[PATCH] x86/iperm: remove unused pointers

[PATCH] x86/iperm: remove unused pointers

[Alex Shi]

No one use the prev/next pointers in its function after commit 22fe5b0439dd
("x86/ioperm: Move TSS bitmap update to exit to user work"). So better to
remove them.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Thomas Gleixner <tglx@linutronix.de> 
Cc: Ingo Molnar <mingo@redhat.com> 
Cc: Borislav Petkov <bp@alien8.de> 
Cc: "H. Peter Anvin" <hpa@zytor.com> 
Cc: x86@kernel.org 
Cc: Andy Lutomirski <luto@kernel.org> 
Cc: Rik van Riel <riel@surriel.com> 
Cc: Dave Hansen <dave.hansen@intel.com> 
Cc: Waiman Long <longman@redhat.com> 
Cc: Marcelo Tosatti <mtosatti@redhat.com> 
Cc: linux-kernel@vger.kernel.org 
---
 arch/x86/kernel/process.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 61e93a318983..839b5244e3b7 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -615,12 +615,8 @@ void speculation_ctrl_update_current(void)
 
 void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p)
 {
-	struct thread_struct *prev, *next;
 	unsigned long tifp, tifn;
 
-	prev = &prev_p->thread;
-	next = &next_p->thread;
-
 	tifn = READ_ONCE(task_thread_info(next_p)->flags);
 	tifp = READ_ONCE(task_thread_info(prev_p)->flags);
 
-- 
1.8.3.1

Re: [PATCH] x86/iperm: remove unused pointers

[Waiman Long]

On 1/21/20 3:40 AM, Alex Shi wrote:
> No one use the prev/next pointers in its function after commit 22fe5b0439dd
> ("x86/ioperm: Move TSS bitmap update to exit to user work"). So better to
> remove them.
>
> Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
> Cc: Thomas Gleixner <tglx@linutronix.de> 
> Cc: Ingo Molnar <mingo@redhat.com> 
> Cc: Borislav Petkov <bp@alien8.de> 
> Cc: "H. Peter Anvin" <hpa@zytor.com> 
> Cc: x86@kernel.org 
> Cc: Andy Lutomirski <luto@kernel.org> 
> Cc: Rik van Riel <riel@surriel.com> 
> Cc: Dave Hansen <dave.hansen@intel.com> 
> Cc: Waiman Long <longman@redhat.com> 
> Cc: Marcelo Tosatti <mtosatti@redhat.com> 
> Cc: linux-kernel@vger.kernel.org 
> ---
>  arch/x86/kernel/process.c | 4 ----
>  1 file changed, 4 deletions(-)
>
> diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
> index 61e93a318983..839b5244e3b7 100644
> --- a/arch/x86/kernel/process.c
> +++ b/arch/x86/kernel/process.c
> @@ -615,12 +615,8 @@ void speculation_ctrl_update_current(void)
>  
>  void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p)
>  {
> -	struct thread_struct *prev, *next;
>  	unsigned long tifp, tifn;
>  
> -	prev = &prev_p->thread;
> -	next = &next_p->thread;
> -
>  	tifn = READ_ONCE(task_thread_info(next_p)->flags);
>  	tifp = READ_ONCE(task_thread_info(prev_p)->flags);
>  

Acked-by: Waiman Long <longman@redhat.com>

Re: [PATCH] x86/iperm: remove unused pointers

[Borislav Petkov]

On Tue, Jan 21, 2020 at 04:40:54PM +0800, Alex Shi wrote:
> No one use the prev/next pointers in its function after commit 22fe5b0439dd
> ("x86/ioperm: Move TSS bitmap update to exit to user work"). So better to
> remove them.
> 
> Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
> Cc: Thomas Gleixner <tglx@linutronix.de> 
> Cc: Ingo Molnar <mingo@redhat.com> 
> Cc: Borislav Petkov <bp@alien8.de> 
> Cc: "H. Peter Anvin" <hpa@zytor.com> 
> Cc: x86@kernel.org 
> Cc: Andy Lutomirski <luto@kernel.org> 
> Cc: Rik van Riel <riel@surriel.com> 
> Cc: Dave Hansen <dave.hansen@intel.com> 
> Cc: Waiman Long <longman@redhat.com> 
> Cc: Marcelo Tosatti <mtosatti@redhat.com> 
> Cc: linux-kernel@vger.kernel.org 
> ---
>  arch/x86/kernel/process.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
> index 61e93a318983..839b5244e3b7 100644
> --- a/arch/x86/kernel/process.c
> +++ b/arch/x86/kernel/process.c
> @@ -615,12 +615,8 @@ void speculation_ctrl_update_current(void)
>  
>  void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p)
>  {
> -	struct thread_struct *prev, *next;
>  	unsigned long tifp, tifn;
>  
> -	prev = &prev_p->thread;
> -	next = &next_p->thread;
> -
>  	tifn = READ_ONCE(task_thread_info(next_p)->flags);
>  	tifp = READ_ONCE(task_thread_info(prev_p)->flags);
>  
> -- 

https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=x86/cleanups&id=27353d5785bca61bb49cfd7c78e14f1d21e66ec5

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette