linux-kernel - Re: [patch] x86: optimise page fault entry

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20090121194541.GA22911@cmpxchg.org>
Date:	Wed, 21 Jan 2009 20:45:41 +0100
From:	Johannes Weiner <hannes@...xchg.org>
To:	Nick Piggin <npiggin@...e.de>
Cc:	Ingo Molnar <mingo@...e.hu>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [patch] x86: optimise page fault entry

Nick, here is the patch.  Ingo could you fold that one into Nick's as
a micro-mini minor fix?

On Tue, Jan 20, 2009 at 04:24:26AM +0100, Nick Piggin wrote:

> Index: linux-2.6/arch/x86/mm/fault.c
> ===================================================================
> --- linux-2.6.orig/arch/x86/mm/fault.c
> +++ linux-2.6/arch/x86/mm/fault.c

> @@ -409,15 +409,15 @@ static void show_fault_oops(struct pt_re
>  }
>  
>  #ifdef CONFIG_X86_64
> -static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs,
> -				 unsigned long error_code)
> +static noinline void pgtable_bad(struct pt_regs *regs,
> +			 unsigned long error_code, unsigned long address)
>  {
>  	unsigned long flags = oops_begin();
>  	int sig = SIGKILL;
> -	struct task_struct *tsk;
> +	struct task_struct *tsk = current;
>  
>  	printk(KERN_ALERT "%s: Corrupted page table at address %lx\n",
> -	       current->comm, address);
> +	       tsk->comm, address);
>  	dump_pagetable(address);
>  	tsk = current;

---
tsk is already assigned to current, drop the redundant second
assignment which Nick probably just overlooked when doing the cleanup.

Signed-off-by: Johannes Weiner <hannes@...xchg.org>
---
 arch/x86/mm/fault.c |    1 -
 1 file changed, 1 deletion(-)

--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -419,7 +419,6 @@ static noinline void pgtable_bad(struct 
 	printk(KERN_ALERT "%s: Corrupted page table at address %lx\n",
 	       tsk->comm, address);
 	dump_pagetable(address);
-	tsk = current;
 	tsk->thread.cr2 = address;
 	tsk->thread.trap_no = 14;
 	tsk->thread.error_code = error_code;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/