lkml.org 
[lkml]   [2008]   [Jul]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [crash, bisected] Re: [PATCH 3/4] x86_64: Fold pda into per cpu area
Jeremy Fitzhardinge wrote:
...
> Last time it was doing this, it was a result of a triple-fault caused by
> loading %ds with an all-zero gdt. I modified Xen to dump the CPU state
> on triple-faults, so it was easy to pinpoint. I can do that again if it
> helps.
>
> J

Hi Jeremy,

There are two question marks for my patchset. The first is in

arch/x86/xen/smp.c:xen_cpu_up()

287 #ifdef CONFIG_X86_64
288 /* Allocate node local memory for AP pdas */
289 WARN_ON(cpu == 0);
290 if (cpu > 0) {
291 rc = get_local_pda(cpu);
292 if (rc)
293 return rc;
294 }
295 #endif

and the second is at:

arch/x86/xen/enlighten.c:xen_start_kernel()

1748 #ifdef CONFIG_X86_64
1749 /* Disable until direct per-cpu data access. */
1750 have_vcpu_info_placement = 0;
1751 x86_64_init_pda();
1752 #endif

I believe with the pda folded into the percpu area, get_local_pda()
and x86_64_init_pda() have been removed, so these are no longer
required, yes?

Also, arch/x86/kernel/acpi/sleep.c:acpi_save_state_mem() sets up
the startup code address with:

102 initial_code = (unsigned long)wakeup_long64;
103 saved_magic = 0x123456789abcdef0;

Should the pda and gdt_page address also be setup as is done in
smpboot.c:do_boot_cpu():

(CONFIG_X86_64)
801 initial_pda = (unsigned long)get_cpu_pda(cpu);
802 #endif
803 early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
804 initial_code = (unsigned long)start_secondary;


Thanks!
Mike


\
 
 \ /
  Last update: 2008-07-25 22:09    [W:0.168 / U:0.628 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site