1
0
mirror of https://xff.cz/git/u-boot/ synced 2026-01-25 02:45:21 +01:00
Files
u-boot-megous/include
Ilias Apalodimas 53e54bf50d efi_loader: Avoid emitting efi_var_buf to .GOT
Atish reports that on RISC-V, accessing the EFI variables causes
a kernel panic. An objdump of the file verifies that, since the
global pointer for efi_var_buf ends up in .GOT section which is
not mapped in virtual address space for Linux.

<snip of efi_var_mem_find>

0000000000000084 <efi_var_mem_find>:
  84:   715d                    addi    sp,sp,-80

* objdump -dr
0000000000000086 <.LCFI2>:
  86:   e0a2                    sd  s0,64(sp)
  88:   fc26                    sd  s1,56(sp)
  8a:   e486                    sd  ra,72(sp)
  8c:   f84a                    sd  s2,48(sp)
  8e:   f44e                    sd  s3,40(sp)
  90:   f052                    sd  s4,32(sp)
  92:   ec56                    sd  s5,24(sp)
  94:   00000497            auipc   s1,0x0
            94: R_RISCV_GOT_HI20    efi_var_buf
  98:   0004b483            ld  s1,0(s1) # 94 <.LCFI2+0xe>
            98: R_RISCV_PCREL_LO12_I    .L0
            98: R_RISCV_RELAX   *ABS*

* objdump -t
0000000000000084 g     F .text.efi_runtime  00000000000000b8 efi_var_mem_find

With the patch applied:

* objdump -dr
0000000000000086 <.LCFI2>:
  86:   e0a2                    sd  s0,64(sp)
  88:   fc26                    sd  s1,56(sp)
  8a:   e486                    sd  ra,72(sp)
  8c:   f84a                    sd  s2,48(sp)
  8e:   f44e                    sd  s3,40(sp)
  90:   f052                    sd  s4,32(sp)
  92:   ec56                    sd  s5,24(sp)
  94:   00000497            auipc   s1,0x0
            94: R_RISCV_PCREL_HI20  .LANCHOR0
            94: R_RISCV_RELAX   *ABS*
  98:   00048493            mv  s1,s1
            98: R_RISCV_PCREL_LO12_I    .L0
            98: R_RISCV_RELAX   *ABS*

* objdump -t
0000000000000008 l     O .data.efi_runtime  0000000000000008 efi_var_buf

On arm64 this works, because there's no .GOT entries for this
and everything is converted to relative references.

* objdump -dr (identical pre-post patch, only the new function shows up)
00000000000000b4 <efi_var_mem_find>:
  b4:   aa0003ee    mov x14, x0
  b8:   9000000a    adrp    x10, 0 <efi_var_mem_compare>
            b8: R_AARCH64_ADR_PREL_PG_HI21  .data.efi_runtime
  bc:   91000140    add x0, x10, #0x0
            bc: R_AARCH64_ADD_ABS_LO12_NC   .data.efi_runtime
  c0:   aa0103ed    mov x13, x1
  c4:   79400021    ldrh    w1, [x1]
  c8:   aa0203eb    mov x11, x2
  cc:   f9400400    ldr x0, [x0, #8]
  d0:   b940100c    ldr w12, [x0, #16]
  d4:   8b0c000c    add x12, x0, x12

So let's switch efi_var_buf to static and create a helper function for
anyone that needs to update it.

Fixes: e01aed47d6 ("efi_loader: Enable run-time variable support for tee based variables")
Reported-by: Atish Patra <atishp@atishpatra.org>
Tested-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2021-01-20 08:17:17 +01:00
..
2019-12-06 16:44:20 -05:00
2019-10-16 05:42:27 +02:00
2020-09-30 16:55:03 -04:00
2020-10-22 09:54:53 -04:00
2020-05-11 10:16:49 +05:30
2021-01-15 14:36:12 -05:00
2020-04-17 12:32:36 -04:00
2020-07-09 12:33:24 +08:00
2020-05-18 17:33:33 -04:00
2020-07-28 19:30:39 -06:00
2021-01-12 10:58:04 +05:30
2021-01-12 10:58:04 +05:30
2020-12-26 12:37:28 +01:00
2020-10-30 14:20:27 +01:00
2019-04-23 20:26:43 -06:00
2020-02-05 19:33:46 -07:00
2019-10-13 23:34:43 +02:00
2020-05-07 09:01:42 -04:00
2020-08-03 22:19:54 -04:00
2021-01-13 02:38:01 +01:00
2020-05-18 21:19:23 -04:00
2020-12-31 14:32:27 +01:00
2020-08-07 22:31:32 -04:00
2020-10-30 10:56:11 -04:00
2020-05-18 17:33:33 -04:00
2020-06-12 13:14:07 -04:00
2019-02-20 15:27:09 +08:00
2018-06-13 07:49:12 -04:00
2018-12-06 23:26:32 -05:00
2019-02-09 12:50:22 -07:00
2019-10-14 09:31:41 +02:00
2020-01-20 15:38:16 +01:00
2018-12-05 06:01:35 -07:00
2019-11-07 18:39:16 -05:00
2020-05-18 18:36:55 -04:00
2019-08-11 16:43:41 -04:00
2020-04-17 12:32:36 -04:00
2020-08-04 23:30:02 -04:00
2021-01-16 19:17:11 -05:00
2019-12-02 18:23:11 -05:00
2020-10-27 08:13:33 +01:00
2020-01-25 12:04:36 -05:00
2020-12-13 07:58:17 -07:00
2018-10-09 04:40:27 -06:00
2021-01-16 14:48:23 -05:00
2020-07-17 10:47:19 -04:00
2020-12-18 20:32:21 -07:00
2020-06-14 21:07:20 +02:00
2020-02-05 19:33:46 -07:00
2020-06-14 21:07:20 +02:00
2020-07-09 06:02:44 +02:00
2020-09-30 11:55:23 -04:00
2018-07-19 16:31:37 -04:00
2020-02-05 19:33:46 -07:00
2020-08-03 22:19:54 -04:00
2021-01-05 16:20:26 -05:00
2019-02-01 16:59:12 +01:00
2021-01-05 12:24:40 -07:00
2019-05-21 17:33:23 -06:00
2020-08-23 13:43:10 -04:00
2020-10-22 09:54:53 -04:00
2018-10-09 04:40:27 -06:00
2020-11-06 10:18:20 +08:00
2020-08-03 22:19:54 -04:00
2020-01-21 15:56:15 +01:00
2018-09-28 18:26:32 +02:00
2020-08-03 22:19:54 -04:00
2020-08-03 22:19:54 -04:00
2021-01-15 14:36:12 -05:00