Commit Graph

246 Commits

Author SHA1 Message Date
Linus Torvalds
13e091b6dd Merge branch 'x86-timers-for-linus' of 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()
  ...
2018-08-13 18:28:19 -07:00
Linus Torvalds
30de24c7dd Merge branch 'x86-cache-for-linus' of 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
  ...
2018-08-13 16:01:46 -07:00
Pavel Tatashin
fe9af81e52 x86/tsc: Redefine notsc to behave as tsc=unstable
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
2018-07-20 00:02:39 +02:00
Dan Williams
cc9aec03e5 x86/numa_emulation: Introduce uniform split capability
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>
2018-07-06 18:48:58 +02:00
Reinette Chatre
33dc3e410a x86/intel_rdt: Make CPU information accessible for pseudo-locked regions
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
2018-07-03 08:38:40 +02:00
Reinette Chatre
6fc0de37f6 x86/intel_rdt: Limit C-states dynamically when pseudo-locking active
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
2018-06-24 15:35:48 +02:00
Reinette Chatre
e17e733070 x86/intel_rdt: Documentation for Cache Pseudo-Locking
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
2018-06-23 13:03:44 +02:00
Reinette Chatre
cba1aab84f x86/intel_rdt: Document new mode, size, and bit_usage
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
2018-06-23 13:03:40 +02:00
Linus Torvalds
ab20fd0013 Merge branch 'x86-cache-for-linus' of 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)
2018-06-04 21:34:39 -07:00
Christoph Hellwig
098afd9817 x86/pci-dma: remove the explicit nodac and allowdac option
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>
2018-05-28 12:48:21 +02:00
Christoph Hellwig
06e9552f5f x86/pci-dma: remove the experimental forcesac boot option
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>
2018-05-28 12:48:16 +02:00
Christoph Hellwig
84564d1c76 Documentation/x86: remove a stray reference to pci-nommu.c
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>
2018-05-28 12:48:12 +02:00
Vikas Shivappa
d6c64a4f49 x86/intel_rdt/mba_sc: Documentation for MBA software controller(mba_sc)
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
2018-05-19 13:16:42 +02:00
Linus Torvalds
9fb71c2f23 Merge branch 'x86-urgent-for-linus' of 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
2018-04-15 16:12:35 -07:00
Ingo Molnar
ef389b7346 Merge branch 'WIP.x86/asm' into x86/urgent, because the topic is ready
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-12 09:42:34 +02:00
Linus Torvalds
672a9c1069 Merge branch 'for-linus' of 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
2018-04-05 11:56:35 -07:00
Kirill A. Shutemov
9a3b7e5e65 x86/mm: Fix documentation of module mapping range with 4-level paging
Commit:

  f5a40711fa ("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: f5a40711fa ("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>
2018-04-03 12:59:02 +02:00
Jaak Ristioja
1897a9691e Documentation: Fix early-microcode.txt references after file rename
The file Documentation/x86/early-microcode.txt was renamed to
Documentation/x86/microcode.txt in 0e3258753f, 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: 0e3258753f ("x86/microcode: Document the three loading methods")
Signed-off-by: Jaak Ristioja <jaak@ristioja.ee>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-27 09:51:23 +02:00
Thomas Gleixner
745dd37f9d Merge branch 'x86/urgent' into x86/mm to pick up dependencies 2018-03-14 20:23:25 +01:00
Li RongQing
3000974616 Documentation, x86, resctrl: Make text and sample command match
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
2018-02-28 19:59:05 +01:00
Ingo Molnar
3f7df3efeb Linux 4.16-rc3
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Merge tag 'v4.16-rc3' into x86/mm, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-26 08:41:15 +01:00
Dou Liyang
0c52f7c549 x86/topology: Fix function name in documentation
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>
2018-02-23 08:40:12 +01:00
Kirill A. Shutemov
6657fca06e x86/mm: Allow to boot without LA57 if CONFIG_X86_5LEVEL=y
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>
2018-02-16 10:48:49 +01:00
Linus Torvalds
47fcc0360c Driver Core updates for 4.16-rc1
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.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.16-rc1' of 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
  ...
2018-02-01 10:00:28 -08:00
Linus Torvalds
f0b13428c9 Merge branch 'x86-cache-for-linus' of 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
2018-01-29 17:48:22 -08:00
Benjamin Gilbert
c508c46e6e firmware: Fix up docs referring to FIRMWARE_IN_KERNEL
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>
2018-01-25 12:46:30 +01:00
Linus Torvalds
5515114211 Merge branch 'x86-pti-for-linus' of 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
2018-01-21 10:48:35 -08:00
zhenwei.pi
98f0fceec7 x86/pti: Document fix wrong index
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
2018-01-19 16:31:29 +01:00
Fenghua Yu
aa55d5a4bd x86/intel_rdt: Add L2CDP support in documentation
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
2018-01-18 09:33:30 +01:00
Fenghua Yu
0ff8e080b1 x86/intel_rdt: Update documentation
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
2018-01-18 09:33:30 +01:00
Linus Torvalds
40548c6b6c Merge branch 'x86-pti-for-linus' of 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
  ...
2018-01-14 09:51:25 -08:00
Dave Hansen
01c9b17bf6 x86/Documentation: Add PTI description
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
2018-01-06 21:39:10 +01:00
Linus Torvalds
abb7099dbc Merge branch 'x86-pti-for-linus' of 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
2018-01-05 12:23:57 -08:00
Thomas Gleixner
1dddd25125 x86/kaslr: Fix the vaddr_end mess
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: 92a0f81d89 ("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
2018-01-05 00:39:57 +01:00
Thomas Gleixner
f207890481 x86/mm: Map cpu_entry_area at the same place on 4/5 level
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: 92a0f81d89 ("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
2018-01-04 23:04:57 +01:00
Andrey Ryabinin
f5a40711fa x86/mm: Set MODULES_END to 0xffffffffff000000
Since f06bdd4001 ("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
  21506525fb ("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 92a0f81d89, which
changed kasan_populate_zero_shadow() call the way it was before
commit 21506525fb.

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 f06bdd4001 was to move MODULES_END down if
NR_CPUS is big, so the cpu_entry_area takes a lot of space.
But since 92a0f81d89 ("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: f06bdd4001 ("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
2018-01-04 23:04:57 +01:00
Linus Torvalds
5aa90a8458 Merge branch 'x86-pti-for-linus' of 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
  ...
2017-12-29 17:02:49 -08:00
Andy Lutomirski
f55f0501cb x86/pti: Put the LDT in its own PGD if PTI is on
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>
2017-12-23 21:13:00 +01:00
Andy Lutomirski
9f449772a3 x86/mm/64: Make a full PGD-entry size hole in the memory map
Shrink vmalloc space from 16384TiB to 12800TiB to enlarge the hole starting
at 0xff90000000000000 to be a full PGD entry.

A subsequent patch will use this hole for the pagetable isolation LDT
alias.

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>
2017-12-23 21:13:00 +01:00
Linus Torvalds
caf9a82657 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 PTI preparatory patches from Thomas Gleixner:
 "Todays Advent calendar window contains twentyfour easy to digest
  patches. The original plan was to have twenty three matching the date,
  but a late fixup made that moot.

   - Move the cpu_entry_area mapping out of the fixmap into a separate
     address space. That's necessary because the fixmap becomes too big
     with NRCPUS=8192 and this caused already subtle and hard to
     diagnose failures.

     The top most patch is fresh from today and cures a brain slip of
     that tall grumpy german greybeard, who ignored the intricacies of
     32bit wraparounds.

   - Limit the number of CPUs on 32bit to 64. That's insane big already,
     but at least it's small enough to prevent address space issues with
     the cpu_entry_area map, which have been observed and debugged with
     the fixmap code

   - A few TLB flush fixes in various places plus documentation which of
     the TLB functions should be used for what.

   - Rename the SYSENTER stack to CPU_ENTRY_AREA stack as it is used for
     more than sysenter now and keeping the name makes backtraces
     confusing.

   - Prevent LDT inheritance on exec() by moving it to arch_dup_mmap(),
     which is only invoked on fork().

   - Make vysycall more robust.

   - A few fixes and cleanups of the debug_pagetables code. Check
     PAGE_PRESENT instead of checking the PTE for 0 and a cleanup of the
     C89 initialization of the address hint array which already was out
     of sync with the index enums.

   - Move the ESPFIX init to a different place to prepare for PTI.

   - Several code moves with no functional change to make PTI
     integration simpler and header files less convoluted.

   - Documentation fixes and clarifications"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit
  init: Invoke init_espfix_bsp() from mm_init()
  x86/cpu_entry_area: Move it out of the fixmap
  x86/cpu_entry_area: Move it to a separate unit
  x86/mm: Create asm/invpcid.h
  x86/mm: Put MMU to hardware ASID translation in one place
  x86/mm: Remove hard-coded ASID limit checks
  x86/mm: Move the CR3 construction functions to tlbflush.h
  x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what
  x86/mm: Remove superfluous barriers
  x86/mm: Use __flush_tlb_one() for kernel memory
  x86/microcode: Dont abuse the TLB-flush interface
  x86/uv: Use the right TLB-flush API
  x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack
  x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation
  x86/mm/64: Improve the memory map documentation
  x86/ldt: Prevent LDT inheritance on exec
  x86/ldt: Rework locking
  arch, mm: Allow arch_dup_mmap() to fail
  x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode
  ...
2017-12-23 11:53:04 -08:00
Thomas Gleixner
92a0f81d89 x86/cpu_entry_area: Move it out of the fixmap
Put the cpu_entry_area into a separate P4D entry. The fixmap gets too big
and 0-day already hit a case where the fixmap PTEs were cleared by
cleanup_highmap().

Aside of that the fixmap API is a pain as it's all backwards.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-22 20:13:05 +01:00
Peter Zijlstra
e8ffe96e59 x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-22 20:13:02 +01:00
Andy Lutomirski
5a7ccf4754 x86/mm/64: Improve the memory map documentation
The old docs had the vsyscall range wrong and were missing the fixmap.
Fix both.

There used to be 8 MB reserved for future vsyscalls, but that's long gone.

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>
2017-12-22 20:13:02 +01:00
Dave Hansen
c51ff2c7fc x86/pkeys: Update documentation about availability
Now that CPUs that implement Memory Protection Keys are publicly
available we can be a bit less oblique about where it is available.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171111001228.DC748A10@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-21 09:34:52 +01:00
Linus Torvalds
3643b7e05b Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cache resource updates from Thomas Gleixner:
 "This update provides updates to RDT:

  - A diagnostic framework for the Resource Director Technology (RDT)
    user interface (sysfs). The failure modes of the user interface are
    hard to diagnose from the error codes. An extra last command status
    file provides now sensible textual information about the failure so
    its simpler to use.

  - A few minor cleanups and updates in the RDT code"

* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel_rdt: Fix a silent failure when writing zero value schemata
  x86/intel_rdt: Fix potential deadlock during resctrl mount
  x86/intel_rdt: Fix potential deadlock during resctrl unmount
  x86/intel_rdt: Initialize bitmask of shareable resource if CDP enabled
  x86/intel_rdt: Remove redundant assignment
  x86/intel_rdt/cqm: Make integer rmid_limbo_count static
  x86/intel_rdt: Add documentation for "info/last_cmd_status"
  x86/intel_rdt: Add diagnostics when making directories
  x86/intel_rdt: Add diagnostics when writing the cpus file
  x86/intel_rdt: Add diagnostics when writing the tasks file
  x86/intel_rdt: Add diagnostics when writing the schemata file
  x86/intel_rdt: Add framework for better RDT UI diagnostics
2017-11-13 19:05:19 -08:00
Brijesh Singh
33e63acc11 Documentation/x86: Add AMD Secure Encrypted Virtualization (SEV) description
Update the AMD memory encryption document describing the Secure Encrypted
Virtualization (SEV) feature.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: kvm@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20171020143059.3291-2-brijesh.singh@amd.com
2017-11-07 15:35:54 +01:00
Ingo Molnar
75ec4eb3dc Merge branch 'x86/mm' into x86/asm, to pick up pending changes
Concentrate x86 MM and asm related changes into a single super-topic,
in preparation for larger changes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-06 09:49:28 +01:00
Andrey Ryabinin
12a8cc7fcf x86/kasan: Use the same shadow offset for 4- and 5-level paging
We are going to support boot-time switching between 4- and 5-level
paging. For KASAN it means we cannot have different KASAN_SHADOW_OFFSET
for different paging modes: the constant is passed to gcc to generate
code and cannot be changed at runtime.

This patch changes KASAN code to use 0xdffffc0000000000 as shadow offset
for both 4- and 5-level paging.

For 5-level paging it means that shadow memory region is not aligned to
PGD boundary anymore and we have to handle unaligned parts of the region
properly.

In addition, we have to exclude paravirt code from KASAN instrumentation
as we now use set_pgd() before KASAN is fully ready.

[kirill.shutemov@linux.intel.com: clenaup, changelog message]
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
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/20170929140821.37654-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-20 13:07:09 +02:00
Josh Poimboeuf
11af847446 x86/unwind: Rename unwinder config options to 'CONFIG_UNWINDER_*'
Rename the unwinder config options from:

  CONFIG_ORC_UNWINDER
  CONFIG_FRAME_POINTER_UNWINDER
  CONFIG_GUESS_UNWINDER

to:

  CONFIG_UNWINDER_ORC
  CONFIG_UNWINDER_FRAME_POINTER
  CONFIG_UNWINDER_GUESS

... in order to give them a more logical config namespace.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/73972fc7e2762e91912c6b9584582703d6f1b8cc.1507924831.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-14 10:12:12 +02:00
Tony Luck
165d3ad884 x86/intel_rdt: Add documentation for "info/last_cmd_status"
New file in the "info" directory helps diagnose what went wrong
when using the /sys/fs/resctrl file system

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vikas Shivappa <vikas.shivappa@intel.com>
Cc: Boris Petkov <bp@suse.de>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/387e78e444582403c2454479e576caf5721a363f.1506382469.git.tony.luck@intel.com
2017-09-27 12:10:11 +02:00