3 files changed, 29 insertions, 7 deletions

diff --git a/arch/x86/include/asm/e820/api.h b/arch/x86/include/asm/e820/api.h
index a688095421ab..a504adc661a4 100644
--- a/arch/x86/include/asm/e820/api.h
+++ b/arch/x86/include/asm/e820/api.h
@@ -5,6 +5,7 @@
 
 extern struct e820_table *e820_table;
 extern struct e820_table *e820_table_kexec;
+extern struct e820_table *e820_table_firmware;
 
 extern unsigned long pci_mem_start;
 
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 591019031e23..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_kexec': the original firmware version passed to us by the
- *   bootloader - not modified by the kernel. We use this to:
+ * - 'e820_table_firmware': the original firmware version passed to us by the
+ *   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
@@ -47,9 +57,11 @@
  */
 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 */
 unsigned long pci_mem_start = 0xaeedbabe;
@@ -648,6 +660,12 @@ __init void e820__reallocate_tables(void)
         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);
+        memcpy(n, e820_table_firmware, size);
+        e820_table_firmware = n;
 }
 
 /*
@@ -670,6 +688,7 @@ void __init e820__memory_setup_extended(u64 phys_addr, u32 data_len)
         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");
@@ -1064,8 +1083,9 @@ void __init e820__reserve_resources(void)
                 res++;
         }
 
-        for (i = 0; i < e820_table_kexec->nr_entries; i++) {
-                struct e820_entry *entry = e820_table_kexec->entries + i;
+        /* 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;
 
                 firmware_map_add_early(entry->addr, entry->addr + entry->size, e820_type_to_string(entry));
         }
@@ -1178,6 +1198,7 @@ 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");
         e820__print_table(who);
diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c
index 3ba161a08d6e..e3e62c8a8e70 100644
--- a/arch/x86/power/hibernate_64.c
+++ b/arch/x86/power/hibernate_64.c
@@ -251,7 +251,7 @@ static int get_e820_md5(struct e820_table *table, void *buf)
 
 static void hibernation_e820_save(void *buf)
 {
-        get_e820_md5(e820_table_kexec, buf);
+        get_e820_md5(e820_table_firmware, buf);
 }
 
 static bool hibernation_e820_mismatch(void *buf)
@@ -264,7 +264,7 @@ static bool hibernation_e820_mismatch(void *buf)
         if (!memcmp(result, buf, MD5_DIGEST_SIZE))
                 return false;
 
-        ret = get_e820_md5(e820_table_kexec, result);
+        ret = get_e820_md5(e820_table_firmware, result);
         if (ret)
                 return true;