# Re: \[PATCH v7 1/6\] x86/vdso: Fix DWARF generation for getrandom()

- From: H. Peter Anvin \<hpa@zytor.com\>
- Date: 2026-02-04 00:45:27 
- List: linux-trace-kernel
- Page: https://ratatoskr.run/linux-trace-kernel/2026/02/3400515
- Thread: https://ratatoskr.run/linux-trace-kernel/2026/02/3399878/t.md

```text
On 2026-02-03 09:19, Jens Remus wrote:
> From: Josh Poimboeuf <jpoimboe@kernel.org>
> 
> Add CFI annotations to the VDSO implementation of getrandom() so it will
> have valid DWARF unwinding metadata.
> 
> Fixes: 33385150ac45 ("x86: vdso: Wire up getrandom() vDSO implementation")
> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
> Signed-off-by: Jens Remus <redacted>
> ---
>  arch/x86/entry/vdso/vdso64/vgetrandom-chacha.S | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/entry/vdso/vdso64/vgetrandom-chacha.S b/arch/x86/entry/vdso/vdso64/vgetrandom-chacha.S
> index bcba5639b8ee..cc82da9216fb 100644
> --- a/arch/x86/entry/vdso/vdso64/vgetrandom-chacha.S
> +++ b/arch/x86/entry/vdso/vdso64/vgetrandom-chacha.S
> @@ -4,7 +4,7 @@
>   */
>  
>  #include <linux/linkage.h>
> -#include <asm/frame.h>
> +#include <asm/dwarf2.h>
>  
>  .section	.rodata, "a"
>  .align 16
> @@ -22,7 +22,7 @@ CONSTANTS:	.octa 0x6b20657479622d323320646e61707865
>   *	rcx: number of 64-byte blocks to write to output
>   */
>  SYM_FUNC_START(__arch_chacha20_blocks_nostack)
> -
> +	CFI_STARTPROC
>  .set	output,		%rdi
>  .set	key,		%rsi
>  .set	counter,	%rdx
> @@ -175,4 +175,5 @@ SYM_FUNC_START(__arch_chacha20_blocks_nostack)
>  	pxor		temp,temp
>  
>  	ret
> +	CFI_ENDPROC
>  SYM_FUNC_END(__arch_chacha20_blocks_nostack)

Looks good to me.

Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com>

```