Merge tag 'for-linus-7.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - a cleanup of arch/x86/kernel/head_64.S removing the pre-built page
   tables for Xen guests

 - a small comment update

 - another cleanup for Xen PVH guests mode

 - fix an issue with Xen PV-devices backed by driver domains

* tag 'for-linus-7.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/xenbus: better handle backend crash
  xenbus: add xenbus_device parameter to xenbus_read_driver_state()
  x86/PVH: Use boot params to pass RSDP address in start_info page
  x86/xen: update outdated comment
  xen/acpi-processor: fix _CST detection using undersized evaluation buffer
  x86/xen: Build identity mapping page tables dynamically for XENPV

5 files changed, 11 insertions, 37 deletions

diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index f06e5d6a2747..ce45882ccd07 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -19,10 +19,8 @@
 extern p4d_t level4_kernel_pgt[512];
 extern p4d_t level4_ident_pgt[512];
 extern pud_t level3_kernel_pgt[512];
-extern pud_t level3_ident_pgt[512];
 extern pmd_t level2_kernel_pgt[512];
 extern pmd_t level2_fixmap_pgt[512];
-extern pmd_t level2_ident_pgt[512];
 extern pte_t level1_fixmap_pgt[512 * FIXMAP_PMD_NUM];
 extern pgd_t init_top_pgt[];
 
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 21816b48537c..85d4a5094f6b 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -616,38 +616,10 @@ SYM_DATA(early_recursion_flag, .long 0)
 
 	.data
 
-#if defined(CONFIG_XEN_PV) || defined(CONFIG_PVH)
-SYM_DATA_START_PTI_ALIGNED(init_top_pgt)
-	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC
-	.org    init_top_pgt + L4_PAGE_OFFSET*8, 0
-	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC
-	.org    init_top_pgt + L4_START_KERNEL*8, 0
-	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
-	.quad   level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC
-	.fill	PTI_USER_PGD_FILL,8,0
-SYM_DATA_END(init_top_pgt)
-
-SYM_DATA_START_PAGE_ALIGNED(level3_ident_pgt)
-	.quad	level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC
-	.fill	511, 8, 0
-SYM_DATA_END(level3_ident_pgt)
-SYM_DATA_START_PAGE_ALIGNED(level2_ident_pgt)
-	/*
-	 * Since I easily can, map the first 1G.
-	 * Don't set NX because code runs from these pages.
-	 *
-	 * Note: This sets _PAGE_GLOBAL despite whether
-	 * the CPU supports it or it is enabled.  But,
-	 * the CPU should ignore the bit.
-	 */
-	PMDS(0, __PAGE_KERNEL_IDENT_LARGE_EXEC, PTRS_PER_PMD)
-SYM_DATA_END(level2_ident_pgt)
-#else
 SYM_DATA_START_PTI_ALIGNED(init_top_pgt)
 	.fill	512,8,0
 	.fill	PTI_USER_PGD_FILL,8,0
 SYM_DATA_END(init_top_pgt)
-#endif
 
 SYM_DATA_START_PAGE_ALIGNED(level4_kernel_pgt)
 	.fill	511,8,0
diff --git a/arch/x86/platform/pvh/enlighten.c b/arch/x86/platform/pvh/enlighten.c
index 2263885d16ba..f2053cbe9b0c 100644
--- a/arch/x86/platform/pvh/enlighten.c
+++ b/arch/x86/platform/pvh/enlighten.c
@@ -25,11 +25,6 @@ struct hvm_start_info __initdata pvh_start_info;
 
 const unsigned int __initconst pvh_start_info_sz = sizeof(pvh_start_info);
 
-static u64 __init pvh_get_root_pointer(void)
-{
-	return pvh_start_info.rsdp_paddr;
-}
-
 /*
  * Xen guests are able to obtain the memory map from the hypervisor via the
  * HYPERVISOR_memory_op hypercall.
@@ -95,7 +90,7 @@ static void __init init_pvh_bootparams(bool xen_guest)
 	pvh_bootparams.hdr.version = (2 << 8) | 12;
 	pvh_bootparams.hdr.type_of_loader = ((xen_guest ? 0x9 : 0xb) << 4) | 0;
 
-	x86_init.acpi.get_root_pointer = pvh_get_root_pointer;
+	pvh_bootparams.acpi_rsdp_addr = pvh_start_info.rsdp_paddr;
 }
 
 /*
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 6e459e47cafd..eaad22b47206 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -392,7 +392,7 @@ static void __init xen_init_capabilities(void)
 
 	/*
 	 * Xen PV would need some work to support PCID: CR3 handling as well
-	 * as xen_flush_tlb_others() would need updating.
+	 * as xen_flush_tlb_multi() would need updating.
 	 */
 	setup_clear_cpu_cap(X86_FEATURE_PCID);
 
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index 3254eaa88471..c80d0058efd1 100644
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -105,6 +105,9 @@ pte_t xen_make_pte_init(pteval_t pte);
 static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss;
 #endif
 
+static pud_t level3_ident_pgt[PTRS_PER_PUD] __page_aligned_bss;
+static pmd_t level2_ident_pgt[PTRS_PER_PMD] __page_aligned_bss;
+
 /*
  * Protects atomic reservation decrease/increase against concurrent increases.
  * Also protects non-atomic updates of current_pages and balloon lists.
@@ -1777,6 +1780,12 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
 	/* Zap identity mapping */
 	init_top_pgt[0] = __pgd(0);
 
+	init_top_pgt[pgd_index(__PAGE_OFFSET_BASE_L4)].pgd =
+		__pa_symbol(level3_ident_pgt) + _KERNPG_TABLE_NOENC;
+	init_top_pgt[pgd_index(__START_KERNEL_map)].pgd =
+		__pa_symbol(level3_kernel_pgt) + _PAGE_TABLE_NOENC;
+	level3_ident_pgt[0].pud = __pa_symbol(level2_ident_pgt) + _KERNPG_TABLE_NOENC;
+
 	/* Pre-constructed entries are in pfn, so convert to mfn */
 	/* L4[273] -> level3_ident_pgt  */
 	/* L4[511] -> level3_kernel_pgt */