We are about to commit complex rework of various x86 entry code details - create
a unified base tree (with FPU commits included) before doing that.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
do_clear_cpu_cap() allocates a bitmap to keep track of disabled feature
dependencies. That bitmap is sized NCAPINTS * BITS_PER_INIT. The possible
'features' which can be handed in are larger than this, because after the
capabilities the bug 'feature' bits occupy another 32bit. Not really
obvious...
So clearing any of the misfeature bits, as 32bit does for the F00F bug,
accesses that bitmap out of bounds thereby corrupting the stack.
Size the bitmap proper and add a sanity check to catch accidental out of
bound access.
Fixes: 0b00de857a ("x86/cpuid: Add generic table for CPUID dependencies")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20171018022023.GA12058@yexl-desktop
With a followon patch we want to make clearcpuid affect the XSAVE
configuration. But xsave is currently initialized before arguments
are parsed. Move the clearcpuid= parsing into the special
early xsave argument parsing code.
Since clearcpuid= contains a = we need to keep the old __setup
around as a dummy, otherwise it would end up as a environment
variable in init's environment.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171013215645.23166-4-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some CPUID features depend on other features. Currently it's
possible to to clear dependent features, but not clear the base features,
which can cause various interesting problems.
This patch implements a generic table to describe dependencies
between CPUID features, to be used by all code that clears
CPUID.
Some subsystems (like XSAVE) had an own implementation of this,
but it's better to do it all in a single place for everyone.
Then clear_cpu_cap and setup_clear_cpu_cap always look up
this table and clear all dependencies too.
This is intended to be a practical table: only for features
that make sense to clear. If someone for example clears FPU,
or other features that are essentially part of the required
base feature set, not much is going to work. Handling
that is right now out of scope. We're only handling
features which can be usefully cleared.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jonathan McDowell <noodles@earth.li>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171013215645.23166-3-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Ingo Molnar:
"A landry list of fixes:
- fix reboot breakage on some PCID-enabled system
- fix crashes/hangs on some PCID-enabled systems
- fix microcode loading on certain older CPUs
- various unwinder fixes
- extend an APIC quirk to more hardware systems and disable APIC
related warning on virtualized systems
- various Hyper-V fixes
- a macro definition robustness fix
- remove jprobes IRQ disabling
- various mem-encryption fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/microcode: Do the family check first
x86/mm: Flush more aggressively in lazy TLB mode
x86/apic: Update TSC_DEADLINE quirk with additional SKX stepping
x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on hypervisors
x86/mm: Disable various instrumentations of mm/mem_encrypt.c and mm/tlb.c
x86/hyperv: Fix hypercalls with extended CPU ranges for TLB flushing
x86/hyperv: Don't use percpu areas for pcpu_flush/pcpu_flush_ex structures
x86/hyperv: Clear vCPU banks between calls to avoid flushing unneeded vCPUs
x86/unwind: Disable unwinder warnings on 32-bit
x86/unwind: Align stack pointer in unwinder dump
x86/unwind: Use MSB for frame pointer encoding on 32-bit
x86/unwind: Fix dereference of untrusted pointer
x86/alternatives: Fix alt_max_short macro to really be a max()
x86/mm/64: Fix reboot interaction with CR4.PCIDE
kprobes/x86: Remove IRQ disabling from jprobe handlers
kprobes/x86: Set up frame pointer in kprobe trampoline
Commands are given to the resctrl file system by making/removing
directories, or by writing to files. When something goes wrong
the user is generally left wondering why they got:
bash: echo: write error: Invalid argument
Add a new file "last_cmd_status" to the "info" directory that
will give the user some better clues on what went wrong.
Provide functions to clear and update last_cmd_status which
check that we hold the rdtgroup_mutex.
[ tglx: Made last_cmd_status static and folded back the hunk from patch 3
which replaces the open coded access to last_cmd_status with the
accessor function ]
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/edc4e0e9741eee89bba569f0021b1b2662fd9508.1506382469.git.tony.luck@intel.com
cpu_init() is weird: it's called rather late (after early
identification and after most MMU state is initialized) on the boot
CPU but is called extremely early (before identification) on secondary
CPUs. It's called just late enough on the boot CPU that its CR4 value
isn't propagated to mmu_cr4_features.
Even if we put CR4.PCIDE into mmu_cr4_features, we'd hit two
problems. First, we'd crash in the trampoline code. That's
fixable, and I tried that. It turns out that mmu_cr4_features is
totally ignored by secondary_start_64(), though, so even with the
trampoline code fixed, it wouldn't help.
This means that we don't currently have CR4.PCIDE reliably initialized
before we start playing with cpu_tlbstate. This is very fragile and
tends to cause boot failures if I make even small changes to the TLB
handling code.
Make it more robust: initialize CR4.PCIDE earlier on the boot CPU
and propagate it to secondary CPUs in start_secondary().
( Yes, this is ugly. I think we should have improved mmu_cr4_features
to actually control CR4 during secondary bootup, but that would be
fairly intrusive at this stage. )
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reported-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Tested-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Fixes: 660da7c922 ("x86/mm: Enable CR4.PCIDE on supported systems")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 platform updates from Ingo Molnar:
"The main changes include various Hyper-V optimizations such as faster
hypercalls and faster/better TLB flushes - and there's also some
Intel-MID cleanups"
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tracing/hyper-v: Trace hyperv_mmu_flush_tlb_others()
x86/hyper-v: Support extended CPU ranges for TLB flush hypercalls
x86/platform/intel-mid: Make several arrays static, to make code smaller
MAINTAINERS: Add missed file for Hyper-V
x86/hyper-v: Use hypercall for remote TLB flush
hyper-v: Globalize vp_index
x86/hyper-v: Implement rep hypercalls
hyper-v: Use fast hypercall for HVCALL_SIGNAL_EVENT
x86/hyper-v: Introduce fast hypercall implementation
x86/hyper-v: Make hv_do_hypercall() inline
x86/hyper-v: Include hyperv/ only when CONFIG_HYPERV is set
x86/platform/intel-mid: Make 'bt_sfi_data' const
x86/platform/intel-mid: Make IRQ allocation a bit more flexible
x86/platform/intel-mid: Group timers callbacks together
While debugging a problem, I thought that using
cr4_set_bits_and_update_boot() to restore CR4.PCIDE would be
helpful. It turns out to be counterproductive.
Add a comment documenting how this works.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When Linux brings a CPU down and back up, it switches to init_mm and then
loads swapper_pg_dir into CR3. With PCID enabled, this has the side effect
of masking off the ASID bits in CR3.
This can result in some confusion in the TLB handling code. If we
bring a CPU down and back up with any ASID other than 0, we end up
with the wrong ASID active on the CPU after resume. This could
cause our internal state to become corrupt, although major
corruption is unlikely because init_mm doesn't have any user pages.
More obviously, if CONFIG_DEBUG_VM=y, we'll trip over an assertion
in the next context switch. The result of *that* is a failure to
resume from suspend with probability 1 - 1/6^(cpus-1).
Fix it by reinitializing cpu_tlbstate on resume and CPU bringup.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Jiri Kosina <jikos@kernel.org>
Fixes: 10af6235e0 ("x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull char/misc driver updates from Greg KH:
"Here is the big char/misc driver update for 4.14-rc1.
Lots of different stuff in here, it's been an active development cycle
for some reason. Highlights are:
- updated binder driver, this brings binder up to date with what
shipped in the Android O release, plus some more changes that
happened since then that are in the Android development trees.
- coresight updates and fixes
- mux driver file renames to be a bit "nicer"
- intel_th driver updates
- normal set of hyper-v updates and changes
- small fpga subsystem and driver updates
- lots of const code changes all over the driver trees
- extcon driver updates
- fmc driver subsystem upadates
- w1 subsystem minor reworks and new features and drivers added
- spmi driver updates
Plus a smattering of other minor driver updates and fixes.
All of these have been in linux-next with no reported issues for a
while"
* tag 'char-misc-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (244 commits)
ANDROID: binder: don't queue async transactions to thread.
ANDROID: binder: don't enqueue death notifications to thread todo.
ANDROID: binder: Don't BUG_ON(!spin_is_locked()).
ANDROID: binder: Add BINDER_GET_NODE_DEBUG_INFO ioctl
ANDROID: binder: push new transactions to waiting threads.
ANDROID: binder: remove proc waitqueue
android: binder: Add page usage in binder stats
android: binder: fixup crash introduced by moving buffer hdr
drivers: w1: add hwmon temp support for w1_therm
drivers: w1: refactor w1_slave_show to make the temp reading functionality separate
drivers: w1: add hwmon support structures
eeprom: idt_89hpesx: Support both ACPI and OF probing
mcb: Fix an error handling path in 'chameleon_parse_cells()'
MCB: add support for SC31 to mcb-lpc
mux: make device_type const
char: virtio: constify attribute_group structures.
Documentation/ABI: document the nvmem sysfs files
lkdtm: fix spelling mistake: "incremeted" -> "incremented"
perf: cs-etm: Fix ETMv4 CONFIGR entry in perf.data file
nvmem: include linux/err.h from header
...
Pull x86 apic updates from Thomas Gleixner:
"This update provides:
- Cleanup of the IDT management including the removal of the extra
tracing IDT. A first step to cleanup the vector management code.
- The removal of the paravirt op adjust_exception_frame. This is a
XEN specific issue, but merged through this branch to avoid nasty
merge collisions
- Prevent dmesg spam about the TSC DEADLINE bug, when the CPU has
disabled the TSC DEADLINE timer in CPUID.
- Adjust a debug message in the ioapic code to print out the
information correctly"
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
x86/idt: Fix the X86_TRAP_BP gate
x86/xen: Get rid of paravirt op adjust_exception_frame
x86/eisa: Add missing include
x86/idt: Remove superfluous ALIGNment
x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature
x86/idt: Remove the tracing IDT leftovers
x86/idt: Hide set_intr_gate()
x86/idt: Simplify alloc_intr_gate()
x86/idt: Deinline setup functions
x86/idt: Remove unused functions/inlines
x86/idt: Move interrupt gate initialization to IDT code
x86/idt: Move APIC gate initialization to tables
x86/idt: Move regular trap init to tables
x86/idt: Move IST stack based traps to table init
x86/idt: Move debug stack init to table based
x86/idt: Switch early trap init to IDT tables
x86/idt: Prepare for table based init
x86/idt: Move early IDT setup out of 32-bit asm
x86/idt: Move early IDT handler setup to IDT code
x86/idt: Consolidate IDT invalidation
...
Pull x86 cache quality monitoring update from Thomas Gleixner:
"This update provides a complete rewrite of the Cache Quality
Monitoring (CQM) facility.
The existing CQM support was duct taped into perf with a lot of issues
and the attempts to fix those turned out to be incomplete and
horrible.
After lengthy discussions it was decided to integrate the CQM support
into the Resource Director Technology (RDT) facility, which is the
obvious choise as in hardware CQM is part of RDT. This allowed to add
Memory Bandwidth Monitoring support on top.
As a result the mechanisms for allocating cache/memory bandwidth and
the corresponding monitoring mechanisms are integrated into a single
management facility with a consistent user interface"
* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
x86/intel_rdt: Turn off most RDT features on Skylake
x86/intel_rdt: Add command line options for resource director technology
x86/intel_rdt: Move special case code for Haswell to a quirk function
x86/intel_rdt: Remove redundant ternary operator on return
x86/intel_rdt/cqm: Improve limbo list processing
x86/intel_rdt/mbm: Fix MBM overflow handler during CPU hotplug
x86/intel_rdt: Modify the intel_pqr_state for better performance
x86/intel_rdt/cqm: Clear the default RMID during hotcpu
x86/intel_rdt: Show bitmask of shareable resource with other executing units
x86/intel_rdt/mbm: Handle counter overflow
x86/intel_rdt/mbm: Add mbm counter initialization
x86/intel_rdt/mbm: Basic counting of MBM events (total and local)
x86/intel_rdt/cqm: Add CPU hotplug support
x86/intel_rdt/cqm: Add sched_in support
x86/intel_rdt: Introduce rdt_enable_key for scheduling
x86/intel_rdt/cqm: Add mount,umount support
x86/intel_rdt/cqm: Add rmdir support
x86/intel_rdt: Separate the ctrl bits from rmdir
x86/intel_rdt/cqm: Add mon_data
x86/intel_rdt: Prepare for RDT monitor data support
...
Pull x86 mm changes from Ingo Molnar:
"PCID support, 5-level paging support, Secure Memory Encryption support
The main changes in this cycle are support for three new, complex
hardware features of x86 CPUs:
- Add 5-level paging support, which is a new hardware feature on
upcoming Intel CPUs allowing up to 128 PB of virtual address space
and 4 PB of physical RAM space - a 512-fold increase over the old
limits. (Supercomputers of the future forecasting hurricanes on an
ever warming planet can certainly make good use of more RAM.)
Many of the necessary changes went upstream in previous cycles,
v4.14 is the first kernel that can enable 5-level paging.
This feature is activated via CONFIG_X86_5LEVEL=y - disabled by
default.
(By Kirill A. Shutemov)
- Add 'encrypted memory' support, which is a new hardware feature on
upcoming AMD CPUs ('Secure Memory Encryption', SME) allowing system
RAM to be encrypted and decrypted (mostly) transparently by the
CPU, with a little help from the kernel to transition to/from
encrypted RAM. Such RAM should be more secure against various
attacks like RAM access via the memory bus and should make the
radio signature of memory bus traffic harder to intercept (and
decrypt) as well.
This feature is activated via CONFIG_AMD_MEM_ENCRYPT=y - disabled
by default.
(By Tom Lendacky)
- Enable PCID optimized TLB flushing on newer Intel CPUs: PCID is a
hardware feature that attaches an address space tag to TLB entries
and thus allows to skip TLB flushing in many cases, even if we
switch mm's.
(By Andy Lutomirski)
All three of these features were in the works for a long time, and
it's coincidence of the three independent development paths that they
are all enabled in v4.14 at once"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (65 commits)
x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)
x86/mm: Use pr_cont() in dump_pagetable()
x86/mm: Fix SME encryption stack ptr handling
kvm/x86: Avoid clearing the C-bit in rsvd_bits()
x86/CPU: Align CR3 defines
x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages
acpi, x86/mm: Remove encryption mask from ACPI page protection type
x86/mm, kexec: Fix memory corruption with SME on successive kexecs
x86/mm/pkeys: Fix typo in Documentation/x86/protection-keys.txt
x86/mm/dump_pagetables: Speed up page tables dump for CONFIG_KASAN=y
x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID
x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y
x86/mm: Allow userspace have mappings above 47-bit
x86/mm: Prepare to expose larger address space to userspace
x86/mpx: Do not allow MPX if we have mappings above 47-bit
x86/mm: Rename tasksize_32bit/64bit to task_size_32bit/64bit()
x86/xen: Redefine XEN_ELFNOTE_INIT_P2M using PUD_SIZE * PTRS_PER_PUD
x86/mm/dump_pagetables: Fix printout of p4d level
x86/mm/dump_pagetables: Generalize address normalization
x86/boot: Fix memremap() related build failure
...
Pull x86 microcode loading updates from Ingo Molnar:
"Update documentation, improve robustness and fix a memory leak"
* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/microcode/intel: Improve microcode patches saving flow
x86/microcode: Document the three loading methods
x86/microcode/AMD: Free unneeded patch before exit from update_cache()
Pull x86 cpuid updates from Ingo Molnar:
"AMD F17h related updates"
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu/amd: Hide unused legacy_fixup_core_id() function
x86/cpu/amd: Derive L3 shared_cpu_map from cpu_llc_shared_mask
x86/cpu/amd: Limit cpu_core_id fixup to families older than F17h
Pull RAS fix from Ingo Molnar:
"A single change fixing SMCA bank initialization on systems that don't
have CPU0 enabled"
* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce/AMD: Allow any CPU to initialize the smca_banks array
Avoid potentially dereferencing a NULL pointer when saving a microcode
patch for early loading on the application processors.
While at it, drop the IS_ERR() checking in favor of simpler, NULL-ptr
checks which are sufficient and rename __alloc_microcode_buf() to
memdup_patch() to more precisely denote what it does.
No functionality change.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825100456.n236w3jebteokfd6@pd.tnic
Pull x86 fixes from Thomas Gleixner:
"Another pile of small fixes and updates for x86:
- Plug a hole in the SMAP implementation which misses to clear AC on
NMI entry
- Fix the norandmaps/ADDR_NO_RANDOMIZE logic so the command line
parameter works correctly again
- Use the proper accessor in the startup64 code for next_early_pgt to
prevent accessing of invalid addresses and faulting in the early
boot code.
- Prevent CPU hotplug lock recursion in the MTRR code
- Unbreak CPU0 hotplugging
- Rename overly long CPUID bits which got introduced in this cycle
- Two commits which mark data 'const' and restrict the scope of data
and functions to file scope by making them 'static'"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Constify attribute_group structures
x86/boot/64/clang: Use fixup_pointer() to access 'next_early_pgt'
x86/elf: Remove the unnecessary ADDR_NO_RANDOMIZE checks
x86: Fix norandmaps/ADDR_NO_RANDOMIZE
x86/mtrr: Prevent CPU hotplug lock recursion
x86: Mark various structures and functions as 'static'
x86/cpufeature, kvm/svm: Rename (shorten) the new "virtualized VMSAVE/VMLOAD" CPUID flag
x86/smpboot: Unbreak CPU0 hotplug
x86/asm/64: Clear AC on NMI entries
