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Revert "xen PVonHVM: use E820_Reserved area for shared_info"

This reverts commit 9d02b43.

We are doing this b/c on 32-bit PVonHVM with older hypervisors
(Xen 4.1) it ends up bothing up the start_info. This is bad b/c
we use it for the time keeping, and the timekeeping code loops
forever - as the version field never changes. Olaf says to
revert it, so lets do that.

Acked-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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1 parent 5eb65be commit e9daff24a266307943457086533041bd971d0ef9 Konrad Rzeszutek Wilk committed Feb 15, 2013
Showing with 24 additions and 55 deletions.
  1. +22 −53 arch/x86/xen/enlighten.c
  2. +1 −1 arch/x86/xen/suspend.c
  3. +1 −1 arch/x86/xen/xen-ops.h
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@@ -1517,72 +1517,51 @@ asmlinkage void __init xen_start_kernel(void)
#endif
}
-#ifdef CONFIG_XEN_PVHVM
-#define HVM_SHARED_INFO_ADDR 0xFE700000UL
-static struct shared_info *xen_hvm_shared_info;
-static unsigned long xen_hvm_sip_phys;
-static int xen_major, xen_minor;
-
-static void xen_hvm_connect_shared_info(unsigned long pfn)
+void __ref xen_hvm_init_shared_info(void)
{
+ int cpu;
struct xen_add_to_physmap xatp;
+ static struct shared_info *shared_info_page = 0;
+ if (!shared_info_page)
+ shared_info_page = (struct shared_info *)
+ extend_brk(PAGE_SIZE, PAGE_SIZE);
xatp.domid = DOMID_SELF;
xatp.idx = 0;
xatp.space = XENMAPSPACE_shared_info;
- xatp.gpfn = pfn;
+ xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
BUG();
-}
-static void __init xen_hvm_set_shared_info(struct shared_info *sip)
-{
- int cpu;
-
- HYPERVISOR_shared_info = sip;
+ HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
* page, we use it in the event channel upcall and in some pvclock
* related functions. We don't need the vcpu_info placement
* optimizations because we don't use any pv_mmu or pv_irq op on
- * HVM. */
- for_each_online_cpu(cpu)
+ * HVM.
+ * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
+ * online but xen_hvm_init_shared_info is run at resume time too and
+ * in that case multiple vcpus might be online. */
+ for_each_online_cpu(cpu) {
per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
-}
-
-/* Reconnect the shared_info pfn to a (new) mfn */
-void xen_hvm_resume_shared_info(void)
-{
- xen_hvm_connect_shared_info(xen_hvm_sip_phys >> PAGE_SHIFT);
-}
-
-/* Xen tools prior to Xen 4 do not provide a E820_Reserved area for guest usage.
- * On these old tools the shared info page will be placed in E820_Ram.
- * Xen 4 provides a E820_Reserved area at 0xFC000000, and this code expects
- * that nothing is mapped up to HVM_SHARED_INFO_ADDR.
- * Xen 4.3+ provides an explicit 1MB area at HVM_SHARED_INFO_ADDR which is used
- * here for the shared info page. */
-static void __init xen_hvm_init_shared_info(void)
-{
- if (xen_major < 4) {
- xen_hvm_shared_info = extend_brk(PAGE_SIZE, PAGE_SIZE);
- xen_hvm_sip_phys = __pa(xen_hvm_shared_info);
- } else {
- xen_hvm_sip_phys = HVM_SHARED_INFO_ADDR;
- set_fixmap(FIX_PARAVIRT_BOOTMAP, xen_hvm_sip_phys);
- xen_hvm_shared_info =
- (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
}
- xen_hvm_connect_shared_info(xen_hvm_sip_phys >> PAGE_SHIFT);
- xen_hvm_set_shared_info(xen_hvm_shared_info);
}
+#ifdef CONFIG_XEN_PVHVM
static void __init init_hvm_pv_info(void)
{
+ int major, minor;
uint32_t eax, ebx, ecx, edx, pages, msr, base;
u64 pfn;
base = xen_cpuid_base();
+ cpuid(base + 1, &eax, &ebx, &ecx, &edx);
+
+ major = eax >> 16;
+ minor = eax & 0xffff;
+ printk(KERN_INFO "Xen version %d.%d.\n", major, minor);
+
cpuid(base + 2, &pages, &msr, &ecx, &edx);
pfn = __pa(hypercall_page);
@@ -1633,22 +1612,12 @@ static void __init xen_hvm_guest_init(void)
static bool __init xen_hvm_platform(void)
{
- uint32_t eax, ebx, ecx, edx, base;
-
if (xen_pv_domain())
return false;
- base = xen_cpuid_base();
- if (!base)
+ if (!xen_cpuid_base())
return false;
- cpuid(base + 1, &eax, &ebx, &ecx, &edx);
-
- xen_major = eax >> 16;
- xen_minor = eax & 0xffff;
-
- printk(KERN_INFO "Xen version %d.%d.\n", xen_major, xen_minor);
-
return true;
}
View
@@ -30,7 +30,7 @@ void xen_arch_hvm_post_suspend(int suspend_cancelled)
{
#ifdef CONFIG_XEN_PVHVM
int cpu;
- xen_hvm_resume_shared_info();
+ xen_hvm_init_shared_info();
xen_callback_vector();
xen_unplug_emulated_devices();
if (xen_feature(XENFEAT_hvm_safe_pvclock)) {
View
@@ -40,7 +40,7 @@ void xen_enable_syscall(void);
void xen_vcpu_restore(void);
void xen_callback_vector(void);
-void xen_hvm_resume_shared_info(void);
+void xen_hvm_init_shared_info(void);
void xen_unplug_emulated_devices(void);
void __init xen_build_dynamic_phys_to_machine(void);

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