From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Peter Jones <pjones@redhat.com>
Date: Tue, 14 Aug 2018 14:07:44 -0400
Subject: [PATCH] arm/arm64 loader: Better memory allocation and error
 messages.

On mustang, our memory map looks like:

Type      Physical start  - end             #Pages        Size Attributes
reserved  0000004000000000-00000040001fffff 00000200      2MiB UC WC WT WB
conv-mem  0000004000200000-0000004393ffffff 00393e00  14654MiB UC WC WT WB
ldr-code  0000004394000000-00000043f7ffffff 00064000   1600MiB UC WC WT WB
BS-data   00000043f8000000-00000043f801ffff 00000020    128KiB UC WC WT WB
conv-mem  00000043f8020000-00000043fa15bfff 0000213c  34032KiB UC WC WT WB
ldr-code  00000043fa15c000-00000043fa2a1fff 00000146   1304KiB UC WC WT WB
ldr-data  00000043fa2a2000-00000043fa3e8fff 00000147   1308KiB UC WC WT WB
conv-mem  00000043fa3e9000-00000043fa3e9fff 00000001      4KiB UC WC WT WB
ldr-data  00000043fa3ea000-00000043fa3eafff 00000001      4KiB UC WC WT WB
ldr-code  00000043fa3eb000-00000043fa4affff 000000c5    788KiB UC WC WT WB
BS-code   00000043fa4b0000-00000043fa59ffff 000000f0    960KiB UC WC WT WB
RT-code   00000043fa5a0000-00000043fa5affff 00000010     64KiB RT UC WC WT WB
RT-data   00000043fa5b0000-00000043fa5bffff 00000010     64KiB RT UC WC WT WB
RT-code   00000043fa5c0000-00000043fa5cffff 00000010     64KiB RT UC WC WT WB
ldr-data  00000043fa5d0000-00000043fa5d0fff 00000001      4KiB UC WC WT WB
BS-code   00000043fa5d1000-00000043fa5ddfff 0000000d     52KiB UC WC WT WB
reserved  00000043fa5de000-00000043fa60ffff 00000032    200KiB UC WC WT WB
ACPI-rec  00000043fa610000-00000043fa6affff 000000a0    640KiB UC WC WT WB
ACPI-nvs  00000043fa6b0000-00000043fa6bffff 00000010     64KiB UC WC WT WB
ACPI-rec  00000043fa6c0000-00000043fa70ffff 00000050    320KiB UC WC WT WB
RT-code   00000043fa710000-00000043fa72ffff 00000020    128KiB RT UC WC WT WB
RT-data   00000043fa730000-00000043fa78ffff 00000060    384KiB RT UC WC WT WB
RT-code   00000043fa790000-00000043fa79ffff 00000010     64KiB RT UC WC WT WB
RT-data   00000043fa7a0000-00000043fa99ffff 00000200      2MiB RT UC WC WT WB
RT-code   00000043fa9a0000-00000043fa9affff 00000010     64KiB RT UC WC WT WB
RT-data   00000043fa9b0000-00000043fa9cffff 00000020    128KiB RT UC WC WT WB
BS-code   00000043fa9d0000-00000043fa9d9fff 0000000a     40KiB UC WC WT WB
reserved  00000043fa9da000-00000043fa9dbfff 00000002      8KiB UC WC WT WB
conv-mem  00000043fa9dc000-00000043fc29dfff 000018c2  25352KiB UC WC WT WB
BS-data   00000043fc29e000-00000043fc78afff 000004ed   5044KiB UC WC WT WB
conv-mem  00000043fc78b000-00000043fca01fff 00000277   2524KiB UC WC WT WB
BS-data   00000043fca02000-00000043fcea3fff 000004a2   4744KiB UC WC WT WB
conv-mem  00000043fcea4000-00000043fcea4fff 00000001      4KiB UC WC WT WB
BS-data   00000043fcea5000-00000043fd192fff 000002ee   3000KiB UC WC WT WB
conv-mem  00000043fd193000-00000043fd2b0fff 0000011e   1144KiB UC WC WT WB
BS-data   00000043fd2b1000-00000043ff80ffff 0000255f  38268KiB UC WC WT WB
BS-code   00000043ff810000-00000043ff99ffff 00000190   1600KiB UC WC WT WB
RT-code   00000043ff9a0000-00000043ff9affff 00000010     64KiB RT UC WC WT WB
conv-mem  00000043ff9b0000-00000043ff9bffff 00000010     64KiB UC WC WT WB
RT-data   00000043ff9c0000-00000043ff9effff 00000030    192KiB RT UC WC WT WB
conv-mem  00000043ff9f0000-00000043ffa05fff 00000016     88KiB UC WC WT WB
BS-data   00000043ffa06000-00000043ffffffff 000005fa   6120KiB UC WC WT WB
MMIO      0000000010510000-0000000010510fff 00000001      4KiB RT
MMIO      0000000010548000-0000000010549fff 00000002      8KiB RT
MMIO      0000000017000000-0000000017001fff 00000002      8KiB RT
MMIO      000000001c025000-000000001c025fff 00000001      4KiB RT

When we're trying to find the base of ram, if we start with GRUB_UINT_MAX
(0xffffffff on all platforms) and always use min(), that means we eventually
decide that the base of ram is GRUB_UINT_MAX, which is lower than our first
memory address, and thus our allocation of the initramfs, which specifies this
value as the maximum possible address it can be at, fails.

This patch changes it to start at GRUB_EFI_MAX_USABLE_ADDRESS, which is always
at least 0xffffffff on 32-bit platforms and at least 0x7ffffffffffffff on
64-bit platforms.  Additionally, this adds a requirement that the memory we
choose is actually /allocatable/ conventional memory, not merely
write-combining.  On this machine that means we wind up with an allocation
around 0x4392XXXXXX, which is a reasonable address.

This also changes grub_efi_allocate_pages_real() so that if 0 is allocated, it
tries to allocate again starting with the same max address it did the first
time, rather than interposing GRUB_EFI_MAX_USABLE_ADDRESS there, so that any
per-platform constraints on its given address are maintained.

Signed-off-by: Peter Jones <pjones@redhat.com>
---
 grub-core/kern/efi/mm.c        | 32 ++++++++++++-----
 grub-core/loader/arm64/linux.c | 78 ++++++++++++++++++++++++++++++++----------
 2 files changed, 82 insertions(+), 28 deletions(-)

diff --git a/grub-core/kern/efi/mm.c b/grub-core/kern/efi/mm.c
index 7692e63ba24..306924f73a4 100644
--- a/grub-core/kern/efi/mm.c
+++ b/grub-core/kern/efi/mm.c
@@ -154,6 +154,7 @@ grub_efi_allocate_pages_real (grub_efi_physical_address_t address,
 {
   grub_efi_status_t status;
   grub_efi_boot_services_t *b;
+  grub_efi_physical_address_t ret = address;
 
   /* Limit the memory access to less than 4GB for 32-bit platforms.  */
   if (address > GRUB_EFI_MAX_USABLE_ADDRESS)
@@ -165,19 +166,19 @@ grub_efi_allocate_pages_real (grub_efi_physical_address_t address,
     }
 
   b = grub_efi_system_table->boot_services;
-  status = efi_call_4 (b->allocate_pages, alloctype, memtype, pages, &address);
+  status = efi_call_4 (b->allocate_pages, alloctype, memtype, pages, &ret);
   if (status != GRUB_EFI_SUCCESS)
     {
       grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
       return NULL;
     }
 
-  if (address == 0)
+  if (ret == 0)
     {
       /* Uggh, the address 0 was allocated... This is too annoying,
 	 so reallocate another one.  */
-      address = GRUB_EFI_MAX_USABLE_ADDRESS;
-      status = efi_call_4 (b->allocate_pages, alloctype, memtype, pages, &address);
+      ret = address;
+      status = efi_call_4 (b->allocate_pages, alloctype, memtype, pages, &ret);
       grub_efi_free_pages (0, pages);
       if (status != GRUB_EFI_SUCCESS)
 	{
@@ -186,9 +187,9 @@ grub_efi_allocate_pages_real (grub_efi_physical_address_t address,
 	}
     }
 
-  grub_efi_store_alloc (address, pages);
+  grub_efi_store_alloc (ret, pages);
 
-  return (void *) ((grub_addr_t) address);
+  return (void *) ((grub_addr_t) ret);
 }
 
 void *
@@ -696,11 +697,24 @@ grub_efi_get_ram_base(grub_addr_t *base_addr)
   if (ret < 1)
     return GRUB_ERR_BUG;
 
-  for (desc = memory_map, *base_addr = GRUB_UINT_MAX;
+  for (desc = memory_map, *base_addr = GRUB_EFI_MAX_USABLE_ADDRESS;
        (grub_addr_t) desc < ((grub_addr_t) memory_map + memory_map_size);
        desc = NEXT_MEMORY_DESCRIPTOR (desc, desc_size))
-    if (desc->attribute & GRUB_EFI_MEMORY_WB)
-      *base_addr = grub_min (*base_addr, desc->physical_start);
+    {
+      if (desc->type == GRUB_EFI_CONVENTIONAL_MEMORY &&
+	  (desc->attribute & GRUB_EFI_MEMORY_WB))
+	{
+	  *base_addr = grub_min (*base_addr, desc->physical_start);
+	  grub_dprintf ("efi", "setting base_addr=0x%016lx\n", *base_addr);
+	}
+      else
+	{
+	  grub_dprintf ("efi", "ignoring address 0x%016lx\n", desc->physical_start);
+	}
+    }
+
+  if (*base_addr == GRUB_EFI_MAX_USABLE_ADDRESS)
+    grub_dprintf ("efi", "base_addr 0x%016lx is probably wrong.\n", *base_addr);
 
   grub_free(memory_map);
 
diff --git a/grub-core/loader/arm64/linux.c b/grub-core/loader/arm64/linux.c
index 93b5cd306eb..e1110749eb9 100644
--- a/grub-core/loader/arm64/linux.c
+++ b/grub-core/loader/arm64/linux.c
@@ -70,13 +70,15 @@ finalize_params_linux (void)
 {
   grub_efi_loaded_image_t *loaded_image = NULL;
   int node, retval, len;
-
+  grub_err_t err = GRUB_ERR_NONE;
   void *fdt;
 
   fdt = grub_fdt_load (0x400);
-
   if (!fdt)
-    goto failure;
+    {
+      err = grub_error(GRUB_ERR_BAD_OS, "failed to load FDT");
+      goto failure;
+    }
 
   node = grub_fdt_find_subnode (fdt, 0, "chosen");
   if (node < 0)
@@ -87,17 +89,26 @@ finalize_params_linux (void)
        */
       retval = grub_fdt_set_prop32(fdt, 0, "#address-cells", 2);
       if (retval)
-	goto failure;
+	{
+	  err = grub_error(retval, "Could not find #address-cells");
+	  goto failure;
+	}
 
       retval = grub_fdt_set_prop32(fdt, 0, "#size-cells", 2);
       if (retval)
-	goto failure;
+	{
+	  err = grub_error(retval, "Could not find #size-cells");
+	  goto failure;
+	}
 
       node = grub_fdt_add_subnode (fdt, 0, "chosen");
     }
 
   if (node < 1)
-    goto failure;
+    {
+      err = grub_error(grub_errno, "failed to load chosen fdt node.");
+      goto failure;
+    }
 
   /* Set initrd info */
   if (initrd_start && initrd_end > initrd_start)
@@ -108,15 +119,26 @@ finalize_params_linux (void)
       retval = grub_fdt_set_prop64 (fdt, node, "linux,initrd-start",
 				    initrd_start);
       if (retval)
-	goto failure;
+	{
+	  err = grub_error(retval, "Failed to set linux,initrd-start property");
+	  goto failure;
+	}
+
       retval = grub_fdt_set_prop64 (fdt, node, "linux,initrd-end",
 				    initrd_end);
       if (retval)
-	goto failure;
+	{
+	  err = grub_error(retval, "Failed to set linux,initrd-end property");
+	  goto failure;
+	}
     }
 
-  if (grub_fdt_install() != GRUB_ERR_NONE)
-    goto failure;
+  retval = grub_fdt_install();
+  if (retval != GRUB_ERR_NONE)
+    {
+      err = grub_error(retval, "Failed to install fdt");
+      goto failure;
+    }
 
   grub_dprintf ("linux", "Installed/updated FDT configuration table @ %p\n",
 		fdt);
@@ -124,14 +146,20 @@ finalize_params_linux (void)
   /* Convert command line to UCS-2 */
   loaded_image = grub_efi_get_loaded_image (grub_efi_image_handle);
   if (!loaded_image)
-    goto failure;
+    {
+      err = grub_error(grub_errno, "Failed to install fdt");
+      goto failure;
+    }
 
   loaded_image->load_options_size = len =
     (grub_strlen (linux_args) + 1) * sizeof (grub_efi_char16_t);
   loaded_image->load_options =
     grub_efi_allocate_any_pages (GRUB_EFI_BYTES_TO_PAGES (loaded_image->load_options_size));
   if (!loaded_image->load_options)
-    return grub_error(GRUB_ERR_BAD_OS, "failed to create kernel parameters");
+    {
+      err = grub_error(GRUB_ERR_BAD_OS, "failed to create kernel parameters");
+      goto failure;
+    }
 
   loaded_image->load_options_size =
     2 * grub_utf8_to_utf16 (loaded_image->load_options, len,
@@ -141,7 +169,7 @@ finalize_params_linux (void)
 
 failure:
   grub_fdt_unload();
-  return grub_error(GRUB_ERR_BAD_OS, "failed to install/update FDT");
+  return err;
 }
 
 static void
@@ -225,16 +253,28 @@ grub_linux_unload (void)
 static void *
 allocate_initrd_mem (int initrd_pages)
 {
-  grub_addr_t max_addr;
+  grub_addr_t max_addr = 0;
+  grub_err_t err;
+  void *ret;
 
-  if (grub_efi_get_ram_base (&max_addr) != GRUB_ERR_NONE)
-    return NULL;
+  err = grub_efi_get_ram_base (&max_addr);
+  if (err != GRUB_ERR_NONE)
+    {
+      grub_error (err, "grub_efi_get_ram_base() failed");
+      return NULL;
+    }
+
+  grub_dprintf ("linux", "max_addr: 0x%016lx, INITRD_MAX_ADDRESS_OFFSET: 0x%016llx\n",
+		max_addr, INITRD_MAX_ADDRESS_OFFSET);
 
   max_addr += INITRD_MAX_ADDRESS_OFFSET - 1;
+  grub_dprintf ("linux", "calling grub_efi_allocate_pages_real (0x%016lx, 0x%08x, EFI_ALLOCATE_MAX_ADDRESS, EFI_LOADER_DATA)", max_addr, initrd_pages);
 
-  return grub_efi_allocate_pages_real (max_addr, initrd_pages,
-				       GRUB_EFI_ALLOCATE_MAX_ADDRESS,
-				       GRUB_EFI_LOADER_DATA);
+  ret = grub_efi_allocate_pages_real (max_addr, initrd_pages,
+				      GRUB_EFI_ALLOCATE_MAX_ADDRESS,
+				      GRUB_EFI_LOADER_DATA);
+  grub_dprintf ("linux", "got 0x%016llx\n", (unsigned long long)ret);
+  return ret;
 }
 
 static grub_err_t
