xen: Support Xen pv-domains using PAT
With the dynamical mapping between cache modes and pgprot values it is
now possible to use all cache modes via the Xen hypervisor PAT settings
in a pv domain.
All to be done is to read the PAT configuration MSR and set up the
translation tables accordingly.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stefan.bader@canonical.com
Cc: xen-devel@lists.xensource.com
Cc: ville.syrjala@linux.intel.com
Cc: jbeulich@suse.com
Cc: toshi.kani@hp.com
Cc: plagnioj@jcrosoft.com
Cc: tomi.valkeinen@ti.com
Cc: bhelgaas@google.com
Link: http://lkml.kernel.org/r/1415019724-4317-19-git-send-email-jgross@suse.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index fac5e4f..6bf3a13 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1100,12 +1100,6 @@
/* Fast syscall setup is all done in hypercalls, so
these are all ignored. Stub them out here to stop
Xen console noise. */
- break;
-
- case MSR_IA32_CR_PAT:
- if (smp_processor_id() == 0)
- xen_set_pat(((u64)high << 32) | low);
- break;
default:
ret = native_write_msr_safe(msr, low, high);
@@ -1561,10 +1555,6 @@
/* Prevent unwanted bits from being set in PTEs. */
__supported_pte_mask &= ~_PAGE_GLOBAL;
-#if 0
- if (!xen_initial_domain())
-#endif
- __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
/*
* Prevent page tables from being allocated in highmem, even
@@ -1618,14 +1608,6 @@
*/
acpi_numa = -1;
#endif
-#ifdef CONFIG_X86_PAT
- /*
- * For right now disable the PAT. We should remove this once
- * git commit 8eaffa67b43e99ae581622c5133e20b0f48bcef1
- * (xen/pat: Disable PAT support for now) is reverted.
- */
- pat_enabled = 0;
-#endif
/* Don't do the full vcpu_info placement stuff until we have a
possible map and a non-dummy shared_info. */
per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
@@ -1636,6 +1618,13 @@
xen_raw_console_write("mapping kernel into physical memory\n");
xen_setup_kernel_pagetable((pgd_t *)xen_start_info->pt_base, xen_start_info->nr_pages);
+ /*
+ * Modify the cache mode translation tables to match Xen's PAT
+ * configuration.
+ */
+
+ pat_init_cache_modes();
+
/* keep using Xen gdt for now; no urgent need to change it */
#ifdef CONFIG_X86_32