Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "The x86 updates contain:

   - A fix for a longstanding PAT bug, where PAT was reported on CPUs
     that do not support it, which leads to wrong caching attributes and
     missing MTRR updates

   - Prevent overwriting of the e820 firmware table, which causes kexec
     kernels to lose the fake mptable which is stored there.

   - Cleanup of the UV/BAU code, removing unused code and making local
     functions static"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/e820: Introduce the bootloader provided e820_table_firmware[] table
  x86/boot/e820: Rename the e820_table_firmware to e820_table_kexec
  x86/boot/e820: Avoid overwriting e820_table_firmware
  x86/mm/pat: Don't report PAT on CPUs that don't support it
  x86/platform/uv/BAU: Minor cleanup, make some local functions static

3 files changed, 45 insertions, 15 deletions

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index d78a586ba8dc..532da61d605c 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -20,10 +20,12 @@
 #include <asm/setup.h>
 
 /*
- * We organize the E820 table into two main data structures:
+ * We organize the E820 table into three main data structures:
  *
  * - 'e820_table_firmware': the original firmware version passed to us by the
- *   bootloader - not modified by the kernel. We use this to:
+ *   bootloader - not modified by the kernel. It is composed of two parts:
+ *   the first 128 E820 memory entries in boot_params.e820_table and the remaining
+ *   (if any) entries of the SETUP_E820_EXT nodes. We use this to:
  *
  *       - inform the user about the firmware's notion of memory layout
  *         via /sys/firmware/memmap
@@ -31,6 +33,14 @@
  *       - the hibernation code uses it to generate a kernel-independent MD5
  *         fingerprint of the physical memory layout of a system.
  *
+ * - 'e820_table_kexec': a slightly modified (by the kernel) firmware version
+ *   passed to us by the bootloader - the major difference between
+ *   e820_table_firmware[] and this one is that, the latter marks the setup_data
+ *   list created by the EFI boot stub as reserved, so that kexec can reuse the
+ *   setup_data information in the second kernel. Besides, e820_table_kexec[]
+ *   might also be modified by the kexec itself to fake a mptable.
+ *   We use this to:
+ *
  *       - kexec, which is a bootloader in disguise, uses the original E820
  *         layout to pass to the kexec-ed kernel. This way the original kernel
  *         can have a restricted E820 map while the kexec()-ed kexec-kernel
@@ -46,9 +56,11 @@
  * specific memory layout data during early bootup.
  */
 static struct e820_table e820_table_init		__initdata;
+static struct e820_table e820_table_kexec_init		__initdata;
 static struct e820_table e820_table_firmware_init	__initdata;
 
 struct e820_table *e820_table __refdata			= &e820_table_init;
+struct e820_table *e820_table_kexec __refdata		= &e820_table_kexec_init;
 struct e820_table *e820_table_firmware __refdata	= &e820_table_firmware_init;
 
 /* For PCI or other memory-mapped resources */
@@ -470,9 +482,9 @@ u64 __init e820__range_update(u64 start, u64 size, enum e820_type old_type, enum
 	return __e820__range_update(e820_table, start, size, old_type, new_type);
 }
 
-static u64 __init e820__range_update_firmware(u64 start, u64 size, enum e820_type old_type, enum e820_type  new_type)
+static u64 __init e820__range_update_kexec(u64 start, u64 size, enum e820_type old_type, enum e820_type  new_type)
 {
-	return __e820__range_update(e820_table_firmware, start, size, old_type, new_type);
+	return __e820__range_update(e820_table_kexec, start, size, old_type, new_type);
 }
 
 /* Remove a range of memory from the E820 table: */
@@ -546,9 +558,9 @@ void __init e820__update_table_print(void)
 	e820__print_table("modified");
 }
 
-static void __init e820__update_table_firmware(void)
+static void __init e820__update_table_kexec(void)
 {
-	e820__update_table(e820_table_firmware);
+	e820__update_table(e820_table_kexec);
 }
 
 #define MAX_GAP_END 0x100000000ull
@@ -623,7 +635,7 @@ __init void e820__setup_pci_gap(void)
 /*
  * Called late during init, in free_initmem().
  *
- * Initial e820_table and e820_table_firmware are largish __initdata arrays.
+ * Initial e820_table and e820_table_kexec are largish __initdata arrays.
  *
  * Copy them to a (usually much smaller) dynamically allocated area that is
  * sized precisely after the number of e820 entries.
@@ -643,6 +655,12 @@ __init void e820__reallocate_tables(void)
 	memcpy(n, e820_table, size);
 	e820_table = n;
 
+	size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_kexec->nr_entries;
+	n = kmalloc(size, GFP_KERNEL);
+	BUG_ON(!n);
+	memcpy(n, e820_table_kexec, size);
+	e820_table_kexec = n;
+
 	size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_firmware->nr_entries;
 	n = kmalloc(size, GFP_KERNEL);
 	BUG_ON(!n);
@@ -669,6 +687,9 @@ void __init e820__memory_setup_extended(u64 phys_addr, u32 data_len)
 	__append_e820_table(extmap, entries);
 	e820__update_table(e820_table);
 
+	memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
+	memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
+
 	early_memunmap(sdata, data_len);
 	pr_info("e820: extended physical RAM map:\n");
 	e820__print_table("extended");
@@ -727,7 +748,7 @@ core_initcall(e820__register_nvs_regions);
 /*
  * Allocate the requested number of bytes with the requsted alignment
  * and return (the physical address) to the caller. Also register this
- * range in the 'firmware' E820 table as a reserved range.
+ * range in the 'kexec' E820 table as a reserved range.
  *
  * This allows kexec to fake a new mptable, as if it came from the real
  * system.
@@ -738,9 +759,9 @@ u64 __init e820__memblock_alloc_reserved(u64 size, u64 align)
 
 	addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
 	if (addr) {
-		e820__range_update_firmware(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED);
-		pr_info("e820: update e820_table_firmware for e820__memblock_alloc_reserved()\n");
-		e820__update_table_firmware();
+		e820__range_update_kexec(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED);
+		pr_info("e820: update e820_table_kexec for e820__memblock_alloc_reserved()\n");
+		e820__update_table_kexec();
 	}
 
 	return addr;
@@ -923,13 +944,13 @@ void __init e820__reserve_setup_data(void)
 	while (pa_data) {
 		data = early_memremap(pa_data, sizeof(*data));
 		e820__range_update(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
+		e820__range_update_kexec(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
 		pa_data = data->next;
 		early_memunmap(data, sizeof(*data));
 	}
 
 	e820__update_table(e820_table);
-
-	memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
+	e820__update_table(e820_table_kexec);
 
 	pr_info("extended physical RAM map:\n");
 	e820__print_table("reserve setup_data");
@@ -1062,6 +1083,7 @@ void __init e820__reserve_resources(void)
 		res++;
 	}
 
+	/* Expose the bootloader-provided memory layout to the sysfs. */
 	for (i = 0; i < e820_table_firmware->nr_entries; i++) {
 		struct e820_entry *entry = e820_table_firmware->entries + i;
 
@@ -1175,6 +1197,7 @@ void __init e820__memory_setup(void)
 
 	who = x86_init.resources.memory_setup();
 
+	memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
 	memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
 
 	pr_info("e820: BIOS-provided physical RAM map:\n");
diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index 9d7fd5e6689a..fb095ba0c02f 100644
--- a/arch/x86/kernel/kexec-bzimage64.c
+++ b/arch/x86/kernel/kexec-bzimage64.c
@@ -100,14 +100,14 @@ static int setup_e820_entries(struct boot_params *params)
 {
 	unsigned int nr_e820_entries;
 
-	nr_e820_entries = e820_table_firmware->nr_entries;
+	nr_e820_entries = e820_table_kexec->nr_entries;
 
 	/* TODO: Pass entries more than E820_MAX_ENTRIES_ZEROPAGE in bootparams setup data */
 	if (nr_e820_entries > E820_MAX_ENTRIES_ZEROPAGE)
 		nr_e820_entries = E820_MAX_ENTRIES_ZEROPAGE;
 
 	params->e820_entries = nr_e820_entries;
-	memcpy(&params->e820_table, &e820_table_firmware->entries, nr_e820_entries*sizeof(struct e820_entry));
+	memcpy(&params->e820_table, &e820_table_kexec->entries, nr_e820_entries*sizeof(struct e820_entry));
 
 	return 0;
 }
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 65622f07e633..3486d0498800 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1076,6 +1076,13 @@ void __init setup_arch(char **cmdline_p)
 	max_possible_pfn = max_pfn;
 
 	/*
+	 * This call is required when the CPU does not support PAT. If
+	 * mtrr_bp_init() invoked it already via pat_init() the call has no
+	 * effect.
+	 */
+	init_cache_modes();
+
+	/*
 	 * Define random base addresses for memory sections after max_pfn is
 	 * defined and before each memory section base is used.
 	 */