From 58a84aa92723d1ac3e1cc4e3b0ff49291663f7e1 Mon Sep 17 00:00:00 2001 From: Youquan Song Date: Thu, 8 Dec 2011 14:34:18 -0800 Subject: thp: set compound tail page _count to zero Commit 70b50f94f1644 ("mm: thp: tail page refcounting fix") keeps all page_tail->_count zero at all times. But the current kernel does not set page_tail->_count to zero if a 1GB page is utilized. So when an IOMMU 1GB page is used by KVM, it wil result in a kernel oops because a tail page's _count does not equal zero. kernel BUG at include/linux/mm.h:386! invalid opcode: 0000 [#1] SMP Call Trace: gup_pud_range+0xb8/0x19d get_user_pages_fast+0xcb/0x192 ? trace_hardirqs_off+0xd/0xf hva_to_pfn+0x119/0x2f2 gfn_to_pfn_memslot+0x2c/0x2e kvm_iommu_map_pages+0xfd/0x1c1 kvm_iommu_map_memslots+0x7c/0xbd kvm_iommu_map_guest+0xaa/0xbf kvm_vm_ioctl_assigned_device+0x2ef/0xa47 kvm_vm_ioctl+0x36c/0x3a2 do_vfs_ioctl+0x49e/0x4e4 sys_ioctl+0x5a/0x7c system_call_fastpath+0x16/0x1b RIP gup_huge_pud+0xf2/0x159 Signed-off-by: Youquan Song Reviewed-by: Andrea Arcangeli Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 1 + 1 file changed, 1 insertion(+) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index bb28a5f9db8d..73f17c0293c0 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -576,6 +576,7 @@ static void prep_compound_gigantic_page(struct page *page, unsigned long order) __SetPageHead(page); for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { __SetPageTail(p); + set_page_count(p, 0); p->first_page = page; } } -- cgit From 10fbcf4c6cb122005cdf36fc24d7683da92c7a27 Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Wed, 21 Dec 2011 14:48:43 -0800 Subject: convert 'memory' sysdev_class to a regular subsystem This moves the 'memory sysdev_class' over to a regular 'memory' subsystem and converts the devices to regular devices. The sysdev drivers are implemented as subsystem interfaces now. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- mm/hugetlb.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index dae27ba3be2c..ad713e2d61bc 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1591,9 +1591,9 @@ static void __init hugetlb_sysfs_init(void) /* * node_hstate/s - associate per node hstate attributes, via their kobjects, - * with node sysdevs in node_devices[] using a parallel array. The array - * index of a node sysdev or _hstate == node id. - * This is here to avoid any static dependency of the node sysdev driver, in + * with node devices in node_devices[] using a parallel array. The array + * index of a node device or _hstate == node id. + * This is here to avoid any static dependency of the node device driver, in * the base kernel, on the hugetlb module. */ struct node_hstate { @@ -1603,7 +1603,7 @@ struct node_hstate { struct node_hstate node_hstates[MAX_NUMNODES]; /* - * A subset of global hstate attributes for node sysdevs + * A subset of global hstate attributes for node devices */ static struct attribute *per_node_hstate_attrs[] = { &nr_hugepages_attr.attr, @@ -1617,7 +1617,7 @@ static struct attribute_group per_node_hstate_attr_group = { }; /* - * kobj_to_node_hstate - lookup global hstate for node sysdev hstate attr kobj. + * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. * Returns node id via non-NULL nidp. */ static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) @@ -1640,13 +1640,13 @@ static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) } /* - * Unregister hstate attributes from a single node sysdev. + * Unregister hstate attributes from a single node device. * No-op if no hstate attributes attached. */ void hugetlb_unregister_node(struct node *node) { struct hstate *h; - struct node_hstate *nhs = &node_hstates[node->sysdev.id]; + struct node_hstate *nhs = &node_hstates[node->dev.id]; if (!nhs->hugepages_kobj) return; /* no hstate attributes */ @@ -1662,7 +1662,7 @@ void hugetlb_unregister_node(struct node *node) } /* - * hugetlb module exit: unregister hstate attributes from node sysdevs + * hugetlb module exit: unregister hstate attributes from node devices * that have them. */ static void hugetlb_unregister_all_nodes(void) @@ -1670,7 +1670,7 @@ static void hugetlb_unregister_all_nodes(void) int nid; /* - * disable node sysdev registrations. + * disable node device registrations. */ register_hugetlbfs_with_node(NULL, NULL); @@ -1682,20 +1682,20 @@ static void hugetlb_unregister_all_nodes(void) } /* - * Register hstate attributes for a single node sysdev. + * Register hstate attributes for a single node device. * No-op if attributes already registered. */ void hugetlb_register_node(struct node *node) { struct hstate *h; - struct node_hstate *nhs = &node_hstates[node->sysdev.id]; + struct node_hstate *nhs = &node_hstates[node->dev.id]; int err; if (nhs->hugepages_kobj) return; /* already allocated */ nhs->hugepages_kobj = kobject_create_and_add("hugepages", - &node->sysdev.kobj); + &node->dev.kobj); if (!nhs->hugepages_kobj) return; @@ -1706,7 +1706,7 @@ void hugetlb_register_node(struct node *node) if (err) { printk(KERN_ERR "Hugetlb: Unable to add hstate %s" " for node %d\n", - h->name, node->sysdev.id); + h->name, node->dev.id); hugetlb_unregister_node(node); break; } @@ -1715,8 +1715,8 @@ void hugetlb_register_node(struct node *node) /* * hugetlb init time: register hstate attributes for all registered node - * sysdevs of nodes that have memory. All on-line nodes should have - * registered their associated sysdev by this time. + * devices of nodes that have memory. All on-line nodes should have + * registered their associated device by this time. */ static void hugetlb_register_all_nodes(void) { @@ -1724,12 +1724,12 @@ static void hugetlb_register_all_nodes(void) for_each_node_state(nid, N_HIGH_MEMORY) { struct node *node = &node_devices[nid]; - if (node->sysdev.id == nid) + if (node->dev.id == nid) hugetlb_register_node(node); } /* - * Let the node sysdev driver know we're here so it can + * Let the node device driver know we're here so it can * [un]register hstate attributes on node hotplug. */ register_hugetlbfs_with_node(hugetlb_register_node, -- cgit From b0365c8d0cb6e79eb5f21418ae61ab511f31b575 Mon Sep 17 00:00:00 2001 From: Hillf Danton Date: Wed, 28 Dec 2011 15:57:16 -0800 Subject: mm: hugetlb: fix non-atomic enqueue of huge page If a huge page is enqueued under the protection of hugetlb_lock, then the operation is atomic and safe. Signed-off-by: Hillf Danton Reviewed-by: Michal Hocko Acked-by: KAMEZAWA Hiroyuki Cc: [2.6.37+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 73f17c0293c0..2316840b337a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -901,7 +901,6 @@ retry: h->resv_huge_pages += delta; ret = 0; - spin_unlock(&hugetlb_lock); /* Free the needed pages to the hugetlb pool */ list_for_each_entry_safe(page, tmp, &surplus_list, lru) { if ((--needed) < 0) @@ -915,6 +914,7 @@ retry: VM_BUG_ON(page_count(page)); enqueue_huge_page(h, page); } + spin_unlock(&hugetlb_lock); /* Free unnecessary surplus pages to the buddy allocator */ free: -- cgit