Linus Torvalds
958f338e96
Merge branch 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
...
Merge L1 Terminal Fault fixes from Thomas Gleixner:
"L1TF, aka L1 Terminal Fault, is yet another speculative hardware
engineering trainwreck. It's a hardware vulnerability which allows
unprivileged speculative access to data which is available in the
Level 1 Data Cache when the page table entry controlling the virtual
address, which is used for the access, has the Present bit cleared or
other reserved bits set.
If an instruction accesses a virtual address for which the relevant
page table entry (PTE) has the Present bit cleared or other reserved
bits set, then speculative execution ignores the invalid PTE and loads
the referenced data if it is present in the Level 1 Data Cache, as if
the page referenced by the address bits in the PTE was still present
and accessible.
While this is a purely speculative mechanism and the instruction will
raise a page fault when it is retired eventually, the pure act of
loading the data and making it available to other speculative
instructions opens up the opportunity for side channel attacks to
unprivileged malicious code, similar to the Meltdown attack.
While Meltdown breaks the user space to kernel space protection, L1TF
allows to attack any physical memory address in the system and the
attack works across all protection domains. It allows an attack of SGX
and also works from inside virtual machines because the speculation
bypasses the extended page table (EPT) protection mechanism.
The assoicated CVEs are: CVE-2018-3615, CVE-2018-3620, CVE-2018-3646
The mitigations provided by this pull request include:
- Host side protection by inverting the upper address bits of a non
present page table entry so the entry points to uncacheable memory.
- Hypervisor protection by flushing L1 Data Cache on VMENTER.
- SMT (HyperThreading) control knobs, which allow to 'turn off' SMT
by offlining the sibling CPU threads. The knobs are available on
the kernel command line and at runtime via sysfs
- Control knobs for the hypervisor mitigation, related to L1D flush
and SMT control. The knobs are available on the kernel command line
and at runtime via sysfs
- Extensive documentation about L1TF including various degrees of
mitigations.
Thanks to all people who have contributed to this in various ways -
patches, review, testing, backporting - and the fruitful, sometimes
heated, but at the end constructive discussions.
There is work in progress to provide other forms of mitigations, which
might be less horrible performance wise for a particular kind of
workloads, but this is not yet ready for consumption due to their
complexity and limitations"
* 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
x86/microcode: Allow late microcode loading with SMT disabled
tools headers: Synchronise x86 cpufeatures.h for L1TF additions
x86/mm/kmmio: Make the tracer robust against L1TF
x86/mm/pat: Make set_memory_np() L1TF safe
x86/speculation/l1tf: Make pmd/pud_mknotpresent() invert
x86/speculation/l1tf: Invert all not present mappings
cpu/hotplug: Fix SMT supported evaluation
KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry
x86/speculation: Use ARCH_CAPABILITIES to skip L1D flush on vmentry
x86/speculation: Simplify sysfs report of VMX L1TF vulnerability
Documentation/l1tf: Remove Yonah processors from not vulnerable list
x86/KVM/VMX: Don't set l1tf_flush_l1d from vmx_handle_external_intr()
x86/irq: Let interrupt handlers set kvm_cpu_l1tf_flush_l1d
x86: Don't include linux/irq.h from asm/hardirq.h
x86/KVM/VMX: Introduce per-host-cpu analogue of l1tf_flush_l1d
x86/irq: Demote irq_cpustat_t::__softirq_pending to u16
x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush()
x86/KVM/VMX: Replace 'vmx_l1d_flush_always' with 'vmx_l1d_flush_cond'
x86/KVM/VMX: Don't set l1tf_flush_l1d to true from vmx_l1d_flush()
cpu/hotplug: detect SMT disabled by BIOS
...
2018-08-14 09:46:06 -07:00
..
bitops
locking/atomics, asm-generic/bitops/lock.h: Rewrite using atomic_fetch_*()
2018-06-21 12:52:12 +02:00
4level-fixup.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
5level-fixup.h
x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable
2018-02-14 13:11:14 +01:00
asm-offsets.h
asm-generic: Add common asm-offsets.h
2015-06-23 13:35:49 +09:00
asm-prototypes.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
atomic-instrumented.h
locking/atomics: Instrument cmpxchg_double*()
2018-07-25 11:53:59 +02:00
atomic-long.h
locking/mutex: Optimize __mutex_trylock_fast()
2018-05-04 10:02:39 +02:00
atomic.h
atomics/treewide: Make unconditional inc/dec ops optional
2018-06-21 14:25:24 +02:00
atomic64.h
atomics/treewide: Make conditional inc/dec ops optional
2018-06-21 14:25:24 +02:00
audit_change_attr.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
audit_dir_write.h
audit: Avoid build failures on systems without renameat
2018-01-30 19:07:54 -08:00
audit_read.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
audit_signal.h
audit_write.h
audit/stable-4.15 PR 20171113
2017-11-15 13:28:48 -08:00
barrier.h
locking/barriers: Introduce smp_cond_load_relaxed() and atomic_cond_read_relaxed()
2018-04-27 09:48:44 +02:00
bitops.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
bitsperlong.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
bug.h
bug.h: work around GCC PR82365 in BUG()
2018-02-21 15:35:43 -08:00
bugs.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
cache.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
cacheflush.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
checksum.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
cmpxchg-local.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
cmpxchg.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
compat.h
time: Add an asm-generic/compat.h file
2018-04-19 13:28:51 +02:00
current.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
delay.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
device.h
div64.h
A relatively calm cycle for the docs tree again.
2017-11-13 08:25:06 -08:00
dma-contiguous.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
dma-mapping.h
dma-mapping: provide a generic dma-noncoherent implementation
2018-05-19 08:46:12 +02:00
dma.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
early_ioremap.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
emergency-restart.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
error-injection.h
error-injection: Add injectable error types
2018-01-12 17:33:38 -08:00
exec.h
mn10300: Remove the architecture
2018-03-09 23:19:56 +01:00
export.h
export.h: remove code for prefixing symbols with underscore
2018-05-17 22:44:57 +09:00
extable.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
fb.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
fixmap.h
asm-generic: Fix local variable shadow in __set_fixmap_offset
2016-02-16 15:10:44 +00:00
ftrace.h
futex.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
getorder.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
gpio.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
hardirq.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
hugetlb.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
hw_irq.h
ide_iops.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
int-ll64.h
int-ll64.h: define u{8,16,32,64} and s{8,16,32,64} based on uapi header
2018-06-07 17:34:38 -07:00
io.h
asm-generic fixes for v4.17-rc1
2018-04-12 09:15:48 -07:00
ioctl.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
iomap.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
irq.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
irq_regs.h
irq_work.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
irqflags.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
kdebug.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
kmap_types.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
kprobes.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
kvm_para.h
KVM: Introduce paravirtualization hints and KVM_HINTS_DEDICATED
2018-03-06 18:40:44 +01:00
linkage.h
local.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
local64.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
mcs_spinlock.h
memory_model.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
mm-arch-hooks.h
mm: clean up per architecture MM hook header files
2015-07-17 16:39:53 -07:00
mm_hooks.h
arch, mm: Allow arch_dup_mmap() to fail
2017-12-22 20:13:01 +01:00
mmu.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
mmu_context.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
module.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
msi.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
page.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
param.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
parport.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
pci.h
PCI: remove PCI_DMA_BUS_IS_PHYS
2018-05-07 07:15:41 +02:00
pci_iomap.h
mn10300: Remove the architecture
2018-03-09 23:19:56 +01:00
percpu.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
pgalloc.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
pgtable-nop4d-hack.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
pgtable-nop4d.h
x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable
2018-02-14 13:11:14 +01:00
pgtable-nopmd.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
pgtable-nopud.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
pgtable.h
Merge branch 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2018-08-14 09:46:06 -07:00
preempt.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
ptrace.h
qrwlock.h
locking/qrwlock: Prevent slowpath writers getting held up by fastpath
2017-10-25 10:57:25 +02:00
qrwlock_types.h
locking/qrwlock: include asm/byteorder.h as needed
2018-02-06 10:28:58 +01:00
qspinlock.h
locking/spinlocks: Clean up comment and #ifndef for {,queued_}spin_is_locked()
2018-05-15 08:11:15 +02:00
qspinlock_types.h
locking/qspinlock: Fix build for anonymous union in older GCC compilers
2018-06-22 04:19:16 +02:00
resource.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
rwsem.h
Merge branch 'linus' into locking/core, to resolve conflicts
2017-11-07 10:32:44 +01:00
seccomp.h
seccomp: Get compat syscalls from asm-generic header
2016-05-13 14:02:00 +02:00
sections.h
sections: split dereference_function_descriptor()
2018-01-09 10:45:37 +01:00
segment.h
serial.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
set_memory.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
signal.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
simd.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
sizes.h
spinlock.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
statfs.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
string.h
switch_to.h
mn10300: Remove the architecture
2018-03-09 23:19:56 +01:00
syscall.h
syscalls.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
termios-base.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
termios.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
timex.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
tlb.h
x86/mm/tlb: Leave lazy TLB mode at page table free time
2018-07-17 09:35:31 +02:00
tlbflush.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
topology.h
include/asm-generic/topology.h: remove unused parent_node() macro
2017-11-17 16:10:05 -08:00
trace_clock.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
uaccess.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
unaligned.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
unistd.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
user.h
vga.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
vmlinux.lds.h
kbuild: Fix asm-generic/vmlinux.lds.h for LD_DEAD_CODE_DATA_ELIMINATION
2018-05-17 22:45:00 +09:00
vtime.h
word-at-a-time.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
xor.h