Commit db053b86 authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge Committed by Ingo Molnar
Browse files

xen: clean up x86-64 warnings 



There are a couple of Xen features which rely on directly accessing
per-cpu data via a segment register, which is not yet available on
x86-64.  In the meantime, just disable direct access to the vcpu info
structure; this leaves some of the code as dead, but it will come to
life in time, and the warnings are suppressed.

Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 08115ab4

arch/x86/xen/enlighten.c

+10 −51
Original line number Diff line number Diff line
@@ -112,7 +112,14 @@ struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; 
 *

 * 0: not available, 1: available

 */

static int have_vcpu_info_placement = 1;

static int have_vcpu_info_placement =

#ifdef CONFIG_X86_32

	1

#else

	0

#endif

	;





static void xen_vcpu_setup(int cpu)

{
@@ -941,6 +948,7 @@ static void *xen_kmap_atomic_pte(struct page *page, enum km_type type) 
}

#endif



#ifdef CONFIG_X86_32

static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)

{

	/* If there's an existing pte, then don't allow _PAGE_RW to be set */
@@ -959,6 +967,7 @@ static __init void xen_set_pte_init(pte_t *ptep, pte_t pte) 


	xen_set_pte(ptep, pte);

}

#endif



static __init void xen_pagetable_setup_start(pgd_t *base)

{
@@ -1025,7 +1034,6 @@ void xen_setup_vcpu_info_placement(void) 


	/* xen_vcpu_setup managed to place the vcpu_info within the

	   percpu area for all cpus, so make use of it */

#ifdef CONFIG_X86_32

	if (have_vcpu_info_placement) {

		printk(KERN_INFO "Xen: using vcpu_info placement\n");
@@ -1035,7 +1043,6 @@ void xen_setup_vcpu_info_placement(void) 
		pv_irq_ops.irq_enable = xen_irq_enable_direct;

		pv_mmu_ops.read_cr2 = xen_read_cr2_direct;

	}

#endif

}



static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
@@ -1056,12 +1063,10 @@ static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf, 
	goto patch_site



	switch (type) {

#ifdef CONFIG_X86_32

		SITE(pv_irq_ops, irq_enable);

		SITE(pv_irq_ops, irq_disable);

		SITE(pv_irq_ops, save_fl);

		SITE(pv_irq_ops, restore_fl);

#endif /* CONFIG_X86_32 */

#undef SITE



	patch_site:
@@ -1399,48 +1404,11 @@ static void *m2v(phys_addr_t maddr) 
	return __ka(m2p(maddr));

}



#ifdef CONFIG_X86_64

static void walk(pgd_t *pgd, unsigned long addr)

{

	unsigned l4idx = pgd_index(addr);

	unsigned l3idx = pud_index(addr);

	unsigned l2idx = pmd_index(addr);

	unsigned l1idx = pte_index(addr);

	pgd_t l4;

	pud_t l3;

	pmd_t l2;

	pte_t l1;



	xen_raw_printk("walk %p, %lx -> %d %d %d %d\n",

		       pgd, addr, l4idx, l3idx, l2idx, l1idx);



	l4 = pgd[l4idx];

	xen_raw_printk("  l4: %016lx\n", l4.pgd);

	xen_raw_printk("      %016lx\n", pgd_val(l4));



	l3 = ((pud_t *)(m2v(l4.pgd)))[l3idx];

	xen_raw_printk("  l3: %016lx\n", l3.pud);

	xen_raw_printk("      %016lx\n", pud_val(l3));



	l2 = ((pmd_t *)(m2v(l3.pud)))[l2idx];

	xen_raw_printk("  l2: %016lx\n", l2.pmd);

	xen_raw_printk("      %016lx\n", pmd_val(l2));



	l1 = ((pte_t *)(m2v(l2.pmd)))[l1idx];

	xen_raw_printk("  l1: %016lx\n", l1.pte);

	xen_raw_printk("      %016lx\n", pte_val(l1));

}

#endif



static void set_page_prot(void *addr, pgprot_t prot)

{

	unsigned long pfn = __pa(addr) >> PAGE_SHIFT;

	pte_t pte = pfn_pte(pfn, prot);



	xen_raw_printk("addr=%p pfn=%lx mfn=%lx prot=%016llx pte=%016llx\n",

		       addr, pfn, get_phys_to_machine(pfn),

		       pgprot_val(prot), pte.pte);



	if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0))

		BUG();

}
@@ -1698,15 +1666,6 @@ asmlinkage void __init xen_start_kernel(void) 


	xen_raw_console_write("about to get started...\n");



#if 0

	xen_raw_printk("&boot_params=%p __pa(&boot_params)=%lx __va(__pa(&boot_params))=%lx\n",

		       &boot_params, __pa_symbol(&boot_params),

		       __va(__pa_symbol(&boot_params)));



	walk(pgd, &boot_params);

	walk(pgd, __va(__pa(&boot_params)));

#endif



	/* Start the world */

#ifdef CONFIG_X86_32

	i386_start_kernel();

arch/x86/xen/xen-asm_64.S

+17 −3
Original line number Diff line number Diff line
@@ -26,8 +26,15 @@ 
/* Pseudo-flag used for virtual NMI, which we don't implement yet */

#define XEN_EFLAGS_NMI	0x80000000



#if 0

#include <asm/percpu.h>

#if 1

/*

	x86-64 does not yet support direct access to percpu variables

	via a segment override, so we just need to make sure this code

	never gets used

 */

#define BUG			ud2a

#define PER_CPU_VAR(var, off)	0xdeadbeef

#endif



/*

	Enable events.  This clears the event mask and tests the pending
@@ -35,6 +42,8 @@ 
	events, then enter the hypervisor to get them handled.

 */

ENTRY(xen_irq_enable_direct)

	BUG



	/* Unmask events */

	movb $0, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
@@ -58,6 +67,8 @@ ENDPATCH(xen_irq_enable_direct) 
	non-zero.

 */

ENTRY(xen_irq_disable_direct)

	BUG



	movb $1, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)

ENDPATCH(xen_irq_disable_direct)

	ret
@@ -74,6 +85,8 @@ ENDPATCH(xen_irq_disable_direct) 
	Xen and x86 use opposite senses (mask vs enable).

 */

ENTRY(xen_save_fl_direct)

	BUG



	testb $0xff, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)

	setz %ah

	addb %ah,%ah
@@ -91,6 +104,8 @@ ENDPATCH(xen_save_fl_direct) 
	if so.

 */

ENTRY(xen_restore_fl_direct)

	BUG



	testb $X86_EFLAGS_IF>>8, %ah

	setz PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)

	/* Preempt here doesn't matter because that will deal with
@@ -133,7 +148,6 @@ check_events: 
	pop %rcx

	pop %rax

	ret

#endif



ENTRY(xen_adjust_exception_frame)

	mov 8+0(%rsp),%rcx

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