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2018-10-03x86/mm/pat: Make set_memory_np() L1TF safeAndi Kleen1-2/+4
commit 958f79b9ee55dfaf00c8106ed1c22a2919e0028b upstream. set_memory_np() is used to mark kernel mappings not present, but it has it's own open coded mechanism which does not have the L1TF protection of inverting the address bits. Replace the open coded PTE manipulation with the L1TF protecting low level PTE routines. Passes the CPA self test. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [bwh: Backported to 3.16: - cpa->pfn is actually a physical address here and needs to be shifted to produce a PFN - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-09KAISER: Kernel Address IsolationRichard Fellner1-16/+47
This patch introduces our implementation of KAISER (Kernel Address Isolation to have Side-channels Efficiently Removed), a kernel isolation technique to close hardware side channels on kernel address information. More information about the patch can be found on: https://github.com/IAIK/KAISER From: Richard Fellner <richard.fellner@student.tugraz.at> From: Daniel Gruss <daniel.gruss@iaik.tugraz.at> Subject: [RFC, PATCH] x86_64: KAISER - do not map kernel in user mode Date: Thu, 4 May 2017 14:26:50 +0200 Link: http://marc.info/?l=linux-kernel&m=149390087310405&w=2 Kaiser-4.10-SHA1: c4b1831d44c6144d3762ccc72f0c4e71a0c713e5 To: <linux-kernel@vger.kernel.org> To: <kernel-hardening@lists.openwall.com> Cc: <clementine.maurice@iaik.tugraz.at> Cc: <moritz.lipp@iaik.tugraz.at> Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at> Cc: Richard Fellner <richard.fellner@student.tugraz.at> Cc: Ingo Molnar <mingo@kernel.org> Cc: <kirill.shutemov@linux.intel.com> Cc: <anders.fogh@gdata-adan.de> After several recent works [1,2,3] KASLR on x86_64 was basically considered dead by many researchers. We have been working on an efficient but effective fix for this problem and found that not mapping the kernel space when running in user mode is the solution to this problem [4] (the corresponding paper [5] will be presented at ESSoS17). With this RFC patch we allow anybody to configure their kernel with the flag CONFIG_KAISER to add our defense mechanism. If there are any questions we would love to answer them. We also appreciate any comments! Cheers, Daniel (+ the KAISER team from Graz University of Technology) [1] http://www.ieee-security.org/TC/SP2013/papers/4977a191.pdf [2] https://www.blackhat.com/docs/us-16/materials/us-16-Fogh-Using-Undocumented-CPU-Behaviour-To-See-Into-Kernel-Mode-And-Break-KASLR-In-The-Process.pdf [3] https://www.blackhat.com/docs/us-16/materials/us-16-Jang-Breaking-Kernel-Address-Space-Layout-Randomization-KASLR-With-Intel-TSX.pdf [4] https://github.com/IAIK/KAISER [5] https://gruss.cc/files/kaiser.pdf (cherry picked from Change-Id: I0eb000c33290af01fc4454ca0c701d00f1d30b1d) Conflicts: arch/x86/entry/entry_64.S (not in this tree) arch/x86/kernel/entry_64.S (patched instead of that) arch/x86/entry/entry_64_compat.S (not in this tree) arch/x86/ia32/ia32entry.S (patched instead of that) arch/x86/include/asm/hw_irq.h arch/x86/include/asm/pgtable_types.h arch/x86/include/asm/processor.h arch/x86/kernel/irqinit.c arch/x86/kernel/process.c arch/x86/mm/Makefile arch/x86/mm/pgtable.c init/main.c Signed-off-by: Hugh Dickins <hughd@google.com> [bwh: Folded in the follow-up patches from Hugh: - kaiser: merged update - kaiser: do not set _PAGE_NX on pgd_none - kaiser: stack map PAGE_SIZE at THREAD_SIZE-PAGE_SIZE - kaiser: fix build and FIXME in alloc_ldt_struct() - kaiser: KAISER depends on SMP - kaiser: fix regs to do_nmi() ifndef CONFIG_KAISER - kaiser: fix perf crashes - kaiser: ENOMEM if kaiser_pagetable_walk() NULL - kaiser: tidied up asm/kaiser.h somewhat - kaiser: tidied up kaiser_add/remove_mapping slightly - kaiser: kaiser_remove_mapping() move along the pgd - kaiser: align addition to x86/mm/Makefile - kaiser: cleanups while trying for gold link - kaiser: name that 0x1000 KAISER_SHADOW_PGD_OFFSET - kaiser: delete KAISER_REAL_SWITCH option - kaiser: vmstat show NR_KAISERTABLE as nr_overhead - kaiser: enhanced by kernel and user PCIDs - kaiser: load_new_mm_cr3() let SWITCH_USER_CR3 flush user - kaiser: PCID 0 for kernel and 128 for user - kaiser: x86_cr3_pcid_noflush and x86_cr3_pcid_user - kaiser: paranoid_entry pass cr3 need to paranoid_exit - kaiser: _pgd_alloc() without __GFP_REPEAT to avoid stalls - kaiser: fix unlikely error in alloc_ldt_struct() - kaiser: drop is_atomic arg to kaiser_pagetable_walk() Backported to 3.16: - Add missing #include in arch/x86/mm/kaiser.c - Use variable PEBS buffer size since we have "perf/x86/intel: Use PAGE_SIZE for PEBS buffer size on Core2" - Renumber X86_FEATURE_INVPCID_SINGLE to avoid collision - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-02-17x86/mm/pat: Avoid truncation when converting cpa->numpages to addressMatt Fleming1-2/+2
commit 742563777e8da62197d6cb4b99f4027f59454735 upstream. There are a couple of nasty truncation bugs lurking in the pageattr code that can be triggered when mapping EFI regions, e.g. when we pass a cpa->pgd pointer. Because cpa->numpages is a 32-bit value, shifting left by PAGE_SHIFT will truncate the resultant address to 32-bits. Viorel-Cătălin managed to trigger this bug on his Dell machine that provides a ~5GB EFI region which requires 1236992 pages to be mapped. When calling populate_pud() the end of the region gets calculated incorrectly in the following buggy expression, end = start + (cpa->numpages << PAGE_SHIFT); And only 188416 pages are mapped. Next, populate_pud() gets invoked for a second time because of the loop in __change_page_attr_set_clr(), only this time no pages get mapped because shifting the remaining number of pages (1048576) by PAGE_SHIFT is zero. At which point the loop in __change_page_attr_set_clr() spins forever because we fail to map progress. Hitting this bug depends very much on the virtual address we pick to map the large region at and how many pages we map on the initial run through the loop. This explains why this issue was only recently hit with the introduction of commit a5caa209ba9c ("x86/efi: Fix boot crash by mapping EFI memmap entries bottom-up at runtime, instead of top-down") It's interesting to note that safe uses of cpa->numpages do exist in the pageattr code. If instead of shifting ->numpages we multiply by PAGE_SIZE, no truncation occurs because PAGE_SIZE is a UL value, and so the result is unsigned long. To avoid surprises when users try to convert very large cpa->numpages values to addresses, change the data type from 'int' to 'unsigned long', thereby making it suitable for shifting by PAGE_SHIFT without any type casting. The alternative would be to make liberal use of casting, but that is far more likely to cause problems in the future when someone adds more code and fails to cast properly; this bug was difficult enough to track down in the first place. Reported-and-tested-by: Viorel-Cătălin Răpițeanu <rapiteanu.catalin@gmail.com> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Link: https://bugzilla.kernel.org/show_bug.cgi?id=110131 Link: http://lkml.kernel.org/r/1454067370-10374-1-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-11-13x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAEDexuan Cui1-1/+1
commit d1cd1210834649ce1ca6bafe5ac25d2f40331343 upstream. pte_pfn() returns a PFN of long (32 bits in 32-PAE), so "long << PAGE_SHIFT" will overflow for PFNs above 4GB. Due to this issue, some Linux 32-PAE distros, running as guests on Hyper-V, with 5GB memory assigned, can't load the netvsc driver successfully and hence the synthetic network device can't work (we can use the kernel parameter mem=3000M to work around the issue). Cast pte_pfn() to phys_addr_t before shifting. Fixes: "commit d76565344512: x86, mm: Create slow_virt_to_phys()" Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: gregkh@linuxfoundation.org Cc: linux-mm@kvack.org Cc: olaf@aepfle.de Cc: apw@canonical.com Cc: jasowang@redhat.com Cc: dave.hansen@intel.com Cc: riel@redhat.com Link: http://lkml.kernel.org/r/1414580017-27444-1-git-send-email-decui@microsoft.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2014-03-31Merge branch 'x86-efi-for-linus' of ↵Linus Torvalds1-17/+39
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 EFI changes from Ingo Molnar: "The main changes: - Add debug code to the dump EFI pagetable - Borislav Petkov - Make 1:1 runtime mapping robust when booting on machines with lots of memory - Borislav Petkov - Move the EFI facilities bits out of 'x86_efi_facility' and into efi.flags which is the standard architecture independent place to keep EFI state, by Matt Fleming. - Add 'EFI mixed mode' support: this allows 64-bit kernels to be booted from 32-bit firmware. This needs a bootloader that supports the 'EFI handover protocol'. By Matt Fleming" * 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits) x86, efi: Abstract x86 efi_early calls x86/efi: Restore 'attr' argument to query_variable_info() x86/efi: Rip out phys_efi_get_time() x86/efi: Preserve segment registers in mixed mode x86/boot: Fix non-EFI build x86, tools: Fix up compiler warnings x86/efi: Re-disable interrupts after calling firmware services x86/boot: Don't overwrite cr4 when enabling PAE x86/efi: Wire up CONFIG_EFI_MIXED x86/efi: Add mixed runtime services support x86/efi: Firmware agnostic handover entry points x86/efi: Split the boot stub into 32/64 code paths x86/efi: Add early thunk code to go from 64-bit to 32-bit x86/efi: Build our own EFI services pointer table efi: Add separate 32-bit/64-bit definitions x86/efi: Delete dead code when checking for non-native x86/mm/pageattr: Always dump the right page table in an oops x86, tools: Consolidate #ifdef code x86/boot: Cleanup header.S by removing some #ifdefs efi: Use NULL instead of 0 for pointer ...
2014-03-31Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu handling changes from Ingo Molnar: "Bigger changes: - Intel CPU hardware-enablement: new vector instructions support (AVX-512), by Fenghua Yu. - Support the clflushopt instruction and use it in appropriate places. clflushopt is similar to clflush but with more relaxed ordering, by Ross Zwisler. - MSR accessor cleanups, by Borislav Petkov. - 'forcepae' boot flag for those who have way too much time to spend on way too old Pentium-M systems and want to live way too dangerously, by Chris Bainbridge" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC x86, intel: Make MSR_IA32_MISC_ENABLE bit constants systematic x86, Intel: Convert to the new bit access MSR accessors x86, AMD: Convert to the new bit access MSR accessors x86: Add another set of MSR accessor functions x86: Use clflushopt in drm_clflush_virt_range x86: Use clflushopt in drm_clflush_page x86: Use clflushopt in clflush_cache_range x86: Add support for the clflushopt instruction x86, AVX-512: Enable AVX-512 States Context Switch x86, AVX-512: AVX-512 Feature Detection
2014-03-14x86, pageattr: Correct WBINVD spelling in commentBorislav Petkov1-3/+3
It is WBINVD, for INValiDate and not "wbindv". Use caps for instruction names, while at it. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1394633584-5509-4-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-05Merge remote-tracking branch 'tip/x86/efi-mixed' into efi-for-mingoMatt Fleming1-4/+8
Conflicts: arch/x86/kernel/setup.c arch/x86/platform/efi/efi.c arch/x86/platform/efi/efi_64.c
2014-03-05x86/mm/pageattr: Always dump the right page table in an oopsMatt Fleming1-4/+8
Now that we have EFI-specific page tables we need to lookup the pgd when dumping those page tables, rather than assuming that swapper_pgdir is the current pgdir. Remove the double underscore prefix, which is usually reserved for static functions. Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04x86, pageattr: Export page unmapping interfaceBorislav Petkov1-13/+31
We will use it in efi so expose it. Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-02-27x86: Use clflushopt in clflush_cache_rangeRoss Zwisler1-4/+4
If clflushopt is available on the system, use it instead of clflush in clflush_cache_range. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Link: http://lkml.kernel.org/r/1393441612-19729-3-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-11-02x86/mm/cpa: Map in an arbitrary pgdBorislav Petkov1-7/+46
Add the ability to map pages in an arbitrary pgd. This wires in the remaining stuff so that there's a new interface with which you can map a region into an arbitrary PGD. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-11-02x86/mm/pageattr: Add last levels of error pathBorislav Petkov1-1/+93
We try to free the pagetable pages once we've unmapped our portion. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-11-02x86/mm/pageattr: Add a PUD error unwinding pathBorislav Petkov1-2/+58
In case we encounter an error during the mapping of a region, we want to unwind what we've established so far exactly the way we did the mapping. This is the PUD part kept deliberately small for easier review. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-11-02x86/mm/pageattr: Add a PTE pagetable populating functionBorislav Petkov1-1/+21
Handle last level by unconditionally writing the PTEs into the PTE page while paying attention to the NX bit. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-11-02x86/mm/pageattr: Add a PMD pagetable populating functionBorislav Petkov1-1/+81
Handle PMD-level mappings the same as PUD ones. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-11-02x86/mm/pageattr: Add a PUD pagetable populating functionBorislav Petkov1-1/+86
Add the next level of the pagetable populating function, we handle chunks around a 1G boundary by mapping them with the lower level functions - otherwise we use 1G pages for the mappings, thus using as less amount of pagetable pages as possible. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-11-02x86/mm/pageattr: Add a PGD pagetable populating functionBorislav Petkov1-0/+39
This allocates, if necessary, and populates the corresponding PGD entry with a PUD page. The next population level is a dummy macro which will be removed by the next patch and it is added here to keep the patch small and easily reviewable but not break bisection, at the same time. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-11-02x86/mm/pageattr: Lookup address in an arbitrary PGDBorislav Petkov1-10/+26
This is preparatory work in order to be able to map pages into a specified PGD and not implicitly and only into init_mm. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-04-30Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds1-5/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm changes from Ingo Molnar: "Misc smaller changes all over the map" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/iommu/dmar: Remove warning for HPET scope type x86/mm/gart: Drop unnecessary check x86/mm/hotplug: Put kernel_physical_mapping_remove() declaration in CONFIG_MEMORY_HOTREMOVE x86/mm/fixmap: Remove unused FIX_CYCLONE_TIMER x86/mm/numa: Simplify some bit mangling x86/mm: Re-enable DEBUG_TLBFLUSH for X86_32 x86/mm/cpa: Cleanup split_large_page() and its callee x86: Drop always empty .text..page_aligned section
2013-04-12x86/mm: Flush lazy MMU when DEBUG_PAGEALLOC is setBoris Ostrovsky1-0/+2
When CONFIG_DEBUG_PAGEALLOC is set page table updates made by kernel_map_pages() are not made visible (via TLB flush) immediately if lazy MMU is on. In environments that support lazy MMU (e.g. Xen) this may lead to fatal page faults, for example, when zap_pte_range() needs to allocate pages in __tlb_remove_page() -> tlb_next_batch(). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: konrad.wilk@oracle.com Link: http://lkml.kernel.org/r/1365703192-2089-1-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-04-11x86/mm/cpa: Convert noop to functional fixAndrea Arcangeli1-5/+5
Commit: a8aed3e0752b ("x86/mm/pageattr: Prevent PSE and GLOABL leftovers to confuse pmd/pte_present and pmd_huge") introduced a valid fix but one location that didn't trigger the bug that lead to finding those (small) problems, wasn't updated using the right variable. The wrong variable was also initialized for no good reason, that may have been the source of the confusion. Remove the noop initialization accordingly. Commit a8aed3e0752b also erroneously removed one canon_pgprot pass meant to clear pmd bitflags not supported in hardware by older CPUs, that automatically gets corrected by this patch too by applying it to the right variable in the new location. Reported-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Andy Whitcroft <apw@canonical.com> Cc: Mel Gorman <mgorman@suse.de> Link: http://lkml.kernel.org/r/1365600505-19314-1-git-send-email-aarcange@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-04-10x86/mm/cpa: Cleanup split_large_page() and its calleeBorislav Petkov1-5/+4
So basically we're generating the pte_t * from a struct page and we're handing it down to the __split_large_page() internal version which then goes and gets back struct page * from it because it needs it. Change the caller to hand down struct page * directly and the callee can compute the pte_t itself. Net save is one virt_to_page() call and simpler code. While at it, make __split_large_page() static. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1363886217-24703-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-27Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-3/+47
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm/pageattr: Prevent PSE and GLOABL leftovers to confuse pmd/pte_present and pmd_huge Revert "x86, mm: Make spurious_fault check explicitly check explicitly check the PRESENT bit" x86/mm/numa: Don't check if node is NUMA_NO_NODE x86, efi: Make "noefi" really disable EFI runtime serivces x86/apic: Fix parsing of the 'lapic' cmdline option
2013-02-24x86/mm/pageattr: Prevent PSE and GLOABL leftovers to confuse pmd/pte_present ↵Andrea Arcangeli1-3/+47
and pmd_huge Without this patch any kernel code that reads kernel memory in non present kernel pte/pmds (as set by pageattr.c) will crash. With this kernel code: static struct page *crash_page; static unsigned long *crash_address; [..] crash_page = alloc_pages(GFP_KERNEL, 9); crash_address = page_address(crash_page); if (set_memory_np((unsigned long)crash_address, 1)) printk("set_memory_np failure\n"); [..] The kernel will crash if inside the "crash tool" one would try to read the memory at the not present address. crash> p crash_address crash_address = $8 = (long unsigned int *) 0xffff88023c000000 crash> rd 0xffff88023c000000 [ *lockup* ] The lockup happens because _PAGE_GLOBAL and _PAGE_PROTNONE shares the same bit, and pageattr leaves _PAGE_GLOBAL set on a kernel pte which is then mistaken as _PAGE_PROTNONE (so pte_present returns true by mistake and the kernel fault then gets confused and loops). With THP the same can happen after we taught pmd_present to check _PAGE_PROTNONE and _PAGE_PSE in commit 027ef6c87853b0a9df5317 ("mm: thp: fix pmd_present for split_huge_page and PROT_NONE with THP"). THP has the same problem with _PAGE_GLOBAL as the 4k pages, but it also has a problem with _PAGE_PSE, which must be cleared too. After the patch is applied copy_user correctly returns -EFAULT and doesn't lockup anymore. crash> p crash_address crash_address = $9 = (long unsigned int *) 0xffff88023c000000 crash> rd 0xffff88023c000000 rd: read error: kernel virtual address: ffff88023c000000 type: "64-bit KVADDR" Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Shaohua Li <shaohua.li@intel.com> Cc: "H. Peter Anvin" <hpa@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-24memory-hotplug: common APIs to support page tables hot-removeWen Congyang1-22/+25
When memory is removed, the corresponding pagetables should alse be removed. This patch introduces some common APIs to support vmemmap pagetable and x86_64 architecture direct mapping pagetable removing. All pages of virtual mapping in removed memory cannot be freed if some pages used as PGD/PUD include not only removed memory but also other memory. So this patch uses the following way to check whether a page can be freed or not. 1) When removing memory, the page structs of the removed memory are filled with 0FD. 2) All page structs are filled with 0xFD on PT/PMD, PT/PMD can be cleared. In this case, the page used as PT/PMD can be freed. For direct mapping pages, update direct_pages_count[level] when we freed their pagetables. And do not free the pages again because they were freed when offlining. For vmemmap pages, free the pages and their pagetables. For larger pages, do not split them into smaller ones because there is no way to know if the larger page has been split. As a result, there is no way to decide when to split. We deal the larger pages in the following way: 1) For direct mapped pages, all the pages were freed when they were offlined. And since menmory offline is done section by section, all the memory ranges being removed are aligned to PAGE_SIZE. So only need to deal with unaligned pages when freeing vmemmap pages. 2) For vmemmap pages being used to store page_struct, if part of the larger page is still in use, just fill the unused part with 0xFD. And when the whole page is fulfilled with 0xFD, then free the larger page. [akpm@linux-foundation.org: fix typo in comment] [tangchen@cn.fujitsu.com: do not calculate direct mapping pages when freeing vmemmap pagetables] [tangchen@cn.fujitsu.com: do not free direct mapping pages twice] [tangchen@cn.fujitsu.com: do not free page split from hugepage one by one] [tangchen@cn.fujitsu.com: do not split pages when freeing pagetable pages] [akpm@linux-foundation.org: use pmd_page_vaddr()] [akpm@linux-foundation.org: fix used-uninitialised bug] Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Wu Jianguo <wujianguo@huawei.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>
2013-02-01Merge remote-tracking branch 'origin/x86/mm' into x86/mm2H. Peter Anvin1-11/+39
Explicitly merging these two branches due to nontrivial conflicts and to allow further work. Resolved Conflicts: arch/x86/kernel/head32.c arch/x86/kernel/head64.c arch/x86/mm/init_64.c arch/x86/realmode/init.c Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-26x86, mm: Create slow_virt_to_phys()Dave Hansen1-0/+31
This is necessary because __pa() does not work on some kinds of memory, like vmalloc() or the alloc_remap() areas on 32-bit NUMA systems. We have some functions to do conversions _like_ this in the vmalloc() code (like vmalloc_to_page()), but they do not work on sizes other than 4k pages. We would potentially need to be able to handle all the page sizes that we use for the kernel linear mapping (4k, 2M, 1G). In practice, on 32-bit NUMA systems, the percpu areas get stuck in the alloc_remap() area. Any __pa() call on them will break and basically return garbage. This patch introduces a new function slow_virt_to_phys(), which walks the kernel page tables on x86 and should do precisely the same logical thing as __pa(), but actually work on a wider range of memory. It should work on the normal linear mapping, vmalloc(), kmap(), etc... Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20130122212433.4D1FCA62@kernel.stglabs.ibm.com Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-26x86, mm: Use new pagetable helpers in try_preserve_large_page()Dave Hansen1-7/+4
try_preserve_large_page() can be slightly simplified by using the new page_level_*() helpers. This also moves the 'level' over to the new pg_level enum type. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20130122212432.14F3D993@kernel.stglabs.ibm.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-12-16Revert "x86-64/efi: Use EFI to deal with platform wall clock (again)"Linus Torvalds1-6/+4
This reverts commit bd52276fa1d4 ("x86-64/efi: Use EFI to deal with platform wall clock (again)"), and the two supporting commits: da5a108d05b4: "x86/kernel: remove tboot 1:1 page table creation code" 185034e72d59: "x86, efi: 1:1 pagetable mapping for virtual EFI calls") as they all depend semantically on commit 53b87cf088e2 ("x86, mm: Include the entire kernel memory map in trampoline_pgd") that got reverted earlier due to the problems it caused. This was pointed out by Yinghai Lu, and verified by me on my Macbook Air that uses EFI. Pointed-out-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-17x86, mm: use pfn_range_is_mapped() with CPAYinghai Lu1-13/+3
We are going to map ram only, so under max_low_pfn_mapped, between 4g and max_pfn_mapped does not mean mapped at all. Use pfn_range_is_mapped() directly. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1353123563-3103-13-git-send-email-yinghai@kernel.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-11-17x86: Use __pa_symbol instead of __pa on C visible symbolsAlexander Duyck1-4/+4
When I made an attempt at separating __pa_symbol and __pa I found that there were a number of cases where __pa was used on an obvious symbol. I also caught one non-obvious case as _brk_start and _brk_end are based on the address of __brk_base which is a C visible symbol. In mark_rodata_ro I was able to reduce the overhead of kernel symbol to virtual memory translation by using a combination of __va(__pa_symbol()) instead of page_address(virt_to_page()). Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Link: http://lkml.kernel.org/r/20121116215640.8521.80483.stgit@ahduyck-cp1.jf.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-10-30x86-64/efi: Use EFI to deal with platform wall clock (again)Jan Beulich1-4/+6
Other than ix86, x86-64 on EFI so far didn't set the {g,s}et_wallclock accessors to the EFI routines, thus incorrectly using raw RTC accesses instead. Simply removing the #ifdef around the respective code isn't enough, however: While so far early get-time calls were done in physical mode, this doesn't work properly for x86-64, as virtual addresses would still need to be set up for all runtime regions (which wasn't the case on the system I have access to), so instead the patch moves the call to efi_enter_virtual_mode() ahead (which in turn allows to drop all code related to calling efi-get-time in physical mode). Additionally the earlier calling of efi_set_executable() requires the CPA code to cope, i.e. during early boot it must be avoided to call cpa_flush_array(), as the first thing this function does is a BUG_ON(irqs_disabled()). Also make the two EFI functions in question here static - they're not being referenced elsewhere. History: This commit was originally merged as bacef661acdb ("x86-64/efi: Use EFI to deal with platform wall clock") but it resulted in some ASUS machines no longer booting due to a firmware bug, and so was reverted in f026cfa82f62. A pre-emptive fix for the buggy ASUS firmware was merged in 03a1c254975e ("x86, efi: 1:1 pagetable mapping for virtual EFI calls") so now this patch can be reapplied. Signed-off-by: Jan Beulich <jbeulich@suse.com> Tested-by: Matt Fleming <matt.fleming@intel.com> Acked-by: Matthew Garrett <mjg@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> [added commit history]
2012-08-14Revert "x86-64/efi: Use EFI to deal with platform wall clock"H. Peter Anvin1-6/+4
This reverts commit bacef661acdb634170a8faddbc1cf28e8f8b9eee. This commit has been found to cause serious regressions on a number of ASUS machines at the least. We probably need to provide a 1:1 map in addition to the EFI virtual memory map in order for this to work. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Reported-and-bisected-by: Jérôme Carretero <cJ-ko@zougloub.eu> Cc: Jan Beulich <jbeulich@suse.com> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Matthew Garrett <mjg@redhat.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/20120805172903.5f8bb24c@zougloub.eu
2012-07-27Merge branch 'x86-efi-for-linus' of ↵Linus Torvalds1-4/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pul x86/efi changes from Ingo Molnar: "This tree adds an EFI bootloader handover protocol, which, once supported on the bootloader side, will make bootup faster and might result in simpler bootloaders. The other change activates the EFI wall clock time accessors on x86-64 as well, instead of the legacy RTC readout." * 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, efi: Handover Protocol x86-64/efi: Use EFI to deal with platform wall clock
2012-06-11x86/mm: Fix some kernel-doc warningsWanpeng Li1-1/+1
Fix kernel-doc warnings in arch/x86/mm/ioremap.c and arch/x86/mm/pageattr.c, just like this one: Warning(arch/x86/mm/ioremap.c:204): No description found for parameter 'phys_addr' Warning(arch/x86/mm/ioremap.c:204): Excess function parameter 'offset' description in 'ioremap_nocache' Signed-off-by: Wanpeng Li <liwp@linux.vnet.ibm.com> Cc: Gavin Shan <shangw@linux.vnet.ibm.com> Cc: Wanpeng Li <liwp.linux@gmail.com> Link: http://lkml.kernel.org/r/1339296652-2935-1-git-send-email-liwp.linux@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86-64/efi: Use EFI to deal with platform wall clockJan Beulich1-4/+6
Other than ix86, x86-64 on EFI so far didn't set the {g,s}et_wallclock accessors to the EFI routines, thus incorrectly using raw RTC accesses instead. Simply removing the #ifdef around the respective code isn't enough, however: While so far early get-time calls were done in physical mode, this doesn't work properly for x86-64, as virtual addresses would still need to be set up for all runtime regions (which wasn't the case on the system I have access to), so instead the patch moves the call to efi_enter_virtual_mode() ahead (which in turn allows to drop all code related to calling efi-get-time in physical mode). Additionally the earlier calling of efi_set_executable() requires the CPA code to cope, i.e. during early boot it must be avoided to call cpa_flush_array(), as the first thing this function does is a BUG_ON(irqs_disabled()). Also make the two EFI functions in question here static - they're not being referenced elsewhere. Signed-off-by: Jan Beulich <jbeulich@suse.com> Tested-by: Matt Fleming <matt.fleming@intel.com> Acked-by: Matthew Garrett <mjg@redhat.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/4FBFBF5F020000780008637F@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-01-12Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds1-6/+0
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
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>
2011-12-05arch/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>
2011-03-18x86: Fix common misspellingsLucas De Marchi1-1/+1
They were generated by 'codespell' and then manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: trivial@kernel.org LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-10x86/mm: Fix pgd_lock deadlockAndrea Arcangeli1-10/+8
It's forbidden to take the page_table_lock with the irq disabled or if there's contention the IPIs (for tlb flushes) sent with the page_table_lock held will never run leading to a deadlock. Nobody takes the pgd_lock from irq context so the _irqsave can be removed. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> LKML-Reference: <201102162345.p1GNjMjm021738@imap1.linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-03x86, nx: Don't force pages RW when setting NX bitsMatthieu CASTET1-8/+0
Xen want page table pages read only. But the initial page table (from head_*.S) live in .data or .bss. That was broken by 64edc8ed5ffae999d8d413ba006850e9e34166cb. There is absolutely no reason to force these pages RW after they have already been marked RO. Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-11-18x86: Add NX protection for kernel dataMatthieu Castet1-1/+4
This patch expands functionality of CONFIG_DEBUG_RODATA to set main (static) kernel data area as NX. The following steps are taken to achieve this: 1. Linker script is adjusted so .text always starts and ends on a page bound 2. Linker script is adjusted so .rodata always start and end on a page boundary 3. NX is set for all pages from _etext through _end in mark_rodata_ro. 4. free_init_pages() sets released memory NX in arch/x86/mm/init.c 5. bios rom is set to x when pcibios is used. The results of patch application may be observed in the diff of kernel page table dumps: pcibios: -- data_nx_pt_before.txt 2009-10-13 07:48:59.000000000 -0400 ++ data_nx_pt_after.txt 2009-10-13 07:26:46.000000000 -0400 0x00000000-0xc0000000 3G pmd ---[ Kernel Mapping ]--- -0xc0000000-0xc0100000 1M RW GLB x pte +0xc0000000-0xc00a0000 640K RW GLB NX pte +0xc00a0000-0xc0100000 384K RW GLB x pte -0xc0100000-0xc03d7000 2908K ro GLB x pte +0xc0100000-0xc0318000 2144K ro GLB x pte +0xc0318000-0xc03d7000 764K ro GLB NX pte -0xc03d7000-0xc0600000 2212K RW GLB x pte +0xc03d7000-0xc0600000 2212K RW GLB NX pte 0xc0600000-0xf7a00000 884M RW PSE GLB NX pmd 0xf7a00000-0xf7bfe000 2040K RW GLB NX pte 0xf7bfe000-0xf7c00000 8K pte No pcibios: -- data_nx_pt_before.txt 2009-10-13 07:48:59.000000000 -0400 ++ data_nx_pt_after.txt 2009-10-13 07:26:46.000000000 -0400 0x00000000-0xc0000000 3G pmd ---[ Kernel Mapping ]--- -0xc0000000-0xc0100000 1M RW GLB x pte +0xc0000000-0xc0100000 1M RW GLB NX pte -0xc0100000-0xc03d7000 2908K ro GLB x pte +0xc0100000-0xc0318000 2144K ro GLB x pte +0xc0318000-0xc03d7000 764K ro GLB NX pte -0xc03d7000-0xc0600000 2212K RW GLB x pte +0xc03d7000-0xc0600000 2212K RW GLB NX pte 0xc0600000-0xf7a00000 884M RW PSE GLB NX pmd 0xf7a00000-0xf7bfe000 2040K RW GLB NX pte 0xf7bfe000-0xf7c00000 8K pte The patch has been originally developed for Linux 2.6.34-rc2 x86 by Siarhei Liakh <sliakh.lkml@gmail.com> and Xuxian Jiang <jiang@cs.ncsu.edu>. -v1: initial patch for 2.6.30 -v2: patch for 2.6.31-rc7 -v3: moved all code into arch/x86, adjusted credits -v4: fixed ifdef, removed credits from CREDITS -v5: fixed an address calculation bug in mark_nxdata_nx() -v6: added acked-by and PT dump diff to commit log -v7: minor adjustments for -tip -v8: rework with the merge of "Set first MB as RW+NX" Signed-off-by: Siarhei Liakh <sliakh.lkml@gmail.com> Signed-off-by: Xuxian Jiang <jiang@cs.ncsu.edu> Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr> Cc: Arjan van de Ven <arjan@infradead.org> Cc: James Morris <jmorris@namei.org> Cc: Andi Kleen <ak@muc.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Dave Jones <davej@redhat.com> Cc: Kees Cook <kees.cook@canonical.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <4CE2F82E.60601@free.fr> [ minor cleanliness edits ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-18x86: Fix improper large page preservationmatthieu castet1-10/+18
This patch fixes a bug in try_preserve_large_page() which may result in improper large page preservation and improper application of page attributes to the memory area outside of the original change request. More specifically, the problem manifests itself when set_memory_*() is called for several pages at the beginning of the large page and try_preserve_large_page() erroneously concludes that the change can be applied to whole large page. The fix consists of 3 parts: 1. Addition of "required" protection attributes in static_protections(), so .data and .bss can be guaranteed to stay "RW" 2. static_protections() is now called for every small page within large page to determine compatibility of new protection attributes (instead of just small pages within the requested range). 3. Large page can be preserved only if attribute change is large-page-aligned and covers whole large page. -v1: Try_preserve_large_page() patch for Linux 2.6.34-rc2 -v2: Replaced pfn check with address check for kernel rw-data Signed-off-by: Siarhei Liakh <sliakh.lkml@gmail.com> Signed-off-by: Xuxian Jiang <jiang@cs.ncsu.edu> Reviewed-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: James Morris <jmorris@namei.org> Cc: Andi Kleen <ak@muc.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Dave Jones <davej@redhat.com> Cc: Kees Cook <kees.cook@canonical.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <4CE2F7F3.8030809@free.fr> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-20Merge branch 'drm-ttm-pool' into drm-core-nextDave Airlie1-8/+45
* drm-ttm-pool: drm/ttm: using kmalloc/kfree requires including slab.h drm/ttm: include linux/seq_file.h for seq_printf drm/ttm: Add sysfs interface to control pool allocator. drm/ttm: Use set_pages_array_wc instead of set_memory_wc. arch/x86: Add array variants for setting memory to wc caching. drm/nouveau: Add ttm page pool debugfs file. drm/radeon/kms: Add ttm page pool debugfs file. drm/ttm: Add debugfs output entry to pool allocator. drm/ttm: add pool wc/uc page allocator V3
2010-04-06arch/x86: Add array variants for setting memory to wc caching.Pauli Nieminen1-8/+45
Setting single memory pages at a time to wc takes a lot time in cache flush. To reduce number of cache flush set_pages_array_wc and set_memory_array_wc can be used to set multiple pages to WC with single cache flush. This improves allocation performance for wc cached pages in drm/ttm. CC: Suresh Siddha <suresh.b.siddha@intel.com> CC: Venkatesh Pallipadi <venkatesh.pallipadi@gmail.com> Signed-off-by: Pauli Nieminen <suokkos@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-1/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-02-23x86_64, cpa: Don't work hard in preserving kernel 2M mappings when using 4K ↵Suresh Siddha1-2/+23
already We currently enforce the !RW mapping for the kernel mapping that maps holes between different text, rodata and data sections. However, kernel identity mappings will have different RWX permissions to the pages mapping to text and to the pages padding (which are freed) the text, rodata sections. Hence kernel identity mappings will be broken to smaller pages. For 64-bit, kernel text and kernel identity mappings are different, so we can enable protection checks that come with CONFIG_DEBUG_RODATA, as well as retain 2MB large page mappings for kernel text. Konrad reported a boot failure with the Linux Xen paravirt guest because of this. In this paravirt guest case, the kernel text mapping and the kernel identity mapping share the same page-table pages. Thus forcing the !RW mapping for some of the kernel mappings also cause the kernel identity mappings to be read-only resulting in the boot failure. Linux Xen paravirt guest also uses 4k mappings and don't use 2M mapping. Fix this issue and retain large page performance advantage for native kernels by not working hard and not enforcing !RW for the kernel text mapping, if the current mapping is already using small page mapping. Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <1266522700.2909.34.camel@sbs-t61.sc.intel.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: stable@kernel.org [2.6.32, 2.6.33] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-11-17x86, pageattr: Make set_memory_(x|nx) aware of NX supportH. Peter Anvin1-0/+6
Make set_memory_x/set_memory_nx directly aware of if NX is supported in the system or not, rather than requiring that every caller assesses that support independently. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tejun Heo <tj@kernel.org> Cc: Tim Starling <tstarling@wikimedia.org> Cc: Hannes Eder <hannes@hanneseder.net> LKML-Reference: <1258154897-6770-4-git-send-email-hpa@zytor.com> Acked-by: Kees Cook <kees.cook@canonical.com>
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