Commit 2e8fe719 authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge Committed by Ingo Molnar
Browse files

xen: fix UP setup of shared_info 



We need to set up the shared_info pointer once we've mapped the real
shared_info into its fixmap slot.  That needs to happen once the general
pagetable setup has been done.  Previously, the UP shared_info was set
up one in xen_start_kernel, but that was left pointing to the dummy
shared info.  Unfortunately there's no really good place to do a later
setup of the shared_info in UP, so just do it once the pagetable setup
has been done.

[ Stable: needed in 2.6.24.x ]

Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 04c44a08

arch/x86/xen/enlighten.c

+25 −20
Original line number Diff line number Diff line
@@ -103,6 +103,7 @@ static void __init xen_vcpu_setup(int cpu) 
	int err;

	struct vcpu_info *vcpup;



	BUG_ON(HYPERVISOR_shared_info == &dummy_shared_info);

	per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];



	if (!have_vcpu_info_placement)
@@ -805,33 +806,43 @@ static __init void xen_pagetable_setup_start(pgd_t *base) 
			  PFN_DOWN(__pa(xen_start_info->pt_base)));

}



static __init void xen_pagetable_setup_done(pgd_t *base)

static __init void setup_shared_info(void)

{

	/* This will work as long as patching hasn't happened yet

	   (which it hasn't) */

	pv_mmu_ops.alloc_pt = xen_alloc_pt;

	pv_mmu_ops.alloc_pd = xen_alloc_pd;

	pv_mmu_ops.release_pt = xen_release_pt;

	pv_mmu_ops.release_pd = xen_release_pt;

	pv_mmu_ops.set_pte = xen_set_pte;



	if (!xen_feature(XENFEAT_auto_translated_physmap)) {

		unsigned long addr = fix_to_virt(FIX_PARAVIRT_BOOTMAP);



		/*

		 * Create a mapping for the shared info page.

		 * Should be set_fixmap(), but shared_info is a machine

		 * address with no corresponding pseudo-phys address.

		 */

		set_pte_mfn(fix_to_virt(FIX_PARAVIRT_BOOTMAP),

		set_pte_mfn(addr,

			    PFN_DOWN(xen_start_info->shared_info),

			    PAGE_KERNEL);



		HYPERVISOR_shared_info =

			(struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);



		HYPERVISOR_shared_info = (struct shared_info *)addr;

	} else

		HYPERVISOR_shared_info =

			(struct shared_info *)__va(xen_start_info->shared_info);



#ifndef CONFIG_SMP

	/* In UP this is as good a place as any to set up shared info */

	xen_setup_vcpu_info_placement();

#endif

}



static __init void xen_pagetable_setup_done(pgd_t *base)

{

	/* This will work as long as patching hasn't happened yet

	   (which it hasn't) */

	pv_mmu_ops.alloc_pt = xen_alloc_pt;

	pv_mmu_ops.alloc_pd = xen_alloc_pd;

	pv_mmu_ops.release_pt = xen_release_pt;

	pv_mmu_ops.release_pd = xen_release_pt;

	pv_mmu_ops.set_pte = xen_set_pte;



	setup_shared_info();



	/* Actually pin the pagetable down, but we can't set PG_pinned

	   yet because the page structures don't exist yet. */

	{
@@ -1182,15 +1193,9 @@ asmlinkage void __init xen_start_kernel(void) 
	x86_write_percpu(xen_cr3, __pa(pgd));

	x86_write_percpu(xen_current_cr3, __pa(pgd));



#ifdef CONFIG_SMP

	/* Don't do the full vcpu_info placement stuff until we have a

	   possible map. */

	   possible map and a non-dummy shared_info. */

	per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];

#else

	/* May as well do it now, since there's no good time to call

	   it later on UP. */

	xen_setup_vcpu_info_placement();

#endif



	pv_info.kernel_rpl = 1;

	if (xen_feature(XENFEAT_supervisor_mode_kernel))

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