Re: [PATCH v2 06/12] x86/retpoline/crypto: Convert xen assembler indirect jumps

From: Juergen Gross
Date: Thu Jan 04 2018 - 01:48:40 EST


On 04/01/18 03:00, Andi Kleen wrote:
> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>
> Convert all indirect jumps in xen inline assembler code to use
> non speculative sequences.
>
> Based on code from David Woodhouse and Tim Chen
>
> Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> ---
> arch/x86/crypto/camellia-aesni-avx2-asm_64.S | 1 +
> arch/x86/include/asm/xen/hypercall.h | 3 ++-
> 2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/crypto/camellia-aesni-avx2-asm_64.S b/arch/x86/crypto/camellia-aesni-avx2-asm_64.S
> index 1743e6850e00..9cd8450a2050 100644
> --- a/arch/x86/crypto/camellia-aesni-avx2-asm_64.S
> +++ b/arch/x86/crypto/camellia-aesni-avx2-asm_64.S
> @@ -12,6 +12,7 @@
>
> #include <linux/linkage.h>
> #include <asm/frame.h>
> +#include <asm/jump-asm.h>

I fail to connect this change to the patch title.

Maybe should be part of the crypto patch?

>
> #define CAMELLIA_TABLE_BYTE_LEN 272
>
> diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
> index 7cb282e9e587..91de35bcce5e 100644
> --- a/arch/x86/include/asm/xen/hypercall.h
> +++ b/arch/x86/include/asm/xen/hypercall.h
> @@ -44,6 +44,7 @@
> #include <asm/page.h>
> #include <asm/pgtable.h>
> #include <asm/smap.h>
> +#include <asm/jump-asm.h>
>
> #include <xen/interface/xen.h>
> #include <xen/interface/sched.h>
> @@ -217,7 +218,7 @@ privcmd_call(unsigned call,
> __HYPERCALL_5ARG(a1, a2, a3, a4, a5);
>
> stac();
> - asm volatile("call *%[call]"
> + asm volatile(NOSPEC_CALL("%[call]")
> : __HYPERCALL_5PARAM
> : [call] "a" (&hypercall_page[call])
> : __HYPERCALL_CLOBBER5);
>

Acked-by: Juergen Gross <jgross@xxxxxxxx>


Juergen