Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1673238 > unrolled thread

[PATCH] KVM: x86: remove ignored type attribute

Started byNick Desaulniers <nick.desaulniers@gmail.com>
First post2017-06-23 06:50 +0200
Last post2017-06-30 12:50 +0200
Articles 5 — 2 participants

Back to article view | Back to linux.kernel

Contents

  [PATCH] KVM: x86: remove ignored type attribute Nick Desaulniers <nick.desaulniers@gmail.com> - 2017-06-23 06:50 +0200
    Re: [PATCH] KVM: x86: remove ignored type attribute Paolo Bonzini <pbonzini@redhat.com> - 2017-06-27 16:40 +0200
    [PATCH v2] KVM: x86: remove ignored type attribute Nick Desaulniers <nick.desaulniers@gmail.com> - 2017-06-28 04:40 +0200
      Re: [PATCH v2] KVM: x86: remove ignored type attribute Nick Desaulniers <nick.desaulniers@gmail.com> - 2017-06-28 04:50 +0200
      Re: [PATCH v2] KVM: x86: remove ignored type attribute Paolo Bonzini <pbonzini@redhat.com> - 2017-06-30 12:50 +0200

#1673238 — [PATCH] KVM: x86: remove ignored type attribute

FromNick Desaulniers <nick.desaulniers@gmail.com>
Date2017-06-23 06:50 +0200
Subject[PATCH] KVM: x86: remove ignored type attribute
Message-ID<tVoHD-5Z8-3@gated-at.bofh.it>
The macro insn_fetch marks the 'type' argument as having a specified
alignment.  Type attributes can only be applied to structs, unions, or
enums, but insn_fetch is only ever invoked with integral types, so Clang
produces 19 -Wignored-attributes warnings for this source file.

Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
---
 arch/x86/kvm/emulate.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 7611c034bf95..409081977e59 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -900,7 +900,7 @@ static __always_inline int do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt,
 	if (rc != X86EMUL_CONTINUE)					\
 		goto done;						\
 	ctxt->_eip += sizeof(_type);					\
-	_x = *(_type __aligned(1) *) ctxt->fetch.ptr;			\
+	_x = *(_type *) ctxt->fetch.ptr;			\
 	ctxt->fetch.ptr += sizeof(_type);				\
 	_x;								\
 })
-- 
2.11.0

[toc] | [next] | [standalone]

#1675816

FromPaolo Bonzini <pbonzini@redhat.com>
Date2017-06-27 16:40 +0200
Message-ID<tWZOO-1NK-13@gated-at.bofh.it>
In reply to#1673238

On 23/06/2017 06:41, Nick Desaulniers wrote:
> The macro insn_fetch marks the 'type' argument as having a specified
> alignment.  Type attributes can only be applied to structs, unions, or
> enums, but insn_fetch is only ever invoked with integral types, so Clang
> produces 19 -Wignored-attributes warnings for this source file.
> 
> Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
> ---
>  arch/x86/kvm/emulate.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
> index 7611c034bf95..409081977e59 100644
> --- a/arch/x86/kvm/emulate.c
> +++ b/arch/x86/kvm/emulate.c
> @@ -900,7 +900,7 @@ static __always_inline int do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt,
>  	if (rc != X86EMUL_CONTINUE)					\
>  		goto done;						\
>  	ctxt->_eip += sizeof(_type);					\
> -	_x = *(_type __aligned(1) *) ctxt->fetch.ptr;			\
> +	_x = *(_type *) ctxt->fetch.ptr;			\
>  	ctxt->fetch.ptr += sizeof(_type);				\
>  	_x;								\
>  })
> 

Can you make a patch that uses memcpy instead?  Both GCC and clang will
compile it to a simple load.

Paolo

[toc] | [prev] | [next] | [standalone]

#1676325 — [PATCH v2] KVM: x86: remove ignored type attribute

FromNick Desaulniers <nick.desaulniers@gmail.com>
Date2017-06-28 04:40 +0200
Subject[PATCH v2] KVM: x86: remove ignored type attribute
Message-ID<tXb3A-V7-7@gated-at.bofh.it>
In reply to#1673238
The macro insn_fetch marks the 'type' argument as having a specified
alignment.  Type attributes can only be applied to structs, unions, or
enums, but insn_fetch is only ever invoked with integral types, so Clang
produces 19 -Wignored-attributes warnings for this source file.

Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
---
Changes in v2:
* prefer memcpy
* fix up trailing tabs

 arch/x86/kvm/emulate.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 7611c034bf95..f9c0359f3fdd 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -900,7 +900,7 @@ static __always_inline int do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt,
 	if (rc != X86EMUL_CONTINUE)					\
 		goto done;						\
 	ctxt->_eip += sizeof(_type);					\
-	_x = *(_type __aligned(1) *) ctxt->fetch.ptr;			\
+	memcpy(&_x, ctxt->fetch.ptr, sizeof(_type));		\
 	ctxt->fetch.ptr += sizeof(_type);				\
 	_x;								\
 })
-- 
2.11.0

[toc] | [prev] | [next] | [standalone]

#1676328 — Re: [PATCH v2] KVM: x86: remove ignored type attribute

FromNick Desaulniers <nick.desaulniers@gmail.com>
Date2017-06-28 04:50 +0200
SubjectRe: [PATCH v2] KVM: x86: remove ignored type attribute
Message-ID<tXbdg-Yp-7@gated-at.bofh.it>
In reply to#1676325
gah, forgot to amend the trailing tab change in.

Do you mind just fixing it up when you merge or shall I send v3?

[toc] | [prev] | [next] | [standalone]

#1678688 — Re: [PATCH v2] KVM: x86: remove ignored type attribute

FromPaolo Bonzini <pbonzini@redhat.com>
Date2017-06-30 12:50 +0200
SubjectRe: [PATCH v2] KVM: x86: remove ignored type attribute
Message-ID<tY1ER-4os-1@gated-at.bofh.it>
In reply to#1676325

On 28/06/2017 04:37, Nick Desaulniers wrote:
> The macro insn_fetch marks the 'type' argument as having a specified
> alignment.  Type attributes can only be applied to structs, unions, or
> enums, but insn_fetch is only ever invoked with integral types, so Clang
> produces 19 -Wignored-attributes warnings for this source file.
> 
> Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
> ---
> Changes in v2:
> * prefer memcpy
> * fix up trailing tabs
> 
>  arch/x86/kvm/emulate.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
> index 7611c034bf95..f9c0359f3fdd 100644
> --- a/arch/x86/kvm/emulate.c
> +++ b/arch/x86/kvm/emulate.c
> @@ -900,7 +900,7 @@ static __always_inline int do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt,
>  	if (rc != X86EMUL_CONTINUE)					\
>  		goto done;						\
>  	ctxt->_eip += sizeof(_type);					\
> -	_x = *(_type __aligned(1) *) ctxt->fetch.ptr;			\
> +	memcpy(&_x, ctxt->fetch.ptr, sizeof(_type));		\
>  	ctxt->fetch.ptr += sizeof(_type);				\
>  	_x;								\
>  })
> 

Fixed up the tab and pushed, thanks.

Paolo

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web