Re: [PATCH] arm64: fix undefined reference to 'printk'

[Ard Biesheuvel]

On 13 March 2018 at 11:41, Arnd Bergmann  wrote:
> The printk symbol was intended as a generic address that is always
> exported, however that turned out to be false with CONFIG_PRINTK=n:
>
> ERROR: "printk" [arch/arm64/kernel/arm64-reloc-test.ko] undefined!
>
> This changes the references to memstart_addr, which should be there
> regardless of configuration.
>
> Fixes: a257e02579e4 ("arm64/kernel: don't ban ADRP to work around Cortex-A53 
> erratum #843419")
> Ard Biesheuvel 

Acked-by: ^^^

> Signed-off-by: Arnd Bergmann 
> ---
>  arch/arm64/kernel/reloc_test_core.c | 2 +-
>  arch/arm64/kernel/reloc_test_syms.S | 4 ++--
>  2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm64/kernel/reloc_test_core.c 
> b/arch/arm64/kernel/reloc_test_core.c
> index a70489c584c7..5915ce5759cc 100644
> --- a/arch/arm64/kernel/reloc_test_core.c
> +++ b/arch/arm64/kernel/reloc_test_core.c
> @@ -45,7 +45,7 @@ static struct {
> { "R_AARCH64_MOVW_SABS_Gn", signed_movw, UL(SYM64_ABS_VAL) },
> { "R_AARCH64_MOVW_UABS_Gn", unsigned_movw, UL(SYM64_ABS_VAL) },
> { "R_AARCH64_ADR_PREL_PG_HI21", relative_adrp, (u64)&sym64_rel },
> -   { "R_AARCH64_ADR_PREL_PG_HI21", relative_adrp_far, (u64)&printk },
> +   { "R_AARCH64_ADR_PREL_PG_HI21", relative_adrp_far, 
> (u64)&memstart_addr },
> { "R_AARCH64_ADR_PREL_LO21",relative_adr, (u64)&sym64_rel },
> { "R_AARCH64_PREL64",   relative_data64, (u64)&sym64_rel },
> { "R_AARCH64_PREL32",   relative_data32, (u64)&sym64_rel },
> diff --git a/arch/arm64/kernel/reloc_test_syms.S 
> b/arch/arm64/kernel/reloc_test_syms.S
> index f333b4b7880d..2b8d9cb8b078 100644
> --- a/arch/arm64/kernel/reloc_test_syms.S
> +++ b/arch/arm64/kernel/reloc_test_syms.S
> @@ -54,8 +54,8 @@ ENDPROC(relative_adrp)
> .align  12
> .space  0xffc
>  ENTRY(relative_adrp_far)
> -   adrpx0, printk
> -   add x0, x0, #:lo12:printk
> +   adrpx0, memstart_addr
> +   add x0, x0, #:lo12:memstart_addr
> ret
>  ENDPROC(relative_adrp_far)
>
> --
> 2.9.0
>

[PATCH] arm64: fix undefined reference to 'printk'

[Arnd Bergmann]

The printk symbol was intended as a generic address that is always
exported, however that turned out to be false with CONFIG_PRINTK=n:

ERROR: "printk" [arch/arm64/kernel/arm64-reloc-test.ko] undefined!

This changes the references to memstart_addr, which should be there
regardless of configuration.

Fixes: a257e02579e4 ("arm64/kernel: don't ban ADRP to work around Cortex-A53 
erratum #843419")
Ard Biesheuvel 
Signed-off-by: Arnd Bergmann 
---
 arch/arm64/kernel/reloc_test_core.c | 2 +-
 arch/arm64/kernel/reloc_test_syms.S | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/kernel/reloc_test_core.c 
b/arch/arm64/kernel/reloc_test_core.c
index a70489c584c7..5915ce5759cc 100644
--- a/arch/arm64/kernel/reloc_test_core.c
+++ b/arch/arm64/kernel/reloc_test_core.c
@@ -45,7 +45,7 @@ static struct {
{ "R_AARCH64_MOVW_SABS_Gn", signed_movw, UL(SYM64_ABS_VAL) },
{ "R_AARCH64_MOVW_UABS_Gn", unsigned_movw, UL(SYM64_ABS_VAL) },
{ "R_AARCH64_ADR_PREL_PG_HI21", relative_adrp, (u64)&sym64_rel },
-   { "R_AARCH64_ADR_PREL_PG_HI21", relative_adrp_far, (u64)&printk },
+   { "R_AARCH64_ADR_PREL_PG_HI21", relative_adrp_far, (u64)&memstart_addr 
},
{ "R_AARCH64_ADR_PREL_LO21",relative_adr, (u64)&sym64_rel },
{ "R_AARCH64_PREL64",   relative_data64, (u64)&sym64_rel },
{ "R_AARCH64_PREL32",   relative_data32, (u64)&sym64_rel },
diff --git a/arch/arm64/kernel/reloc_test_syms.S 
b/arch/arm64/kernel/reloc_test_syms.S
index f333b4b7880d..2b8d9cb8b078 100644
--- a/arch/arm64/kernel/reloc_test_syms.S
+++ b/arch/arm64/kernel/reloc_test_syms.S
@@ -54,8 +54,8 @@ ENDPROC(relative_adrp)
.align  12
.space  0xffc
 ENTRY(relative_adrp_far)
-   adrpx0, printk
-   add x0, x0, #:lo12:printk
+   adrpx0, memstart_addr
+   add x0, x0, #:lo12:memstart_addr
ret
 ENDPROC(relative_adrp_far)
 
-- 
2.9.0