Merge branch 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

* 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: nfs_updatepage(): don't mark page as dirty if an error occurred
  NFS: Fix filehandle size comparisons in the mount code
  NFS: Reduce the NFS mount code stack usage.
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index c8a56e4..c048de3 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1228,6 +1228,11 @@
 	if (xen_feature(XENFEAT_supervisor_mode_kernel))
 		pv_info.kernel_rpl = 0;
 
+	/* Prevent unwanted bits from being set in PTEs. */
+	__supported_pte_mask &= ~_PAGE_GLOBAL;
+	if (!is_initial_xendomain())
+		__supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
+
 	/* set the limit of our address space */
 	xen_reserve_top();
 
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 3525ef5..265601d 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -179,48 +179,54 @@
 		preempt_enable();
 }
 
+/* Assume pteval_t is equivalent to all the other *val_t types. */
+static pteval_t pte_mfn_to_pfn(pteval_t val)
+{
+	if (val & _PAGE_PRESENT) {
+		unsigned long mfn = (val & PTE_MASK) >> PAGE_SHIFT;
+		pteval_t flags = val & ~PTE_MASK;
+		val = (mfn_to_pfn(mfn) << PAGE_SHIFT) | flags;
+	}
+
+	return val;
+}
+
+static pteval_t pte_pfn_to_mfn(pteval_t val)
+{
+	if (val & _PAGE_PRESENT) {
+		unsigned long pfn = (val & PTE_MASK) >> PAGE_SHIFT;
+		pteval_t flags = val & ~PTE_MASK;
+		val = (pfn_to_mfn(pfn) << PAGE_SHIFT) | flags;
+	}
+
+	return val;
+}
+
 pteval_t xen_pte_val(pte_t pte)
 {
-	pteval_t ret = pte.pte;
-
-	if (ret & _PAGE_PRESENT)
-		ret = machine_to_phys(XMADDR(ret)).paddr | _PAGE_PRESENT;
-
-	return ret;
+	return pte_mfn_to_pfn(pte.pte);
 }
 
 pgdval_t xen_pgd_val(pgd_t pgd)
 {
-	pgdval_t ret = pgd.pgd;
-	if (ret & _PAGE_PRESENT)
-		ret = machine_to_phys(XMADDR(ret)).paddr | _PAGE_PRESENT;
-	return ret;
+	return pte_mfn_to_pfn(pgd.pgd);
 }
 
 pte_t xen_make_pte(pteval_t pte)
 {
-	if (pte & _PAGE_PRESENT) {
-		pte = phys_to_machine(XPADDR(pte)).maddr;
-		pte &= ~(_PAGE_PCD | _PAGE_PWT);
-	}
-
-	return (pte_t){ .pte = pte };
+	pte = pte_pfn_to_mfn(pte);
+	return native_make_pte(pte);
 }
 
 pgd_t xen_make_pgd(pgdval_t pgd)
 {
-	if (pgd & _PAGE_PRESENT)
-		pgd = phys_to_machine(XPADDR(pgd)).maddr;
-
-	return (pgd_t){ pgd };
+	pgd = pte_pfn_to_mfn(pgd);
+	return native_make_pgd(pgd);
 }
 
 pmdval_t xen_pmd_val(pmd_t pmd)
 {
-	pmdval_t ret = native_pmd_val(pmd);
-	if (ret & _PAGE_PRESENT)
-		ret = machine_to_phys(XMADDR(ret)).paddr | _PAGE_PRESENT;
-	return ret;
+	return pte_mfn_to_pfn(pmd.pmd);
 }
 #ifdef CONFIG_X86_PAE
 void xen_set_pud(pud_t *ptr, pud_t val)
@@ -267,9 +273,7 @@
 
 pmd_t xen_make_pmd(pmdval_t pmd)
 {
-	if (pmd & _PAGE_PRESENT)
-		pmd = phys_to_machine(XPADDR(pmd)).maddr;
-
+	pmd = pte_pfn_to_mfn(pmd);
 	return native_make_pmd(pmd);
 }
 #else  /* !PAE */
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index 288d587..3175e97 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -17,7 +17,7 @@
 
 	__FINIT
 
-.pushsection .bss.page_aligned
+.pushsection .text
 	.align PAGE_SIZE_asm
 ENTRY(hypercall_page)
 	.skip 0x1000
diff --git a/drivers/infiniband/hw/mthca/mthca_memfree.c b/drivers/infiniband/hw/mthca/mthca_memfree.c
index b224079..d5862e5 100644
--- a/drivers/infiniband/hw/mthca/mthca_memfree.c
+++ b/drivers/infiniband/hw/mthca/mthca_memfree.c
@@ -109,7 +109,11 @@
 {
 	struct page *page;
 
-	page = alloc_pages(gfp_mask, order);
+	/*
+	 * Use __GFP_ZERO because buggy firmware assumes ICM pages are
+	 * cleared, and subtle failures are seen if they aren't.
+	 */
+	page = alloc_pages(gfp_mask | __GFP_ZERO, order);
 	if (!page)
 		return -ENOMEM;
 
diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c
index 5126d5d..2e554a4 100644
--- a/drivers/lguest/x86/core.c
+++ b/drivers/lguest/x86/core.c
@@ -176,7 +176,7 @@
 	 * we set it now, so we can trap and pass that trap to the Guest if it
 	 * uses the FPU. */
 	if (cpu->ts)
-		lguest_set_ts();
+		unlazy_fpu(current);
 
 	/* SYSENTER is an optimized way of doing system calls.  We can't allow
 	 * it because it always jumps to privilege level 0.  A normal Guest
@@ -196,6 +196,10 @@
 	 * trap made the switcher code come back, and an error code which some
 	 * traps set.  */
 
+	 /* Restore SYSENTER if it's supposed to be on. */
+	 if (boot_cpu_has(X86_FEATURE_SEP))
+		wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
+
 	/* If the Guest page faulted, then the cr2 register will tell us the
 	 * bad virtual address.  We have to grab this now, because once we
 	 * re-enable interrupts an interrupt could fault and thus overwrite
@@ -203,13 +207,12 @@
 	if (cpu->regs->trapnum == 14)
 		cpu->arch.last_pagefault = read_cr2();
 	/* Similarly, if we took a trap because the Guest used the FPU,
-	 * we have to restore the FPU it expects to see. */
+	 * we have to restore the FPU it expects to see.
+	 * math_state_restore() may sleep and we may even move off to
+	 * a different CPU. So all the critical stuff should be done
+	 * before this.  */
 	else if (cpu->regs->trapnum == 7)
 		math_state_restore();
-
-	/* Restore SYSENTER if it's supposed to be on. */
-	if (boot_cpu_has(X86_FEATURE_SEP))
-		wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
 }
 
 /*H:130 Now we've examined the hypercall code; our Guest can make requests.
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 4f0f22b..76e5b73 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -529,7 +529,7 @@
 
 #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
 		/* Clear master flag /before/ clearing selector flag. */
-		rmb();
+		wmb();
 #endif
 		pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
 		while (pending_words != 0) {
diff --git a/kernel/futex.c b/kernel/futex.c
index 449def8..7d1136e 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1096,21 +1096,64 @@
  * private futexes.
  */
 static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
-				struct task_struct *newowner)
+				struct task_struct *newowner,
+				struct rw_semaphore *fshared)
 {
 	u32 newtid = task_pid_vnr(newowner) | FUTEX_WAITERS;
 	struct futex_pi_state *pi_state = q->pi_state;
+	struct task_struct *oldowner = pi_state->owner;
 	u32 uval, curval, newval;
-	int ret;
+	int ret, attempt = 0;
 
 	/* Owner died? */
+	if (!pi_state->owner)
+		newtid |= FUTEX_OWNER_DIED;
+
+	/*
+	 * We are here either because we stole the rtmutex from the
+	 * pending owner or we are the pending owner which failed to
+	 * get the rtmutex. We have to replace the pending owner TID
+	 * in the user space variable. This must be atomic as we have
+	 * to preserve the owner died bit here.
+	 *
+	 * Note: We write the user space value _before_ changing the
+	 * pi_state because we can fault here. Imagine swapped out
+	 * pages or a fork, which was running right before we acquired
+	 * mmap_sem, that marked all the anonymous memory readonly for
+	 * cow.
+	 *
+	 * Modifying pi_state _before_ the user space value would
+	 * leave the pi_state in an inconsistent state when we fault
+	 * here, because we need to drop the hash bucket lock to
+	 * handle the fault. This might be observed in the PID check
+	 * in lookup_pi_state.
+	 */
+retry:
+	if (get_futex_value_locked(&uval, uaddr))
+		goto handle_fault;
+
+	while (1) {
+		newval = (uval & FUTEX_OWNER_DIED) | newtid;
+
+		curval = cmpxchg_futex_value_locked(uaddr, uval, newval);
+
+		if (curval == -EFAULT)
+			goto handle_fault;
+		if (curval == uval)
+			break;
+		uval = curval;
+	}
+
+	/*
+	 * We fixed up user space. Now we need to fix the pi_state
+	 * itself.
+	 */
 	if (pi_state->owner != NULL) {
 		spin_lock_irq(&pi_state->owner->pi_lock);
 		WARN_ON(list_empty(&pi_state->list));
 		list_del_init(&pi_state->list);
 		spin_unlock_irq(&pi_state->owner->pi_lock);
-	} else
-		newtid |= FUTEX_OWNER_DIED;
+	}
 
 	pi_state->owner = newowner;
 
@@ -1118,26 +1161,35 @@
 	WARN_ON(!list_empty(&pi_state->list));
 	list_add(&pi_state->list, &newowner->pi_state_list);
 	spin_unlock_irq(&newowner->pi_lock);
+	return 0;
 
 	/*
-	 * We own it, so we have to replace the pending owner
-	 * TID. This must be atomic as we have preserve the
-	 * owner died bit here.
+	 * To handle the page fault we need to drop the hash bucket
+	 * lock here. That gives the other task (either the pending
+	 * owner itself or the task which stole the rtmutex) the
+	 * chance to try the fixup of the pi_state. So once we are
+	 * back from handling the fault we need to check the pi_state
+	 * after reacquiring the hash bucket lock and before trying to
+	 * do another fixup. When the fixup has been done already we
+	 * simply return.
 	 */
-	ret = get_futex_value_locked(&uval, uaddr);
+handle_fault:
+	spin_unlock(q->lock_ptr);
 
-	while (!ret) {
-		newval = (uval & FUTEX_OWNER_DIED) | newtid;
+	ret = futex_handle_fault((unsigned long)uaddr, fshared, attempt++);
 
-		curval = cmpxchg_futex_value_locked(uaddr, uval, newval);
+	spin_lock(q->lock_ptr);
 
-		if (curval == -EFAULT)
-			ret = -EFAULT;
-		if (curval == uval)
-			break;
-		uval = curval;
-	}
-	return ret;
+	/*
+	 * Check if someone else fixed it for us:
+	 */
+	if (pi_state->owner != oldowner)
+		return 0;
+
+	if (ret)
+		return ret;
+
+	goto retry;
 }
 
 /*
@@ -1507,7 +1559,7 @@
 		 * that case:
 		 */
 		if (q.pi_state->owner != curr)
-			ret = fixup_pi_state_owner(uaddr, &q, curr);
+			ret = fixup_pi_state_owner(uaddr, &q, curr, fshared);
 	} else {
 		/*
 		 * Catch the rare case, where the lock was released
@@ -1539,7 +1591,8 @@
 				int res;
 
 				owner = rt_mutex_owner(&q.pi_state->pi_mutex);
-				res = fixup_pi_state_owner(uaddr, &q, owner);
+				res = fixup_pi_state_owner(uaddr, &q, owner,
+							   fshared);
 
 				/* propagate -EFAULT, if the fixup failed */
 				if (res)
diff --git a/kernel/sched.c b/kernel/sched.c
index b048ad8..3aaa5c8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4398,22 +4398,20 @@
 			     signal_pending(current)) ||
 			    (state == TASK_KILLABLE &&
 			     fatal_signal_pending(current))) {
-				__remove_wait_queue(&x->wait, &wait);
-				return -ERESTARTSYS;
+				timeout = -ERESTARTSYS;
+				break;
 			}
 			__set_current_state(state);
 			spin_unlock_irq(&x->wait.lock);
 			timeout = schedule_timeout(timeout);
 			spin_lock_irq(&x->wait.lock);
-			if (!timeout) {
-				__remove_wait_queue(&x->wait, &wait);
-				return timeout;
-			}
-		} while (!x->done);
+		} while (!x->done && timeout);
 		__remove_wait_queue(&x->wait, &wait);
+		if (!x->done)
+			return timeout;
 	}
 	x->done--;
-	return timeout;
+	return timeout ?: 1;
 }
 
 static long __sched
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 1dad5bb..0f3c191 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -250,7 +250,8 @@
 			if (rt_rq->rt_time || rt_rq->rt_nr_running)
 				idle = 0;
 			spin_unlock(&rt_rq->rt_runtime_lock);
-		}
+		} else if (rt_rq->rt_nr_running)
+			idle = 0;
 
 		if (enqueue)
 			sched_rt_rq_enqueue(rt_rq);
diff --git a/sound/isa/sb/sb_mixer.c b/sound/isa/sb/sb_mixer.c
index 91d1422..73d4572 100644
--- a/sound/isa/sb/sb_mixer.c
+++ b/sound/isa/sb/sb_mixer.c
@@ -925,7 +925,7 @@
 static void save_mixer(struct snd_sb *chip, unsigned char *regs, int num_regs)
 {
 	unsigned char *val = chip->saved_regs;
-	snd_assert(num_regs > ARRAY_SIZE(chip->saved_regs), return);
+	snd_assert(num_regs <= ARRAY_SIZE(chip->saved_regs), return);
 	for (; num_regs; num_regs--)
 		*val++ = snd_sbmixer_read(chip, *regs++);
 }
@@ -933,7 +933,7 @@
 static void restore_mixer(struct snd_sb *chip, unsigned char *regs, int num_regs)
 {
 	unsigned char *val = chip->saved_regs;
-	snd_assert(num_regs > ARRAY_SIZE(chip->saved_regs), return);
+	snd_assert(num_regs <= ARRAY_SIZE(chip->saved_regs), return);
 	for (; num_regs; num_regs--)
 		snd_sbmixer_write(chip, *regs++, *val++);
 }
diff --git a/sound/pci/aw2/aw2-alsa.c b/sound/pci/aw2/aw2-alsa.c
index 56f87cd..3f00ddf 100644
--- a/sound/pci/aw2/aw2-alsa.c
+++ b/sound/pci/aw2/aw2-alsa.c
@@ -316,6 +316,8 @@
 		return -ENOMEM;
 	}
 
+	/* (2) initialization of the chip hardware */
+	snd_aw2_saa7146_setup(&chip->saa7146, chip->iobase_virt);
 
 	if (request_irq(pci->irq, snd_aw2_saa7146_interrupt,
 			IRQF_SHARED, "Audiowerk2", chip)) {
@@ -329,8 +331,6 @@
 	}
 	chip->irq = pci->irq;
 
-	/* (2) initialization of the chip hardware */
-	snd_aw2_saa7146_setup(&chip->saa7146, chip->iobase_virt);
 	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
 	if (err < 0) {
 		free_irq(chip->irq, (void *)chip);