FYI, we noticed the below changes on git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-misc.git x86/fsgs-4 commit ad7a085ec2a306924d317d281e8cd31a6d54b4e9 ("fixup! x86: Add support for rd/wr fs/gs base") +------------------------------------------+------------+------------+ | | 0ac0fabcd7 | ad7a085ec2 | +------------------------------------------+------------+------------+ | boot_successes | 0 | 0 | | boot_failures | 22 | 21 | | BUG:kernel_boot_crashed | 22 | 9 | | BUG:unable_to_handle_kernel | 0 | 12 | | Oops | 0 | 12 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 12 | | backtrace:native_smp_cpus_done | 0 | 10 | | backtrace:smp_init | 0 | 10 | | backtrace:kernel_init_freeable | 0 | 10 | +------------------------------------------+------------+------------+ [ 0.130317] -------------------- [ 0.130840] remote IPI: ok | [ 0.131499] local IPI: [ 0.131826] BUG: unable to handle kernel paging request at 0000000000080000 [ 0.132000] IP: [<0000000000080000>] 0x80000 [ 0.132000] PGD 0 [ 0.132000] Oops: 0010 [#1] SMP DEBUG_PAGEALLOC [ 0.132000] Modules linked in: [ 0.132000] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.0.0-wl-01084-gf699bc4 #7 [ 0.132000] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 0.132000] task: ffff880021028010 ti: ffff88002102c000 task.ti: ffff88002102c000 [ 0.132000] RIP: 0010:[<0000000000080000>] [<0000000000080000>] 0x80000 [ 0.132000] RSP: 0000:ffff880023605ef8 EFLAGS: 00010086 [ 0.132000] RAX: 0000000023600000 RBX: 0000000000000000 RCX: 00000000c0000101 [ 0.132000] RDX: 00000000ffff8800 RSI: 0000000000000400 RDI: 0000000000000830 [ 0.132000] RBP: ffff88002102fdc8 R08: 0000000000000000 R09: ffffffff845133c8 [ 0.132000] R10: 0000000000000000 R11: ffffffff853f6f00 R12: 0000000000000000 [ 0.132000] R13: 000000000000a1d6 R14: 0000000000000002 R15: 0000000000080000 [ 0.132000] FS: 0000000000000000(0000) GS:ffff880023600000(0000) knlGS:0000000000000000 [ 0.132000] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 0.132000] CR2: 0000000000080000 CR3: 0000000003e14000 CR4: 00000000000006f0 [ 0.132000] Stack: [ 0.132000] 0000000000000002 000000000000a1d6 0000000000000000 ffff88002102fdc8 [ 0.132000] 0000000000000000 ffffffff853f6f00 0000000000000000 ffffffff845133c8 [ 0.132000] 0000000000000000 0000000000000400 0000000000000830 0000000000000000 [ 0.132000] Call Trace: [ 0.132000] [ 0.132000] [] ? native_write_msr_safe+0xa/0xe [ 0.132000] [] ? native_write_msr_safe+0xa/0xe [ 0.132000] [] ? native_write_msr_safe+0xa/0xe [ 0.132000] <> [ 0.132000] [] paravirt_write_msr+0xf/0x13 [ 0.132000] [] native_x2apic_icr_write+0x12/0x14 [ 0.132000] [] __x2apic_send_IPI_mask+0xd3/0x10f [ 0.132000] [] x2apic_send_IPI_mask+0x13/0x15 [ 0.132000] [] test_nmi_ipi+0x45/0x90 [ 0.132000] [] local_ipi+0x3d/0x41 [ 0.132000] [] dotest+0x6/0x69 [ 0.132000] [] nmi_selftest+0x8f/0x16d [ 0.132000] [] native_smp_cpus_done+0x1c/0xc6 [ 0.132000] [] smp_init+0x54/0x7c [ 0.132000] [] kernel_init_freeable+0x161/0x279 [ 0.132000] [] ? rest_init+0xca/0xca [ 0.132000] [] kernel_init+0xe/0xdf [ 0.132000] [] ret_from_fork+0x58/0x90 [ 0.132000] [] ? rest_init+0xca/0xca [ 0.132000] Code: Bad RIP value. [ 0.132000] RIP [<0000000000080000>] 0x80000 [ 0.132000] RSP [ 0.132000] CR2: 0000000000080000 [ 0.132000] ---[ end trace a1ec8480cd17ab1b ]--- [ 0.132000] Kernel panic - not syncing: Fatal exception Thanks, Ying Huang