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2015-04-14x86, mm/ASLR: Fix stack randomization on 64-bit systemsHector Marco-Gisbert1-3/+3
commit 4e7c22d447bb6d7e37bfe39ff658486ae78e8d77 upstream. The issue is that the stack for processes is not properly randomized on 64 bit architectures due to an integer overflow. The affected function is randomize_stack_top() in file "fs/binfmt_elf.c": static unsigned long randomize_stack_top(unsigned long stack_top) { unsigned int random_variable = 0; if ((current->flags & PF_RANDOMIZE) && !(current->personality & ADDR_NO_RANDOMIZE)) { random_variable = get_random_int() & STACK_RND_MASK; random_variable <<= PAGE_SHIFT; } return PAGE_ALIGN(stack_top) + random_variable; return PAGE_ALIGN(stack_top) - random_variable; } Note that, it declares the "random_variable" variable as "unsigned int". Since the result of the shifting operation between STACK_RND_MASK (which is 0x3fffff on x86_64, 22 bits) and PAGE_SHIFT (which is 12 on x86_64): random_variable <<= PAGE_SHIFT; then the two leftmost bits are dropped when storing the result in the "random_variable". This variable shall be at least 34 bits long to hold the (22+12) result. These two dropped bits have an impact on the entropy of process stack. Concretely, the total stack entropy is reduced by four: from 2^28 to 2^30 (One fourth of expected entropy). This patch restores back the entropy by correcting the types involved in the operations in the functions randomize_stack_top() and stack_maxrandom_size(). The successful fix can be tested with: $ for i in `seq 1 10`; do cat /proc/self/maps | grep stack; done 7ffeda566000-7ffeda587000 rw-p 00000000 00:00 0 [stack] 7fff5a332000-7fff5a353000 rw-p 00000000 00:00 0 [stack] 7ffcdb7a1000-7ffcdb7c2000 rw-p 00000000 00:00 0 [stack] 7ffd5e2c4000-7ffd5e2e5000 rw-p 00000000 00:00 0 [stack] ... Once corrected, the leading bytes should be between 7ffc and 7fff, rather than always being 7fff. Signed-off-by: Hector Marco-Gisbert <hecmargi@upv.es> Signed-off-by: Ismael Ripoll <iripoll@upv.es> [ Rebased, fixed 80 char bugs, cleaned up commit message, added test example and CVE ] Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Fixes: CVE-2015-1593 Link: http://lkml.kernel.org/r/20150214173350.GA18393@www.outflux.net Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Zefan Li <lizefan@huawei.com>
2015-04-14vm: add VM_FAULT_SIGSEGV handling supportLinus Torvalds1-0/+2
commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream. The core VM already knows about VM_FAULT_SIGBUS, but cannot return a "you should SIGSEGV" error, because the SIGSEGV case was generally handled by the caller - usually the architecture fault handler. That results in lots of duplication - all the architecture fault handlers end up doing very similar "look up vma, check permissions, do retries etc" - but it generally works. However, there are cases where the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV. In particular, when accessing the stack guard page, libsigsegv expects a SIGSEGV. And it usually got one, because the stack growth is handled by that duplicated architecture fault handler. However, when the generic VM layer started propagating the error return from the stack expansion in commit fee7e49d4514 ("mm: propagate error from stack expansion even for guard page"), that now exposed the existing VM_FAULT_SIGBUS result to user space. And user space really expected SIGSEGV, not SIGBUS. To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those duplicate architecture fault handlers about it. They all already have the code to handle SIGSEGV, so it's about just tying that new return value to the existing code, but it's all a bit annoying. This is the mindless minimal patch to do this. A more extensive patch would be to try to gather up the mostly shared fault handling logic into one generic helper routine, and long-term we really should do that cleanup. Just from this patch, you can generally see that most architectures just copied (directly or indirectly) the old x86 way of doing things, but in the meantime that original x86 model has been improved to hold the VM semaphore for shorter times etc and to handle VM_FAULT_RETRY and other "newer" things, so it would be a good idea to bring all those improvements to the generic case and teach other architectures about them too. Reported-and-tested-by: Takashi Iwai <tiwai@suse.de> Tested-by: Jan Engelhardt <jengelh@inai.de> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots" Cc: linux-arch@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: - Adjust filenames, context - Drop arc, metag, nios2 and lustre changes - For sh, patch both 32-bit and 64-bit implementations to use goto bad_area - For s390, pass int_code and trans_exc_code as arguments to do_no_context() and do_sigsegv()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> [lizf: Backported to 3.4: - adjust context in arch/power/mm/fault.c - apply the original change in upstream commit for s390] Signed-off-by: Zefan Li <lizefan@huawei.com>
2014-08-07x86-64, espfix: Don't leak bits 31:16 of %esp returning to 16-bit stackH. Peter Anvin1-11/+28
commit 3891a04aafd668686239349ea58f3314ea2af86b upstream. The IRET instruction, when returning to a 16-bit segment, only restores the bottom 16 bits of the user space stack pointer. This causes some 16-bit software to break, but it also leaks kernel state to user space. We have a software workaround for that ("espfix") for the 32-bit kernel, but it relies on a nonzero stack segment base which is not available in 64-bit mode. In checkin: b3b42ac2cbae x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels we "solved" this by forbidding 16-bit segments on 64-bit kernels, with the logic that 16-bit support is crippled on 64-bit kernels anyway (no V86 support), but it turns out that people are doing stuff like running old Win16 binaries under Wine and expect it to work. This works around this by creating percpu "ministacks", each of which is mapped 2^16 times 64K apart. When we detect that the return SS is on the LDT, we copy the IRET frame to the ministack and use the relevant alias to return to userspace. The ministacks are mapped readonly, so if IRET faults we promote #GP to #DF which is an IST vector and thus has its own stack; we then do the fixup in the #DF handler. (Making #GP an IST exception would make the msr_safe functions unsafe in NMI/MC context, and quite possibly have other effects.) Special thanks to: - Andy Lutomirski, for the suggestion of using very small stack slots and copy (as opposed to map) the IRET frame there, and for the suggestion to mark them readonly and let the fault promote to #DF. - Konrad Wilk for paravirt fixup and testing. - Borislav Petkov for testing help and useful comments. Reported-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Andrew Lutomriski <amluto@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Dirk Hohndel <dirk@hohndel.org> Cc: Arjan van de Ven <arjan.van.de.ven@intel.com> Cc: comex <comexk@gmail.com> Cc: Alexander van Heukelum <heukelum@fastmail.fm> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-18x86, ioremap: Speed up check for RAM pagesRoland Dreier1-7/+19
commit c81c8a1eeede61e92a15103748c23d100880cc8a upstream. In __ioremap_caller() (the guts of ioremap), we loop over the range of pfns being remapped and checks each one individually with page_is_ram(). For large ioremaps, this can be very slow. For example, we have a device with a 256 GiB PCI BAR, and ioremapping this BAR can take 20+ seconds -- sometimes long enough to trigger the soft lockup detector! Internally, page_is_ram() calls walk_system_ram_range() on a single page. Instead, we can make a single call to walk_system_ram_range() from __ioremap_caller(), and do our further checks only for any RAM pages that we find. For the common case of MMIO, this saves an enormous amount of work, since the range being ioremapped doesn't intersect system RAM at all. With this change, ioremap on our 256 GiB BAR takes less than 1 second. Signed-off-by: Roland Dreier <roland@purestorage.com> Link: http://lkml.kernel.org/r/1399054721-1331-1-git-send-email-roland@kernel.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-08x86 get_unmapped_area: Access mmap_legacy_base through mm_struct memberRadu Caragea1-2/+4
commit 41aacc1eea645c99edbe8fbcf78a97dc9b862adc upstream. This is the updated version of df54d6fa5427 ("x86 get_unmapped_area(): use proper mmap base for bottom-up direction") that only randomizes the mmap base address once. Signed-off-by: Radu Caragea <sinaelgl@gmail.com> Reported-and-tested-by: Jeff Shorey <shoreyjeff@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michel Lespinasse <walken@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Adrian Sendroiu <molecula2788@gmail.com> Cc: Greg KH <greg@kroah.com> Cc: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Rui Xiang <rui.xiang@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-12x86/mm: account for PGDIR_SIZE alignmentJerry Hoemann1-0/+5
Patch for -stable. Function find_early_table_space removed upstream. Fixes panic in alloc_low_page due to pgt_buf overflow during init_memory_mapping. find_early_table_space sizes pgt_buf based upon the size of the memory being mapped, but it does not take into account the alignment of the memory. When the region being mapped spans a 512GB (PGDIR_SIZE) alignment, a panic from alloc_low_pages occurs. kernel_physical_mapping_init takes into account PGDIR_SIZE alignment. This causes an extra call to alloc_low_page to be made. This extra call isn't accounted for by find_early_table_space and causes a kernel panic. Change is to take into account PGDIR_SIZE alignment in find_early_table_space. Signed-off-by: Jerry Hoemann <jerry.hoemann@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-17x86, mm, paravirt: Fix vmalloc_fault oops during lazy MMU updatesSamu Kallio1-2/+4
commit 1160c2779b826c6f5c08e5cc542de58fd1f667d5 upstream. In paravirtualized x86_64 kernels, vmalloc_fault may cause an oops when lazy MMU updates are enabled, because set_pgd effects are being deferred. One instance of this problem is during process mm cleanup with memory cgroups enabled. The chain of events is as follows: - zap_pte_range enables lazy MMU updates - zap_pte_range eventually calls mem_cgroup_charge_statistics, which accesses the vmalloc'd mem_cgroup per-cpu stat area - vmalloc_fault is triggered which tries to sync the corresponding PGD entry with set_pgd, but the update is deferred - vmalloc_fault oopses due to a mismatch in the PUD entries The OOPs usually looks as so: ------------[ cut here ]------------ kernel BUG at arch/x86/mm/fault.c:396! invalid opcode: 0000 [#1] SMP .. snip .. CPU 1 Pid: 10866, comm: httpd Not tainted 3.6.10-4.fc18.x86_64 #1 RIP: e030:[<ffffffff816271bf>] [<ffffffff816271bf>] vmalloc_fault+0x11f/0x208 .. snip .. Call Trace: [<ffffffff81627759>] do_page_fault+0x399/0x4b0 [<ffffffff81004f4c>] ? xen_mc_extend_args+0xec/0x110 [<ffffffff81624065>] page_fault+0x25/0x30 [<ffffffff81184d03>] ? mem_cgroup_charge_statistics.isra.13+0x13/0x50 [<ffffffff81186f78>] __mem_cgroup_uncharge_common+0xd8/0x350 [<ffffffff8118aac7>] mem_cgroup_uncharge_page+0x57/0x60 [<ffffffff8115fbc0>] page_remove_rmap+0xe0/0x150 [<ffffffff8115311a>] ? vm_normal_page+0x1a/0x80 [<ffffffff81153e61>] unmap_single_vma+0x531/0x870 [<ffffffff81154962>] unmap_vmas+0x52/0xa0 [<ffffffff81007442>] ? pte_mfn_to_pfn+0x72/0x100 [<ffffffff8115c8f8>] exit_mmap+0x98/0x170 [<ffffffff810050d9>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81059ce3>] mmput+0x83/0xf0 [<ffffffff810624c4>] exit_mm+0x104/0x130 [<ffffffff8106264a>] do_exit+0x15a/0x8c0 [<ffffffff810630ff>] do_group_exit+0x3f/0xa0 [<ffffffff81063177>] sys_exit_group+0x17/0x20 [<ffffffff8162bae9>] system_call_fastpath+0x16/0x1b Calling arch_flush_lazy_mmu_mode immediately after set_pgd makes the changes visible to the consistency checks. RedHat-Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=914737 Tested-by: Josh Boyer <jwboyer@redhat.com> Reported-and-Tested-by: Krishna Raman <kraman@redhat.com> Signed-off-by: Samu Kallio <samu.kallio@aberdeencloud.com> Link: http://lkml.kernel.org/r/1364045796-10720-1-git-send-email-konrad.wilk@oracle.com Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-28x86-32, mm: Remove reference to alloc_remap()H. Peter Anvin1-18/+11
commit 07f4207a305c834f528d08428df4531744e25678 upstream. We have removed the remap allocator for x86-32, and x86-64 never had it (and doesn't need it). Remove residual reference to it. Reported-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/CAE9FiQVn6_QZi3fNQ-JHYiR-7jeDJ5hT0SyT_%2BzVvfOj=PzF3w@mail.gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-28x86-32, mm: Rip out x86_32 NUMA remapping codeDave Hansen3-170/+0
commit f03574f2d5b2d6229dcdf2d322848065f72953c7 upstream. This code was an optimization for 32-bit NUMA systems. It has probably been the cause of a number of subtle bugs over the years, although the conditions to excite them would have been hard to trigger. Essentially, we remap part of the kernel linear mapping area, and then sometimes part of that area gets freed back in to the bootmem allocator. If those pages get used by kernel data structures (say mem_map[] or a dentry), there's no big deal. But, if anyone ever tried to use the linear mapping for these pages _and_ cared about their physical address, bad things happen. For instance, say you passed __GFP_ZERO to the page allocator and then happened to get handed one of these pages, it zero the remapped page, but it would make a pte to the _old_ page. There are probably a hundred other ways that it could screw with things. We don't need to hang on to performance optimizations for these old boxes any more. All my 32-bit NUMA systems are long dead and buried, and I probably had access to more than most people. This code is causing real things to break today: https://lkml.org/lkml/2013/1/9/376 I looked in to actually fixing this, but it requires surgery to way too much brittle code, as well as stuff like per_cpu_ptr_to_phys(). [ hpa: Cc: this for -stable, since it is a memory corruption issue. However, an alternative is to simply mark NUMA as depends BROKEN rather than EXPERIMENTAL in the X86_32 subclause... ] Link: http://lkml.kernel.org/r/20130131005616.1C79F411@kernel.stglabs.ibm.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-17x86/mm: Check if PUD is large when validating a kernel addressMel Gorman1-0/+3
commit 0ee364eb316348ddf3e0dfcd986f5f13f528f821 upstream. A user reported the following oops when a backup process reads /proc/kcore: BUG: unable to handle kernel paging request at ffffbb00ff33b000 IP: [<ffffffff8103157e>] kern_addr_valid+0xbe/0x110 [...] Call Trace: [<ffffffff811b8aaa>] read_kcore+0x17a/0x370 [<ffffffff811ad847>] proc_reg_read+0x77/0xc0 [<ffffffff81151687>] vfs_read+0xc7/0x130 [<ffffffff811517f3>] sys_read+0x53/0xa0 [<ffffffff81449692>] system_call_fastpath+0x16/0x1b Investigation determined that the bug triggered when reading system RAM at the 4G mark. On this system, that was the first address using 1G pages for the virt->phys direct mapping so the PUD is pointing to a physical address, not a PMD page. The problem is that the page table walker in kern_addr_valid() is not checking pud_large() and treats the physical address as if it was a PMD. If it happens to look like pmd_none then it'll silently fail, probably returning zeros instead of real data. If the data happens to look like a present PMD though, it will be walked resulting in the oops above. This patch adds the necessary pud_large() check. Unfortunately the problem was not readily reproducible and now they are running the backup program without accessing /proc/kcore so the patch has not been validated but I think it makes sense. Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.coM> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20130211145236.GX21389@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-17x86: Do not leak kernel page mapping locationsKees Cook1-3/+5
commit e575a86fdc50d013bf3ad3aa81d9100e8e6cc60d upstream. Without this patch, it is trivial to determine kernel page mappings by examining the error code reported to dmesg[1]. Instead, declare the entire kernel memory space as a violation of a present page. Additionally, since show_unhandled_signals is enabled by default, switch branch hinting to the more realistic expectation, and unobfuscate the setting of the PF_PROT bit to improve readability. [1] http://vulnfactory.org/blog/2013/02/06/a-linux-memory-trick/ Reported-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Suggested-by: Brad Spengler <spender@grsecurity.net> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20130207174413.GA12485@www.outflux.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31x86, mm: Undo incorrect revert in arch/x86/mm/init.cYinghai Lu1-4/+0
commit f82f64dd9f485e13f29f369772d4a0e868e5633a upstream. Commit 844ab6f9 x86, mm: Find_early_table_space based on ranges that are actually being mapped added back some lines back wrongly that has been removed in commit 7b16bbf97 Revert "x86/mm: Fix the size calculation of mapping tables" remove them again. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/CAE9FiQW_vuaYQbmagVnxT2DGsYc=9tNeAbdBq53sYkitPOwxSQ@mail.gmail.com Acked-by: Jacob Shin <jacob.shin@amd.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31x86, mm: Find_early_table_space based on ranges that are actually being mappedJacob Shin1-30/+43
commit 844ab6f993b1d32eb40512503d35ff6ad0c57030 upstream. Current logic finds enough space for direct mapping page tables from 0 to end. Instead, we only need to find enough space to cover mr[0].start to mr[nr_range].end -- the range that is actually being mapped by init_memory_mapping() This is needed after 1bbbbe779aabe1f0768c2bf8f8c0a5583679b54a, to address the panic reported here: https://lkml.org/lkml/2012/10/20/160 https://lkml.org/lkml/2012/10/21/157 Signed-off-by: Jacob Shin <jacob.shin@amd.com> Link: http://lkml.kernel.org/r/20121024195311.GB11779@jshin-Toonie Tested-by: Tom Rini <trini@ti.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-14mm: hugetlbfs: correctly populate shared pmdMichal Hocko1-5/+16
commit eb48c071464757414538c68a6033c8f8c15196f8 upstream. Each page mapped in a process's address space must be correctly accounted for in _mapcount. Normally the rules for this are straightforward but hugetlbfs page table sharing is different. The page table pages at the PMD level are reference counted while the mapcount remains the same. If this accounting is wrong, it causes bugs like this one reported by Larry Woodman: kernel BUG at mm/filemap.c:135! invalid opcode: 0000 [#1] SMP CPU 22 Modules linked in: bridge stp llc sunrpc binfmt_misc dcdbas microcode pcspkr acpi_pad acpi] Pid: 18001, comm: mpitest Tainted: G W 3.3.0+ #4 Dell Inc. PowerEdge R620/07NDJ2 RIP: 0010:[<ffffffff8112cfed>] [<ffffffff8112cfed>] __delete_from_page_cache+0x15d/0x170 Process mpitest (pid: 18001, threadinfo ffff880428972000, task ffff880428b5cc20) Call Trace: delete_from_page_cache+0x40/0x80 truncate_hugepages+0x115/0x1f0 hugetlbfs_evict_inode+0x18/0x30 evict+0x9f/0x1b0 iput_final+0xe3/0x1e0 iput+0x3e/0x50 d_kill+0xf8/0x110 dput+0xe2/0x1b0 __fput+0x162/0x240 During fork(), copy_hugetlb_page_range() detects if huge_pte_alloc() shared page tables with the check dst_pte == src_pte. The logic is if the PMD page is the same, they must be shared. This assumes that the sharing is between the parent and child. However, if the sharing is with a different process entirely then this check fails as in this diagram: parent | ------------>pmd src_pte----------> data page ^ other--------->pmd--------------------| ^ child-----------| dst_pte For this situation to occur, it must be possible for Parent and Other to have faulted and failed to share page tables with each other. This is possible due to the following style of race. PROC A PROC B copy_hugetlb_page_range copy_hugetlb_page_range src_pte == huge_pte_offset src_pte == huge_pte_offset !src_pte so no sharing !src_pte so no sharing (time passes) hugetlb_fault hugetlb_fault huge_pte_alloc huge_pte_alloc huge_pmd_share huge_pmd_share LOCK(i_mmap_mutex) find nothing, no sharing UNLOCK(i_mmap_mutex) LOCK(i_mmap_mutex) find nothing, no sharing UNLOCK(i_mmap_mutex) pmd_alloc pmd_alloc LOCK(instantiation_mutex) fault UNLOCK(instantiation_mutex) LOCK(instantiation_mutex) fault UNLOCK(instantiation_mutex) These two processes are not poing to the same data page but are not sharing page tables because the opportunity was missed. When either process later forks, the src_pte == dst pte is potentially insufficient. As the check falls through, the wrong PTE information is copied in (harmless but wrong) and the mapcount is bumped for a page mapped by a shared page table leading to the BUG_ON. This patch addresses the issue by moving pmd_alloc into huge_pmd_share which guarantees that the shared pud is populated in the same critical section as pmd. This also means that huge_pte_offset test in huge_pmd_share is serialized correctly now which in turn means that the success of the sharing will be higher as the racing tasks see the pud and pmd populated together. Race identified and changelog written mostly by Mel Gorman. {akpm@linux-foundation.org: attempt to make the huge_pmd_share() comment comprehensible, clean up coding style] Reported-by: Larry Woodman <lwoodman@redhat.com> Tested-by: Larry Woodman <lwoodman@redhat.com> Reviewed-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Michal Hocko <mhocko@suse.cz> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Ken Chen <kenchen@google.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Hillf Danton <dhillf@gmail.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@linuxfoundation.org>
2012-03-30Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds1-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Peter Anvin: "The biggest textual change is the cleanup to use symbolic constants for x86 trap values. The only *functional* change and the reason for the x86/x32 dependency is the move of is_ia32_task() into <asm/thread_info.h> so that it can be used in other code that needs to understand if a system call comes from the compat entry point (and therefore uses i386 system call numbers) or not. One intended user for that is the BPF system call filter. Moving it out of <asm/compat.h> means we can define it unconditionally, returning always true on i386." * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Move is_ia32_task to asm/thread_info.h from asm/compat.h x86: Rename trap_no to trap_nr in thread_struct x86: Use enum instead of literals for trap values
2012-03-30Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 updates from Ingo Molnar. This touches some non-x86 files due to the sanitized INLINE_SPIN_UNLOCK config usage. Fixed up trivial conflicts due to just header include changes (removing headers due to cpu_idle() merge clashing with the <asm/system.h> split). * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/amd: Be more verbose about LVT offset assignments x86, tls: Off by one limit check x86/ioapic: Add io_apic_ops driver layer to allow interception x86/olpc: Add debugfs interface for EC commands x86: Merge the x86_32 and x86_64 cpu_idle() functions x86/kconfig: Remove CONFIG_TR=y from the defconfigs x86: Stop recursive fault in print_context_stack after stack overflow x86/io_apic: Move and reenable irq only when CONFIG_GENERIC_PENDING_IRQ=y x86/apic: Add separate apic_id_valid() functions for selected apic drivers locking/kconfig: Simplify INLINE_SPIN_UNLOCK usage x86/kconfig: Update defconfigs x86: Fix excessive MSR print out when show_msr is not specified
2012-03-29Merge tag 'split-asm_system_h-for-linus-20120328' of ↵Linus Torvalds4-4/+0
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system Pull "Disintegrate and delete asm/system.h" from David Howells: "Here are a bunch of patches to disintegrate asm/system.h into a set of separate bits to relieve the problem of circular inclusion dependencies. I've built all the working defconfigs from all the arches that I can and made sure that they don't break. The reason for these patches is that I recently encountered a circular dependency problem that came about when I produced some patches to optimise get_order() by rewriting it to use ilog2(). This uses bitops - and on the SH arch asm/bitops.h drags in asm-generic/get_order.h by a circuituous route involving asm/system.h. The main difficulty seems to be asm/system.h. It holds a number of low level bits with no/few dependencies that are commonly used (eg. memory barriers) and a number of bits with more dependencies that aren't used in many places (eg. switch_to()). These patches break asm/system.h up into the following core pieces: (1) asm/barrier.h Move memory barriers here. This already done for MIPS and Alpha. (2) asm/switch_to.h Move switch_to() and related stuff here. (3) asm/exec.h Move arch_align_stack() here. Other process execution related bits could perhaps go here from asm/processor.h. (4) asm/cmpxchg.h Move xchg() and cmpxchg() here as they're full word atomic ops and frequently used by atomic_xchg() and atomic_cmpxchg(). (5) asm/bug.h Move die() and related bits. (6) asm/auxvec.h Move AT_VECTOR_SIZE_ARCH here. Other arch headers are created as needed on a per-arch basis." Fixed up some conflicts from other header file cleanups and moving code around that has happened in the meantime, so David's testing is somewhat weakened by that. We'll find out anything that got broken and fix it.. * tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits) Delete all instances of asm/system.h Remove all #inclusions of asm/system.h Add #includes needed to permit the removal of asm/system.h Move all declarations of free_initmem() to linux/mm.h Disintegrate asm/system.h for OpenRISC Split arch_align_stack() out from asm-generic/system.h Split the switch_to() wrapper out of asm-generic/system.h Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h Create asm-generic/barrier.h Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h Disintegrate asm/system.h for Xtensa Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt] Disintegrate asm/system.h for Tile Disintegrate asm/system.h for Sparc Disintegrate asm/system.h for SH Disintegrate asm/system.h for Score Disintegrate asm/system.h for S390 Disintegrate asm/system.h for PowerPC Disintegrate asm/system.h for PA-RISC Disintegrate asm/system.h for MN10300 ...
2012-03-28Disintegrate asm/system.h for X86David Howells4-4/+0
Disintegrate asm/system.h for X86. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> cc: x86@kernel.org
2012-03-24Merge tag 'bug-for-3.4' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull <linux/bug.h> cleanup from Paul Gortmaker: "The changes shown here are to unify linux's BUG support under the one <linux/bug.h> file. Due to historical reasons, we have some BUG code in bug.h and some in kernel.h -- i.e. the support for BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h, but old code in kernel.h wasn't moved to bug.h at that time. As a band-aid, kernel.h was including <asm/bug.h> to pseudo link them. This has caused confusion[1] and general yuck/WTF[2] reactions. Here is an example that violates the principle of least surprise: CC lib/string.o lib/string.c: In function 'strlcat': lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON' make[2]: *** [lib/string.o] Error 1 $ $ grep linux/bug.h lib/string.c #include <linux/bug.h> $ We've included <linux/bug.h> for the BUG infrastructure and yet we still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh - very confusing for someone who is new to kernel development. With the above in mind, the goals of this changeset are: 1) find and fix any include/*.h files that were relying on the implicit presence of BUG code. 2) find and fix any C files that were consuming kernel.h and hence relying on implicitly getting some/all BUG code. 3) Move the BUG related code living in kernel.h to <linux/bug.h> 4) remove the asm/bug.h from kernel.h to finally break the chain. During development, the order was more like 3-4, build-test, 1-2. But to ensure that git history for bisect doesn't get needless build failures introduced, the commits have been reorderd to fix the problem areas in advance. [1] https://lkml.org/lkml/2012/1/3/90 [2] https://lkml.org/lkml/2012/1/17/414" Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul and linux-next. * tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: kernel.h: doesn't explicitly use bug.h, so don't include it. bug: consolidate BUILD_BUG_ON with other bug code BUG: headers with BUG/BUG_ON etc. need linux/bug.h bug.h: add include of it to various implicit C users lib: fix implicit users of kernel.h for TAINT_WARN spinlock: macroize assert_spin_locked to avoid bug.h dependency x86: relocate get/set debugreg fcns to include/asm/debugreg.
2012-03-23x86/apic: Add separate apic_id_valid() functions for selected apic driversSteffen Persvold1-1/+1
As suggested by Suresh Siddha and Yinghai Lu: For x2apic pre-enabled systems, apic driver is set already early through early_acpi_boot_init()/early_acpi_process_madt()/ acpi_parse_madt()/default_acpi_madt_oem_check() path so that apic_id_valid() checking will be sufficient during MADT and SRAT parsing. For non-x2apic pre-enabled systems, all apic ids should be less than 255. This allows us to substitute the checks in arch/x86/kernel/acpi/boot.c::acpi_parse_x2apic() and arch/x86/mm/srat.c::acpi_numa_x2apic_affinity_init() with apic->apic_id_valid(). In addition we can avoid feigning the x2apic cpu feature in the NumaChip apic code. The following apic drivers have separate apic_id_valid() functions which will accept x2apic type IDs : x2apic_phys x2apic_cluster x2apic_uv_x apic_numachip Signed-off-by: Steffen Persvold <sp@numascale.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Daniel J Blueman <daniel@numascale-asia.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jack Steiner <steiner@sgi.com> Link: http://lkml.kernel.org/r/1331925935-13372-1-git-send-email-sp@numascale.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-03-22Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 "urgent" leftovers from Ingo Molnar: "Pending x86/urgent bits that were not high prio enough to warrant -rc-less v3.3-final inclusion." * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, efi: Fix pointer math issue in handle_ramdisks() x86/ioapic: Add register level checks to detect bogus io-apic entries x86, mce: Fix rcu splat in drain_mce_log_buffer() x86, memblock: Move mem_hole_size() to .init
2012-03-22numa_emulation: fix cpumask_of_node()Andrea Arcangeli1-1/+1
Without this fix the cpumask_of_node() for a fake=numa=2 is: cpumask 0 ff cpumask 1 ff with the fix it's correct and it's set to: cpumask 0 55 cpumask 1 aa Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Johannes Weiner <jweiner@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22hugetlb: remove prev_vma from hugetlb_get_unmapped_area_topdown()Xiao Guangrong1-13/+5
After looking up the vma which covers or follows the cached search address, the following condition is always true: !prev_vma || (addr >= prev_vma->vm_end) so we can stop checking the previous VMA altogether. Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22hugetlb: try to search again if it is really neededXiao Guangrong1-4/+6
Search again only if some holes may be skipped in the first pass. [akpm@linux-foundation.org: clean up crazy compound definition] Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Hillf Danton <dhillf@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-20highmem: kill all __kmap_atomic()Cong Wang1-2/+2
[swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename] Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-13x86: Rename trap_no to trap_nr in thread_structSrikar Dronamraju1-5/+5
There are precedences of trap number being referred to as trap_nr. However thread struct refers trap number as trap_no. Change it to trap_nr. Also use enum instead of left-over literals for trap values. This is pure cleanup, no functional change intended. Suggested-by: Ingo Molnar <mingo@eltu.hu> Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com> Cc: Linux-mm <linux-mm@kvack.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120312092555.5379.942.sendpatchset@srdronam.in.ibm.com [ Fixed the math-emu build ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-07x86: fix typo in recent find_vma_prev purgeLinus Torvalds1-1/+1
It turns out that test-compiling this file on x86-64 doesn't really help, because much of it is x86-32-specific. And so I hadn't noticed the slightly over-eager removal of the 'r' from 'addr' variable despite thinking I had tested it. Signed-off-by: Linus "oopsie" Torvalds <torvalds@linux-foundation.org>
2012-03-07vm: avoid using find_vma_prev() unnecessarilyLinus Torvalds1-1/+3
Several users of "find_vma_prev()" were not in fact interested in the previous vma if there was no primary vma to be found either. And in those cases, we're much better off just using the regular "find_vma()", and then "prev" can be looked up by just checking vma->vm_prev. The find_vma_prev() semantics are fairly subtle (see Mikulas' recent commit 83cd904d271b: "mm: fix find_vma_prev"), and the whole "return prev by reference" means that it generates worse code too. Thus this "let's avoid using this inconvenient and clearly too subtle interface when we don't really have to" patch. Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-04x86, memblock: Move mem_hole_size() to .initJiri Kosina1-1/+1
mem_hole_size() is being called only from __init-marked functions, and as such should be moved to .init section as well. Fixes this warning: WARNING: vmlinux.o(.text+0x35511): Section mismatch in reference from the function mem_hole_size() to the function .init.text:absent_pages_in_range() Signed-off-by: Jiri Kosina <jkosina@suse.cz> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1202281614450.31150@pobox.suse.cz Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-03-01bug.h: add include of it to various implicit C usersPaul Gortmaker1-0/+1
With bug.h currently living right in linux/kernel.h there are files that use BUG_ON and friends but are not including the header explicitly. Fix them up so we can remove the presence in kernel.h file. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-02Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', ↵Linus Torvalds1-2/+2
'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: bugs, x86: Fix printk levels for panic, softlockups and stack dumps * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf top: Fix number of samples displayed perf tools: Fix strlen() bug in perf_event__synthesize_event_type() perf tools: Fix broken build by defining _GNU_SOURCE in Makefile x86/dumpstack: Remove unneeded check in dump_trace() perf: Fix broken interrupt rate throttling * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW sched: Fix ancient race in do_exit() sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug sched/s390: Fix compile error in sched/core.c sched: Fix rq->nr_uninterruptible update race * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/reboot: Remove VersaLogic Menlow reboot quirk x86/reboot: Skip DMI checks if reboot set by user x86: Properly parenthesize cmpxchg() macro arguments
2012-01-27bugs, x86: Fix printk levels for panic, softlockups and stack dumpsPrarit Bhargava1-2/+2
rsyslog will display KERN_EMERG messages on a connected terminal. However, these messages are useless/undecipherable for a general user. For example, after a softlockup we get: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Stack: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Call Trace: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Code: ff ff a8 08 75 25 31 d2 48 8d 86 38 e0 ff ff 48 89 d1 0f 01 c8 0f ae f0 48 8b 86 38 e0 ff ff a8 08 75 08 b1 01 4c 89 e0 0f 01 c9 <e8> ea 69 dd ff 4c 29 e8 48 89 c7 e8 0f bc da ff 49 89 c4 49 89 This happens because the printk levels for these messages are incorrect. Only an informational message should be displayed on a terminal. I modified the printk levels for various messages in the kernel and tested the output by using the drivers/misc/lkdtm.c kernel modules (ie, softlockups, panics, hard lockups, etc.) and confirmed that the console output was still the same and that the output to the terminals was correct. For example, in the case of a softlockup we now see the much more informative: Message from syslogd@intel-s3e37-04 at Jan 25 10:18:06 ... BUG: soft lockup - CPU4 stuck for 60s! instead of the above confusing messages. AFAICT, the messages no longer have to be KERN_EMERG. In the most important case of a panic we set console_verbose(). As for the other less severe cases the correct data is output to the console and /var/log/messages. Successfully tested by me using the drivers/misc/lkdtm.c module. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Cc: dzickus@redhat.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1327586134-11926-1-git-send-email-prarit@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-19Merge branch 'release' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux This includes initial support for the recently published ACPI 5.0 spec. In particular, support for the "hardware-reduced" bit that eliminates the dependency on legacy hardware. APEI has patches resulting from testing on real hardware. Plus other random fixes. * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (52 commits) acpi/apei/einj: Add extensions to EINJ from rev 5.0 of acpi spec intel_idle: Split up and provide per CPU initialization func ACPI processor: Remove unneeded variable passed by acpi_processor_hotadd_init V2 ACPI processor: Remove unneeded cpuidle_unregister_driver call intel idle: Make idle driver more robust intel_idle: Fix a cast to pointer from integer of different size warning in intel_idle ACPI: kernel-parameters.txt : Add intel_idle.max_cstate intel_idle: remove redundant local_irq_disable() call ACPI processor: Fix error path, also remove sysdev link ACPI: processor: fix acpi_get_cpuid for UP processor intel_idle: fix API misuse ACPI APEI: Convert atomicio routines ACPI: Export interfaces for ioremapping/iounmapping ACPI registers ACPI: Fix possible alignment issues with GAS 'address' references ACPI, ia64: Use SRAT table rev to use 8bit or 16/32bit PXM fields (ia64) ACPI, x86: Use SRAT table rev to use 8bit or 32bit PXM fields (x86/x86-64) ACPI: Store SRAT table revision ACPI, APEI, Resolve false conflict between ACPI NVS and APEI ACPI, Record ACPI NVS regions ACPI, APEI, EINJ, Refine the fix of resource conflict ...
2012-01-17ACPI, x86: Use SRAT table rev to use 8bit or 32bit PXM fields (x86/x86-64)Kurt Garloff1-0/+4
In SRAT v1, we had 8bit proximity domain (PXM) fields; SRAT v2 provides 32bits for these. The new fields were reserved before. According to the ACPI spec, the OS must disregrard reserved fields. x86/x86-64 was rather inconsistent prior to this patch; it used 8 bits for the pxm field in cpu_affinity, but 32 bits in mem_affinity. This patch makes it consistent: Either use 8 bits consistently (SRAT rev 1 or lower) or 32 bits (SRAT rev 2 or higher). cc: x86@kernel.org Signed-off-by: Kurt Garloff <kurt@garloff.de> Signed-off-by: Len Brown <len.brown@intel.com>
2012-01-15Merge tag 'for-linus' of git://github.com/rustyrussell/linuxLinus Torvalds1-2/+2
Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 * tag 'for-linus' of git://github.com/rustyrussell/linux: module_param: check that bool parameters really are bool. intelfbdrv.c: bailearly is an int module_param paride/pcd: fix bool verbose module parameter. module_param: make bool parameters really bool (drivers & misc) module_param: make bool parameters really bool (arch) module_param: make bool parameters really bool (core code) kernel/async: remove redundant declaration. printk: fix unnecessary module_param_name. lirc_parallel: fix module parameter description. module_param: avoid bool abuse, add bint for special cases. module_param: check type correctness for module_param_array modpost: use linker section to generate table. modpost: use a table rather than a giant if/else statement. modules: sysfs - export: taint, coresize, initsize kernel/params: replace DEBUGP with pr_debug module: replace DEBUGP with pr_debug module: struct module_ref should contains long fields module: Fix performance regression on modules with large symbol tables module: Add comments describing how the "strmap" logic works Fix up conflicts in scripts/mod/file2alias.c due to the new linker- generated table approach to adding __mod_*_device_table entries. The ARM sa11x0 mcp bus needed to be converted to that too.
2012-01-13cpumask: update setup_node_to_cpumask_map() commentsWanlong Gao1-1/+1
node_to_cpumask() has been replaced by cpumask_of_node(), and wholly removed since commit 29c337a0 ("cpumask: remove obsolete node_to_cpumask now everyone uses cpumask_of_node"). So update the comments for setup_node_to_cpumask_map(). Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-13module_param: make bool parameters really bool (arch)Rusty Russell1-2/+2
module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds6-40/+43
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/numa: Add constraints check for nid parameters mm, x86: Remove debug_pagealloc_enabled x86/mm: Initialize high mem before free_all_bootmem() arch/x86/kernel/e820.c: quiet sparse noise about plain integer as NULL pointer arch/x86/kernel/e820.c: Eliminate bubble sort from sanitize_e820_map() x86: Fix mmap random address range x86, mm: Unify zone_sizes_init() x86, mm: Prepare zone_sizes_init() for unification x86, mm: Use max_low_pfn for ZONE_NORMAL on 64-bit x86, mm: Wrap ZONE_DMA32 with CONFIG_ZONE_DMA32 x86, mm: Use max_pfn instead of highend_pfn x86, mm: Move zone init from paging_init() on 64-bit x86, mm: Use MAX_DMA_PFN for ZONE_DMA on 32-bit
2012-01-07Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Use "do { } while(0)" for empty lock_cmos()/unlock_cmos() macros x86: Use "do { } while(0)" for empty flush_tlb_fix_spurious_fault() macro x86, CPU: Drop superfluous get_cpu_cap() prototype arch/x86/mm/pageattr.c: Quiet sparse noise; local functions should be static arch/x86/kernel/ptrace.c: Quiet sparse noise x86: Use kmemdup() in copy_thread(), rather than duplicating its implementation x86: Replace the EVT_TO_HPET_DEV() macro with an inline function
2012-01-07Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2-7/+17
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86: Fix atomic64_xxx_cx8() functions x86: Fix and improve cmpxchg_double{,_local}() x86_64, asm: Optimise fls(), ffs() and fls64() x86, bitops: Move fls64.h inside __KERNEL__ x86: Fix and improve percpu_cmpxchg{8,16}b_double() x86: Report cpb and eff_freq_ro flags correctly x86/i386: Use less assembly in strlen(), speed things up a bit x86: Use the same node_distance for 32 and 64-bit x86: Fix rflags in FAKE_STACK_FRAME x86: Clean up and extend do_int3() x86: Call do_notify_resume() with interrupts enabled x86/div64: Add a micro-optimization shortcut if base is power of two x86-64: Cleanup some assembly entry points x86-64: Slightly shorten line system call entry and exit paths x86-64: Reduce amount of redundant code generated for invalidate_interruptNN x86-64: Slightly shorten int_ret_from_sys_call x86, efi: Convert efi_phys_get_time() args to physical addresses x86: Default to vsyscall=emulate x86-64: Set siginfo and context on vsyscall emulation faults x86: consolidate xchg and xadd macros ...
2012-01-07Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds1-1/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Skip cpus with apic-ids >= 255 in !x2apic_mode x86, x2apic: Allow "nox2apic" to disable x2apic mode setup by BIOS x86, x2apic: Fallback to xapic when BIOS doesn't setup interrupt-remapping x86, acpi: Skip acpi x2apic entries if the x2apic feature is not present x86, apic: Add probe() for apic_flat x86: Simplify code by removing a !SMP #ifdefs from 'struct cpuinfo_x86' x86: Convert per-cpu counter icr_read_retry_count into a member of irq_stat x86: Add per-cpu stat counter for APIC ICR read tries pci, x86/io-apic: Allow PCI_IOAPIC to be user configurable on x86 x86: Fix the !CONFIG_NUMA build of the new CPU ID fixup code support x86: Add NumaChip support x86: Add x86_init platform override to fix up NUMA core numbering x86: Make flat_init_apic_ldr() available
2012-01-04Merge commit 'v3.2-rc7' into x86/asmIngo Molnar2-0/+4
Merge reason: Update from -rc4 to -rc7. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-23x86, acpi: Skip acpi x2apic entries if the x2apic feature is not presentYinghai Lu1-1/+6
If the x2apic feature is not present (either the cpu is not capable of it or the user has disabled the feature using boot-parameter etc), ignore the x2apic MADT and SRAT entries provided by the ACPI tables. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/20111222014632.540896503@sbsiddha-desk.sc.intel.com Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-20Merge branch 'memblock-kill-early_node_map' of ↵Ingo Molnar10-439/+75
git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into core/memblock
2011-12-09thp: add compound tail page _mapcount when mappedYouquan Song1-0/+2
With the 3.2-rc kernel, IOMMU 2M pages in KVM works. But when I tried to use IOMMU 1GB pages in KVM, I encountered an oops and the 1GB page failed to be used. The root cause is that 1GB page allocation calls gup_huge_pud() while 2M page calls gup_huge_pmd. If compound pages are used and the page is a tail page, gup_huge_pmd() increases _mapcount to record tail page are mapped while gup_huge_pud does not do that. So when the mapped page is relesed, it will result in kernel oops because the page is not marked mapped. This patch add tail process for compound page in 1GB huge page which keeps the same process as 2M page. Reproduce like: 1. Add grub boot option: hugepagesz=1G hugepages=8 2. mount -t hugetlbfs -o pagesize=1G hugetlbfs /dev/hugepages 3. qemu-kvm -m 2048 -hda os-kvm.img -cpu kvm64 -smp 4 -mem-path /dev/hugepages -net none -device pci-assign,host=07:00.1 kernel BUG at mm/swap.c:114! invalid opcode: 0000 [#1] SMP Call Trace: put_page+0x15/0x37 kvm_release_pfn_clean+0x31/0x36 kvm_iommu_put_pages+0x94/0xb1 kvm_iommu_unmap_memslots+0x80/0xb6 kvm_assign_device+0xba/0x117 kvm_vm_ioctl_assigned_device+0x301/0xa47 kvm_vm_ioctl+0x36c/0x3a2 do_vfs_ioctl+0x49e/0x4e4 sys_ioctl+0x5a/0x7c system_call_fastpath+0x16/0x1b RIP put_compound_page+0xd4/0x168 Signed-off-by: Youquan Song <youquan.song@intel.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09x86/numa: Add constraints check for nid parametersPetr Holasek1-4/+6
This patch adds constraint checks to the numa_set_distance() function. When the check triggers (this should not happen normally) it emits a warning and avoids a store to a negative index in numa_distance[] array - i.e. avoids memory corruption. Negative ids can be passed when the pxm-to-nids mapping is not properly filled while parsing the SRAT. Signed-off-by: Petr Holasek <pholasek@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Anton Arapov <anton@redhat.com> Link: http://lkml.kernel.org/r/20111208121640.GA2229@dhcp-27-244.brq.redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06mm, x86: Remove debug_pagealloc_enabledStanislaw Gruszka1-6/+0
When (no)bootmem finish operation, it pass pages to buddy allocator. Since debug_pagealloc_enabled is not set, we will do not protect pages, what is not what we want with CONFIG_DEBUG_PAGEALLOC=y. To fix remove debug_pagealloc_enabled. That variable was introduced by commit 12d6f21e "x86: do not PSE on CONFIG_DEBUG_PAGEALLOC=y" to get more CPA (change page attribude) code testing. But currently we have CONFIG_CPA_DEBUG, which test CPA. Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1322582711-14571-1-git-send-email-sgruszka@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06x86/mm: Initialize high mem before free_all_bootmem()Stanislaw Gruszka1-2/+11
Patch fixes a boot crash with pagealloc debugging enabled: Initializing HighMem for node 0 (000377fe:0003fff0) BUG: unable to handle kernel paging request at f6fefe80 IP: [<c1621ab5>] find_range_array+0x5e/0x69 [...] Call Trace: [<c1622064>] __get_free_all_memory_range+0x39/0xb4 [<c1620dd0>] add_highpages_with_active_regions+0x18/0x9b [<c1621a2e>] set_highmem_pages_init+0x70/0x90 [<c162122b>] mem_init+0x50/0x21b [<c16155bd>] start_kernel+0x1bf/0x31c [<c1615065>] i386_start_kernel+0x65/0x67 The crash happens when memblock wants to allocate big area for temporary "struct range" array and reuses pages from top of low memory, which were already passed to the buddy allocator. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Cc: linux-mm@kvack.org Cc: Mel Gorman <mgorman@suse.de> Link: http://lkml.kernel.org/r/20111206080833.GB3105@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05arch/x86/mm/pageattr.c: Quiet sparse noise; local functions should be staticH Hartley Sweeten1-1/+1
Local functions should be marked static.  This also quiets the following sparse noise: warning: symbol '_set_memory_array' was not declared. Should it be static? Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: hartleys@visionengravers.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05x86: Fix mmap random address rangeLudwig Nussel1-2/+2
On x86_32 casting the unsigned int result of get_random_int() to long may result in a negative value. On x86_32 the range of mmap_rnd() therefore was -255 to 255. The 32bit mode on x86_64 used 0 to 255 as intended. The bug was introduced by 675a081 ("x86: unify mmap_{32|64}.c") in January 2008. Signed-off-by: Ludwig Nussel <ludwig.nussel@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: harvey.harrison@gmail.com Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/201111152246.pAFMklOB028527@wpaz5.hot.corp.google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>