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2018-11-01Merge tag 'stackleak-v4.20-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull stackleak gcc plugin from Kees Cook: "Please pull this new GCC plugin, stackleak, for v4.20-rc1. This plugin was ported from grsecurity by Alexander Popov. It provides efficient stack content poisoning at syscall exit. This creates a defense against at least two classes of flaws: - Uninitialized stack usage. (We continue to work on improving the compiler to do this in other ways: e.g. unconditional zero init was proposed to GCC and Clang, and more plugin work has started too). - Stack content exposure. By greatly reducing the lifetime of valid stack contents, exposures via either direct read bugs or unknown cache side-channels become much more difficult to exploit. This complements the existing buddy and heap poisoning options, but provides the coverage for stacks. The x86 hooks are included in this series (which have been reviewed by Ingo, Dave Hansen, and Thomas Gleixner). The arm64 hooks have already been merged through the arm64 tree (written by Laura Abbott and reviewed by Mark Rutland and Will Deacon). With VLAs having been removed this release, there is no need for alloca() protection, so it has been removed from the plugin" * tag 'stackleak-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: arm64: Drop unneeded stackleak_check_alloca() stackleak: Allow runtime disabling of kernel stack erasing doc: self-protection: Add information about STACKLEAK feature fs/proc: Show STACKLEAK metrics in the /proc file system lkdtm: Add a test for STACKLEAK gcc-plugins: Add STACKLEAK plugin for tracking the kernel stack x86/entry: Add STACKLEAK erasing the kernel stack at the end of syscalls
2018-10-26mm: remove references to vm_insert_pfn()Matthew Wilcox
Documentation and comments. Link: http://lkml.kernel.org/r/20180828145728.11873-7-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Souptick Joarder <jrdr.linux@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-24Merge tag 'docs-4.20' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This is a fairly typical cycle for documentation. There's some welcome readability improvements for the formatted output, some LICENSES updates including the addition of the ISC license, the removal of the unloved and unmaintained 00-INDEX files, the deprecated APIs document from Kees, more MM docs from Mike Rapoport, and the usual pile of typo fixes and corrections" * tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits) docs: Fix typos in histogram.rst docs: Introduce deprecated APIs list kernel-doc: fix declaration type determination doc: fix a typo in adding-syscalls.rst docs/admin-guide: memory-hotplug: remove table of contents doc: printk-formats: Remove bogus kobject references for device nodes Documentation: preempt-locking: Use better example dm flakey: Document "error_writes" feature docs/completion.txt: Fix a couple of punctuation nits LICENSES: Add ISC license text LICENSES: Add note to CDDL-1.0 license that it should not be used docs/core-api: memory-hotplug: add some details about locking internals docs/core-api: rename memory-hotplug-notifier to memory-hotplug docs: improve readability for people with poorer eyesight yama: clarify ptrace_scope=2 in Yama documentation docs/vm: split memory hotplug notifier description to Documentation/core-api docs: move memory hotplug description into admin-guide/mm doc: Fix acronym "FEKEK" in ecryptfs docs: fix some broken documentation references iommu: Fix passthrough option documentation ...
2018-10-23Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Ingo Molnar: "Lots of changes in this cycle: - Lots of CPA (change page attribute) optimizations and related cleanups (Thomas Gleixner, Peter Zijstra) - Make lazy TLB mode even lazier (Rik van Riel) - Fault handler cleanups and improvements (Dave Hansen) - kdump, vmcore: Enable kdumping encrypted memory with AMD SME enabled (Lianbo Jiang) - Clean up VM layout documentation (Baoquan He, Ingo Molnar) - ... plus misc other fixes and enhancements" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits) x86/stackprotector: Remove the call to boot_init_stack_canary() from cpu_startup_entry() x86/mm: Kill stray kernel fault handling comment x86/mm: Do not warn about PCI BIOS W+X mappings resource: Clean it up a bit resource: Fix find_next_iomem_res() iteration issue resource: Include resource end in walk_*() interfaces x86/kexec: Correct KEXEC_BACKUP_SRC_END off-by-one error x86/mm: Remove spurious fault pkey check x86/mm/vsyscall: Consider vsyscall page part of user address space x86/mm: Add vsyscall address helper x86/mm: Fix exception table comments x86/mm: Add clarifying comments for user addr space x86/mm: Break out user address space handling x86/mm: Break out kernel address space handling x86/mm: Clarify hardware vs. software "error_code" x86/mm/tlb: Make lazy TLB mode lazier x86/mm/tlb: Add freed_tables element to flush_tlb_info x86/mm/tlb: Add freed_tables argument to flush_tlb_mm_range smp,cpumask: introduce on_each_cpu_cond_mask smp: use __cpumask_set_cpu in on_each_cpu_cond ...
2018-10-23Merge branch 'x86-grub2-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 grub2 updates from Ingo Molnar: "This extends the x86 boot protocol to include an address for the RSDP table - utilized by Xen currently. Matching Grub2 patches are pending as well. (Juergen Gross)" * 'x86-grub2-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/acpi, x86/boot: Take RSDP address for boot params if available x86/boot: Add ACPI RSDP address to setup_header x86/xen: Fix boot loader version reported for PVH guests
2018-10-10x86/boot: Add ACPI RSDP address to setup_headerJuergen Gross
Xen PVH guests receive the address of the RSDP table from Xen. In order to support booting a Xen PVH guest via Grub2 using the standard x86 boot entry we need a way for Grub2 to pass the RSDP address to the kernel. For this purpose expand the struct setup_header to hold the physical address of the RSDP address. Being zero means it isn't specified and has to be located the legacy way (searching through low memory or EBDA). While documenting the new setup_header layout and protocol version 2.14 add the missing documentation of protocol version 2.13. There are Grub2 versions in several distros with a downstream patch violating the boot protocol by writing past the end of setup_header. This requires another update of the boot protocol to enable the kernel to distinguish between a specified RSDP address and one filled with garbage by such a broken Grub2. From protocol 2.14 on Grub2 will write the version it is supporting (but never a higher value than found to be supported by the kernel) ored with 0x8000 to the version field of setup_header. This enables the kernel to know up to which field Grub2 has written information to. All fields after that are supposed to be clobbered. Signed-off-by: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boris.ostrovsky@oracle.com Cc: bp@alien8.de Cc: corbet@lwn.net Cc: linux-doc@vger.kernel.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20181010061456.22238-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-06x86/mm/doc: Enhance the x86-64 virtual memory layout descriptionsIngo Molnar
After the cleanups from Baoquan He, make it even more readable: - Remove the 'bits' area size column: it's pretty pointless and was even wrong for some of the entries. Given that MB, GB, TB, PT are 10, 20, 30 and 40 bits, a "8 TB" size description makes it obvious that it's 43 bits. - Introduce an "offset" column: -------------------------------------------------------------------------------- start addr | offset | end addr | size | VM area description -----------------|------------|------------------|---------|-------------------- ... ffff880000000000 | -120 TB | ffffc7ffffffffff | 64 TB | direct mapping of all physical memory (page_offset_base), this is what limits max physical memory supported. The -120 TB notation makes it obvious where this particular virtual memory region starts: 120 TB down from the top of the 64-bit virtual memory space. Especially the layout of the kernel mappings is a *lot* more obvious when written this way, plus it's much easier to compare it with the size column and understand/check/validate and modify the kernel's layout in the future. - Mark the part from where the 47-bit and 56-bit kernel layouts are 100% identical, this starts at the -512 GB offset and the EFI region. - Re-shuffle the size desciptions to be continous blocks of sizes, instead of the often mixed size. I.e. write "0.5 TB" instead of "512 GB" if we are still in the TB-granular region of the map. - Make the 47-bit and 56-bit descriptions use the *exact* same layout and wording, and only differ where there's a material difference. This makes it easy to compare the two tables side by side by switching between two terminal tabs. - Plus enhance a lot of other stylistic/typographical details: make the tables explicitly tabular, add headers, enhance certain entries, etc. etc. Note that there are some apparent errors in the tables as well, but I'll fix them in a separate patch to make it easier to review/validate. Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: corbet@lwn.net Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: thgarnie@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-06x86/mm/doc: Clean up the x86-64 virtual memory layout descriptionsBaoquan He
In Documentation/x86/x86_64/mm.txt, the description of the x86-64 virtual memory layout has become a confusing hodgepodge of inconsistencies: - there's a hard to read mixture of 'TB' and 'bits' notation - the entries sometimes mention a size in the description and sometimes not - sometimes they list holes by address, sometimes only as an 'unused hole' line So make it all a coherent, readable, well organized description. Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: corbet@lwn.net Cc: linux-doc@vger.kernel.org Cc: thgarnie@google.com Link: http://lkml.kernel.org/r/20181006084327.27467-3-bhe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-28x86/intel_rdt: Use perf infrastructure for measurementsReinette Chatre
The success of a cache pseudo-locked region is measured using performance monitoring events that are programmed directly at the time the user requests a measurement. Modifying the performance event registers directly is not appropriate since it circumvents the in-kernel perf infrastructure that exists to manage these resources and provide resource arbitration to the performance monitoring hardware. The cache pseudo-locking measurements are modified to use the in-kernel perf infrastructure. Performance events are created and validated with the appropriate perf API. The performance counters are still read as directly as possible to avoid the additional cache hits. This is done safely by first ensuring with the perf API that the counters have been programmed correctly and only accessing the counters in an interrupt disabled section where they are not able to be moved. As part of the transition to the in-kernel perf infrastructure the L2 and L3 measurements are split into two separate measurements that can be triggered independently. This separation prevents additional cache misses incurred during the extra testing code used to decide if a L2 and/or L3 measurement should be made. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: peterz@infradead.org Cc: acme@kernel.org Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/fc24e728b446404f42c78573c506e98cd0599873.1537468643.git.reinette.chatre@intel.com
2018-09-10x86/doc: Fix Documentation/x86/earlyprintk.txtRandy Dunlap
Fix a few issues in Documentation/x86/earlyprintk.txt: - correct typos, punctuation, missing word, wrong word - change product name from Netchip to NetChip - expand where to add "earlyprintk=dbg" Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linux-doc@vger.kernel.org Cc: linux-usb@vger.kernel.org Link: http://lkml.kernel.org/r/d0c40ac3-7659-6374-dbda-23d3d2577f30@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-09Drop all 00-INDEX files from Documentation/Henrik Austad
This is a respin with a wider audience (all that get_maintainer returned) and I know this spams a *lot* of people. Not sure what would be the correct way, so my apologies for ruining your inbox. The 00-INDEX files are supposed to give a summary of all files present in a directory, but these files are horribly out of date and their usefulness is brought into question. Often a simple "ls" would reveal the same information as the filenames are generally quite descriptive as a short introduction to what the file covers (it should not surprise anyone what Documentation/sched/sched-design-CFS.txt covers) A few years back it was mentioned that these files were no longer really needed, and they have since then grown further out of date, so perhaps it is time to just throw them out. A short status yields the following _outdated_ 00-INDEX files, first counter is files listed in 00-INDEX but missing in the directory, last is files present but not listed in 00-INDEX. List of outdated 00-INDEX: Documentation: (4/10) Documentation/sysctl: (0/1) Documentation/timers: (1/0) Documentation/blockdev: (3/1) Documentation/w1/slaves: (0/1) Documentation/locking: (0/1) Documentation/devicetree: (0/5) Documentation/power: (1/1) Documentation/powerpc: (0/5) Documentation/arm: (1/0) Documentation/x86: (0/9) Documentation/x86/x86_64: (1/1) Documentation/scsi: (4/4) Documentation/filesystems: (2/9) Documentation/filesystems/nfs: (0/2) Documentation/cgroup-v1: (0/2) Documentation/kbuild: (0/4) Documentation/spi: (1/0) Documentation/virtual/kvm: (1/0) Documentation/scheduler: (0/2) Documentation/fb: (0/1) Documentation/block: (0/1) Documentation/networking: (6/37) Documentation/vm: (1/3) Then there are 364 subdirectories in Documentation/ with several files that are missing 00-INDEX alltogether (and another 120 with a single file and no 00-INDEX). I don't really have an opinion to whether or not we /should/ have 00-INDEX, but the above 00-INDEX should either be removed or be kept up to date. If we should keep the files, I can try to keep them updated, but I rather not if we just want to delete them anyway. As a starting point, remove all index-files and references to 00-INDEX and see where the discussion is going. Signed-off-by: Henrik Austad <henrik@austad.us> Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Just-do-it-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: [Almost everybody else] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-09-04x86/entry: Add STACKLEAK erasing the kernel stack at the end of syscallsAlexander Popov
The STACKLEAK feature (initially developed by PaX Team) has the following benefits: 1. Reduces the information that can be revealed through kernel stack leak bugs. The idea of erasing the thread stack at the end of syscalls is similar to CONFIG_PAGE_POISONING and memzero_explicit() in kernel crypto, which all comply with FDP_RIP.2 (Full Residual Information Protection) of the Common Criteria standard. 2. Blocks some uninitialized stack variable attacks (e.g. CVE-2017-17712, CVE-2010-2963). That kind of bugs should be killed by improving C compilers in future, which might take a long time. This commit introduces the code filling the used part of the kernel stack with a poison value before returning to userspace. Full STACKLEAK feature also contains the gcc plugin which comes in a separate commit. The STACKLEAK feature is ported from grsecurity/PaX. More information at: https://grsecurity.net/ https://pax.grsecurity.net/ This code is modified from Brad Spengler/PaX Team's code in the last public patch of grsecurity/PaX based on our understanding of the code. Changes or omissions from the original code are ours and don't reflect the original grsecurity/PaX code. Performance impact: Hardware: Intel Core i7-4770, 16 GB RAM Test #1: building the Linux kernel on a single core 0.91% slowdown Test #2: hackbench -s 4096 -l 2000 -g 15 -f 25 -P 4.2% slowdown So the STACKLEAK description in Kconfig includes: "The tradeoff is the performance impact: on a single CPU system kernel compilation sees a 1% slowdown, other systems and workloads may vary and you are advised to test this feature on your expected workload before deploying it". Signed-off-by: Alexander Popov <alex.popov@linux.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-08-13Merge branch 'x86-timers-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 timer updates from Thomas Gleixner: "Early TSC based time stamping to allow better boot time analysis. This comes with a general cleanup of the TSC calibration code which grew warts and duct taping over the years and removes 250 lines of code. Initiated and mostly implemented by Pavel with help from various folks" * 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) x86/kvmclock: Mark kvm_get_preset_lpj() as __init x86/tsc: Consolidate init code sched/clock: Disable interrupts when calling generic_sched_clock_init() timekeeping: Prevent false warning when persistent clock is not available sched/clock: Close a hole in sched_clock_init() x86/tsc: Make use of tsc_calibrate_cpu_early() x86/tsc: Split native_calibrate_cpu() into early and late parts sched/clock: Use static key for sched_clock_running sched/clock: Enable sched clock early sched/clock: Move sched clock initialization and merge with generic clock x86/tsc: Use TSC as sched clock early x86/tsc: Initialize cyc2ns when tsc frequency is determined x86/tsc: Calibrate tsc only once ARM/time: Remove read_boot_clock64() s390/time: Remove read_boot_clock64() timekeeping: Default boot time offset to local_clock() timekeeping: Replace read_boot_clock64() with read_persistent_wall_and_boot_offset() s390/time: Add read_persistent_wall_and_boot_offset() x86/xen/time: Output xen sched_clock time from 0 x86/xen/time: Initialize pv xen time in init_hypervisor_platform() ...
2018-08-13Merge branch 'x86-cache-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cache QoS (RDT/CAR) updates from Thomas Gleixner: "Add support for pseudo-locked cache regions. Cache Allocation Technology (CAT) allows on certain CPUs to isolate a region of cache and 'lock' it. Cache pseudo-locking builds on the fact that a CPU can still read and write data pre-allocated outside its current allocated area on cache hit. With cache pseudo-locking data can be preloaded into a reserved portion of cache that no application can fill, and from that point on will only serve cache hits. The cache pseudo-locked memory is made accessible to user space where an application can map it into its virtual address space and thus have a region of memory with reduced average read latency. The locking is not perfect and gets totally screwed by WBINDV and similar mechanisms, but it provides a reasonable enhancement for certain types of latency sensitive applications. The implementation extends the current CAT mechanism and provides a generally useful exclusive CAT mode on which it builds the extra pseude-locked regions" * 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits) x86/intel_rdt: Disable PMU access x86/intel_rdt: Fix possible circular lock dependency x86/intel_rdt: Make CPU information accessible for pseudo-locked regions x86/intel_rdt: Support restoration of subset of permissions x86/intel_rdt: Fix cleanup of plr structure on error x86/intel_rdt: Move pseudo_lock_region_clear() x86/intel_rdt: Limit C-states dynamically when pseudo-locking active x86/intel_rdt: Support L3 cache performance event of Broadwell x86/intel_rdt: More precise L2 hit/miss measurements x86/intel_rdt: Create character device exposing pseudo-locked region x86/intel_rdt: Create debugfs files for pseudo-locking testing x86/intel_rdt: Create resctrl debug area x86/intel_rdt: Ensure RDT cleanup on exit x86/intel_rdt: Resctrl files reflect pseudo-locked information x86/intel_rdt: Support creation/removal of pseudo-locked region x86/intel_rdt: Pseudo-lock region creation/removal core x86/intel_rdt: Discover supported platforms via prefetch disable bits x86/intel_rdt: Add utilities to test pseudo-locked region possibility x86/intel_rdt: Split resource group removal in two x86/intel_rdt: Enable entering of pseudo-locksetup mode ...
2018-07-20x86/tsc: Redefine notsc to behave as tsc=unstablePavel Tatashin
Currently, the notsc kernel parameter disables the use of the TSC by sched_clock(). However, this parameter does not prevent the kernel from accessing tsc in other places. The only rationale to boot with notsc is to avoid timing discrepancies on multi-socket systems where TSC are not properly synchronized, and thus exclude TSC from being used for time keeping. But that prevents using TSC as sched_clock() as well, which is not necessary as the core sched_clock() implementation can handle non synchronized TSC based sched clocks just fine. However, there is another method to solve the above problem: booting with tsc=unstable parameter. This parameter allows sched_clock() to use TSC and just excludes it from timekeeping. So there is no real reason to keep notsc, but for compatibility reasons the parameter has to stay. Make it behave like 'tsc=unstable' instead. [ tglx: Massaged changelog ] Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Cc: linux@armlinux.org.uk Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com Cc: john.stultz@linaro.org Cc: sboyd@codeaurora.org Cc: hpa@zytor.com Cc: peterz@infradead.org Cc: prarit@redhat.com Cc: feng.tang@intel.com Cc: pmladek@suse.com Cc: gnomes@lxorguk.ukuu.org.uk Cc: linux-s390@vger.kernel.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180719205545.16512-12-pasha.tatashin@oracle.com
2018-07-06x86/numa_emulation: Introduce uniform split capabilityDan Williams
The current NUMA emulation capabilities for splitting System RAM by a fixed size or by a set number of nodes may result in some nodes being larger than others. The implementation prioritizes establishing a minimum usable memory size over satisfying the requested number of NUMA nodes. Introduce a uniform split capability that evenly partitions each physical NUMA node into N emulated nodes. For example numa=fake=3U creates 6 emulated nodes total on a system that has 2 physical nodes. This capability is useful for debugging and evaluating platform memory-side-cache capabilities as described by the ACPI HMAT (see 5.2.27.5 Memory Side Cache Information Structure in ACPI 6.2a) Compare numa=fake=6 that results in only 5 nodes being created against numa=fake=3U which takes the 2 physical nodes and evenly divides them. numa=fake=6 available: 5 nodes (0-4) node 0 cpus: 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 node 0 size: 2648 MB node 0 free: 2443 MB node 1 cpus: 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 node 1 size: 2672 MB node 1 free: 2442 MB node 2 cpus: 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 node 2 size: 5291 MB node 2 free: 5278 MB node 3 cpus: 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 node 3 size: 2677 MB node 3 free: 2665 MB node 4 cpus: 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 node 4 size: 2676 MB node 4 free: 2663 MB node distances: node 0 1 2 3 4 0: 10 20 10 20 20 1: 20 10 20 10 10 2: 10 20 10 20 20 3: 20 10 20 10 10 4: 20 10 20 10 10 numa=fake=3U available: 6 nodes (0-5) node 0 cpus: 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 node 0 size: 2900 MB node 0 free: 2637 MB node 1 cpus: 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 node 1 size: 3023 MB node 1 free: 3012 MB node 2 cpus: 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 node 2 size: 2015 MB node 2 free: 2004 MB node 3 cpus: 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 node 3 size: 2704 MB node 3 free: 2522 MB node 4 cpus: 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 node 4 size: 2709 MB node 4 free: 2698 MB node 5 cpus: 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 node 5 size: 2612 MB node 5 free: 2601 MB node distances: node 0 1 2 3 4 5 0: 10 10 10 20 20 20 1: 10 10 10 20 20 20 2: 10 10 10 20 20 20 3: 20 20 20 10 10 10 4: 20 20 20 10 10 10 5: 20 20 20 10 10 10 Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/153089328617.27680.14930758266174305832.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-03x86/intel_rdt: Make CPU information accessible for pseudo-locked regionsReinette Chatre
When a resource group enters pseudo-locksetup mode it reflects that the platform supports cache pseudo-locking and the resource group is unused, ready to be used for a pseudo-locked region. Until it is set up as a pseudo-locked region the resource group is "locked down" such that no new tasks or cpus can be assigned to it. This is accomplished in a user visible way by making the cpus, cpus_list, and tasks resctrl files inaccassible (user cannot read from or write to these files). When the resource group changes to pseudo-locked mode it represents a cache pseudo-locked region. While not appropriate to make any changes to the cpus assigned to this region it is useful to make it easy for the user to see which cpus are associated with the pseudo-locked region. Modify the permissions of the cpus/cpus_list file when the resource group changes to pseudo-locked mode to support reading (not writing). The information presented to the user when reading the file are the cpus associated with the pseudo-locked region. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/12756b7963b6abc1bffe8fb560b87b75da827bd1.1530421961.git.reinette.chatre@intel.com
2018-06-24x86/intel_rdt: Limit C-states dynamically when pseudo-locking activeReinette Chatre
Deeper C-states impact cache content through shrinking of the cache or flushing entire cache to memory before reducing power to the cache. Deeper C-states will thus negatively impact the pseudo-locked regions. To avoid impacting pseudo-locked regions C-states are limited on pseudo-locked region creation so that cores associated with the pseudo-locked region are prevented from entering deeper C-states. This is accomplished by requesting a CPU latency target which will prevent the core from entering C6 across all supported platforms. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1ef4f99dd6ba12fa6fb44c5a1141e75f952b9cd9.1529706536.git.reinette.chatre@intel.com
2018-06-23x86/intel_rdt: Documentation for Cache Pseudo-LockingReinette Chatre
Add description of Cache Pseudo-Locking feature, its interface, as well as an example of its usage. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/6e118c15d2c254a27b8891783505cd1bb94a2b10.1529706536.git.reinette.chatre@intel.com
2018-06-23x86/intel_rdt: Document new mode, size, and bit_usageReinette Chatre
By default resource groups allow sharing of their cache allocations. There is nothing that prevents a resource group from configuring a cache allocation that overlaps with that of an existing resource group. To enable resource groups to specify that their cache allocations cannot be shared a resource group "mode" is introduced to support two possible modes: "shareable" and "exclusive". A "shareable" resource group allows sharing of its cache allocations, an "exclusive" resource group does not. A new resctrl file "mode" associated with each resource group is used to communicate its (the associated resource group's) mode setting and allow the mode to be changed. The new "mode" file as well as two other resctrl files, "bit_usage" and "size", are introduced in this series. Add documentation for the three new resctrl files as well as one example demonstrating their use. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/f03a3059ec40ae719be6f3fba9f446bb055e0064.1529706536.git.reinette.chatre@intel.com
2018-06-04Merge branch 'x86-cache-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cache resource controller updates from Thomas Gleixner: "An update for the Intel Resource Director Technolgy (RDT) which adds a feedback driven software controller to runtime adjust the bandwidth allocation MSRs. This makes the allocations more accurate and allows to use bandwidth values in understandable units (MB/s) instead of using percentage based allocations as the original, still available, interface. The software controller can be enabled with a new mount option for the resctrl filesystem" * 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidth x86/intel_rdt/mba_sc: Prepare for feedback loop x86/intel_rdt/mba_sc: Add schemata support x86/intel_rdt/mba_sc: Add initialization support x86/intel_rdt/mba_sc: Enable/disable MBA software controller x86/intel_rdt/mba_sc: Documentation for MBA software controller(mba_sc)
2018-05-28x86/pci-dma: remove the explicit nodac and allowdac optionChristoph Hellwig
This is something drivers should decide (modulo chipset quirks like for VIA), which as far as I can tell is how things have been handled for the last 15 years. Note that we keep the usedac option for now, as it is used in the wild to override the too generic VIA quirk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-28x86/pci-dma: remove the experimental forcesac boot optionChristoph Hellwig
Limiting the dma mask to avoid PCI (pre-PCIe) DAC cycles while paying the huge overhead of an IOMMU is rather pointless, and this seriously gets in the way of dma mapping work. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-28Documentation/x86: remove a stray reference to pci-nommu.cChristoph Hellwig
This is just the minimal workaround. The file is mostly either stale and/or duplicative of Documentation/admin-guide/kernel-parameters.txt, but that is much more work than I'm willing to do right now. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-19x86/intel_rdt/mba_sc: Documentation for MBA software controller(mba_sc)Vikas Shivappa
Add documentation about the feedback loop mechanism (MBA software controller) which lets the user specify the memory bandwidth allocation in MBps. This includes some changes to "schemata" formati with examples. Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: vikas.shivappa@intel.com Cc: ak@linux.intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1524263781-14267-2-git-send-email-vikas.shivappa@linux.intel.com
2018-04-15Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of fixes and updates for x86: - Address a swiotlb regression which was caused by the recent DMA rework and made driver fail because dma_direct_supported() returned false - Fix a signedness bug in the APIC ID validation which caused invalid APIC IDs to be detected as valid thereby bloating the CPU possible space. - Fix inconsisten config dependcy/select magic for the MFD_CS5535 driver. - Fix a corruption of the physical address space bits when encryption has reduced the address space and late cpuinfo updates overwrite the reduced bit information with the original value. - Dominiks syscall rework which consolidates the architecture specific syscall functions so all syscalls can be wrapped with the same macros. This allows to switch x86/64 to struct pt_regs based syscalls. Extend the clearing of user space controlled registers in the entry patch to the lower registers" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Fix signedness bug in APIC ID validity checks x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption x86/olpc: Fix inconsistent MFD_CS5535 configuration swiotlb: Use dma_direct_supported() for swiotlb_ops syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*() syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention syscalls/core, syscalls/x86: Clean up syscall stub naming convention syscalls/x86: Extend register clearing on syscall entry to lower registers syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64 syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32 syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y x86/syscalls: Don't pointlessly reload the system call number x86/mm: Fix documentation of module mapping range with 4-level paging x86/cpuid: Switch to 'static const' specifier
2018-04-12Merge branch 'WIP.x86/asm' into x86/urgent, because the topic is readyIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: kfifo: fix inaccurate comment tools/thermal: tmon: fix for segfault net: Spelling s/stucture/structure/ edd: don't spam log if no EDD information is present Documentation: Fix early-microcode.txt references after file rename tracing: Block comments should align the * on each line treewide: Fix typos in printk GenWQE: Fix a typo in two comments treewide: Align function definition open/close braces
2018-04-03x86/mm: Fix documentation of module mapping range with 4-level pagingKirill A. Shutemov
Commit: f5a40711fa58 ("x86/mm: Set MODULES_END to 0xffffffffff000000") changed MODULES_END back to a fixed value, but didn't update the documentation of memory layout for 4-level paging. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: f5a40711fa58 ("x86/mm: Set MODULES_END to 0xffffffffff000000") Link: http://lkml.kernel.org/r/20180402121025.10244-1-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-27Documentation: Fix early-microcode.txt references after file renameJaak Ristioja
The file Documentation/x86/early-microcode.txt was renamed to Documentation/x86/microcode.txt in 0e3258753f81, but it was still referenced by its old name in a three places: * Documentation/x86/00-INDEX * arch/x86/Kconfig * arch/x86/kernel/cpu/microcode/amd.c This commit updates these references accordingly. Fixes: 0e3258753f81 ("x86/microcode: Document the three loading methods") Signed-off-by: Jaak Ristioja <jaak@ristioja.ee> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-14Merge branch 'x86/urgent' into x86/mm to pick up dependenciesThomas Gleixner
2018-02-28Documentation, x86, resctrl: Make text and sample command matchLi RongQing
The text says "Move the cpus 4-7 over to p1", but the sample command writes to p0/cpus. Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: linux-doc@vger.kernel.org Link: https://lkml.kernel.org/r/1519712271-8802-1-git-send-email-lirongqing@baidu.com
2018-02-26Merge tag 'v4.16-rc3' into x86/mm, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-23x86/topology: Fix function name in documentationDou Liyang
topology_sibling_cpumask() is the correct thread-related topology function in the kernel: s/topology_sibling_mask/topology_sibling_cpumask Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: corbet@lwn.net Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/20180222084812.14497-1-douly.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16x86/mm: Allow to boot without LA57 if CONFIG_X86_5LEVEL=yKirill A. Shutemov
All pieces of the puzzle are in place and we can now allow to boot with CONFIG_X86_5LEVEL=y on a machine without LA57 support. Kernel will detect that LA57 is missing and fold p4d at runtime. Update the documentation and the Kconfig option description to reflect the change. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180214182542.69302-10-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-01Merge tag 'driver-core-4.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of "big" driver core patches for 4.16-rc1. The majority of the work here is in the firmware subsystem, with reworks to try to attempt to make the code easier to handle in the long run, but no functional change. There's also some tree-wide sysfs attribute fixups with lots of acks from the various subsystem maintainers, as well as a handful of other normal fixes and changes. And finally, some license cleanups for the driver core and sysfs code. All have been in linux-next for a while with no reported issues" * tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (48 commits) device property: Define type of PROPERTY_ENRTY_*() macros device property: Reuse property_entry_free_data() device property: Move property_entry_free_data() upper firmware: Fix up docs referring to FIRMWARE_IN_KERNEL firmware: Drop FIRMWARE_IN_KERNEL Kconfig option USB: serial: keyspan: Drop firmware Kconfig options sysfs: remove DEBUG defines sysfs: use SPDX identifiers drivers: base: add coredump driver ops sysfs: add attribute specification for /sysfs/devices/.../coredump test_firmware: fix missing unlock on error in config_num_requests_store() test_firmware: make local symbol test_fw_config static sysfs: turn WARN() into pr_warn() firmware: Fix a typo in fallback-mechanisms.rst treewide: Use DEVICE_ATTR_WO treewide: Use DEVICE_ATTR_RO treewide: Use DEVICE_ATTR_RW sysfs.h: Use octal permissions component: add debugfs support bus: simple-pm-bus: convert bool SIMPLE_PM_BUS to tristate ...
2018-01-29Merge branch 'x86-cache-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/cache updates from Thomas Gleixner: "A set of patches which add support for L2 cache partitioning to the Intel RDT facility" * 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Add command line parameter to control L2_CDP x86/intel_rdt: Enable L2 CDP in MSR IA32_L2_QOS_CFG x86/intel_rdt: Add two new resources for L2 Code and Data Prioritization (CDP) x86/intel_rdt: Enumerate L2 Code and Data Prioritization (CDP) feature x86/intel_rdt: Add L2CDP support in documentation x86/intel_rdt: Update documentation
2018-01-25firmware: Fix up docs referring to FIRMWARE_IN_KERNELBenjamin Gilbert
We've removed the option, so stop talking about it. Signed-off-by: Benjamin Gilbert <benjamin.gilbert@coreos.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-21Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti fixes from Thomas Gleixner: "A small set of fixes for the meltdown/spectre mitigations: - Make kprobes aware of retpolines to prevent probes in the retpoline thunks. - Make the machine check exception speculation protected. MCE used to issue an indirect call directly from the ASM entry code. Convert that to a direct call into a C-function and issue the indirect call from there so the compiler can add the retpoline protection, - Make the vmexit_fill_RSB() assembly less stupid - Fix a typo in the PTI documentation" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Optimize inline assembler for vmexit_fill_RSB x86/pti: Document fix wrong index kprobes/x86: Disable optimizing on the function jumps to indirect thunk kprobes/x86: Blacklist indirect thunk functions for kprobes retpoline: Introduce start/end markers of indirect thunk x86/mce: Make machine check speculation protected
2018-01-19x86/pti: Document fix wrong indexzhenwei.pi
In section <2. Runtime Cost>, fix wrong index. Signed-off-by: zhenwei.pi <zhenwei.pi@youruncloud.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: dave.hansen@linux.intel.com Link: https://lkml.kernel.org/r/1516237492-27739-1-git-send-email-zhenwei.pi@youruncloud.com
2018-01-18x86/intel_rdt: Add L2CDP support in documentationFenghua Yu
L2 and L3 Code and Data Prioritization (CDP) can be enabled separately. The existing mount parameter "cdp" is only for enabling L3 CDP and will be kept for backwards compability. Add a new mount parameter 'cdpl2' for L2 CDP. [ tglx: Made changelog readable ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: Vikas" <vikas.shivappa@intel.com> Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com> Cc: Reinette" <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1513810644-78015-3-git-send-email-fenghua.yu@intel.com
2018-01-18x86/intel_rdt: Update documentationFenghua Yu
With more flag bits in /proc/cpuinfo for RDT, it's better to classify the bits for readability. Some previously missing bits are added as well. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: Vikas" <vikas.shivappa@intel.com> Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com> Cc: Reinette" <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1513810644-78015-2-git-send-email-fenghua.yu@intel.com
2018-01-14Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti updates from Thomas Gleixner: "This contains: - a PTI bugfix to avoid setting reserved CR3 bits when PCID is disabled. This seems to cause issues on a virtual machine at least and is incorrect according to the AMD manual. - a PTI bugfix which disables the perf BTS facility if PTI is enabled. The BTS AUX buffer is not globally visible and causes the CPU to fault when the mapping disappears on switching CR3 to user space. A full fix which restores BTS on PTI is non trivial and will be worked on. - PTI bugfixes for EFI and trusted boot which make sure that the user space visible page table entries have the NX bit cleared - removal of dead code in the PTI pagetable setup functions - add PTI documentation - add a selftest for vsyscall to verify that the kernel actually implements what it advertises. - a sysfs interface to expose vulnerability and mitigation information so there is a coherent way for users to retrieve the status. - the initial spectre_v2 mitigations, aka retpoline: + The necessary ASM thunk and compiler support + The ASM variants of retpoline and the conversion of affected ASM code + Make LFENCE serializing on AMD so it can be used as speculation trap + The RSB fill after vmexit - initial objtool support for retpoline As I said in the status mail this is the most of the set of patches which should go into 4.15 except two straight forward patches still on hold: - the retpoline add on of LFENCE which waits for ACKs - the RSB fill after context switch Both should be ready to go early next week and with that we'll have covered the major holes of spectre_v2 and go back to normality" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits) x86,perf: Disable intel_bts when PTI security/Kconfig: Correct the Documentation reference for PTI x86/pti: Fix !PCID and sanitize defines selftests/x86: Add test_vsyscall x86/retpoline: Fill return stack buffer on vmexit x86/retpoline/irq32: Convert assembler indirect jumps x86/retpoline/checksum32: Convert assembler indirect jumps x86/retpoline/xen: Convert Xen hypercall indirect jumps x86/retpoline/hyperv: Convert assembler indirect jumps x86/retpoline/ftrace: Convert ftrace assembler indirect jumps x86/retpoline/entry: Convert entry assembler indirect jumps x86/retpoline/crypto: Convert crypto assembler indirect jumps x86/spectre: Add boot time option to select Spectre v2 mitigation x86/retpoline: Add initial retpoline support objtool: Allow alternatives to be ignored objtool: Detect jumps to retpoline thunks x86/pti: Make unpoison of pgd for trusted boot work for real x86/alternatives: Fix optimize_nops() checking sysfs/cpu: Fix typos in vulnerability documentation x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC ...
2018-01-06x86/Documentation: Add PTI descriptionDave Hansen
Add some details about how PTI works, what some of the downsides are, and how to debug it when things go wrong. Also document the kernel parameter: 'pti/nopti'. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Moritz Lipp <moritz.lipp@iaik.tugraz.at> Cc: Daniel Gruss <daniel.gruss@iaik.tugraz.at> Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at> Cc: Richard Fellner <richard.fellner@student.tugraz.at> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com> Cc: Andi Lutomirsky <luto@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180105174436.1BC6FA2B@viggo.jf.intel.com
2018-01-05Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more x86 pti fixes from Thomas Gleixner: "Another small stash of fixes for fallout from the PTI work: - Fix the modules vs. KASAN breakage which was caused by making MODULES_END depend of the fixmap size. That was done when the cpu entry area moved into the fixmap, but now that we have a separate map space for that this is causing more issues than it solves. - Use the proper cache flush methods for the debugstore buffers as they are mapped/unmapped during runtime and not statically mapped at boot time like the rest of the cpu entry area. - Make the map layout of the cpu_entry_area consistent for 4 and 5 level paging and fix the KASLR vaddr_end wreckage. - Use PER_CPU_EXPORT for per cpu variable and while at it unbreak nvidia gfx drivers by dropping the GPL export. The subject line of the commit tells it the other way around, but I noticed that too late. - Fix the ASM alternative macros so they can be used in the middle of an inline asm block. - Rename the BUG_CPU_INSECURE flag to BUG_CPU_MELTDOWN so the attack vector is properly identified. The Spectre mitigations will come with their own bug bits later" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/pti: Rename BUG_CPU_INSECURE to BUG_CPU_MELTDOWN x86/alternatives: Add missing '\n' at end of ALTERNATIVE inline asm x86/tlb: Drop the _GPL from the cpu_tlbstate export x86/events/intel/ds: Use the proper cache flush method for mapping ds buffers x86/kaslr: Fix the vaddr_end mess x86/mm: Map cpu_entry_area at the same place on 4/5 level x86/mm: Set MODULES_END to 0xffffffffff000000
2018-01-05x86/kaslr: Fix the vaddr_end messThomas Gleixner
vaddr_end for KASLR is only documented in the KASLR code itself and is adjusted depending on config options. So it's not surprising that a change of the memory layout causes KASLR to have the wrong vaddr_end. This can map arbitrary stuff into other areas causing hard to understand problems. Remove the whole ifdef magic and define the start of the cpu_entry_area to be the end of the KASLR vaddr range. Add documentation to that effect. Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") Reported-by: Benjamin Gilbert <benjamin.gilbert@coreos.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Benjamin Gilbert <benjamin.gilbert@coreos.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Garnier <thgarnie@google.com>, Cc: Alexander Kuleshov <kuleshovmail@gmail.com> Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801041320360.1771@nanos
2018-01-04x86/mm: Map cpu_entry_area at the same place on 4/5 levelThomas Gleixner
There is no reason for 4 and 5 level pagetables to have a different layout. It just makes determining vaddr_end for KASLR harder than necessary. Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Gilbert <benjamin.gilbert@coreos.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Garnier <thgarnie@google.com>, Cc: Alexander Kuleshov <kuleshovmail@gmail.com> Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801041320360.1771@nanos
2018-01-04x86/mm: Set MODULES_END to 0xffffffffff000000Andrey Ryabinin
Since f06bdd4001c2 ("x86/mm: Adapt MODULES_END based on fixmap section size") kasan_mem_to_shadow(MODULES_END) could be not aligned to a page boundary. So passing page unaligned address to kasan_populate_zero_shadow() have two possible effects: 1) It may leave one page hole in supposed to be populated area. After commit 21506525fb8d ("x86/kasan/64: Teach KASAN about the cpu_entry_area") that hole happens to be in the shadow covering fixmap area and leads to crash: BUG: unable to handle kernel paging request at fffffbffffe8ee04 RIP: 0010:check_memory_region+0x5c/0x190 Call Trace: <NMI> memcpy+0x1f/0x50 ghes_copy_tofrom_phys+0xab/0x180 ghes_read_estatus+0xfb/0x280 ghes_notify_nmi+0x2b2/0x410 nmi_handle+0x115/0x2c0 default_do_nmi+0x57/0x110 do_nmi+0xf8/0x150 end_repeat_nmi+0x1a/0x1e Note, the crash likely disappeared after commit 92a0f81d8957, which changed kasan_populate_zero_shadow() call the way it was before commit 21506525fb8d. 2) Attempt to load module near MODULES_END will fail, because __vmalloc_node_range() called from kasan_module_alloc() will hit the WARN_ON(!pte_none(*pte)) in the vmap_pte_range() and bail out with error. To fix this we need to make kasan_mem_to_shadow(MODULES_END) page aligned which means that MODULES_END should be 8*PAGE_SIZE aligned. The whole point of commit f06bdd4001c2 was to move MODULES_END down if NR_CPUS is big, so the cpu_entry_area takes a lot of space. But since 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") the cpu_entry_area is no longer in fixmap, so we could just set MODULES_END to a fixed 8*PAGE_SIZE aligned address. Fixes: f06bdd4001c2 ("x86/mm: Adapt MODULES_END based on fixmap section size") Reported-by: Jakub Kicinski <kubakici@wp.pl> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Cc: Andy Lutomirski <luto@kernel.org> Cc: Thomas Garnier <thgarnie@google.com> Link: https://lkml.kernel.org/r/20171228160620.23818-1-aryabinin@virtuozzo.com
2017-12-29Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 page table isolation updates from Thomas Gleixner: "This is the final set of enabling page table isolation on x86: - Infrastructure patches for handling the extra page tables. - Patches which map the various bits and pieces which are required to get in and out of user space into the user space visible page tables. - The required changes to have CR3 switching in the entry/exit code. - Optimizations for the CR3 switching along with documentation how the ASID/PCID mechanism works. - Updates to dump pagetables to cover the user space page tables for W+X scans and extra debugfs files to analyze both the kernel and the user space visible page tables The whole functionality is compile time controlled via a config switch and can be turned on/off on the command line as well" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) x86/ldt: Make the LDT mapping RO x86/mm/dump_pagetables: Allow dumping current pagetables x86/mm/dump_pagetables: Check user space page table for WX pages x86/mm/dump_pagetables: Add page table directory to the debugfs VFS hierarchy x86/mm/pti: Add Kconfig x86/dumpstack: Indicate in Oops whether PTI is configured and enabled x86/mm: Clarify the whole ASID/kernel PCID/user PCID naming x86/mm: Use INVPCID for __native_flush_tlb_single() x86/mm: Optimize RESTORE_CR3 x86/mm: Use/Fix PCID to optimize user/kernel switches x86/mm: Abstract switching CR3 x86/mm: Allow flushing for future ASID switches x86/pti: Map the vsyscall page if needed x86/pti: Put the LDT in its own PGD if PTI is on x86/mm/64: Make a full PGD-entry size hole in the memory map x86/events/intel/ds: Map debug buffers in cpu_entry_area x86/cpu_entry_area: Add debugstore entries to cpu_entry_area x86/mm/pti: Map ESPFIX into user space x86/mm/pti: Share entry text PMD x86/entry: Align entry text section to PMD boundary ...
2017-12-23x86/pti: Put the LDT in its own PGD if PTI is onAndy Lutomirski
With PTI enabled, the LDT must be mapped in the usermode tables somewhere. The LDT is per process, i.e. per mm. An earlier approach mapped the LDT on context switch into a fixmap area, but that's a big overhead and exhausted the fixmap space when NR_CPUS got big. Take advantage of the fact that there is an address space hole which provides a completely unused pgd. Use this pgd to manage per-mm LDT mappings. This has a down side: the LDT isn't (currently) randomized, and an attack that can write the LDT is instant root due to call gates (thanks, AMD, for leaving call gates in AMD64 but designing them wrong so they're only useful for exploits). This can be mitigated by making the LDT read-only or randomizing the mapping, either of which is strightforward on top of this patch. This will significantly slow down LDT users, but that shouldn't matter for important workloads -- the LDT is only used by DOSEMU(2), Wine, and very old libc implementations. [ tglx: Cleaned it up. ] Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Laight <David.Laight@aculab.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>