linux-kernel - [M68KNOMMU]: simplify ColdFire resume code

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>] [day] [month] [year] [list]

Date:	Wed, 25 Jul 2007 22:07:20 +1000
From:	Greg Ungerer <gerg@...pgear.com>
To:	torvalds@...ux-foundation.org
Cc:	gerg@...inux.org, linux-kernel@...r.kernel.org
Subject: [M68KNOMMU]: simplify ColdFire resume code

It is useless to preserve THREAD_SR in `resume'.  The real user's sr
is actually in the stack.  We also don't need to disable interrupts :
we'll never be in an invalid state, the sp switch is atomic.

Signed-off-by: Philippe De Muyter <phdm@...qel.be>
Signed-off-by: Greg Ungerer <gerg@...inux.org>
---


diff -Naur linux-2.6.22/arch/m68knommu/platform/5307/entry.S linux-2.6.22-uc0/arch/m68knommu/platform/5307/entry.S
--- linux-2.6.22/arch/m68knommu/platform/5307/entry.S	2007-07-12 15:23:02.000000000 +1000
+++ linux-2.6.22-uc0/arch/m68knommu/platform/5307/entry.S	2007-07-12 15:27:01.000000000 +1000
@@ -235,16 +216,12 @@
  * Beware - when entering resume, prev (the current task) is
  * in a0, next (the new task) is in a1,so don't change these
  * registers until their contents are no longer needed.
+ * This is always called in supervisor mode, so don't bother to save
+ * and restore sr; user's process sr is actually in the stack.
  */
 ENTRY(resume)
 	movel	%a0, %d1			/* get prev thread in d1 */
 
-	movew	%sr,%d0				/* save thread status reg */
-	movew	%d0,%a0@(TASK_THREAD+THREAD_SR)
-
-	oril	#0x700,%d0			/* disable interrupts */
-	move	%d0,%sr
-
 	movel	sw_usp,%d0			/* save usp */
 	movel	%d0,%a0@(TASK_THREAD+THREAD_USP)
 
@@ -255,7 +232,4 @@
 
 	movel	%a1@(TASK_THREAD+THREAD_USP),%a0 /* restore thread user stack */
 	movel	%a0, sw_usp
-
-	movew	%a1@(TASK_THREAD+THREAD_SR),%d0	/* restore thread status reg */
-	movew	%d0, %sr
 	rts
-
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/