On 01/17/17 at 05:13pm, Ard Biesheuvel wrote:

On 16 January 2017 at 02:45, Dave Young [off-list ref] wrote:

quoted

efi_mem_reserve cares only about boot services regions, for making sure
later efi_free_boot_services does not free areas which are still useful,
such as bgrt image buffer.

So add a new argument to efi_memmap_insert for this purpose.

So what happens is we try to efi_mem_reserve() a regions that is not
bootservices code or data? We shouldn't simply ignore it, because it
is a serious condition.

efi_mem_reserve is designed to address the boot service memory reservation
issue but I'm not sure if we could have other requirement in the future,
then the efi_mem_reserve itself at least the function comment need an
update also. Anyway I have no strong opinion about this patch..

quoted

Signed-off-by: Dave Young <redacted>
---
v1->v2: only check EFI_BOOT_SERVICES_CODE/_DATA
 arch/x86/platform/efi/quirks.c  |    2 +-
 drivers/firmware/efi/fake_mem.c |    3 ++-
 drivers/firmware/efi/memmap.c   |    6 +++++-
 include/linux/efi.h             |    4 ++--
 4 files changed, 10 insertions(+), 5 deletions(-)

--- linux-x86.orig/drivers/firmware/efi/memmap.c
+++ linux-x86/drivers/firmware/efi/memmap.c

@@ -229,7 +229,7 @@ int __init efi_memmap_split_count(efi_me
  * to see how large @buf needs to be.
  */
 void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf,
-                             struct efi_mem_range *mem)
+                             struct efi_mem_range *mem, bool boot_only)
 {
        u64 m_start, m_end, m_attr;
        efi_memory_desc_t *md;

@@ -262,6 +262,10 @@ void __init efi_memmap_insert(struct efi
                start = md->phys_addr;
                end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;

+               if (boot_only && !(md->type == EFI_BOOT_SERVICES_CODE ||
+                                  md->type == EFI_BOOT_SERVICES_DATA))
+                       continue;
+
                if (m_start <= start && end <= m_end)
                        md->attribute |= m_attr;

--- linux-x86.orig/arch/x86/platform/efi/quirks.c
+++ linux-x86/arch/x86/platform/efi/quirks.c

@@ -226,7 +226,7 @@ void __init efi_arch_mem_reserve(phys_ad
                return;
        }

-       efi_memmap_insert(&efi.memmap, new, &mr);
+       efi_memmap_insert(&efi.memmap, new, &mr, true);
        early_memunmap(new, new_size);

        efi_memmap_install(new_phys, num_entries);
--- linux-x86.orig/drivers/firmware/efi/fake_mem.c
+++ linux-x86/drivers/firmware/efi/fake_mem.c

@@ -85,7 +85,8 @@ void __init efi_fake_memmap(void)
        }

        for (i = 0; i < nr_fake_mem; i++)
-               efi_memmap_insert(&efi.memmap, new_memmap, &fake_mems[i]);
+               efi_memmap_insert(&efi.memmap, new_memmap, &fake_mems[i],
+                                 false);

        /* swap into new EFI memmap */
        early_memunmap(new_memmap, efi.memmap.desc_size * new_nr_map);
--- linux-x86.orig/include/linux/efi.h
+++ linux-x86/include/linux/efi.h

@@ -959,8 +959,8 @@ extern int __init efi_memmap_install(phy
 extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
                                         struct range *range);
 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
-                                    void *buf, struct efi_mem_range *mem);
-
+                                    void *buf, struct efi_mem_range *mem,
+                                    bool boot_only);
 extern int efi_config_init(efi_config_table_type_t *arch_tables);
 #ifdef CONFIG_EFI_ESRT
 extern void __init efi_esrt_init(void);

Thanks
Dave