rpms/kernel/F-12 sparc-align-clone-and-signal-stacks-to-16-bytes.patch, NONE, 1.1.2.1

[Dennis Gilmore]

Author: ausil

Update of /cvs/extras/rpms/kernel/F-12
In directory cvs1.fedora.phx.redhat.com:/tmp/cvs-serv14074

Added Files:
      Tag: private-fedora-12-2_6_31
	sparc-align-clone-and-signal-stacks-to-16-bytes.patch 
Log Message:
add sparc stack alignment patch


sparc-align-clone-and-signal-stacks-to-16-bytes.patch:
 process_32.c |    2 +-
 process_64.c |    8 ++++----
 signal32.c   |   10 ++++++----
 signal_32.c  |    6 ++++--
 signal_64.c  |   10 +++++-----
 5 files changed, 20 insertions(+), 16 deletions(-)

--- NEW FILE sparc-align-clone-and-signal-stacks-to-16-bytes.patch ---
>From davem at davemloft.net Tue Feb  9 18:50:06 2010
Return-Path: <sparclinux-owner at vger.kernel.org>
X-Original-To: dennis at ausil.us
Delivered-To: dennis at ausil.us
Received: from localhost (unknown [127.0.0.1])
	by mail.ausil.us (Postfix) with ESMTP id 78F2B64810E
	for <dennis at ausil.us>; Wed, 10 Feb 2010 00:49:56 +0000 (UTC)
X-Virus-Scanned: amavisd-new at example.com
Received: from mail.ausil.us ([127.0.0.1])
	by localhost (mail.ausil.us [127.0.0.1]) (amavisd-new, port 10024)
	with ESMTP id UIRD2FEV0SCn for <dennis at ausil.us>;
	Wed, 10 Feb 2010 00:49:52 +0000 (UTC)
X-Greylist: from auto-whitelisted by SQLgrey-1.7.5
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by mail.ausil.us (Postfix) with ESMTP id 45AAE64810F
	for <dennis at ausil.us>; Wed, 10 Feb 2010 00:49:52 +0000 (UTC)
Received: (majordomo at vger.kernel.org) by vger.kernel.org via listexpand
	id S1753974Ab0BJAtw (ORCPT <rfc822;dennis at ausil.us>);
	Tue, 9 Feb 2010 19:49:52 -0500
Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:41154
	"EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK)
	by vger.kernel.org with ESMTP id S1752970Ab0BJAtv (ORCPT
	<rfc822;sparclinux at vger.kernel.org>); Tue, 9 Feb 2010 19:49:51 -0500
Received: from localhost (localhost [127.0.0.1])
	by sunset.davemloft.net (Postfix) with ESMTP id 3DD4924C10E;
	Tue,  9 Feb 2010 16:50:06 -0800 (PST)
Date:	Tue, 09 Feb 2010 16:50:06 -0800 (PST)
Message-Id: <20100209.165006.142022647.davem at davemloft.net>
To: sparclinux at vger.kernel.org
CC: tcallawa at redhat.com,
 joy at debian.org
Subject: [PATCH] sparc: Align clone and signal stacks to 16 bytes.
From:	David Miller <davem at davemloft.net>
X-Mailer: Mew version 6.3 on Emacs 23.1 / Mule 6.0 (HANACHIRUSATO)
Mime-Version: 1.0
Content-Type: Text/Plain;
  charset=us-ascii
Content-Transfer-Encoding: 7bit
Sender:	sparclinux-owner at vger.kernel.org
Precedence: bulk
List-ID: <sparclinux.vger.kernel.org>
X-Mailing-List:	sparclinux at vger.kernel.org
X-UID: 6098
X-Length: 8091
Status: R
X-Status: N
X-KMail-EncryptionState:  
X-KMail-SignatureState:  
X-KMail-MDN-Sent:  


[ Josip, when I hit this I thought that if it were a gcc bug it might
  explain your gcc-4.4 kernel failures.  That's why I haven't played
  with your machines yet.  Now that I know this is actually a kernel
  bug effecting only user applications, I will go pursue your
  issues. ]

I originally thought this was a gcc bug:

	http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43004

But it's actually a kernel issue.

When we clone or create a signal stack we only 8-byte align the stack
frame, it should be 16-byte aligned on 64-bit.  Use 16-byte alignment
for 32-bit too since that's harmless and it's cheaper that way.

Distribution folks you really want this in your kernels, otherwise
64-bit threads and signal handlers will have broken alloca() and
corrupt their stacks.

I'll push this to Linus and -stable.

--------------------
sparc: Align clone and signal stacks to 16 bytes.

This is mandatory for 64-bit processes, and doing it also for 32-bit
processes saves a conditional in the compat case.

This fixes the glibc/nptl/tst-stdio1 test case, as well
as many others, on 64-bit.

Signed-off-by: David S. Miller <davem at davemloft.net>
---
 arch/sparc/kernel/process_32.c |    2 +-
 arch/sparc/kernel/process_64.c |    8 ++++----
 arch/sparc/kernel/signal32.c   |   10 ++++++----
 arch/sparc/kernel/signal_32.c  |    6 ++++--
 arch/sparc/kernel/signal_64.c  |    8 +++++---
 5 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c
index 2830b41..f23c8fd 100644
--- a/arch/sparc/kernel/process_32.c
+++ b/arch/sparc/kernel/process_32.c
@@ -526,7 +526,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 			 * Set some valid stack frames to give to the child.
 			 */
 			childstack = (struct sparc_stackf __user *)
-				(sp & ~0x7UL);
+				(sp & ~0x15UL);
 			parentstack = (struct sparc_stackf __user *)
 				regs->u_regs[UREG_FP];
 
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index 18d6785..6679eeb 100644
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -406,11 +406,11 @@ static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 	} else
 		__get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
 
-	/* Now 8-byte align the stack as this is mandatory in the
-	 * Sparc ABI due to how register windows work.  This hides
-	 * the restriction from thread libraries etc.  -DaveM
+	/* Now align the stack as this is mandatory in the Sparc ABI
+	 * due to how register windows work.  This hides the
+	 * restriction from thread libraries etc.
 	 */
-	csp &= ~7UL;
+	csp &= ~15UL;
 
 	distance = fp - psp;
 	rval = (csp - distance);
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index ba5b09a..ea22cd3 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c
@@ -120,8 +120,8 @@ struct rt_signal_frame32 {
 };
 
 /* Align macros */
-#define SF_ALIGNEDSZ  (((sizeof(struct signal_frame32) + 7) & (~7)))
-#define RT_ALIGNEDSZ  (((sizeof(struct rt_signal_frame32) + 7) & (~7)))
+#define SF_ALIGNEDSZ  (((sizeof(struct signal_frame32) + 15) & (~15)))
+#define RT_ALIGNEDSZ  (((sizeof(struct rt_signal_frame32) + 15) & (~15)))
 
 int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
 {
@@ -420,15 +420,17 @@ static void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, uns
 			sp = current->sas_ss_sp + current->sas_ss_size;
 	}
 
+	sp -= framesize;
+
 	/* Always align the stack frame.  This handles two cases.  First,
 	 * sigaltstack need not be mindful of platform specific stack
 	 * alignment.  Second, if we took this signal because the stack
 	 * is not aligned properly, we'd like to take the signal cleanly
 	 * and report that.
 	 */
-	sp &= ~7UL;
+	sp &= ~15UL;
 
-	return (void __user *)(sp - framesize);
+	return (void __user *) sp;
 }
 
 static int save_fpu_state32(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 7ce1a10..9882df9 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -267,15 +267,17 @@ static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *re
 			sp = current->sas_ss_sp + current->sas_ss_size;
 	}
 
+	sp -= framesize;
+
 	/* Always align the stack frame.  This handles two cases.  First,
 	 * sigaltstack need not be mindful of platform specific stack
 	 * alignment.  Second, if we took this signal because the stack
 	 * is not aligned properly, we'd like to take the signal cleanly
 	 * and report that.
 	 */
-	sp &= ~7UL;
+	sp &= ~15UL;
 
-	return (void __user *)(sp - framesize);
+	return (void __user *) sp;
 }
 
 static inline int
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
index 647afbd..9fa48c3 100644
--- a/arch/sparc/kernel/signal_64.c
+++ b/arch/sparc/kernel/signal_64.c
@@ -353,7 +353,7 @@ segv:
 /* Checks if the fp is valid */
 static int invalid_frame_pointer(void __user *fp, int fplen)
 {
-	if (((unsigned long) fp) & 7)
+	if (((unsigned long) fp) & 15)
 		return 1;
 	return 0;
 }
@@ -396,15 +396,17 @@ static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *
 			sp = current->sas_ss_sp + current->sas_ss_size;
 	}
 
+	sp -= framesize;
+
 	/* Always align the stack frame.  This handles two cases.  First,
 	 * sigaltstack need not be mindful of platform specific stack
 	 * alignment.  Second, if we took this signal because the stack
 	 * is not aligned properly, we'd like to take the signal cleanly
 	 * and report that.
 	 */
-	sp &= ~7UL;
+	sp &= ~15UL;
 
-	return (void __user *)(sp - framesize);
+	return (void __user *) sp;
 }
 
 static inline void
-- 
1.6.6.1

--
To unsubscribe from this list: send the line "unsubscribe sparclinux" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html