I just ran my ftrace test suite against v5.19-rc7 to see if anything pops up. And one of my boot tests failed with: [ 2.459713] Last level iTLB entries: 4KB 1024, 2MB 1024, 4MB 1024 [ 2.460712] Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 1024, 1GB 4 [ 2.461712] Spectre V1 : Mitigation: usercopy/swapgs barriers and __user pointer sanitization [ 2.462713] Spectre V2 : Mitigation: Retpolines [ 2.464712] Spectre V2 : Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch [ 2.465712] Speculative Store Bypass: Vulnerable [ 2.466713] MDS: Vulnerable: Clear CPU buffers attempted, no microcode [ 2.467712] SRBDS: Vulnerable: No microcode [ 2.488002] ------------[ cut here ]------------ [ 2.488712] WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:558 apply_returns+0xa3/0x1ec [ 2.489712] Modules linked in: [ 2.490712] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc7-test #65 [ 2.491712] Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014 [ 2.492712] RIP: 0010:apply_returns+0xa3/0x1ec [ 2.493712] Code: 0f b6 5d a2 48 63 45 88 48 01 c3 4c 01 e3 48 89 da 4c 89 e7 e8 c2 25 00 00 84 c0 0f 85 1f 01 00 00 48 81 fb c0 49 40 a1 74 07 <0f> 0b e9 0f 01 00 00 83 3d a1 83 4f 02 00 74 24 0f b6 55 a2 48 63 [ 2.494712] RSP: 0000:ffffffffa1e03df0 EFLAGS: 00010206 [ 2.495711] RAX: 0000000000000000 RBX: ffffffffa173e8ad RCX: 0000000000000001 [ 2.496711] RDX: 0000000000000003 RSI: ffffffffa161b20c RDI: ffffffffa173e8ad [ 2.497711] RBP: ffffffffa1e03ea8 R08: 00000000fffffff1 R09: 000000000000000f [ 2.498711] R10: ffffffffa1e03db8 R11: 0000000000000b03 R12: ffffffffa173e8a8 [ 2.499711] R13: ffffffffa2550d30 R14: 0000000000000000 R15: ffffffffa1e32138 [ 2.500712] FS: 0000000000000000(0000) GS:ffff8e8796400000(0000) knlGS:0000000000000000 [ 2.501711] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.502711] CR2: ffff8e879edff000 CR3: 0000000014e2a001 CR4: 00000000001706f0 [ 2.503712] Call Trace: [ 2.504712] [ 2.505721] alternative_instructions+0x39/0xe9 [ 2.506712] check_bugs+0x310/0x330 [ 2.507712] start_kernel+0x605/0x63e [ 2.508715] x86_64_start_reservations+0x24/0x2a [ 2.509712] x86_64_start_kernel+0x8d/0x97 [ 2.510713] secondary_startup_64_no_verify+0xe0/0xeb [ 2.511719] [ 2.512712] irq event stamp: 142170 [ 2.513711] hardirqs last enabled at (142180): [] __up_console_sem+0x4b/0x53 [ 2.514711] hardirqs last disabled at (142189): [] __up_console_sem+0x2b/0x53 [ 2.515712] softirqs last enabled at (8013): [] __do_softirq+0x389/0x3c8 [ 2.516711] softirqs last disabled at (8006): [] __irq_exit_rcu+0x72/0xcb [ 2.517711] ---[ end trace 0000000000000000 ]--- [ 2.529074] Freeing SMP alternatives memory: 44K [ 2.633924] smpboot: CPU0: Intel(R) Core(TM) i3-4130 CPU @ 3.40GHz (family: 0x6, model: 0x3c, stepping: 0x3) [ 2.636420] cblist_init_generic: Setting adjustable number of callback queues. [ 2.636712] cblist_init_generic: Setting shift to 2 and lim to 1. [ 2.637821] cblist_init_generic: Setting shift to 2 and lim to 1. [ 2.638822] Running RCU-tasks wait API self tests [ 2.742759] Performance Events: PEBS fmt2+, Haswell events, 16-deep LBR, full-width counters, Intel PMU driver. [ 2.743718] ... version: 3 [ 2.744712] ... bit width: 48 [ 2.745712] ... generic registers: 4 [ 2.746712] ... value mask: 0000ffffffffffff [ 2.747712] ... max period: 00007fffffffffff [ 2.748712] ... fixed-purpose events: 3 [ 2.749712] ... event mask: 000000070000000f [ 2.751038] Estimated ratio of average max frequency by base frequency (times 1024): 1024 [ 2.751848] rcu: Hierarchical SRCU implementation. [ 2.755405] smp: Bringing up secondary CPUs ... [ 2.756470] x86: Booting SMP configuration: [ 2.757713] .... node #0, CPUs: #1 [ 1.309155] numa_add_cpu cpu 1 node 0: mask now 0-1 [ 2.767842] #2 [ 1.309155] numa_add_cpu cpu 2 node 0: mask now 0-2 [ 2.774816] MDS CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details. [ 2.777343] #3 [ 1.309155] numa_add_cpu cpu 3 node 0: mask now 0-3 [ 2.784230] smp: Brought up 1 node, 4 CPUs [ 2.784713] smpboot: Max logical packages: 1 Attached is the config. -- Steve