Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

"* Fix EFI boot regression introduced during the merge window where the
   firmware was reading random values from the stack because we were
   passing a pointer to the wrong object type.

 * Kernel corruption has been reported when booting with the EFI boot
   stub which was tracked down to setting a bogus value for
   bp->hdr.code32_start, resulting in corruption during relocation.

 * Olivier Martin reported that the wrong file handles were being passed
   to efi_file_(read|close), which works for x86 by luck due to the way
   that the FAT driver is implemented, but doesn't work on ARM."

Signed-off-by: Ingo Molnar <mingo@kernel.org>

3 files changed, 15 insertions, 21 deletions

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 1e6146137f8e..4703a6c4b8e3 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -112,7 +112,7 @@ __file_size64(void *__fh, efi_char16_t *filename_16,
         efi_file_info_t *info;
         efi_status_t status;
         efi_guid_t info_guid = EFI_FILE_INFO_ID;
-        u32 info_sz;
+        u64 info_sz;
 
         status = efi_early->call((unsigned long)fh->open, fh, &h, filename_16,
                                  EFI_FILE_MODE_READ, (u64)0);
@@ -167,31 +167,31 @@ efi_file_size(efi_system_table_t *sys_table, void *__fh,
 }
 
 static inline efi_status_t
-efi_file_read(void *__fh, void *handle, unsigned long *size, void *addr)
+efi_file_read(void *handle, unsigned long *size, void *addr)
 {
         unsigned long func;
 
         if (efi_early->is64) {
-                efi_file_handle_64_t *fh = __fh;
+                efi_file_handle_64_t *fh = handle;
 
                 func = (unsigned long)fh->read;
                 return efi_early->call(func, handle, size, addr);
         } else {
-                efi_file_handle_32_t *fh = __fh;
+                efi_file_handle_32_t *fh = handle;
 
                 func = (unsigned long)fh->read;
                 return efi_early->call(func, handle, size, addr);
         }
 }
 
-static inline efi_status_t efi_file_close(void *__fh, void *handle)
+static inline efi_status_t efi_file_close(void *handle)
 {
         if (efi_early->is64) {
-                efi_file_handle_64_t *fh = __fh;
+                efi_file_handle_64_t *fh = handle;
 
                 return efi_early->call((unsigned long)fh->close, handle);
         } else {
-                efi_file_handle_32_t *fh = __fh;
+                efi_file_handle_32_t *fh = handle;
 
                 return efi_early->call((unsigned long)fh->close, handle);
         }
@@ -1016,6 +1016,9 @@ void setup_graphics(struct boot_params *boot_params)
  * Because the x86 boot code expects to be passed a boot_params we
  * need to create one ourselves (usually the bootloader would create
  * one for us).
+ *
+ * The caller is responsible for filling out ->code32_start in the
+ * returned boot_params.
  */
 struct boot_params *make_boot_params(struct efi_config *c)
 {
@@ -1081,8 +1084,6 @@ struct boot_params *make_boot_params(struct efi_config *c)
         hdr->vid_mode = 0xffff;
         hdr->boot_flag = 0xAA55;
 
-        hdr->code32_start = (__u64)(unsigned long)image->image_base;
-
         hdr->type_of_loader = 0x21;
 
         /* Convert unicode cmdline to ascii */
diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index de9d4200d305..cbed1407a5cd 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -59,6 +59,7 @@ ENTRY(efi_pe_entry)
         call    make_boot_params
         cmpl    $0, %eax
         je      fail
+        movl    %esi, BP_code32_start(%eax)
         popl    %ecx
         pushl   %eax
         pushl   %ecx
@@ -90,12 +91,7 @@ fail:
         hlt
         jmp     fail
 2:
-        call    3f
-3:
-        popl    %eax
-        subl    $3b, %eax
-        subl    BP_pref_address(%esi), %eax
-        add     BP_code32_start(%esi), %eax
+        movl    BP_code32_start(%esi), %eax
         leal    preferred_addr(%eax), %eax
         jmp     *%eax
 
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 57e58a5fa210..0d558ee899ae 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -261,6 +261,8 @@ ENTRY(efi_pe_entry)
         cmpq    $0,%rax
         je      fail
         mov     %rax, %rsi
+        leaq    startup_32(%rip), %rax
+        movl    %eax, BP_code32_start(%rsi)
         jmp     2f              /* Skip the relocation */
 
 handover_entry:
@@ -284,12 +286,7 @@ fail:
         hlt
         jmp     fail
 2:
-        call    3f
-3:
-        popq    %rax
-        subq    $3b, %rax
-        subq    BP_pref_address(%rsi), %rax
-        add     BP_code32_start(%esi), %eax
+        movl    BP_code32_start(%esi), %eax
         leaq    preferred_addr(%rax), %rax
         jmp     *%rax