Greetings, I got the below dmesg and the first bad commit is commit 57fa4af0635d30b2061377aab87094762fbc3373 Author: Kees Cook Date: Tue Apr 23 17:18:38 2013 -0700 x86: kaslr: select random base offset Select a random location when CONFIG_RANDOMIZE_BASE is used, bounded by CONFIG_RANDOMIZE_BASE_MAX_OFFSET. Sources of randomness currently include RDRAND, RDTSC, or the i8254. Signed-off-by: Kees Cook --- v3: - fall back to reading the i8254 when no TSC, suggested by HPA. v2: - use rdtscl from msr.h, thanks to Mathias Krause. [ 1.402214] Initramfs unpacking failed: junk in compressed archive [ 1.405745] Freeing initrd memory: 23656k freed [ 1.407846] BUG: unable to handle kernel paging request at ffff88000e8d6000 [ 1.410031] IP: [] free_init_pages+0xf1/0x14d [ 1.410031] PGD f550067 PUD f551067 PMD c1c6063 PTE 800000000e8d6161 [ 1.410031] Oops: 0003 [#1] [ 1.410031] Modules linked in: [ 1.410031] CPU: 0 PID: 1 Comm: swapper Not tainted 3.10.0-rc7-00012-g728c681 #3 [ 1.410031] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 1.410031] task: ffff88000d0b8000 ti: ffff88000d0b2000 task.ti: ffff88000d0b2000 [ 1.410031] RIP: 0010:[] [] free_init_pages+0xf1/0x14d [ 1.410031] RSP: 0000:ffff88000d0b3e78 EFLAGS: 00010202 [ 1.410031] RAX: 00000000cccccccc RBX: ffff88000e8d6000 RCX: 0000000000000400 [ 1.410031] RDX: ffff88000d0b3fd8 RSI: 0000000000000006 RDI: ffff88000e8d6000 [ 1.410031] RBP: ffff88000d0b3ea8 R08: 0000000000000000 R09: ffffffff8e8bd7b0 [ 1.410031] R10: ffffffff8e8bd7b0 R11: ffffffff8e8bd7b0 R12: ffff88000fff0000 [ 1.410031] R13: ffffea0000000000 R14: ffffffff8eba3398 R15: 000000000000171a [ 1.410031] FS: 0000000000000000(0000) GS:ffffffff8ee28000(0000) knlGS:0000000000000000 [ 1.410031] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1.410031] CR2: ffff88000e8d6000 CR3: 000000000ee10000 CR4: 00000000000006f0 [ 1.410031] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1.410031] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 1.410031] Stack: [ 1.410031] 0000000000000000 ffffffff8f0e4dde ffffffff8f1b57c0 0000000000000000 [ 1.410031] 0000000000000000 0000000000000000 ffff88000d0b3eb8 ffffffff8f0fa870 [ 1.410031] ffff88000d0b3ec8 ffffffff8f0e4eab ffff88000d0b3ef8 ffffffff8e0002c3 [ 1.410031] Call Trace: [ 1.410031] [] ? unpack_to_rootfs+0x33b/0x33b [ 1.410031] [] free_initrd_mem+0x28/0x31 [ 1.410031] [] populate_rootfs+0xcd/0x101 [ 1.410031] [] do_one_initcall+0xe8/0x1c5 [ 1.410031] [] kernel_init_freeable+0x1a5/0x2ac [ 1.410031] [] ? loglevel+0x46/0x46 [ 1.410031] [] ? rest_init+0xd4/0xd4 [ 1.410031] [] kernel_init+0x15/0x176 [ 1.410031] [] ret_from_fork+0x7a/0xb0 [ 1.410031] [] ? rest_init+0xd4/0xd4 [ 1.410031] Code: c0 e8 e0 c6 69 00 48 ff 05 2f aa 1e 01 49 bd 00 00 00 00 00 ea ff ff 48 ff 05 3e aa 1e 01 b9 00 04 00 00 b8 cc cc cc cc 48 89 df ab 48 89 df e8 c6 66 00 00 48 ff 05 08 aa 1e 01 48 c1 e8 0c [ 1.410031] RIP [] free_init_pages+0xf1/0x14d [ 1.410031] RSP [ 1.410031] CR2: ffff88000e8d6000 [ 1.410031] ---[ end trace 960e7beaae8e44f3 ]--- git bisect start 728c681783a8e0b8a0dc5df440503c51bbaa9789 9e895ace5d82df8929b16f58e9f515f6d54ab82d -- git bisect bad 76bf0e2ad9dacf346f861d13764ef4e3ed10e310 # 13:56 27- x86: kaslr: report kernel offset on panic git bisect good a6c21a0b3185bcc54996819157735398140a674f # 14:23 160+ x86: kaslr: return location from decompress_kernel git bisect bad c1babe7ec300af293cf2716f037a935e6bb81a94 # 14:29 48- x86: kaslr: select memory region from e820 maps git bisect bad 57fa4af0635d30b2061377aab87094762fbc3373 # 14:33 11- x86: kaslr: select random base offset git bisect good a6c21a0b3185bcc54996819157735398140a674f # 14:49 480+ x86: kaslr: return location from decompress_kernel git bisect bad 728c681783a8e0b8a0dc5df440503c51bbaa9789 # 14:49 0- Merge remote-tracking branch 'kees/strncpy-strlen' into devel-hive-x86_64-201306231236 git bisect good 9e895ace5d82df8929b16f58e9f515f6d54ab82d # 15:23 480+ Linux 3.10-rc7 git bisect good e1a86578747376f08985627c84df088a5d0d1e92 # 16:13 480+ Add linux-next specific files for 20130621 Thanks, Fengguang