Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip:
  x86: Disable large pages on CPUs with Atom erratum AAE44
  x86-64: Clear a 64-bit FS/GS base on fork if selector is nonzero
  x86, mrst: Conditionally register cpu hotplug notifier for apbt
This commit is contained in:
Linus Torvalds 2010-04-28 20:41:55 -07:00
commit dfad53d48e
3 changed files with 24 additions and 3 deletions

View File

@ -429,7 +429,7 @@ static int apbt_cpuhp_notify(struct notifier_block *n,
static __init int apbt_late_init(void)
{
if (disable_apbt_percpu)
if (disable_apbt_percpu || !apb_timer_block_enabled)
return 0;
/* This notifier should be called after workqueue is ready */
hotcpu_notifier(apbt_cpuhp_notify, -20);

View File

@ -47,6 +47,27 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
(c->x86 == 0x6 && c->x86_model >= 0x0e))
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
/*
* Atom erratum AAE44/AAF40/AAG38/AAH41:
*
* A race condition between speculative fetches and invalidating
* a large page. This is worked around in microcode, but we
* need the microcode to have already been loaded... so if it is
* not, recommend a BIOS update and disable large pages.
*/
if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2) {
u32 ucode, junk;
wrmsr(MSR_IA32_UCODE_REV, 0, 0);
sync_core();
rdmsr(MSR_IA32_UCODE_REV, junk, ucode);
if (ucode < 0x20e) {
printk(KERN_WARNING "Atom PSE erratum detected, BIOS microcode update recommended\n");
clear_cpu_cap(c, X86_FEATURE_PSE);
}
}
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_SYSENTER32);
#else

View File

@ -276,12 +276,12 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
set_tsk_thread_flag(p, TIF_FORK);
p->thread.fs = me->thread.fs;
p->thread.gs = me->thread.gs;
p->thread.io_bitmap_ptr = NULL;
savesegment(gs, p->thread.gsindex);
p->thread.gs = p->thread.gsindex ? 0 : me->thread.gs;
savesegment(fs, p->thread.fsindex);
p->thread.fs = p->thread.fsindex ? 0 : me->thread.fs;
savesegment(es, p->thread.es);
savesegment(ds, p->thread.ds);