On 11/27/2017 02:45 AM, Ingo Molnar wrote: > --- a/arch/x86/kernel/cpu/common.c > +++ b/arch/x86/kernel/cpu/common.c > @@ -1645,11 +1645,13 @@ void cpu_init(void) > setup_cpu_entry_area(cpu); > > /* > - * Initialize the TSS. Don't bother initializing sp0, as the initial > - * task never enters user mode. > + * Initialize the TSS. sp0 points to the entry trampoline stack > + * regardless of what task is running. > */ > set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss); > load_TR_desc(); > + load_sp0((unsigned long)&get_cpu_entry_area(cpu)->tss + > + offsetofend(struct tss_struct, SYSENTER_stack)); > > load_mm_ldt(&init_mm);
Does this also mean that our stack dumps will say "<SYSENTER>" in oopses? > [ 30.811750] CR2: fffffffffdeb2f98 CR3: 0000000423fae001 CR4: > 00000000001607e0 > > [ 30.819712] Call Trace: > > > [ 30.822442] <SYSENTER> > > > [ 30.825170] trace_hardirqs_on_thunk+0x1c/0x1c > > ... > [ 31.000571] R13: 0000000000000050 R14: 0000000000000076 R15: > 00007f59f76f2d60 > > [ 31.008533] </SYSENTER> > Should we change that string to something more descriptive?