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2008-04-18alloc_percpu() fails to allocate percpu dataEric Dumazet
upstream commit: be852795e1c8d3829ddf3cb1ce806113611fa555 Some oprofile results obtained while using tbench on a 2x2 cpu machine were very surprising. For example, loopback_xmit() function was using high number of cpu cycles to perform the statistic updates, supposed to be real cheap since they use percpu data pcpu_lstats = netdev_priv(dev); lb_stats = per_cpu_ptr(pcpu_lstats, smp_processor_id()); lb_stats->packets++; /* HERE : serious contention */ lb_stats->bytes += skb->len; struct pcpu_lstats is a small structure containing two longs. It appears that on my 32bits platform, alloc_percpu(8) allocates a single cache line, instead of giving to each cpu a separate cache line. Using the following patch gave me impressive boost in various benchmarks ( 6 % in tbench) (all percpu_counters hit this bug too) Long term fix (ie >= 2.6.26) would be to let each CPU allocate their own block of memory, so that we dont need to roudup sizes to L1_CACHE_BYTES, or merging the SGI stuff of course... Note : SLUB vs SLAB is important here to *show* the improvement, since they dont have the same minimum allocation sizes (8 bytes vs 32 bytes). This could very well explain regressions some guys reported when they switched to SLUB. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-04-18PERCPU : __percpu_alloc_mask() can dynamically size percpu_data storageEric Dumazet
upstream commit: b3242151906372f30f57feaa43b4cac96a23edb1 Instead of allocating a fix sized array of NR_CPUS pointers for percpu_data, we can use nr_cpu_ids, which is generally < NR_CPUS. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-04-18slab: fix cache_cache bootstrap in kmem_cache_init()Daniel Yeisley
upstream commit: ec1f5eeeb5a79a0d48036de649a3498da42db565 Commit 556a169dab38b5100df6f4a45b655dddd3db94c1 ("slab: fix bootstrap on memoryless node") introduced bootstrap-time cache_cache list3s for all nodes but forgot that initkmem_list3 needs to be accessed by [somevalue + node]. This patch fixes list_add() corruption in mm/slab.c seen on the ES7000. Cc: Mel Gorman <mel@csn.ul.ie> Cc: Olaf Hering <olaf@aepfle.de> Signed-off-by: Dan Yeisley <dan.yeisley@unisys.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-03-24slab: NUMA slab allocator migration bugfixJoe Korty
NUMA slab allocator cpu migration bugfix The NUMA slab allocator (specifically, cache_alloc_refill) is not refreshing its local copies of what cpu and what numa node it is on, when it drops and reacquires the irq block that it inherited from its caller. As a result those values become invalid if an attempt to migrate the process to another numa node occured while the irq block had been dropped. The solution is to make cache_alloc_refill reload these variables whenever it drops and reacquires the irq block. The error is very difficult to hit. When it does occur, one gets the following oops + stack traceback bits in check_spinlock_acquired: kernel BUG at mm/slab.c:2417 cache_alloc_refill+0xe6 kmem_cache_alloc+0xd0 ... This patch was developed against 2.6.23, ported to and compiled-tested only against 2.6.25-rc4. Signed-off-by: Joe Korty <joe.korty@ccur.com> Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-03-24hugetlb: ensure we do not reference a surplus page after handing it to buddyAndy Whitcroft
commit: e5df70ab194543522397fa3da8c8f80564a0f7d3 When we free a page via free_huge_page and we detect that we are in surplus the page will be returned to the buddy. After this we no longer own the page. However at the end free_huge_page we clear out our mapping pointer from page private. Even where the page is not a surplus we free the page to the hugepage pool, drop the pool locks and then clear page private. In either case the page may have been reallocated. BAD. Make sure we clear out page private before we free the page. Signed-off-by: Andy Whitcroft <apw@shadowen.org> Acked-by: Adam Litke <agl@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-24iov_iter_advance() fixNick Piggin
commit: f7009264c519603b8ec67c881bd368a56703cfc9 iov_iter_advance() skips over zero-length iovecs, however it does not properly terminate at the end of the iovec array. Fix this by checking against i->count before we skip a zero-length iov. The bug was reproduced with a test program that continually randomly creates iovs to writev. The fix was also verified with the same program and also it could verify that the correct data was contained in the file after each writev. Signed-off-by: Nick Piggin <npiggin@suse.de> Tested-by: "Kevin Coffman" <kwc@citi.umich.edu> Cc: "Alexey Dobriyan" <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-25SLUB: Deal with annoying gcc warning on kfree()Christoph Lameter
patch 5bb983b0cce9b7b281af15730f7019116dd42568 in mainline. gcc 4.2 spits out an annoying warning if one casts a const void * pointer to a void * pointer. No warning is generated if the conversion is done through an assignment. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-25Be more robust about bad arguments in get_user_pages()Jonathan Corbet
patch 900cf086fd2fbad07f72f4575449e0d0958f860f in mainline. So I spent a while pounding my head against my monitor trying to figure out the vmsplice() vulnerability - how could a failure to check for *read* access turn into a root exploit? It turns out that it's a buffer overflow problem which is made easy by the way get_user_pages() is coded. In particular, "len" is a signed int, and it is only checked at the *end* of a do {} while() loop. So, if it is passed in as zero, the loop will execute once and decrement len to -1. At that point, the loop will proceed until the next invalid address is found; in the process, it will likely overflow the pages array passed in to get_user_pages(). I think that, if get_user_pages() has been asked to grab zero pages, that's what it should do. Thus this patch; it is, among other things, enough to block the (already fixed) root exploit and any others which might be lurking in similar code. I also think that the number of pages should be unsigned, but changing the prototype of this function probably requires some more careful review. Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-25hugetlb: add locking for overcommit sysctlNishanth Aravamudan
patch a3d0c6aa1bb342b9b2c7b123b52ac2f48a4d4d0a in mainline. When I replaced hugetlb_dynamic_pool with nr_overcommit_hugepages I used proc_doulongvec_minmax() directly. However, hugetlb.c's locking rules require that all counter modifications occur under the hugetlb_lock. Add a callback into the hugetlb code similar to the one for nr_hugepages. Grab the lock around the manipulation of nr_overcommit_hugepages in proc_doulongvec_minmax(). Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Acked-by: Adam Litke <agl@us.ibm.com> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: William Lee Irwin III <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-08fix writev regression: pan hanging unkillable and un-straceableNick Piggin
patch 124d3b7041f9a0ca7c43a6293e1cae4576c32fd5 in mainline. Frederik Himpe reported an unkillable and un-straceable pan process. Zero length iovecs can go into an infinite loop in writev, because the iovec iterator does not always advance over them. The sequence required to trigger this is not trivial. I think it requires that a zero-length iovec be followed by a non-zero-length iovec which causes a pagefault in the atomic usercopy. This causes the writev code to drop back into single-segment copy mode, which then tries to copy the 0 bytes of the zero-length iovec; a zero length copy looks like a failure though, so it loops. Put a test into iov_iter_advance to catch zero-length iovecs. We could just put the test in the fallback path, but I feel it is more robust to skip over zero-length iovecs throughout the code (iovec iterator may be used in filesystems too, so it should be robust). Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-08sys_remap_file_pages: fix ->vm_file accountingOleg Nesterov
patch 8a459e44ad837018ea5c34a9efe8eb4ad27ded26 in mainline. Fix ->vm_file accounting, mmap_region() may do do_munmap(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-08vm audit: add VM_DONTEXPAND to mmap for drivers that need it (CVE-2008-0007)Nick Piggin
Drivers that register a ->fault handler, but do not range-check the offset argument, must set VM_DONTEXPAND in the vm_flags in order to prevent an expanding mremap from overflowing the resource. I've audited the tree and attempted to fix these problems (usually by adding VM_DONTEXPAND where it is not obvious). Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-08slab: fix bootstrap on memoryless nodePekka J Enberg
[ Upstream commit: 556a169dab38b5100df6f4a45b655dddd3db94c1 ] If the node we're booting on doesn't have memory, bootstrapping kmalloc() caches resorts to fallback_alloc() which requires ->nodelists set for all nodes. Fix that by calling set_up_list3s() for CACHE_CACHE in kmem_cache_init(). As kmem_getpages() is called with GFP_THISNODE set, this used to work before because of breakage in 2.6.22 and before with GFP_THISNODE returning pages from the wrong node if a node had no memory. So it may have worked accidentally and in an unsafe manner because the pages would have been associated with the wrong node which could trigger bug ons and locking troubles. Tested-by: Mel Gorman <mel@csn.ul.ie> Tested-by: Olaf Hering <olaf@aepfle.de> Reviewed-by: Christoph Lameter <clameter@sgi.com> [ With additional one-liner by Olaf Hering - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-01-24slab: partially revert list3 changesMel Gorman
Partial revert the changes made by 04231b3002ac53f8a64a7bd142fde3fa4b6808c6 to the kmem_list3 management. On a machine with a memoryless node, this BUG_ON was triggering static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) { struct list_head *entry; struct slab *slabp; struct kmem_list3 *l3; void *obj; int x; l3 = cachep->nodelists[nodeid]; BUG_ON(!l3); Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Christoph Lameter <clameter@sgi.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Nishanth Aravamudan <nacc@us.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-24fix hugepages leak due to pagetable page sharingLarry Woodman
The shared page table code for hugetlb memory on x86 and x86_64 is causing a leak. When a user of hugepages exits using this code the system leaks some of the hugepages. ------------------------------------------------------- Part of /proc/meminfo just before database startup: HugePages_Total: 5500 HugePages_Free: 5500 HugePages_Rsvd: 0 Hugepagesize: 2048 kB Just before shutdown: HugePages_Total: 5500 HugePages_Free: 4475 HugePages_Rsvd: 0 Hugepagesize: 2048 kB After shutdown: HugePages_Total: 5500 HugePages_Free: 4988 HugePages_Rsvd: 0 Hugepagesize: 2048 kB ---------------------------------------------------------- The problem occurs durring a fork, in copy_hugetlb_page_range(). It locates the dst_pte using huge_pte_alloc(). Since huge_pte_alloc() calls huge_pmd_share() it will share the pmd page if can, yet the main loop in copy_hugetlb_page_range() does a get_page() on every hugepage. This is a violation of the shared hugepmd pagetable protocol and creates additional referenced to the hugepages causing a leak when the unmap of the VMA occurs. We can skip the entire replication of the ptes when the hugepage pagetables are shared. The attached patch skips copying the ptes and the get_page() calls if the hugetlbpage pagetable is shared. [akpm@linux-foundation.org: coding-style cleanups] Signed-off-by: Larry Woodman <lwoodman@redhat.com> Signed-off-by: Adam Litke <agl@us.ibm.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Ken Chen <kenchen@google.com> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: William Lee Irwin III <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-23Update ctime and mtime for memory-mapped filesAnton Salikhmetov
Update ctime and mtime for memory-mapped files at a write access on a present, read-only PTE, as well as at a write on a non-present PTE. Signed-off-by: Anton Salikhmetov <salikhmetov@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-17#ifdef very expensive debug check in page fault pathCarsten Otte
This patch puts #ifdef CONFIG_DEBUG_VM around a check in vm_normal_page that verifies that a pfn is valid. This patch increases performance of the page fault microbenchmark in lmbench by 13% and overall dbench performance by 7% on s390x. pfn_valid() is an expensive operation on s390 that needs a high double digit amount of CPU cycles. Nick Piggin suggested that pfn_valid() involves an array lookup on systems with sparsemem, and therefore is an expensive operation there too. The check looks like a clear debug thing to me, it should never trigger on regular kernels. And if a pte is created for an invalid pfn, we'll find out once the memory gets accessed later on anyway. Please consider inclusion of this patch into mm. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-17mm: fix section mismatch warning in page_alloc.cSam Ravnborg
With CONFIG_HOTPLUG=n and CONFIG_HOTPLUG_CPU=y we saw following warning: WARNING: mm/built-in.o(.text+0x6864): Section mismatch: reference to .init.text: (between 'process_zones' and 'pageset_cpuup_callback') The culprit was zone_batchsize() which were annotated __devinit but used from process_zones() which is annotated __cpuinit. zone_batchsize() are used from another function annotated __meminit so the only valid option is to drop the annotation of zone_batchsize() so we know it is always valid to use it. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-14Revert "writeback: introduce writeback_control.more_io to indicate more io"Linus Torvalds
This reverts commit 2e6883bdf49abd0e7f0d9b6297fc3be7ebb2250b, as requested by Fengguang Wu. It's not quite fully baked yet, and while there are patches around to fix the problems it caused, they should get more testing. Says Fengguang: "I'll resend them both for -mm later on, in a more complete patchset". See http://bugzilla.kernel.org/show_bug.cgi?id=9738 for some of this discussion. Requested-by: Fengguang Wu <wfg@mail.ustc.edu.cn> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-14hugetlbfs: fix quota leakKen Chen
In the error path of both shared and private hugetlb page allocation, the file system quota is never undone, leading to fs quota leak. Fix them up. [akpm@linux-foundation.org: cleanup, micro-optimise] Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Adam Litke <agl@us.ibm.com> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: William Lee Irwin III <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-14quicklists: Only consider memory that can be used with GFP_KERNELChristoph Lameter
Quicklists calculates the size of the quicklists based on the number of free pages. This must be the number of free pages that can be allocated with GFP_KERNEL. node_page_state() includes the pages in ZONE_HIGHMEM and ZONE_MOVABLE which may lead the quicklists to become too large causing OOM. Signed-off-by: Christoph Lameter <clameter@sgi.com> Tested-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-08Fix crash with FLAT_MEMORY and ARCH_PFN_OFFSET != 0Thomas Bogendoerfer
When using FLAT_MEMORY and ARCH_PFN_OFFSET is not 0, the kernel crashes in memmap_init_zone(). This bug got introduced by commit c713216deebd95d2b0ab38fef8bb2361c0180c2d Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Bob Picco <bob.picco@hp.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Andi Kleen <ak@muc.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Keith Mannthey" <kmannth@gmail.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-08xip: fix get_zeroed_page with __GFP_HIGHMEMAkinobu Mita
The use of get_zeroed_page() with __GFP_HIGHMEM is invalid. Use alloc_page() with __GFP_ZERO instead of invalid get_zeroed_page(). (This patch is only compile tested) Cc: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: Hugh Dickins <hugh@veritas.com> Acked-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-02Unify /proc/slabinfo configurationLinus Torvalds
Both SLUB and SLAB really did almost exactly the same thing for /proc/slabinfo setup, using duplicate code and per-allocator #ifdef's. This just creates a common CONFIG_SLABINFO that is enabled by both SLUB and SLAB, and shares all the setup code. Maybe SLOB will want this some day too. Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-01slub: provide /proc/slabinfoPekka J Enberg
This adds a read-only /proc/slabinfo file on SLUB, that makes slabtop work. [ mingo@elte.hu: build fix. ] Cc: Andi Kleen <andi@firstfloor.org> Cc: Christoph Lameter <clameter@sgi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-21SLUB: Improve hackbench speedChristoph Lameter
Increase the mininum number of partial slabs to keep around and put partial slabs to the end of the partial queue so that they can add more objects. Signed-off-by: Christoph Lameter <clameter@sgi.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-19Do dirty page accounting when removing a page from the page cacheLinus Torvalds
Krzysztof Oledzki noticed a dirty page accounting leak on some of his machines, causing the machine to eventually lock up when the kernel decided that there was too much dirty data, but nobody could actually write anything out to fix it. The culprit turns out to be filesystems (cough ext3 with data=journal cough) that re-dirty the page when the "->invalidatepage()" callback is called. Fix it up by doing a final dirty page accounting check when we actually remove the page from the page cache. This fixes bugzilla entry 9182: http://bugzilla.kernel.org/show_bug.cgi?id=9182 Tested-by: Ingo Molnar <mingo@elte.hu> Tested-by: Krzysztof Oledzki <olel@ans.pl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17SLUB: remove useless masking of GFP_ZEROChristoph Lameter
Remove a recently added useless masking of GFP_ZERO. GFP_ZERO is already masked out in new_slab() (See how it calls allocate_slab). No need to do it twice. This reverts the SLUB parts of 7fd272550bd43cc1d7289ef0ab2fa50de137e767. Cc: Matt Mackall <mpm@selenic.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17Revert "hugetlb: Add hugetlb_dynamic_pool sysctl"Nishanth Aravamudan
This reverts commit 54f9f80d6543fb7b157d3b11e2e7911dc1379790 ("hugetlb: Add hugetlb_dynamic_pool sysctl") Given the new sysctl nr_overcommit_hugepages, the boolean dynamic pool sysctl is not needed, as its semantics can be expressed by 0 in the overcommit sysctl (no dynamic pool) and non-0 in the overcommit sysctl (pool enabled). (Needed in 2.6.24 since it reverts a post-2.6.23 userspace-visible change) Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Acked-by: Adam Litke <agl@us.ibm.com> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17hugetlb: introduce nr_overcommit_hugepages sysctlNishanth Aravamudan
hugetlb: introduce nr_overcommit_hugepages sysctl While examining the code to support /proc/sys/vm/hugetlb_dynamic_pool, I became convinced that having a boolean sysctl was insufficient: 1) To support per-node control of hugepages, I have previously submitted patches to add a sysfs attribute related to nr_hugepages. However, with a boolean global value and per-mount quota enforcement constraining the dynamic pool, adding corresponding control of the dynamic pool on a per-node basis seems inconsistent to me. 2) Administration of the hugetlb dynamic pool with multiple hugetlbfs mount points is, arguably, more arduous than it needs to be. Each quota would need to be set separately, and the sum would need to be monitored. To ease the administration, and to help make the way for per-node control of the static & dynamic hugepage pool, I added a separate sysctl, nr_overcommit_hugepages. This value serves as a high watermark for the overall hugepage pool, while nr_hugepages serves as a low watermark. The boolean sysctl can then be removed, as the condition nr_overcommit_hugepages > 0 indicates the same administrative setting as hugetlb_dynamic_pool == 1 Quotas still serve as local enforcement of the size of the pool on a per-mount basis. A few caveats: 1) There is a race whereby the global surplus huge page counter is incremented before a hugepage has allocated. Another process could then try grow the pool, and fail to convert a surplus huge page to a normal huge page and instead allocate a fresh huge page. I believe this is benign, as no memory is leaked (the actual pages are still tracked correctly) and the counters won't go out of sync. 2) Shrinking the static pool while a surplus is in effect will allow the number of surplus huge pages to exceed the overcommit value. As long as this condition holds, however, no more surplus huge pages will be allowed on the system until one of the two sysctls are increased sufficiently, or the surplus huge pages go out of use and are freed. Successfully tested on x86_64 with the current libhugetlbfs snapshot, modified to use the new sysctl. Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Acked-by: Adam Litke <agl@us.ibm.com> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17mm: fix page allocation for larger I/O segmentsMel Gorman
In some cases the IO subsystem is able to merge requests if the pages are adjacent in physical memory. This was achieved in the allocator by having expand() return pages in physically contiguous order in situations were a large buddy was split. However, list-based anti-fragmentation changed the order pages were returned in to avoid searching in buffered_rmqueue() for a page of the appropriate migrate type. This patch restores behaviour of rmqueue_bulk() preserving the physical order of pages returned by the allocator without incurring increased search costs for anti-fragmentation. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Mark Lord <mlord@pobox.com Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17mm/sparse.c: improve the error handling for sparse_add_one_section()WANG Cong
Improve the error handling for mm/sparse.c::sparse_add_one_section(). And I see no reason to check 'usemap' until holding the 'pgdat_resize_lock'. [geoffrey.levand@am.sony.com: sparse_index_init() returns -EEXIST] Cc: Christoph Lameter <clameter@sgi.com> Acked-by: Dave Hansen <haveblue@us.ibm.com> Cc: Rik van Riel <riel@redhat.com> Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Andy Whitcroft <apw@shadowen.org> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17mm/sparse.c: check the return value of sparse_index_alloc()WANG Cong
Since sparse_index_alloc() can return NULL on memory allocation failure, we must deal with the failure condition when calling it. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17sparsemem: make SPARSEMEM_VMEMMAP selectableGeoff Levand
SPARSEMEM_VMEMMAP needs to be a selectable config option to support building the kernel both with and without sparsemem vmemmap support. This selection is desirable for platforms which could be configured one way for platform specific builds and the other for multi-platform builds. Signed-off-by: Miguel Botón <mboton@gmail.com> Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-10hugetlb: handle write-protection faults in follow_hugetlb_pageAdam Litke
The follow_hugetlb_page() fix I posted (merged as git commit 5b23dbe8173c212d6a326e35347b038705603d39) missed one case. If the pte is present, but not writable and write access is requested by the caller to get_user_pages(), the code will do the wrong thing. Rather than calling hugetlb_fault to make the pte writable, it notes the presence of the pte and continues. This simple one-liner makes sure we also fault on the pte for this case. Please apply. Signed-off-by: Adam Litke <agl@us.ibm.com> Acked-by: Dave Kleikamp <shaggy@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-09Avoid double memclear() in SLOB/SLUBLinus Torvalds
Both slob and slub react to __GFP_ZERO by clearing the allocation, which means that passing the GFP_ZERO bit down to the page allocator is just wasteful and pointless. Acked-by: Matt Mackall <mpm@selenic.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6: VM/Security: add security hook to do_brk Security: round mmap hint address above mmap_min_addr security: protect from stack expantion into low vm addresses Security: allow capable check to permit mmap or low vm space SELinux: detect dead booleans SELinux: do not clear f_op when removing entries
2007-12-05VM/Security: add security hook to do_brkEric Paris
Given a specifically crafted binary do_brk() can be used to get low pages available in userspace virtual memory and can thus be used to circumvent the mmap_min_addr low memory protection. Add security checks in do_brk(). Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Alan Cox <alan@redhat.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-05SLUB's ksize() fails for size > 2048Vegard Nossum
I can't pass memory allocated by kmalloc() to ksize() if it is allocated by SLUB allocator and size is larger than (I guess) PAGE_SIZE / 2. The error of ksize() seems to be that it does not check if the allocation was made by SLUB or the page allocator. Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Christoph Lameter <clameter@sgi.com>, Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-05mm: fix XIP file writesNick Piggin
Writing to XIP files at a non-page-aligned offset results in data corruption because the writes were always sent to the start of the page. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-05Add EXPORT_SYMBOL(ksize);Tetsuo Handa
mm/slub.c exports ksize(), but mm/slob.c and mm/slab.c don't. It's used by binfmt_flat, which can be built as a module. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Christoph Lameter <clameter@sgi.com> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-05mm/backing-dev.c: fix percpu_counter_destroy call bug in bdi_initDenis Cheng
this call should use the array index j, not i. But with this approach, just one int i is enough, int j is not needed. Signed-off-by: Denis Cheng <crquan@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-06VM/Security: add security hook to do_brkEric Paris
Given a specifically crafted binary do_brk() can be used to get low pages available in userspace virtually memory and can thus be used to circumvent the mmap_min_addr low memory protection. Add security checks in do_brk(). Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2007-12-06Security: round mmap hint address above mmap_min_addrEric Paris
If mmap_min_addr is set and a process attempts to mmap (not fixed) with a non-null hint address less than mmap_min_addr the mapping will fail the security checks. Since this is just a hint address this patch will round such a hint address above mmap_min_addr. gcj was found to try to be very frugal with vm usage and give hint addresses in the 8k-32k range. Without this patch all such programs failed and with the patch they happily get a higher address. This patch is wrappad in CONFIG_SECURITY since mmap_min_addr doesn't exist without it and there would be no security check possible no matter what. So we should not bother compiling in this rounding if it is just a waste of time. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2007-12-06security: protect from stack expantion into low vm addressesEric Paris
Add security checks to make sure we are not attempting to expand the stack into memory protected by mmap_min_addr Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2007-11-30Fix kmem_cache_free performance regression in slabMatthew Wilcox
The database performance group have found that half the cycles spent in kmem_cache_free are spent in this one call to BUG_ON. Moving it into the CONFIG_SLAB_DEBUG-only function cache_free_debugcheck() is a performance win of almost 0.5% on their particular benchmark. The call was added as part of commit ddc2e812d592457747c4367fb73edcaa8e1e49ff with the comment that "overhead should be minimal". It may have been minimal at the time, but it isn't now. [ Quoth Pekka Enberg: "I don't think the BUG_ON per se caused the performance regression but rather the virt_to_head_page() changes to virt_to_cache() that were added later." ] Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Acked-by: Pekka J Enberg <penberg@cs.helsinki.fi> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29memory hotplug fix: fix section mismatch in vmammap_allock_block()KAMEZAWA Hiroyuki
Fixes section mismatch below. WARNING: vmlinux.o(.text+0x946b5): Section mismatch: reference to .init.text:' __alloc_bootmem_node (between 'vmemmap_alloc_block' and 'vmemmap_pgd_populate') Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29Fix boot problem with iSeries lacking hugepage supportMel Gorman
Ordinarily the size of a pageblock is determined at compile-time based on the hugepage size. On PPC64, the hugepage size is determined at runtime based on what is supported by the machine. With legacy machines such as iSeries that do not support hugepages, HPAGE_SHIFT is 0. This results in pageblock_order being set to -PAGE_SHIFT and a crash results shortly afterwards. This patch adds a function to select a sensible value for pageblock order by default when HUGETLB_PAGE_SIZE_VARIABLE is set. It checks that HPAGE_SHIFT is a sensible value before using the hugepage size; if it is not MAX_ORDER-1 is used. This is a fix for 2.6.24. Credit goes to Stephen Rothwell for identifying the bug and testing candidate patches. Additional credit goes to Andy Whitcroft for spotting a problem with respects to IA-64 before releasing. Additional credit to David Gibson for testing with the libhugetlbfs test suite. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28prep_zero_page: remove bogus BUG_ONHugh Dickins
2.6.11 gave __GFP_ZERO's prep_zero_page a bogus "highmem may have to wait" assertion. Presumably added under the misconception that clear_highpage uses nonatomic kmap; but then and now it uses kmap_atomic, so no problem. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28tmpfs: restore missing clear_highpageHugh Dickins
tmpfs was misconverted to __GFP_ZERO in 2.6.11. There's an unusual case in which shmem_getpage receives the page from its caller instead of allocating. We must cover this case by clear_highpage before SetPageUptodate, as before. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>