Hi Joe, FYI. Here is another bisect result. commit eea0e9cbb9e65cd553d302a4aefd4c7b70d9fd90 Author: Joe Mario Date: Wed Oct 23 15:06:53 2013 +0200 kbuild: Increase kallsyms max symbol length [AK: This seems like a ticking time bomb even without LTO, so should be merged now. It causes very weird problems. Thanks to Joe for tracking them down.] With the added postfixes that LTO adds for local symbols, the longest name in the kernel overflows the namebuf[KSYM_NAME_LEN] array by two bytes. That name is: __pci_fixup_resumePCI_VENDOR_ID_SERVERWORKSPCI_DEVICE_ID_SERVERWORKS_HT1000SBquirk_disable_broadcom_boot_interrupt.1488004.672802 Double the max symbol name length. v2: Use 255 (Joe Perches) Signed-off-by: Andi Kleen Signed-off-by: Michal Marek +--------------------------------------------------+----+ | | | +--------------------------------------------------+----+ | has_kernel_error_warning | 19 | | general_protection_fault:PREEMPT_DEBUG_PAGEALLOC | 19 | | Kernel_panic-not_syncing:Fatal_exception | 19 | +--------------------------------------------------+----+ [ 1.163196] AVX instructions are not detected. [ 1.164640] AVX instructions are not detected. [ 1.168708] Initializing RT-Tester: OK [ 1.202823] general protection fault: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [ 1.204010] Modules linked in: [ 1.204010] CPU: 0 PID: 1 Comm: swapper Not tainted 3.12.0-02415-g65a52a4e #73 [ 1.204010] task: ffff88000ec64040 ti: ffff88000ec66000 task.ti: ffff88000ec66000 [ 1.204010] RIP: 0010:[] [] kernel_init_freeable+0x140/0x1d3 [ 1.204010] RSP: 0000:ffff88000ec67f18 EFLAGS: 00010287 [ 1.204010] RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000000000 [ 1.204010] RDX: 0000000000000000 RSI: ffffffff81888590 RDI: ffffffff8188b5d8 [ 1.204010] RBP: ffff88000ec67f38 R08: 0000000000000000 R09: 0000000000000000 [ 1.204010] R10: 0000000000000000 R11: 0000000000000000 R12: ff00ffff819e2a98 [ 1.204010] R13: 000000000000017c R14: 0000000000000000 R15: 0000000000000000 [ 1.204010] FS: 0000000000000000(0000) GS:ffffffff8185b000(0000) knlGS:0000000000000000 [ 1.204010] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1.204010] CR2: 0000000000000000 CR3: 000000000184b000 CR4: 00000000000006b0 [ 1.204010] Stack: [ 1.204010] ffffffff819416a3 ffffffff814f1d68 0000000000000000 0000000000000000 [ 1.204010] ffff88000ec67f48 ffffffff814f1d71 0000000000000000 ffffffff81505b8a [ 1.204010] 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 1.204010] Call Trace: [ 1.204010] [] ? do_early_param+0x88/0x88 [ 1.204010] [] ? rest_init+0xbc/0xbc [ 1.204010] [] kernel_init+0x9/0xcc [ 1.204010] [] ret_from_fork+0x7a/0xb0 [ 1.204010] [] ? rest_init+0xbc/0xbc [ 1.204010] Code: 81 41 89 d9 41 89 d8 44 89 e9 48 c7 c2 f8 74 83 81 48 89 c6 e8 9f 95 73 ff 4c 8b 24 dd 60 08 9c 81 4c 3b 24 dd 68 08 9c 81 73 0f <49> 8b 3c 24 49 83 c4 08 e8 44 e3 6b ff eb e7 48 ff c3 eb 96 e8 [ 1.204010] RIP [] kernel_init_freeable+0x140/0x1d3 [ 1.204010] RSP [ 1.258402] ---[ end trace 034c5e9620a58ceb ]--- [ 1.259754] Kernel panic - not syncing: Fatal exception git bisect start 65a52a4ea1f334e61fe0178fc2a87c3f3e5c62a8 5e01dc7b26d9f24f39abace5da98ccbd6a5ceb52 -- git bisect good ba275241030cfe87b87d6592345c7e7ebd9b6fba # 11:49 20+ 0 virtio-net: coalesce rx frags when possible during rx git bisect good 24d70dca6f3c9261aa9cf85252b02e4044ea0822 # 11:57 20+ 0 Merge remote-tracking branch 'drm-upstream/drm-next' into drm-intel-nightly git bisect good 1e7d30355d91c70e2557daf3dac633255202d2df # 12:15 20+ 0 rt2x00: rt2800pci: split rt2800pci_enable_radio function git bisect bad eed5e6cb394511c3324b88a25da8cef7938b3e30 # 12:28 0- 4 Merge 'bluetooth/master' into devel-xian-x86_64-201311081746 git bisect good 7751ef1b3184ecfaebc5e5a8981407814ce0be0b # 12:39 20+ 0 Bluetooth: Check for flag instead of features in update_scan_rsp_data() git bisect bad 37d1c5fc2dd80db8c084e5c3d324cb92dd6e5a94 # 12:44 0- 2 Merge branches 'kbuild/kbuild' and 'kbuild/misc' into kbuild/for-next git bisect good 32f1b13973cc51c7ee96bf10343391f16a2de761 # 12:52 20+ 0 Merge v3.12-rc1 into kbuild/for-next git bisect good e125096e733e966e055ee6033169f68233f9bf9c # 12:59 20+ 0 Merge branch 'yem/kconfig-for-next' of git://gitorious.org/linux-kconfig/linux-kconfig into kbuild/kconfig git bisect good 86dd0b57e56d1db84a18761819aab80f2e6734f5 # 13:25 20+ 0 Merge branches 'kbuild/kbuild' and 'kbuild/misc' into kbuild/for-next git bisect bad 21cf6e584ce35b79374581e6344dd7c74f8b4a2b # 13:28 0- 1 kbuild, bloat-o-meter: fix static detection git bisect bad f3462aa952cfc8f4b095103cb9b3d306dd216558 # 13:30 0- 1 Kbuild: Handle longer symbols in kallsyms.c git bisect bad eea0e9cbb9e65cd553d302a4aefd4c7b70d9fd90 # 13:36 0- 1 kbuild: Increase kallsyms max symbol length git bisect good 80970472179a45609c0b11b80619bc8c32b15f77 # 14:25 60+ 0 Makefile: enable -Werror=implicit-int and -Werror=strict-prototypes by default git bisect bad 65a52a4ea1f334e61fe0178fc2a87c3f3e5c62a8 # 14:25 0- 19 Merge 'drm-intel/drm-intel-nightly' into devel-xian-x86_64-201311081746 git bisect good 4364aab74a616ea2c94951bcff0290db74f49fac # 14:51 60+ 0 Revert "kbuild: Increase kallsyms max symbol length" git bisect good 6c86ae2928f9e4cbf0d5844f5fcfd549e3450b8c # 15:07 60+ 0 Merge tag 'ftrace-urgent-3.12-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace git bisect good bad570d77024cba808126d68a2072f6f8ce64c27 # 15:30 60+ 60 Add linux-next specific files for 20131108 Thanks, Fengguang