_upcall+0x55/0x97 SS:ESP 0069:d4de8fc4 kernel: CPU: 1 Apr 25 15:31:53 localhost kernel: EIP: 0061:[<c04143ee>] Not tainted VLI Apr 25 15:31:53 localhost kernel: EFLAGS: 00010286 (2.6.20-1.2944.fc6xen #1) Apr 25 15:31:53 localhost kernel: EIP is at direct_remap_area_pte_fn+0x16/0x6c Apr 25 15:31:53 localhost kernel: eax: 00000000 ebx: 00000000 ecx: ee640000 edx: c15af940 Apr 25 15:31:53 localhost kernel: esi: ed7ca200 edi: c15af940 ebp: ec2ece68 esp: ec2ecdc8 Apr 25 15:31:53 localhost kernel: ds: 007b es: 007b ss: 0069 Apr 25 15:31:53 localhost gdm[3615]: gdm_slave_xioerror_handler: Fatal X error - Restarting :0 Apr 25 15:31:53 localhost kernel: Process Xorg (pid: 3616, ti=ec2ec000 task=ebf38e70 task.ti=ec2ec000) Apr 25 15:31:53 localhost kernel: Stack: 00000000 00000000 c15af940 ee640000 c045381f ec2ece68 93bca067 00000000 Apr 25 15:31:53 localhost kernel: c06e3080 c0fd6018 ee680000 ee680000 ebf38e70 ed7ca200 c1000000 c0fdab98 Apr 25 15:31:53 localhost kernel: 06fda001 00000000 00000000 000204d0 93bca067 00000000 93bca067 00000000 Apr 25 15:31:53 localhost kernel: Call Trace: Apr 25 15:31:53 localhost kernel: [<c045381f>] apply_to_page_range+0x3ed/0x45e Apr 25 15:31:53 localhost kernel: [<c0413fdf>] __direct_remap_pfn_range+0x13b/0x17d Apr 25 15:31:53 localhost kernel: [<c04143d8>] direct_remap_area_pte_fn+0x0/0x6c Apr 25 15:31:53 localhost kernel: [<c04141cb>] __ioremap+0x1aa/0x1cc Apr 25 15:31:53 localhost kernel: [<ee5cd222>] drm_addmap_core+0x1a4/0x3fd [drm] Apr 25 15:31:53 localhost kernel: [<c041766e>] __might_sleep+0x21/0xc1 Apr 25 15:31:53 localhost kernel: [<ee5cd4ee>] drm_addmap_ioctl+0x73/0xb1 [drm] Apr 25 15:31:53 localhost kernel: [<c0613625>] do_page_fault+0x767/0xc2e Apr 25 15:31:53 localhost kernel: [<ee5cd47b>] drm_addmap_ioctl+0x0/0xb1 [drm] Apr 25 15:31:53 localhost kernel: [<ee5cffda>] drm_ioctl+0x150/0x196 [drm] Apr 25 15:31:53 localhost kernel: [<c041766e>] __might_sleep+0x21/0xc1 Apr 25 15:31:53 localhost kernel: [<c047075c>] do_ioctl+0x4c/0x62 Apr 25 15:31:53 localhost kernel: [<c04709b6>] vfs_ioctl+0x244/0x256 Apr 25 15:31:53 localhost kernel: [<c0470a14>] sys_ioctl+0x4c/0x64 Apr 25 15:31:53 localhost kernel: [<c0404e3c>] syscall_call+0x7/0xb Apr 25 15:31:53 localhost kernel: ======================Apr 25 15:31:53 localhost kernel: Code: 5b 5b 5e 5f 5d e9 d7 fa ff ff 5a b8 ea ff ff ff 5b 5e 5f 5d c3 55 57 56 89 c6 53 8b 6c 24 14 83 3e 00 8b 40 04 75 04 85 c0 74 04 <0f> 0b eb fe 2b 15 84 f6 7d c0 8b 7d 00 c1 fa 05 80 3d a2 e5 72 Apr 25 15:31:53 localhost kernel: EIP: [<c04143ee>] direct_remap_area_pte_fn+0x16/0x6c SS:ESP 0069:ec2ecdc8 Apr 25 15:31:53 localhost kernel: <0>------------[ cut here ]------------ Apr 25 15:31:53 localhost kernel: kernel BUG at arch/i386/mm/hypervisor.c:197! Apr 25 15:31:53 localhost kernel: invalid opcode: 0000 [#2] Apr 25 15:31:53 localhost kernel: SMP