lkml.org 
[lkml]   [2017]   [Dec]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 16/21] x86/entry/64: Use a per-CPU trampoline stack for IDT entries
From
Date
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?

\
 
 \ /
  Last update: 2017-12-01 18:07    [W:0.215 / U:0.040 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site