Greeting, FYI, we noticed the following commit (built with gcc-9): commit: 5da9e742d1934e86760f02caa769eecb239feafe ("[RFC][PATCH v2 12/21] x86/pti: Use PTI stack instead of trampoline stack") url: https://github.com/0day-ci/linux/commits/Alexandre-Chartre/x86-pti-Defer-... base: https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git 1fcd009102ee02e217f2e7635ab65517d785da8e in testcase: boot on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +-------------------------------------------------------+------------+------------+ | | f2df5fbe42 | 5da9e742d1 | +-------------------------------------------------------+------------+------------+ | PANIC:double_fault | 0 | 4 | | double_fault:#[##] | 0 | 4 | | Kernel_panic-not_syncing:Fatal_exception_in_interrupt | 0 | 4 | +-------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot <oliver.sang(a)intel.com&gt; [ 6.786553] Loading compiled-in X.509 certificates [ 6.788127] zswap: loaded using pool lzo/zbud [ 6.789836] Key type ._fscrypt registered [ 6.791177] Key type .fscrypt registered [ 6.792501] Key type fscrypt-provisioning registered [ 6.794677] traps: PANIC: double fault, error_code: 0x0 [ 6.794679] double fault: 0000 [#1] SMP PTI [ 6.794680] CPU: 0 PID: 87 Comm: modprobe Not tainted 5.10.0-rc1-00013-g5da9e742d193 #1 [ 6.794681] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 6.794681] RIP: 0023:0xf7fd507d [ 6.794683] Code: 8b 4c 24 04 53 56 57 55 8b 01 85 c0 75 23 8b 44 24 18 8b 5c 24 1c 8b 4c 24 20 8b 54 24 24 8b 74 24 28 8b 7c 24 2c 8b 6c 24 30 <cd> 80 5d 5f 5e 5b c3 5d 5f 5e 5b e9 30 09 00 00 65 8b 15 04 00 00 [ 6.794684] RSP: 002b:00000000fffc710c EFLAGS: 00010246 [ 6.794686] RAX: 0000000000000005 RBX: 00000000fffc7330 RCX: 0000000000088000 [ 6.794687] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 6.794688] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 6.794689] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 6.794690] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 6.794690] FS: 0000000000000000 GS: 00000000f7ff1de4 [ 6.794691] Modules linked in: [ 6.824939] ---[ end trace 2d660ddeebdfa224 ]--- [ 6.824941] RIP: 0023:0xf7fd507d [ 6.824942] Code: 8b 4c 24 04 53 56 57 55 8b 01 85 c0 75 23 8b 44 24 18 8b 5c 24 1c 8b 4c 24 20 8b 54 24 24 8b 74 24 28 8b 7c 24 2c 8b 6c 24 30 <cd> 80 5d 5f 5e 5b c3 5d 5f 5e 5b e9 30 09 00 00 65 8b 15 04 00 00 [ 6.824943] RSP: 002b:00000000fffc710c EFLAGS: 00010246 [ 6.824945] RAX: 0000000000000005 RBX: 00000000fffc7330 RCX: 0000000000088000 [ 6.824946] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 6.824947] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 6.824948] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 6.824949] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 6.824950] FS: 0000000000000000(0000) GS:ffff88823fc00000(0063) knlGS:00000000f7ff1de4 [ 6.824950] CS: 0023 DS: 002b ES: 002b CR0: 0000000080050033 [ 6.824952] CR2: ffffc9000032fff8 CR3: 000000012fd52000 CR4: 00000000000406f0 [ 6.824953] Kernel panic - not syncing: Fatal exception in interrupt [ 6.825052] Kernel Offset: disabled Kboot worker: lkp-worker11 Elapsed time: 60 To reproduce: # build kernel cd linux cp config-5.10.0-rc1-00013-g5da9e742d193 .config make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email Thanks, Oliver Sang