Automatic merge of...

Automatic merge of rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git branch HEAD

arch/i386/Kconfig

@@ -1163,7 +1163,7 @@ config PCI_DIRECT
 
 config PCI_MMCONFIG
 	bool
-	depends on PCI && (PCI_GOMMCONFIG || (PCI_GOANY && ACPI))
+	depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
 	select ACPI_BOOT
 	default y
 

arch/i386/pci/irq.c

@@ -1029,7 +1029,6 @@ void pcibios_penalize_isa_irq(int irq)
 static int pirq_enable_irq(struct pci_dev *dev)
 {
 	u8 pin;
-	extern int via_interrupt_line_quirk;
 	struct pci_dev *temp_dev;
 
 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
@@ -1084,10 +1083,6 @@ static int pirq_enable_irq(struct pci_dev *dev)
 		printk(KERN_WARNING "PCI: No IRQ known for interrupt pin %c of device %s.%s\n",
 		       'A' + pin, pci_name(dev), msg);
 	}
-	/* VIA bridges use interrupt line for apic/pci steering across
-	   the V-Link */
-	else if (via_interrupt_line_quirk)
-		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq & 15);
 	return 0;
 }
 

arch/x86_64/Kconfig

@@ -421,7 +421,7 @@ config PCI_DIRECT
 
 config PCI_MMCONFIG
 	bool "Support mmconfig PCI config space access"
-	depends on PCI
+	depends on PCI && ACPI
 	select ACPI_BOOT
 
 config UNORDERED_IO

drivers/acpi/Kconfig

@@ -40,13 +40,12 @@ config ACPI
 	  available at:
 	  <http://www.acpi.info>
 
+if ACPI
+
 config ACPI_BOOT
 	bool
-	depends on ACPI || X86_HT
 	default y
 
-if ACPI
-
 config ACPI_INTERPRETER
 	bool
 	depends on !IA64_SGI_SN

drivers/acpi/pci_irq.c

@@ -391,7 +391,6 @@ acpi_pci_irq_enable (
 	u8			pin = 0;
 	int			edge_level = ACPI_LEVEL_SENSITIVE;
 	int			active_high_low = ACPI_ACTIVE_LOW;
-	extern int		via_interrupt_line_quirk;
 	char			*link = NULL;
 
 	ACPI_FUNCTION_TRACE("acpi_pci_irq_enable");
@@ -444,9 +443,6 @@ acpi_pci_irq_enable (
 		}
  	}
 
-	if (via_interrupt_line_quirk)
-		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq & 15);
-
 	dev->irq = acpi_register_gsi(irq, edge_level, active_high_low);
 
 	printk(KERN_INFO PREFIX "PCI Interrupt %s[%c] -> ",

drivers/ide/ide-cd.c

@@ -1932,8 +1932,11 @@ static ide_startstop_t cdrom_do_block_pc(ide_drive_t *drive, struct request *rq)
 
 		/*
 		 * check if dma is safe
+		 *
+		 * NOTE! The "len" and "addr" checks should possibly have
+		 * separate masks.
 		 */
-		if ((rq->data_len & 3) || (addr & mask))
+		if ((rq->data_len & mask) || (addr & mask))
 			info->dma = 0;
 	}
 

drivers/pci/quirks.c

@@ -18,6 +18,7 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/delay.h>
+#include <linux/acpi.h>
 #include "pci.h"
 
 /* Deal with broken BIOS'es that neglect to enable passive release,
@@ -467,9 +468,6 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8131_APIC,
  * non-x86 architectures (yes Via exists on PPC among other places),
  * we must mask the PCI_INTERRUPT_LINE value versus 0xf to get
  * interrupts delivered properly.
- *
- * TODO: When we have device-specific interrupt routers,
- * quirk_via_irqpic will go away from quirks.
  */
 
 /*
@@ -494,6 +492,29 @@ static void __devinit quirk_via_acpi(struct pci_dev *d)
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA,	PCI_DEVICE_ID_VIA_82C586_3,	quirk_via_acpi );
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA,	PCI_DEVICE_ID_VIA_82C686_4,	quirk_via_acpi );
 
+static void quirk_via_irqpic(struct pci_dev *dev)
+{
+	u8 irq, new_irq;
+
+#ifdef CONFIG_X86_IO_APIC
+	if (nr_ioapics && !skip_ioapic_setup)
+		return;
+#endif
+#ifdef CONFIG_ACPI
+	if (acpi_irq_model != ACPI_IRQ_MODEL_PIC)
+		return;
+#endif
+	new_irq = dev->irq & 0xf;
+	pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
+	if (new_irq != irq) {
+		printk(KERN_INFO "PCI: Via PIC IRQ fixup for %s, from %d to %d\n",
+			pci_name(dev), irq, new_irq);
+		udelay(15);	/* unknown if delay really needed */
+		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, new_irq);
+	}
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_VIA, PCI_ANY_ID, quirk_via_irqpic);
+
 /*
  * PIIX3 USB: We have to disable USB interrupts that are
  * hardwired to PIRQD# and may be shared with an
@@ -683,19 +704,6 @@ static void __init quirk_disable_pxb(struct pci_dev *pdev)
 }
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_82454NX,	quirk_disable_pxb );
 
-/*
- *	VIA northbridges care about PCI_INTERRUPT_LINE
- */
-int via_interrupt_line_quirk;
-
-static void __devinit quirk_via_bridge(struct pci_dev *pdev)
-{
-	if(pdev->devfn == 0) {
-		printk(KERN_INFO "PCI: Via IRQ fixup\n");
-		via_interrupt_line_quirk = 1;
-	}
-}
-DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA,	PCI_ANY_ID,                     quirk_via_bridge );
 
 /*
  *	Serverworks CSB5 IDE does not fully support native mode

drivers/usb/media/pwc/Makefile

 ifneq ($(KERNELRELEASE),)
 
-pwc-objs	:= pwc-if.o pwc-misc.o pwc-ctrl.o pwc-uncompress.o pwc-dec1.o pwc-dec23.o pwc-kiara.o pwc-timon.o
+pwc-objs	:= pwc-if.o pwc-misc.o pwc-ctrl.o pwc-uncompress.o pwc-timon.o pwc-kiara.o
 
 obj-$(CONFIG_USB_PWC) += pwc.o
 

drivers/usb/media/pwc/pwc-ctrl.c

@@ -246,7 +246,7 @@ static inline int set_video_mode_Nala(struct pwc_device *pdev, int size, int fra
 	   switch(pdev->type) {
 	     case 645:
 	     case 646:
-	       pwc_dec1_init(pdev->type, pdev->release, buf, pdev->decompress_data);
+/*	       pwc_dec1_init(pdev->type, pdev->release, buf, pdev->decompress_data); */
 	       break;
 
 	     case 675:
@@ -256,7 +256,7 @@ static inline int set_video_mode_Nala(struct pwc_device *pdev, int size, int fra
 	     case 730:
 	     case 740:
 	     case 750:
-	       pwc_dec23_init(pdev->type, pdev->release, buf, pdev->decompress_data);
+/*	       pwc_dec23_init(pdev->type, pdev->release, buf, pdev->decompress_data); */
 	       break;
 	   }
 	}
@@ -318,8 +318,8 @@ static inline int set_video_mode_Timon(struct pwc_device *pdev, int size, int fr
 	if (ret < 0)
 		return ret;
 
-	if (pChoose->bandlength > 0 && pdev->vpalette != VIDEO_PALETTE_RAW)
-	   pwc_dec23_init(pdev->type, pdev->release, buf, pdev->decompress_data);
+/* 	if (pChoose->bandlength > 0 && pdev->vpalette != VIDEO_PALETTE_RAW)
+	   pwc_dec23_init(pdev->type, pdev->release, buf, pdev->decompress_data); */
 
 	pdev->cmd_len = 13;
 	memcpy(pdev->cmd_buf, buf, 13);
@@ -397,8 +397,8 @@ static inline int set_video_mode_Kiara(struct pwc_device *pdev, int size, int fr
 	if (ret < 0)
 		return ret;
 
-	if (pChoose->bandlength > 0 && pdev->vpalette != VIDEO_PALETTE_RAW)
-	  pwc_dec23_init(pdev->type, pdev->release, buf, pdev->decompress_data);
+/*	if (pChoose->bandlength > 0 && pdev->vpalette != VIDEO_PALETTE_RAW)
+	  pwc_dec23_init(pdev->type, pdev->release, buf, pdev->decompress_data); */
 
 	pdev->cmd_len = 12;
 	memcpy(pdev->cmd_buf, buf, 12);

drivers/usb/media/pwc/pwc-dec1.c

-/* Linux driver for Philips webcam
-   Decompression for chipset version 1
-   (C) 2004      Luc Saillard (luc@saillard.org)
-
-   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
-   driver and thus may have bugs that are not present in the original version.
-   Please send bug reports and support requests to <luc@saillard.org>.
-   The decompression routines have been implemented by reverse-engineering the
-   Nemosoft binary pwcx module. Caveat emptor.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-*/
-
-
-
-#include "pwc-dec1.h"
-
-
-void pwc_dec1_init(int type, int release, void *buffer, void *table)
-{
-
-}
-
-void pwc_dec1_exit(void)
-{
-
-
-
-}
-

drivers/usb/media/pwc/pwc-dec1.h

-/* Linux driver for Philips webcam
-   (C) 2004      Luc Saillard (luc@saillard.org)
-
-   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
-   driver and thus may have bugs that are not present in the original version.
-   Please send bug reports and support requests to <luc@saillard.org>.
-   The decompression routines have been implemented by reverse-engineering the
-   Nemosoft binary pwcx module. Caveat emptor.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-*/
-
-
-
-#ifndef PWC_DEC1_H
-#define PWC_DEC1_H
-
-void pwc_dec1_init(int type, int release, void *buffer, void *private_data);
-void pwc_dec1_exit(void);
-
-#endif
-
-
-

drivers/usb/media/pwc/pwc-dec23.h

-/* Linux driver for Philips webcam
-   (C) 2004      Luc Saillard (luc@saillard.org)
-
-   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
-   driver and thus may have bugs that are not present in the original version.
-   Please send bug reports and support requests to <luc@saillard.org>.
-   The decompression routines have been implemented by reverse-engineering the
-   Nemosoft binary pwcx module. Caveat emptor.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-*/
-
-#ifndef PWC_DEC23_H
-#define PWC_DEC23_H
-
-struct pwc_dec23_private
-{
-  unsigned char xx,yy,zz,zzmask;
-
-  unsigned char table_0004[2*0x4000];
-  unsigned char table_8004[2*0x1000];
-  unsigned int  table_a004[256*12];
-
-  unsigned char table_d004[8*256];
-  unsigned int  table_d800[256];
-  unsigned int  table_dc00[256];
-};
-
-
-void pwc_dec23_init(int type, int release, unsigned char *buffer, void *private_data);
-void pwc_dec23_exit(void);
-void pwc_dec23_decompress(const struct pwc_coord *image,
-                            const struct pwc_coord *view,
-			    const struct pwc_coord *offset,
-			    const void *src,
-			    void *dst,
-			    int flags,
-			    const void *data,
-			    int bandlength);
-
-
-
-#endif
-
-
-

drivers/usb/media/pwc/pwc-if.c

@@ -68,8 +68,6 @@
 #include "pwc-ioctl.h"
 #include "pwc-kiara.h"
 #include "pwc-timon.h"
-#include "pwc-dec23.h"
-#include "pwc-dec1.h"
 #include "pwc-uncompress.h"
 
 /* Function prototypes and driver templates */
@@ -322,6 +320,7 @@ static int pwc_allocate_buffers(struct pwc_device *pdev)
 	  case 730:
 	  case 740:
 	  case 750:
+#if 0	  
 	    Trace(TRACE_MEMORY,"private_data(%zu)\n",sizeof(struct pwc_dec23_private));
 	    kbuf = kmalloc(sizeof(struct pwc_dec23_private), GFP_KERNEL);	/* Timon & Kiara */
 	    break;
@@ -330,6 +329,8 @@ static int pwc_allocate_buffers(struct pwc_device *pdev)
 	    /* TODO & FIXME */
 	    kbuf = kmalloc(sizeof(struct pwc_dec23_private), GFP_KERNEL);
 	    break;
+#endif	 
+	;
 	 }
 	if (kbuf == NULL) {
 	   Err("Failed to allocate decompress table.\n");
@@ -1131,11 +1132,11 @@ static int pwc_video_close(struct inode *inode, struct file *file)
 	  case 730:
 	  case 740:
 	  case 750:
-	    pwc_dec23_exit();	/* Timon & Kiara */
+/*	    pwc_dec23_exit();	*//* Timon & Kiara */
 	    break;
 	  case 645:
 	  case 646:
-	    pwc_dec1_exit();
+/*	    pwc_dec1_exit(); */
 	    break;
 	 }
 

drivers/usb/media/pwc/pwc-uncompress.c

@@ -122,6 +122,7 @@ int pwc_decompress(struct pwc_device *pdev)
 
 		switch (pdev->type)
 		 {
+#if 0		 
 		  case 675:
 		  case 680:
 		  case 690:
@@ -137,6 +138,7 @@ int pwc_decompress(struct pwc_device *pdev)
 		  case 645:
 		  case 646:
 		    /* TODO & FIXME */
+#endif		    
 		    return -ENXIO; /* No such device or address: missing decompressor */
 		    break;
 		 }

fs/xfs/linux-2.6/xfs_aops.c

@@ -886,7 +886,6 @@ xfs_page_state_convert(
 		SetPageUptodate(page);
 
 	if (startio) {
-		WARN_ON(page_dirty);
 		xfs_submit_page(page, wbc, bh_arr, cnt, 0, !page_dirty);
 	}
 

fs/xfs/linux-2.6/xfs_file.c

@@ -565,7 +565,7 @@ struct file_operations linvfs_file_operations = {
 	.sendfile	= linvfs_sendfile,
 	.unlocked_ioctl	= linvfs_ioctl,
 #ifdef CONFIG_COMPAT
-	.compat_ioctl   = xfs_compat_ioctl,
+	.compat_ioctl	= linvfs_compat_ioctl,
 #endif
 	.mmap		= linvfs_file_mmap,
 	.open		= linvfs_open,
@@ -587,7 +587,7 @@ struct file_operations linvfs_invis_file_operations = {
 	.sendfile	= linvfs_sendfile,
 	.unlocked_ioctl	= linvfs_ioctl_invis,
 #ifdef CONFIG_COMPAT
-	.compat_ioctl   = xfs_compat_invis_ioctl,
+	.compat_ioctl	= linvfs_compat_invis_ioctl,
 #endif
 	.mmap		= linvfs_file_mmap,
 	.open		= linvfs_open,
@@ -600,6 +600,9 @@ struct file_operations linvfs_dir_operations = {
 	.read		= generic_read_dir,
 	.readdir	= linvfs_readdir,
 	.unlocked_ioctl	= linvfs_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= linvfs_compat_ioctl,
+#endif
 	.fsync		= linvfs_fsync,
 };
 

fs/xfs/linux-2.6/xfs_ioctl32.c

 /*
- * Copyright (c) 2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2004-2005 Silicon Graphics, Inc.  All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2 of the GNU General Public License as
@@ -58,8 +58,9 @@ typedef struct xfs_fsop_bulkreq32 {
 	__s32		ocount;		/* output count pointer		*/
 } xfs_fsop_bulkreq32_t;
 
-static unsigned long
-xfs_ioctl32_bulkstat(unsigned long arg)
+STATIC unsigned long
+xfs_ioctl32_bulkstat(
+	unsigned long		arg)
 {
 	xfs_fsop_bulkreq32_t	__user *p32 = (void __user *)arg;
 	xfs_fsop_bulkreq_t	__user *p = compat_alloc_user_space(sizeof(*p));
@@ -78,11 +79,11 @@ xfs_ioctl32_bulkstat(unsigned long arg)
 }
 #endif
 
-static long
-__xfs_compat_ioctl(int mode, struct file *f, unsigned cmd, unsigned long arg)
+STATIC long
+__linvfs_compat_ioctl(int mode, struct file *f, unsigned cmd, unsigned long arg)
 {
 	int		error;
-	struct inode *inode = f->f_dentry->d_inode;
+	struct		inode *inode = f->f_dentry->d_inode;
 	vnode_t		*vp = LINVFS_GET_VP(inode);
 
 	switch (cmd) {
@@ -152,12 +153,20 @@ __xfs_compat_ioctl(int mode, struct file *f, unsigned cmd, unsigned long arg)
 	return error;
 }
 
-long xfs_compat_ioctl(struct file *f, unsigned cmd, unsigned long arg)
+long
+linvfs_compat_ioctl(
+	struct file		*f,
+	unsigned		cmd,
+	unsigned long		arg)
 {
-	return __xfs_compat_ioctl(0, f, cmd, arg);
+	return __linvfs_compat_ioctl(0, f, cmd, arg);
 }
 
-long xfs_compat_invis_ioctl(struct file *f, unsigned cmd, unsigned long arg)
+long
+linvfs_compat_invis_ioctl(
+	struct file		*f,
+	unsigned		cmd,
+	unsigned long		arg)
 {
-	return __xfs_compat_ioctl(IO_INVIS, f, cmd, arg);
+	return __linvfs_compat_ioctl(IO_INVIS, f, cmd, arg);
 }

fs/xfs/linux-2.6/xfs_ioctl32.h

 /*
- * Copyright (c) 2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2004-2005 Silicon Graphics, Inc.  All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2 of the GNU General Public License as
@@ -30,5 +30,5 @@
  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  */
 
-long xfs_compat_ioctl(struct file *f, unsigned cmd, unsigned long arg);
-long xfs_compat_invis_ioctl(struct file *f, unsigned cmd, unsigned long arg);
+long linvfs_compat_ioctl(struct file *f, unsigned cmd, unsigned long arg);
+long linvfs_compat_invis_ioctl(struct file *f, unsigned cmd, unsigned long arg);

fs/xfs/linux-2.6/xfs_super.c

 /*
- * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.  All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2 of the GNU General Public License as
@@ -66,7 +66,6 @@
 #include "xfs_buf_item.h"
 #include "xfs_utils.h"
 #include "xfs_version.h"
-#include "xfs_ioctl32.h"
 
 #include <linux/namei.h>
 #include <linux/init.h>

fs/xfs/xfs_iomap.c

@@ -278,7 +278,9 @@ phase2:
 	switch (flags & (BMAPI_WRITE|BMAPI_ALLOCATE|BMAPI_UNWRITTEN)) {
 	case BMAPI_WRITE:
 		/* If we found an extent, return it */
-		if (nimaps && (imap.br_startblock != HOLESTARTBLOCK)) {
+		if (nimaps &&
+		    (imap.br_startblock != HOLESTARTBLOCK) && 
+		    (imap.br_startblock != DELAYSTARTBLOCK)) {
 			xfs_iomap_map_trace(XFS_IOMAP_WRITE_MAP, io,
 					offset, count, iomapp, &imap, flags);
 			break;

include/asm-i386/linkage.h

@@ -5,9 +5,7 @@
 #define FASTCALL(x)	x __attribute__((regparm(3)))
 #define fastcall	__attribute__((regparm(3)))
 
-#ifdef CONFIG_REGPARM
-# define prevent_tail_call(ret) __asm__ ("" : "=r" (ret) : "0" (ret))
-#endif
+#define prevent_tail_call(ret) __asm__ ("" : "=r" (ret) : "0" (ret))
 
 #ifdef CONFIG_X86_ALIGNMENT_16
 #define __ALIGN .align 16,0x90

include/linux/acpi.h

@@ -25,6 +25,8 @@
 #ifndef _LINUX_ACPI_H
 #define _LINUX_ACPI_H
 
+#ifdef	CONFIG_ACPI
+
 #ifndef _LINUX
 #define _LINUX
 #endif
@@ -533,4 +535,5 @@ static inline int acpi_get_pxm(acpi_handle handle)
 
 extern int pnpacpi_disabled;
 
-#endif /*_LINUX_ACPI_H*/
+#endif	/* CONFIG_ACPI */
+#endif	/*_LINUX_ACPI_H*/

kernel/cpuset.c

@@ -166,9 +166,8 @@ static struct super_block *cpuset_sb = NULL;
  * The hooks from fork and exit, cpuset_fork() and cpuset_exit(), don't
  * (usually) grab cpuset_sem.  These are the two most performance
  * critical pieces of code here.  The exception occurs on exit(),
- * if the last task using a cpuset exits, and the cpuset was marked
- * notify_on_release.  In that case, the cpuset_sem is taken, the
- * path to the released cpuset calculated, and a usermode call made
+ * when a task in a notify_on_release cpuset exits.  Then cpuset_sem
+ * is taken, and if the cpuset count is zero, a usermode call made
  * to /sbin/cpuset_release_agent with the name of the cpuset (path
  * relative to the root of cpuset file system) as the argument.
  *
@@ -1404,6 +1403,18 @@ void cpuset_fork(struct task_struct *tsk)
  *
  * Description: Detach cpuset from @tsk and release it.
  *
+ * Note that cpusets marked notify_on_release force every task
+ * in them to take the global cpuset_sem semaphore when exiting.
+ * This could impact scaling on very large systems.  Be reluctant
+ * to use notify_on_release cpusets where very high task exit
+ * scaling is required on large systems.
+ *
+ * Don't even think about derefencing 'cs' after the cpuset use
+ * count goes to zero, except inside a critical section guarded
+ * by the cpuset_sem semaphore.  If you don't hold cpuset_sem,
+ * then a zero cpuset use count is a license to any other task to
+ * nuke the cpuset immediately.
+ *
  **/
 
 void cpuset_exit(struct task_struct *tsk)
@@ -1415,10 +1426,13 @@ void cpuset_exit(struct task_struct *tsk)
 	tsk->cpuset = NULL;
 	task_unlock(tsk);
 
-	if (atomic_dec_and_test(&cs->count)) {
+	if (notify_on_release(cs)) {
 		down(&cpuset_sem);
-		check_for_release(cs);
+		if (atomic_dec_and_test(&cs->count))
+			check_for_release(cs);
 		up(&cpuset_sem);
+	} else {
+		atomic_dec(&cs->count);
 	}
 }