Pull x86 platform updates from Thomas Gleixner:
"Trivial cleanups and improvements"
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/platform/UV: Remove redundant check of p == q
x86/platform/olpc: Use PTR_ERR_OR_ZERO()
x86/platform/UV: Mark memblock related init code and data correctly
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
...
Pull x86 dump printing cleanup from Thomas Gleixner:
"Clean up the show_opcodes() printout so nested dumps can be properly
differentiated"
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Avoid pr_cont() in show_opcodes()
Pull x86 cpu updates from Thomas Gleixner:
"Two small updates for the CPU code:
- Improve NUMA emulation
- Add the EPT_AD CPU feature bit"
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpufeatures: Add EPT_AD feature bit
x86/numa_emulation: Introduce uniform split capability
x86/numa_emulation: Fix emulated-to-physical node mapping
Pull x86 cleanups from Thomas Gleixner:
"Trival cleanups"
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/iommu: Use NULL instead of 0
x86/platform/pcspeaker: Use PTR_ERR_OR_ZERO() to fix ptr_ret.cocci warning
Pull x86 asm updates from Thomas Gleixner:
"The lowlevel and ASM code updates for x86:
- Make stack trace unwinding more reliable
- ASM instruction updates for better code generation
- Various cleanups"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry/64: Add two more instruction suffixes
x86/asm/64: Use 32-bit XOR to zero registers
x86/build/vdso: Simplify 'cmd_vdso2c'
x86/build/vdso: Remove unused vdso-syms.lds
x86/stacktrace: Enable HAVE_RELIABLE_STACKTRACE for the ORC unwinder
x86/unwind/orc: Detect the end of the stack
x86/stacktrace: Do not fail for ORC with regs on stack
x86/stacktrace: Clarify the reliable success paths
x86/stacktrace: Remove STACKTRACE_DUMP_ONCE
x86/stacktrace: Do not unwind after user regs
x86/asm: Use CC_SET/CC_OUT in percpu_cmpxchg8b_double() to micro-optimize code generation
Pull x86 apic update from Thomas Gleixner:
"Trivial cleanups of the APIC related code"
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Trivial coding style fixes
x86/vector: Merge allocate_vector() into assign_vector_locked()
Pull perf update from Thomas Gleixner:
"The perf crowd presents:
Kernel updates:
- Removal of jprobes
- Cleanup and consolidatation the handling of kprobes
- Cleanup and consolidation of hardware breakpoints
- The usual pile of fixes and updates to PMUs and event descriptors
Tooling updates:
- Updates and improvements all over the place. Nothing outstanding,
just the (good) boring incremental grump work"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
perf trace: Do not require --no-syscalls to suppress strace like output
perf bpf: Include uapi/linux/bpf.h from the 'perf trace' script's bpf.h
perf tools: Allow overriding MAX_NR_CPUS at compile time
perf bpf: Show better message when failing to load an object
perf list: Unify metric group description format with PMU event description
perf vendor events arm64: Update ThunderX2 implementation defined pmu core events
perf cs-etm: Generate branch sample for CS_ETM_TRACE_ON packet
perf cs-etm: Generate branch sample when receiving a CS_ETM_TRACE_ON packet
perf cs-etm: Support dummy address value for CS_ETM_TRACE_ON packet
perf cs-etm: Fix start tracing packet handling
perf build: Fix installation directory for eBPF
perf c2c report: Fix crash for empty browser
perf tests: Fix indexing when invoking subtests
perf trace: Beautify the AF_INET & AF_INET6 'socket' syscall 'protocol' args
perf trace beauty: Add beautifiers for 'socket''s 'protocol' arg
perf trace beauty: Do not print NULL strarray entries
perf beauty: Add a generator for IPPROTO_ socket's protocol constants
tools include uapi: Grab a copy of linux/in.h
perf tests: Fix complex event name parsing
perf evlist: Fix error out while applying initial delay and LBR
...
Pull scheduler updates from Thomas Gleixner:
- Cleanup and improvement of NUMA balancing
- Refactoring and improvements to the PELT (Per Entity Load Tracking)
code
- Watchdog simplification and related cleanups
- The usual pile of small incremental fixes and improvements
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
watchdog: Reduce message verbosity
stop_machine: Reflow cpu_stop_queue_two_works()
sched/numa: Move task_numa_placement() closer to numa_migrate_preferred()
sched/numa: Use group_weights to identify if migration degrades locality
sched/numa: Update the scan period without holding the numa_group lock
sched/numa: Remove numa_has_capacity()
sched/numa: Modify migrate_swap() to accept additional parameters
sched/numa: Remove unused task_capacity from 'struct numa_stats'
sched/numa: Skip nodes that are at 'hoplimit'
sched/debug: Reverse the order of printing faults
sched/numa: Use task faults only if numa_group is not yet set up
sched/numa: Set preferred_node based on best_cpu
sched/numa: Simplify load_too_imbalanced()
sched/numa: Evaluate move once per node
sched/numa: Remove redundant field
sched/debug: Show the sum wait time of a task group
sched/fair: Remove #ifdefs from scale_rt_capacity()
sched/core: Remove get_cpu() from sched_fork()
sched/cpufreq: Clarify sugov_get_util()
sched/sysctl: Remove unused sched_time_avg_ms sysctl
...
Pull x86 RAS updates from Thomas Gleixner:
"A small set of changes to the RAS core:
- Rework of the MCE bank scanning code
- Y2038 converion"
* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Cleanup __mc_scan_banks()
x86/mce: Carve out bank scanning code
x86/mce: Remove !banks check
x86/mce: Carve out the crashing_cpu check
x86/mce: Always use 64-bit timestamps
The kernel unnecessarily prevents late microcode loading when SMT is
disabled. It should be safe to allow it if all the primary threads are
online.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Nadav reported that on guests we're failing to rewrite the indirect
calls to CALLEE_SAVE paravirt functions. In particular the
pv_queued_spin_unlock() call is left unpatched and that is all over the
place. This obviously wrecks Spectre-v2 mitigation (for paravirt
guests) which relies on not actually having indirect calls around.
The reason is an incorrect clobber test in paravirt_patch_call(); this
function rewrites an indirect call with a direct call to the _SAME_
function, there is no possible way the clobbers can be different
because of this.
Therefore remove this clobber check. Also put WARNs on the other patch
failure case (not enough room for the instruction) which I've not seen
trigger in my (limited) testing.
Three live kernel image disassemblies for lock_sock_nested (as a small
function that illustrates the problem nicely). PRE is the current
situation for guests, POST is with this patch applied and NATIVE is with
or without the patch for !guests.
PRE:
(gdb) disassemble lock_sock_nested
Dump of assembler code for function lock_sock_nested:
0xffffffff817be970 <+0>: push %rbp
0xffffffff817be971 <+1>: mov %rdi,%rbp
0xffffffff817be974 <+4>: push %rbx
0xffffffff817be975 <+5>: lea 0x88(%rbp),%rbx
0xffffffff817be97c <+12>: callq 0xffffffff819f7160 <_cond_resched>
0xffffffff817be981 <+17>: mov %rbx,%rdi
0xffffffff817be984 <+20>: callq 0xffffffff819fbb00 <_raw_spin_lock_bh>
0xffffffff817be989 <+25>: mov 0x8c(%rbp),%eax
0xffffffff817be98f <+31>: test %eax,%eax
0xffffffff817be991 <+33>: jne 0xffffffff817be9ba <lock_sock_nested+74>
0xffffffff817be993 <+35>: movl $0x1,0x8c(%rbp)
0xffffffff817be99d <+45>: mov %rbx,%rdi
0xffffffff817be9a0 <+48>: callq *0xffffffff822299e8
0xffffffff817be9a7 <+55>: pop %rbx
0xffffffff817be9a8 <+56>: pop %rbp
0xffffffff817be9a9 <+57>: mov $0x200,%esi
0xffffffff817be9ae <+62>: mov $0xffffffff817be993,%rdi
0xffffffff817be9b5 <+69>: jmpq 0xffffffff81063ae0 <__local_bh_enable_ip>
0xffffffff817be9ba <+74>: mov %rbp,%rdi
0xffffffff817be9bd <+77>: callq 0xffffffff817be8c0 <__lock_sock>
0xffffffff817be9c2 <+82>: jmp 0xffffffff817be993 <lock_sock_nested+35>
End of assembler dump.
POST:
(gdb) disassemble lock_sock_nested
Dump of assembler code for function lock_sock_nested:
0xffffffff817be970 <+0>: push %rbp
0xffffffff817be971 <+1>: mov %rdi,%rbp
0xffffffff817be974 <+4>: push %rbx
0xffffffff817be975 <+5>: lea 0x88(%rbp),%rbx
0xffffffff817be97c <+12>: callq 0xffffffff819f7160 <_cond_resched>
0xffffffff817be981 <+17>: mov %rbx,%rdi
0xffffffff817be984 <+20>: callq 0xffffffff819fbb00 <_raw_spin_lock_bh>
0xffffffff817be989 <+25>: mov 0x8c(%rbp),%eax
0xffffffff817be98f <+31>: test %eax,%eax
0xffffffff817be991 <+33>: jne 0xffffffff817be9ba <lock_sock_nested+74>
0xffffffff817be993 <+35>: movl $0x1,0x8c(%rbp)
0xffffffff817be99d <+45>: mov %rbx,%rdi
0xffffffff817be9a0 <+48>: callq 0xffffffff810a0c20 <__raw_callee_save___pv_queued_spin_unlock>
0xffffffff817be9a5 <+53>: xchg %ax,%ax
0xffffffff817be9a7 <+55>: pop %rbx
0xffffffff817be9a8 <+56>: pop %rbp
0xffffffff817be9a9 <+57>: mov $0x200,%esi
0xffffffff817be9ae <+62>: mov $0xffffffff817be993,%rdi
0xffffffff817be9b5 <+69>: jmpq 0xffffffff81063aa0 <__local_bh_enable_ip>
0xffffffff817be9ba <+74>: mov %rbp,%rdi
0xffffffff817be9bd <+77>: callq 0xffffffff817be8c0 <__lock_sock>
0xffffffff817be9c2 <+82>: jmp 0xffffffff817be993 <lock_sock_nested+35>
End of assembler dump.
NATIVE:
(gdb) disassemble lock_sock_nested
Dump of assembler code for function lock_sock_nested:
0xffffffff817be970 <+0>: push %rbp
0xffffffff817be971 <+1>: mov %rdi,%rbp
0xffffffff817be974 <+4>: push %rbx
0xffffffff817be975 <+5>: lea 0x88(%rbp),%rbx
0xffffffff817be97c <+12>: callq 0xffffffff819f7160 <_cond_resched>
0xffffffff817be981 <+17>: mov %rbx,%rdi
0xffffffff817be984 <+20>: callq 0xffffffff819fbb00 <_raw_spin_lock_bh>
0xffffffff817be989 <+25>: mov 0x8c(%rbp),%eax
0xffffffff817be98f <+31>: test %eax,%eax
0xffffffff817be991 <+33>: jne 0xffffffff817be9ba <lock_sock_nested+74>
0xffffffff817be993 <+35>: movl $0x1,0x8c(%rbp)
0xffffffff817be99d <+45>: mov %rbx,%rdi
0xffffffff817be9a0 <+48>: movb $0x0,(%rdi)
0xffffffff817be9a3 <+51>: nopl 0x0(%rax)
0xffffffff817be9a7 <+55>: pop %rbx
0xffffffff817be9a8 <+56>: pop %rbp
0xffffffff817be9a9 <+57>: mov $0x200,%esi
0xffffffff817be9ae <+62>: mov $0xffffffff817be993,%rdi
0xffffffff817be9b5 <+69>: jmpq 0xffffffff81063ae0 <__local_bh_enable_ip>
0xffffffff817be9ba <+74>: mov %rbp,%rdi
0xffffffff817be9bd <+77>: callq 0xffffffff817be8c0 <__lock_sock>
0xffffffff817be9c2 <+82>: jmp 0xffffffff817be993 <lock_sock_nested+35>
End of assembler dump.
Fixes: 63f70270cc ("[PATCH] i386: PARAVIRT: add common patching machinery")
Fixes: 3010a0663f ("x86/paravirt, objtool: Annotate indirect calls")
Reported-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: stable@vger.kernel.org
Josh reported that the late SMT evaluation in cpu_smt_state_init() sets
cpu_smt_control to CPU_SMT_NOT_SUPPORTED in case that 'nosmt' was supplied
on the kernel command line as it cannot differentiate between SMT disabled
by BIOS and SMT soft disable via 'nosmt'. That wreckages the state and
makes the sysfs interface unusable.
Rework this so that during bringup of the non boot CPUs the availability of
SMT is determined in cpu_smt_allowed(). If a newly booted CPU is not a
'primary' thread then set the local cpu_smt_available marker and evaluate
this explicitely right after the initial SMP bringup has finished.
SMT evaulation on x86 is a trainwreck as the firmware has all the
information _before_ booting the kernel, but there is no interface to query
it.
Fixes: 73d5e2b472 ("cpu/hotplug: detect SMT disabled by BIOS")
Reported-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Commit d94a155c59 ("x86/cpu: Prevent cpuinfo_x86::x86_phys_bits
adjustment corruption") has moved the query and calculation of the
x86_virt_bits and x86_phys_bits fields of the cpuinfo_x86 struct
from the get_cpu_cap function to a new function named
get_cpu_address_sizes.
One of the call sites related to Xen PV VMs was unfortunately missed
in the aforementioned commit. This prevents successful boot-up of
kernel versions 4.17 and up in Xen PV VMs if CONFIG_DEBUG_VIRTUAL
is enabled, due to the following code path:
enlighten_pv.c::xen_start_kernel
mmu_pv.c::xen_reserve_special_pages
page.h::__pa
physaddr.c::__phys_addr
physaddr.h::phys_addr_valid
phys_addr_valid uses boot_cpu_data.x86_phys_bits to validate physical
addresses. boot_cpu_data.x86_phys_bits is no longer populated before
the call to xen_reserve_special_pages due to the aforementioned commit
though, so the validation performed by phys_addr_valid fails, which
causes __phys_addr to trigger a BUG, preventing boot-up.
Signed-off-by: M. Vefa Bicakci <m.v.b@runbox.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: xen-devel@lists.xenproject.org
Cc: x86@kernel.org
Cc: stable@vger.kernel.org # for v4.17 and up
Fixes: d94a155c59 ("x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption")
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Implement paravirtual apic hooks to enable PV IPIs for KVM if the "send IPI"
hypercall is available. The hypercall lets a guest send IPIs, with
at most 128 destinations per hypercall in 64-bit mode and 64 vCPUs per
hypercall in 32-bit mode.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add kvm hypervisor init time platform setup callback which
will be used to replace native apic hooks by pararvirtual
hooks.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On a VM with only 1 vCPU, the locking fast path will always be
successful. In this case, there is no need to use the the PV qspinlock
code which has higher overhead on the unlock side than the native
qspinlock code.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Bit 3 of ARCH_CAPABILITIES tells a hypervisor that L1D flush on vmentry is
not needed. Add a new value to enum vmx_l1d_flush_state, which is used
either if there is no L1TF bug at all, or if bit 3 is set in ARCH_CAPABILITIES.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Three changes to the content of the sysfs file:
- If EPT is disabled, L1TF cannot be exploited even across threads on the
same core, and SMT is irrelevant.
- If mitigation is completely disabled, and SMT is enabled, print "vulnerable"
instead of "vulnerable, SMT vulnerable"
- Reorder the two parts so that the main vulnerability state comes first
and the detail on SMT is second.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The last missing piece to having vmx_l1d_flush() take interrupts after
VMEXIT into account is to set the kvm_cpu_l1tf_flush_l1d per-cpu flag on
irq entry.
Issue calls to kvm_set_cpu_l1tf_flush_l1d() from entering_irq(),
ipi_entering_ack_irq(), smp_reschedule_interrupt() and
uv_bau_message_interrupt().
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The next patch in this series will have to make the definition of
irq_cpustat_t available to entering_irq().
Inclusion of asm/hardirq.h into asm/apic.h would cause circular header
dependencies like
asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/topology.h
linux/smp.h
asm/smp.h
or
linux/gfp.h
linux/mmzone.h
asm/mmzone.h
asm/mmzone_64.h
asm/smp.h
asm/apic.h
asm/hardirq.h
linux/irq.h
linux/irqdesc.h
linux/kobject.h
linux/sysfs.h
linux/kernfs.h
linux/idr.h
linux/gfp.h
and others.
This causes compilation errors because of the header guards becoming
effective in the second inclusion: symbols/macros that had been defined
before wouldn't be available to intermediate headers in the #include chain
anymore.
A possible workaround would be to move the definition of irq_cpustat_t
into its own header and include that from both, asm/hardirq.h and
asm/apic.h.
However, this wouldn't solve the real problem, namely asm/harirq.h
unnecessarily pulling in all the linux/irq.h cruft: nothing in
asm/hardirq.h itself requires it. Also, note that there are some other
archs, like e.g. arm64, which don't have that #include in their
asm/hardirq.h.
Remove the linux/irq.h #include from x86' asm/hardirq.h.
Fix resulting compilation errors by adding appropriate #includes to *.c
files as needed.
Note that some of these *.c files could be cleaned up a bit wrt. to their
set of #includes, but that should better be done from separate patches, if
at all.
Signed-off-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Peter is objecting to the direct PMU access in RDT. Right now the PMU usage
is broken anyway as it is not coordinated with perf.
Until this discussion settled, disable the PMU mechanics by simply
rejecting the type '2' measurement in the resctrl file.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
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: hpa@zytor.com
Future Intel processors will support "Enhanced IBRS" which is an "always
on" mode i.e. IBRS bit in SPEC_CTRL MSR is enabled once and never
disabled.
From the specification [1]:
"With enhanced IBRS, the predicted targets of indirect branches
executed cannot be controlled by software that was executed in a less
privileged predictor mode or on another logical processor. As a
result, software operating on a processor with enhanced IBRS need not
use WRMSR to set IA32_SPEC_CTRL.IBRS after every transition to a more
privileged predictor mode. Software can isolate predictor modes
effectively simply by setting the bit once. Software need not disable
enhanced IBRS prior to entering a sleep state such as MWAIT or HLT."
If Enhanced IBRS is supported by the processor then use it as the
preferred spectre v2 mitigation mechanism instead of Retpoline. Intel's
Retpoline white paper [2] states:
"Retpoline is known to be an effective branch target injection (Spectre
variant 2) mitigation on Intel processors belonging to family 6
(enumerated by the CPUID instruction) that do not have support for
enhanced IBRS. On processors that support enhanced IBRS, it should be
used for mitigation instead of retpoline."
The reason why Enhanced IBRS is the recommended mitigation on processors
which support it is that these processors also support CET which
provides a defense against ROP attacks. Retpoline is very similar to ROP
techniques and might trigger false positives in the CET defense.
If Enhanced IBRS is selected as the mitigation technique for spectre v2,
the IBRS bit in SPEC_CTRL MSR is set once at boot time and never
cleared. Kernel also has to make sure that IBRS bit remains set after
VMEXIT because the guest might have cleared the bit. This is already
covered by the existing x86_spec_ctrl_set_guest() and
x86_spec_ctrl_restore_host() speculation control functions.
Enhanced IBRS still requires IBPB for full mitigation.
[1] Speculative-Execution-Side-Channel-Mitigations.pdf
[2] Retpoline-A-Branch-Target-Injection-Mitigation.pdf
Both documents are available at:
https://bugzilla.kernel.org/show_bug.cgi?id=199511
Originally-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim C Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Link: https://lkml.kernel.org/r/1533148945-24095-1-git-send-email-sai.praneeth.prakhya@intel.com
Some Intel processors have an EPT feature whereby the accessed & dirty bits
in EPT entries can be updated by HW. MSR IA32_VMX_EPT_VPID_CAP exposes the
presence of this capability.
There is no point in trying to use that new feature bit in the VMX code as
VMX needs to read the MSR anyway to access other bits, but having the
feature bit for EPT_AD in place helps virtualization management as it
exposes "ept_ad" in /proc/cpuinfo/$proc/flags if the feature is present.
[ tglx: Amended changelog ]
Signed-off-by: Peter Feiner <pfeiner@google.com>
Signed-off-by: Peter Shier <pshier@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jim Mattson <jmattson@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lkml.kernel.org/r/20180801180657.138051-1-pshier@google.com
The BTF conflicts were simple overlapping changes.
The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.
Signed-off-by: David S. Miller <davem@davemloft.net>
The article "Spectre Returns! Speculation Attacks using the Return Stack
Buffer" [1] describes two new (sub-)variants of spectrev2-like attacks,
making use solely of the RSB contents even on CPUs that don't fallback to
BTB on RSB underflow (Skylake+).
Mitigate userspace-userspace attacks by always unconditionally filling RSB on
context switch when the generic spectrev2 mitigation has been enabled.
[1] https://arxiv.org/pdf/1807.07940.pdf
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/nycvar.YFH.7.76.1807261308190.997@cbobk.fhfr.pm
There is nothing arch-specific about PCI or dma-debug, so call
dma_debug_add_bus() from the PCI core just after registering the bus type.
Most of dma-debug is already generic; this just adds reporting of pending
dma-allocations on driver unload for arches other than powerpc, sh, and
x86.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
parse_mem_block_size() and mem_block_size are only used during init. Mark
them accordingly.
Fixes: d7609f4210 ("x86/platform/UV: Add kernel parameter to set memory block size")
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: hpa@zytor.com
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Andrew Banman <andrew.banman@hpe.com>
Link: https://lkml.kernel.org/r/20180730075947.23023-1-douly.fnst@cn.fujitsu.com
kvm_get_preset_lpj() is only called from kvmclock_init(), so mark it __init
as well.
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář<rkrcmar@redhat.com>
Cc: <kvm@vger.kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Link: https://lkml.kernel.org/r/20180730075421.22830-3-douly.fnst@cn.fujitsu.com
Split out suplicated code from tsc_early_init() and tsc_init() into a
common helper and fixup some comment typos.
[ tglx: Massaged changelog and renamed function ]
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180730075421.22830-2-douly.fnst@cn.fujitsu.com
Fuzzing the PTI-x86-32 code with trinity showed unhandled
kernel paging request oops-messages that looked a lot like
silent data corruption.
Lot's of debugging and testing lead to the kexec-32bit code,
which is still allocating 4k PGDs when PTI is enabled. But
since it uses native_set_pud() to build the page-table, it
will unevitably call into __pti_set_user_pgtbl(), which
writes beyond the allocated 4k page.
Use PGD_ALLOCATION_ORDER to allocate PGDs in the kexec code
to fix the issue.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: David H. Gutteridge <dhgutteridge@sympatico.ca>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1532533683-5988-4-git-send-email-joro@8bytes.org
Whilst the notion of an upstream DMA restriction is most commonly seen
in PCI host bridges saddled with a 32-bit native interface, a more
general version of the same issue can exist on complex SoCs where a bus
or point-to-point interconnect link from a device's DMA master interface
to another component along the path to memory (often an IOMMU) may carry
fewer address bits than the interfaces at both ends nominally support.
In order to properly deal with this, the first step is to expand the
dma_32bit_limit flag into an arbitrary mask.
To minimise the impact on existing code, we'll make sure to only
consider this new mask valid if set. That makes sense anyway, since a
mask of zero would represent DMA not being wired up at all, and that
would be better handled by not providing valid ops in the first place.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This allows the default behavior to be controlled by a kernel config
option instead of changing the commandline for the kernel to include
"iommu.passthrough=on" or "iommu=pt" on machines where this is desired.
Likewise, for machines where this config option is enabled, it can be
disabled at boot time with "iommu.passthrough=off" or "iommu=nopt".
Also corrected iommu=pt documentation for IA-64, since it has no code that
parses iommu= at all.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
All SKX with stepping higher than 4 support the TSC_DEADLINE,
no matter the microcode version.
Without this patch, upcoming SKX steppings will not be able to use
their TSC_DEADLINE timer.
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: <stable@kernel.org> # v4.14+
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 616dd5872e ("x86/apic: Update TSC_DEADLINE quirk with additional SKX stepping")
Link: http://lkml.kernel.org/r/d0c7129e509660be9ec6b233284b8d42d90659e8.1532207856.git.len.brown@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The ptr_ret.cocci script generates the following warning:
arch/x86/kernel/pcspeaker.c:12:8-14: WARNING: PTR_ERR_OR_ZERO can be used
Use PTR_ERR_OR_ZERO() rather than an open-coded version to fix this.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: gregkh@linuxfoundation.org
Cc: kstewart@linuxfoundation.org
Cc: pombredanne@nexb.com
Link: http://lkml.kernel.org/r/20180720073213.14996-1-yuehaibing@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fix from Ingo Molnar:
"A single fix for a MCE-polling regression, which prevented the
disabling of polling"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/MCE: Remove min interval polling limitation
Pull x86 pti fixes from Ingo Molnar:
"An APM fix, and a BTS hardware-tracing fix related to PTI changes"
* 'x86-pti-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apm: Don't access __preempt_count with zeroed fs
x86/events/intel/ds: Fix bts_interrupt_threshold alignment
This change allows creating kernfs files and directories with arbitrary
uid/gid instead of always using GLOBAL_ROOT_UID/GID by extending
kernfs_create_dir_ns() and kernfs_create_file_ns() with uid/gid arguments.
The "simple" kernfs_create_file() and kernfs_create_dir() are left alone
and always create objects belonging to the global root.
When creating symlinks ownership (uid/gid) is taken from the target kernfs
object.
Co-Developed-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds the needed special case for PAE to get the LDT mapped into the
user page-table when PTI is enabled. The big difference to the other paging
modes is that on PAE there is no full top-level PGD entry available for the
LDT, but only a PMD entry.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-37-git-send-email-joro@8bytes.org
This splits out the mapping sanity check and the actual mapping of the LDT
to user-space from the map_ldt_struct() function in a way so that it is
re-usable for PAE paging.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-36-git-send-email-joro@8bytes.org
It marks the end of the address-space range reserved for the LDT. The
LDT-code will use it when unmapping the LDT for user-space.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-35-git-send-email-joro@8bytes.org
The pti_clone_kernel_text() function references __end_rodata_hpage_align,
which is only present on x86-64. This makes sense as the end of the rodata
section is not huge-page aligned on 32 bit.
Nevertheless a symbol is required for the function that points at the right
address for both 32 and 64 bit. Introduce __end_rodata_aligned for that
purpose and use it in pti_clone_kernel_text().
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-28-git-send-email-joro@8bytes.org
Allocate a kernel and a user page-table root when PTI is enabled. Also
allocate a full page per root for PAE because otherwise the bit to flip in
CR3 to switch between them would be non-constant, which creates a lot of
hassle. Keep that for a later optimization.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-18-git-send-email-joro@8bytes.org
The function does not update sp0 anymore but updates makes the task-stack
visible for entry code. This is by either writing it to sp1 or by doing a
hypercall. Rename the function to get rid of the misleading name.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-15-git-send-email-joro@8bytes.org
Use the entry-stack as a trampoline to enter the kernel. The entry-stack is
already in the cpu_entry_area and will be mapped to userspace when PTI is
enabled.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-8-git-send-email-joro@8bytes.org
x86_tss.sp0 will be used to point to the entry stack later to use it as a
trampoline stack for other kernel entry points besides SYSENTER.
So store the real task stack pointer in x86_tss.sp1, which is otherwise
unused by the hardware, as Linux doesn't make use of Ring 1.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-4-git-send-email-joro@8bytes.org
The stack address doesn't need to be stored in tss.sp0 if the stack is
switched manually like on sysenter. Rename the offset so that it still
makes sense when its location is changed in later patches.
This stackk will also be used for all kernel-entry points, not just
sysenter. Reflect that and the fact that it is the offset to the task-stack
location in the name as well.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-3-git-send-email-joro@8bytes.org
These offsets will be used in 32 bit assembly code as well, so make them
available for all of x86 code.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.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: 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: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-2-git-send-email-joro@8bytes.org
It supposed to be safe to modify static branches after jump_label_init().
But, because static key modifying code eventually calls text_poke() it can
end up accessing a struct page which has not been initialized yet.
Here is how to quickly reproduce the problem. Insert code like this
into init/main.c:
| +static DEFINE_STATIC_KEY_FALSE(__test);
| asmlinkage __visible void __init start_kernel(void)
| {
| char *command_line;
|@@ -587,6 +609,10 @@ asmlinkage __visible void __init start_kernel(void)
| vfs_caches_init_early();
| sort_main_extable();
| trap_init();
|+ {
|+ static_branch_enable(&__test);
|+ WARN_ON(!static_branch_likely(&__test));
|+ }
| mm_init();
The following warnings show-up:
WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:701 text_poke+0x20d/0x230
RIP: 0010:text_poke+0x20d/0x230
Call Trace:
? text_poke_bp+0x50/0xda
? arch_jump_label_transform+0x89/0xe0
? __jump_label_update+0x78/0xb0
? static_key_enable_cpuslocked+0x4d/0x80
? static_key_enable+0x11/0x20
? start_kernel+0x23e/0x4c8
? secondary_startup_64+0xa5/0xb0
---[ end trace abdc99c031b8a90a ]---
If the code above is moved after mm_init(), no warning is shown, as struct
pages are initialized during handover from memblock.
Use text_poke_early() in static branching until early boot IRQs are enabled
and from there switch to text_poke. Also, ensure text_poke() is never
invoked when unitialized memory access may happen by using adding a
!after_bootmem assertion.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
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: douly.fnst@cn.fujitsu.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/20180719205545.16512-9-pasha.tatashin@oracle.com
If concurrent printk() messages are emitted, then pr_cont() is making it
extremly hard to decode which part of the output belongs to what. See the
convoluted example at:
https://syzkaller.appspot.com/text?tag=CrashReport&x=139d342c400000
Avoid this by using a proper prefix for each line and by using %ph format
in show_opcodes() which emits the 'Code:' line in one go.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: joe@perches.com
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/1532009278-5953-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"Miscellaneous bugfixes, plus a small patchlet related to Spectre v2"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvmclock: fix TSC calibration for nested guests
KVM: VMX: Mark VMXArea with revision_id of physical CPU even when eVMCS enabled
KVM: irqfd: fix race between EPOLLHUP and irq_bypass_register_consumer
KVM/Eventfd: Avoid crash when assign and deassign specific eventfd in parallel.
x86/kvmclock: set pvti_cpu0_va after enabling kvmclock
x86/kvm/Kconfig: Ensure CRYPTO_DEV_CCP_DD state at minimum matches KVM_AMD
kvm: nVMX: Restore exit qual for VM-entry failure due to MSR loading
x86/kvm/vmx: don't read current->thread.{fs,gs}base of legacy tasks
KVM: VMX: support MSR_IA32_ARCH_CAPABILITIES as a feature MSR
Inside a nested guest, access to hardware can be slow enough that
tsc_read_refs always return ULLONG_MAX, causing tsc_refine_calibration_work
to be called periodically and the nested guest to spend a lot of time
reading the ACPI timer.
However, if the TSC frequency is available from the pvclock page,
we can just set X86_FEATURE_TSC_KNOWN_FREQ and avoid the recalibration.
'refine' operation.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
[Commit message rewritten. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
commit b3b7c4795c ("x86/MCE: Serialize sysfs changes") introduced a min
interval limitation when setting the check interval for polled MCEs.
However, the logic is that 0 disables polling for corrected MCEs, see
Documentation/x86/x86_64/machinecheck. The limitation prevents disabling.
Remove this limitation and allow the value 0 to disable polling again.
Fixes: b3b7c4795c ("x86/MCE: Serialize sysfs changes")
Signed-off-by: Dewet Thibaut <thibaut.dewet@nokia.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
[ Massage commit message. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180716084927.24869-1-alexander.sverdlin@nokia.com
pvti_cpu0_va is the address of shared kvmclock data structure.
pvti_cpu0_va is currently kept unset (1) on 32 bit systems, (2) when
kvmclock vsyscall is disabled, and (3) if kvmclock is not stable.
This poses a problem, because kvm_ptp needs pvti_cpu0_va, but (1) can
work on 32 bit, (2) has little relation to the vsyscall, and (3) does
not need stable kvmclock (although kvmclock won't be used for system
clock if it's not stable, so kvm_ptp is pointless in that case).
Expose pvti_cpu0_va whenever kvmclock is enabled to allow all users to
work with it.
This fixes a regression found on Gentoo: https://bugs.gentoo.org/658544.
Fixes: 9f08890ab9 ("x86/pvclock: add setter for pvclock_pvti_cpu0_va")
Cc: stable@vger.kernel.org
Reported-by: Andreas Steinmetz <ast@domdv.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce the 'l1tf=' kernel command line option to allow for boot-time
switching of mitigation that is used on processors affected by L1TF.
The possible values are:
full
Provides all available mitigations for the L1TF vulnerability. Disables
SMT and enables all mitigations in the hypervisors. SMT control via
/sys/devices/system/cpu/smt/control is still possible after boot.
Hypervisors will issue a warning when the first VM is started in
a potentially insecure configuration, i.e. SMT enabled or L1D flush
disabled.
full,force
Same as 'full', but disables SMT control. Implies the 'nosmt=force'
command line option. sysfs control of SMT and the hypervisor flush
control is disabled.
flush
Leaves SMT enabled and enables the conditional hypervisor mitigation.
Hypervisors will issue a warning when the first VM is started in a
potentially insecure configuration, i.e. SMT enabled or L1D flush
disabled.
flush,nosmt
Disables SMT and enables the conditional hypervisor mitigation. SMT
control via /sys/devices/system/cpu/smt/control is still possible
after boot. If SMT is reenabled or flushing disabled at runtime
hypervisors will issue a warning.
flush,nowarn
Same as 'flush', but hypervisors will not warn when
a VM is started in a potentially insecure configuration.
off
Disables hypervisor mitigations and doesn't emit any warnings.
Default is 'flush'.
Let KVM adhere to these semantics, which means:
- 'lt1f=full,force' : Performe L1D flushes. No runtime control
possible.
- 'l1tf=full'
- 'l1tf-flush'
- 'l1tf=flush,nosmt' : Perform L1D flushes and warn on VM start if
SMT has been runtime enabled or L1D flushing
has been run-time enabled
- 'l1tf=flush,nowarn' : Perform L1D flushes and no warnings are emitted.
- 'l1tf=off' : L1D flushes are not performed and no warnings
are emitted.
KVM can always override the L1D flushing behavior using its 'vmentry_l1d_flush'
module parameter except when lt1f=full,force is set.
This makes KVM's private 'nosmt' option redundant, and as it is a bit
non-systematic anyway (this is something to control globally, not on
hypervisor level), remove that option.
Add the missing Documentation entry for the l1tf vulnerability sysfs file
while at it.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20180713142323.202758176@linutronix.de
The CPU_SMT_NOT_SUPPORTED state is set (if the processor does not support
SMT) when the sysfs SMT control file is initialized.
That was fine so far as this was only required to make the output of the
control file correct and to prevent writes in that case.
With the upcoming l1tf command line parameter, this needs to be set up
before the L1TF mitigation selection and command line parsing happens.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20180713142323.121795971@linutronix.de
All mitigation modes can be switched at run time with a static key now:
- Use sysfs_streq() instead of strcmp() to handle the trailing new line
from sysfs writes correctly.
- Make the static key management handle multiple invocations properly.
- Set the module parameter file to RW
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20180713142322.954525119@linutronix.de
If Extended Page Tables (EPT) are disabled or not supported, no L1D
flushing is required. The setup function can just avoid setting up the L1D
flush for the EPT=n case.
Invoke it after the hardware setup has be done and enable_ept has the
correct state and expose the EPT disabled state in the mitigation status as
well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20180713142322.612160168@linutronix.de
Store the effective mitigation of VMX in a status variable and use it to
report the VMX state in the l1tf sysfs file.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20180713142322.433098358@linutronix.de
Lockdep is reporting a possible circular locking dependency:
======================================================
WARNING: possible circular locking dependency detected
4.18.0-rc1-test-test+ #4 Not tainted
------------------------------------------------------
user_example/766 is trying to acquire lock:
0000000073479a0f (rdtgroup_mutex){+.+.}, at: pseudo_lock_dev_mmap
but task is already holding lock:
000000001ef7a35b (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x9f/0x
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&mm->mmap_sem){++++}:
_copy_to_user+0x1e/0x70
filldir+0x91/0x100
dcache_readdir+0x54/0x160
iterate_dir+0x142/0x190
__x64_sys_getdents+0xb9/0x170
do_syscall_64+0x86/0x200
entry_SYSCALL_64_after_hwframe+0x49/0xbe
-> #1 (&sb->s_type->i_mutex_key#3){++++}:
start_creating+0x60/0x100
debugfs_create_dir+0xc/0xc0
rdtgroup_pseudo_lock_create+0x217/0x4d0
rdtgroup_schemata_write+0x313/0x3d0
kernfs_fop_write+0xf0/0x1a0
__vfs_write+0x36/0x190
vfs_write+0xb7/0x190
ksys_write+0x52/0xc0
do_syscall_64+0x86/0x200
entry_SYSCALL_64_after_hwframe+0x49/0xbe
-> #0 (rdtgroup_mutex){+.+.}:
__mutex_lock+0x80/0x9b0
pseudo_lock_dev_mmap+0x2f/0x170
mmap_region+0x3d6/0x610
do_mmap+0x387/0x580
vm_mmap_pgoff+0xcf/0x110
ksys_mmap_pgoff+0x170/0x1f0
do_syscall_64+0x86/0x200
entry_SYSCALL_64_after_hwframe+0x49/0xbe
other info that might help us debug this:
Chain exists of:
rdtgroup_mutex --> &sb->s_type->i_mutex_key#3 --> &mm->mmap_sem
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&mm->mmap_sem);
lock(&sb->s_type->i_mutex_key#3);
lock(&mm->mmap_sem);
lock(rdtgroup_mutex);
*** DEADLOCK ***
1 lock held by user_example/766:
#0: 000000001ef7a35b (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x9f/0x110
rdtgroup_mutex is already being released temporarily during pseudo-lock
region creation to prevent the potential deadlock between rdtgroup_mutex
and mm->mmap_sem that is obtained during device_create(). Move the
debugfs creation into this area to avoid the same circular dependency.
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: hpa@zytor.com
Link: https://lkml.kernel.org/r/fffb57f9c6b8285904c9a60cc91ce21591af17fe.1531332480.git.reinette.chatre@intel.com
ICL changes the registers and addresses to 64 bits.
I also briefly looked at implementing an u64 version of the PCI config
read functions, but I concluded this wouldn't be trivial, so it's not
worth doing it for a single user that can't have any racing problems
while reading the register in two separate operations.
v2:
- Scrub the development (non-public) changelog (Joonas).
- Remove the i915.ko bits so this can be easily backported in order
to properly avoid stolen memory even on machines without i915.ko
(Joonas).
- CC stable for the reasons above.
Issue: VIZ-9250
CC: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Fixes: 412310019a ("drm/i915/icl: Add initial Icelake definitions.")
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180504203252.28048-1-paulo.r.zanoni@intel.com
Pull x86/pti updates from Thomas Gleixner:
"Two small fixes correcting the handling of SSB mitigations on AMD
processors"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/bugs: Fix the AMD SSBD usage of the SPEC_CTRL MSR
x86/bugs: Update when to check for the LS_CFG SSBD mitigation
Don't access the provided buffer out of bounds - this can cause a kernel
out-of-bounds read when invoked through sys_splice() or other things that
use kernel_write()/__kernel_write().
Fixes: 7f8ec5a4f0 ("x86/mtrr: Convert to use strncpy_from_user() helper")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180706215003.156702-1-jannh@google.com
The Hyper-V feature and hint flags in hyperv-tlfs.h are all defined
with the string "X64" in the name. Some of these flags are indeed
x86/x64 specific, but others are not. For the ones that are used
in architecture independent Hyper-V driver code, or will be used in
the upcoming support for Hyper-V for ARM64, this patch removes the
"X64" from the name.
This patch changes the flags that are currently known to be
used on multiple architectures. Hyper-V for ARM64 is still a
work-in-progress and the Top Level Functional Spec (TLFS) has not
been separated into x86/x64 and ARM64 areas. So additional flags
may need to be updated later.
This patch only changes symbol names. There are no functional
changes.
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the commit
7da7c15613 ("x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs")
introduced a common way for all Intel MID chips to get their TSC frequency
via MSRs, there is no need to keep a duplication in each of Intel MID
platform code.
Thus, remove the custom calibration code for good.
Note, there is slight difference in how to get frequency for (reserved?)
values in MSRs, i.e. legacy code enforces some defaults while new code just
uses 0 in that cases.
Suggested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Bin Gao <bin.gao@intel.com>
Link: https://lkml.kernel.org/r/20180629193113.84425-6-andriy.shevchenko@linux.intel.com
Use SPDX identifier and update year in Intel copyright line.
While here, remove file name from the file itself.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Link: https://lkml.kernel.org/r/20180629193113.84425-5-andriy.shevchenko@linux.intel.com
Move the code to use recently introduced INTEL_CPU_FAM6() macro and
drop custom version of x86_match_cpu() function.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Link: https://lkml.kernel.org/r/20180629193113.84425-3-andriy.shevchenko@linux.intel.com
Add a missing header otherwise compiler warns about missed prototype:
CC arch/x86/kernel/tsc_msr.o
arch/x86/kernel/tsc_msr.c:73:15: warning: no previous prototype for ‘cpu_khz_from_msr’ [-Wmissing-prototypes]
unsigned long cpu_khz_from_msr(void)
^~~~~~~~~~~~~~~~
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Link: https://lkml.kernel.org/r/20180629193113.84425-4-andriy.shevchenko@linux.intel.com
Add standard interrupt handler annotations to
hyperv_vector_handler(). This does not fix any observed
bug, but avoids potential removal of the code by link
time optimization and makes it consistent with
hv_stimer0_vector_handler in the same source file.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On AMD, the presence of the MSR_SPEC_CTRL feature does not imply that the
SSBD mitigation support should use the SPEC_CTRL MSR. Other features could
have caused the MSR_SPEC_CTRL feature to be set, while a different SSBD
mitigation option is in place.
Update the SSBD support to check for the actual SSBD features that will
use the SPEC_CTRL MSR.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 6ac2f49edb ("x86/bugs: Add AMD's SPEC_CTRL MSR usage")
Link: http://lkml.kernel.org/r/20180702213602.29202.33151.stgit@tlendack-t1.amdoffice.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If either the X86_FEATURE_AMD_SSBD or X86_FEATURE_VIRT_SSBD features are
present, then there is no need to perform the check for the LS_CFG SSBD
mitigation support.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.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/20180702213553.29202.21089.stgit@tlendack-t1.amdoffice.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On 32-bit kernels, __flush_tlb_all() may have read the CR4 shadow before the
initialization of CR4 shadow in cpu_init().
Fix it by adding an explicit cr4_init_shadow() call into start_secondary()
which is the first function called on non-boot SMP CPUs - ahead of the
__flush_tlb_all() call.
( This is somewhat of a layering violation, but start_secondary() does
CR4 bootstrap in the PCID case anyway. )
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: http://lkml.kernel.org/r/b07b6ae9-4b57-4b40-b9bc-50c2c67f1d91@default
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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
As the mode of a resource group changes, the operations it can support may
also change. One way in which the supported operations are managed is to
modify the permissions of the files within the resource group's resctrl
directory.
At the moment only two possible permissions are supported: the default
permissions or no permissions in support for when the operation is "locked
down". It is possible where an operation on a resource group may have more
possibilities. For example, if by default changes can be made to the
resource group by writing to a resctrl file while the current settings can
be obtained by reading from the file, then it may be possible that in
another mode it is only possible to read the current settings, and not
change them.
Make it possible to modify some of the permissions of a resctrl file in
support of a more flexible way to manage the operations on a resource
group. In this preparation work the original behavior is maintained where
all permissions are restored.
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/8773aadfade7bcb2c48a45fa294a04d2c03bb0a1.1530421961.git.reinette.chatre@intel.com
When a resource group enters pseudo-locksetup mode a pseudo_lock_region is
associated with it. When the user writes to the resource group's schemata
file the CBM of the requested pseudo-locked region is entered into the
pseudo_lock_region struct. If any part of pseudo-lock region creation fails
the resource group will remain in pseudo-locksetup mode with the
pseudo_lock_region associated with it.
In case of failure during pseudo-lock region creation care needs to be
taken to ensure that the pseudo_lock_region struct associated with the
resource group is cleared from any pseudo-locking data - especially the
CBM. This is because the existence of a pseudo_lock_region struct with a
CBM is significant in other areas of the code, for example, the display of
bit_usage and initialization of a new resource group.
Fix the error path of pseudo-lock region creation to ensure that the
pseudo_lock_region struct is cleared at each error exit.
Fixes: 018961ae55 ("x86/intel_rdt: Pseudo-lock region creation/removal core")
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/49b4782f6d204d122cee3499e642b2772a98d2b4.1530421026.git.reinette.chatre@intel.com
Dave Hansen reported, that it's outright dangerous to keep SMT siblings
disabled completely so they are stuck in the BIOS and wait for SIPI.
The reason is that Machine Check Exceptions are broadcasted to siblings and
the soft disabled sibling has CR4.MCE = 0. If a MCE is delivered to a
logical core with CR4.MCE = 0, it asserts IERR#, which shuts down or
reboots the machine. The MCE chapter in the SDM contains the following
blurb:
Because the logical processors within a physical package are tightly
coupled with respect to shared hardware resources, both logical
processors are notified of machine check errors that occur within a
given physical processor. If machine-check exceptions are enabled when
a fatal error is reported, all the logical processors within a physical
package are dispatched to the machine-check exception handler. If
machine-check exceptions are disabled, the logical processors enter the
shutdown state and assert the IERR# signal. When enabling machine-check
exceptions, the MCE flag in control register CR4 should be set for each
logical processor.
Reverting the commit which ignores siblings at enumeration time solves only
half of the problem. The core cpuhotplug logic needs to be adjusted as
well.
This thoughtful engineered mechanism also turns the boot process on all
Intel HT enabled systems into a MCE lottery. MCE is enabled on the boot CPU
before the secondary CPUs are brought up. Depending on the number of
physical cores the window in which this situation can happen is smaller or
larger. On a HSW-EX it's about 750ms:
MCE is enabled on the boot CPU:
[ 0.244017] mce: CPU supports 22 MCE banks
The corresponding sibling #72 boots:
[ 1.008005] .... node #0, CPUs: #72
That means if an MCE hits on physical core 0 (logical CPUs 0 and 72)
between these two points the machine is going to shutdown. At least it's a
known safe state.
It's obvious that the early boot can be hit by an MCE as well and then runs
into the same situation because MCEs are not yet enabled on the boot CPU.
But after enabling them on the boot CPU, it does not make any sense to
prevent the kernel from recovering.
Adjust the nosmt kernel parameter documentation as well.
Reverts: 2207def700 ("x86/apic: Ignore secondary threads if nosmt=force")
Reported-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Tony Luck <tony.luck@intel.com>
Move early dump functionality into common code so that it is available for
all architectures. No need to carry arch-specific reads around as the read
hooks are already initialized by the time pci_setup_device() is getting
called during scan.
Tested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
There is a kernel panic that is triggered when reading /proc/kpageflags
on the kernel booted with kernel parameter 'memmap=nn[KMG]!ss[KMG]':
BUG: unable to handle kernel paging request at fffffffffffffffe
PGD 9b20e067 P4D 9b20e067 PUD 9b210067 PMD 0
Oops: 0000 [#1] SMP PTI
CPU: 2 PID: 1728 Comm: page-types Not tainted 4.17.0-rc6-mm1-v4.17-rc6-180605-0816-00236-g2dfb086ef02c+ #160
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.fc28 04/01/2014
RIP: 0010:stable_page_flags+0x27/0x3c0
Code: 00 00 00 0f 1f 44 00 00 48 85 ff 0f 84 a0 03 00 00 41 54 55 49 89 fc 53 48 8b 57 08 48 8b 2f 48 8d 42 ff 83 e2 01 48 0f 44 c7 <48> 8b 00 f6 c4 01 0f 84 10 03 00 00 31 db 49 8b 54 24 08 4c 89 e7
RSP: 0018:ffffbbd44111fde0 EFLAGS: 00010202
RAX: fffffffffffffffe RBX: 00007fffffffeff9 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000202 RDI: ffffed1182fff5c0
RBP: ffffffffffffffff R08: 0000000000000001 R09: 0000000000000001
R10: ffffbbd44111fed8 R11: 0000000000000000 R12: ffffed1182fff5c0
R13: 00000000000bffd7 R14: 0000000002fff5c0 R15: ffffbbd44111ff10
FS: 00007efc4335a500(0000) GS:ffff93a5bfc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffffe CR3: 00000000b2a58000 CR4: 00000000001406e0
Call Trace:
kpageflags_read+0xc7/0x120
proc_reg_read+0x3c/0x60
__vfs_read+0x36/0x170
vfs_read+0x89/0x130
ksys_pread64+0x71/0x90
do_syscall_64+0x5b/0x160
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7efc42e75e23
Code: 09 00 ba 9f 01 00 00 e8 ab 81 f4 ff 66 2e 0f 1f 84 00 00 00 00 00 90 83 3d 29 0a 2d 00 00 75 13 49 89 ca b8 11 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 db d3 01 00 48 89 04 24
According to kernel bisection, this problem became visible due to commit
f7f99100d8 ("mm: stop zeroing memory during allocation in vmemmap")
which changes how struct pages are initialized.
Memblock layout affects the pfn ranges covered by node/zone. Consider
that we have a VM with 2 NUMA nodes and each node has 4GB memory, and
the default (no memmap= given) memblock layout is like below:
MEMBLOCK configuration:
memory size = 0x00000001fff75c00 reserved size = 0x000000000300c000
memory.cnt = 0x4
memory[0x0] [0x0000000000001000-0x000000000009efff], 0x000000000009e000 bytes on node 0 flags: 0x0
memory[0x1] [0x0000000000100000-0x00000000bffd6fff], 0x00000000bfed7000 bytes on node 0 flags: 0x0
memory[0x2] [0x0000000100000000-0x000000013fffffff], 0x0000000040000000 bytes on node 0 flags: 0x0
memory[0x3] [0x0000000140000000-0x000000023fffffff], 0x0000000100000000 bytes on node 1 flags: 0x0
...
If you give memmap=1G!4G (so it just covers memory[0x2]),
the range [0x100000000-0x13fffffff] is gone:
MEMBLOCK configuration:
memory size = 0x00000001bff75c00 reserved size = 0x000000000300c000
memory.cnt = 0x3
memory[0x0] [0x0000000000001000-0x000000000009efff], 0x000000000009e000 bytes on node 0 flags: 0x0
memory[0x1] [0x0000000000100000-0x00000000bffd6fff], 0x00000000bfed7000 bytes on node 0 flags: 0x0
memory[0x2] [0x0000000140000000-0x000000023fffffff], 0x0000000100000000 bytes on node 1 flags: 0x0
...
This causes shrinking node 0's pfn range because it is calculated by the
address range of memblock.memory. So some of struct pages in the gap
range are left uninitialized.
We have a function zero_resv_unavail() which does zeroing the struct pages
within the reserved unavailable range (i.e. memblock.memory &&
!memblock.reserved). This patch utilizes it to cover all unavailable
ranges by putting them into memblock.reserved.
Link: http://lkml.kernel.org/r/20180615072947.GB23273@hori1.linux.bs1.fc.nec.co.jp
Fixes: f7f99100d8 ("mm: stop zeroing memory during allocation in vmemmap")
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Tested-by: Oscar Salvador <osalvador@suse.de>
Tested-by: "Herton R. Krzesinski" <herton@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Migrate to the new API in order to remove arch_validate_hwbkpt_settings()
that clumsily mixes up architecture validation and commit.
Original-patch-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joel Fernandes <joel.opensrc@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/1529981939-8231-4-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We can't pass the breakpoint directly on arch_check_bp_in_kernelspace()
anymore because its architecture internal datas (struct arch_hw_breakpoint)
are not yet filled by the time we call the function, and most
implementation need this backend to be up to date. So arrange the
function to take the probing struct instead.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joel Fernandes <joel.opensrc@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/1529981939-8231-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf fixes from Thomas Gleixner:
"A pile of perf updates:
Kernel side:
- Remove an incorrect warning in uprobe_init_insn() when
insn_get_length() fails. The error return code is handled at the
call site.
- Move the inline keyword to the right place in the perf ringbuffer
code to address a W=1 build warning.
Tooling:
perf stat:
- Fix metric column header display alignment
- Improve error messages for default attributes, providing better
output for error in command line.
- Add --interval-clear option, to provide a 'watch' like printing
perf script:
- Show hw-cache events too
perf c2c:
- Fix data dependency problem in layout of 'struct c2c_hist_entry'
Core:
- Do not blindly assume that 'struct perf_evsel' can be obtained via
a straight forward container_of() as there are call sites which
hand in a plain 'struct hist' which is not part of a container.
- Fix error index in the PMU event parser, so that error messages can
point to the problematic token"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Move the inline keyword at the beginning of the function declaration
uprobes/x86: Remove incorrect WARN_ON() in uprobe_init_insn()
perf script: Show hw-cache events
perf c2c: Keep struct hist_entry at the end of struct c2c_hist_entry
perf stat: Add event parsing error handling to add_default_attributes
perf stat: Allow to specify specific metric column len
perf stat: Fix metric column header display alignment
perf stat: Use only color_fprintf call in print_metric_only
perf stat: Add --interval-clear option
perf tools: Fix error index for pmu event parser
perf hists: Reimplement hists__has_callchains()
perf hists browser gtk: Use hist_entry__has_callchains()
perf hists: Make hist_entry__has_callchains() work with 'perf c2c'
perf hists: Save the callchain_size in struct hist_entry
Pull rseq fixes from Thomas Gleixer:
"A pile of rseq related fixups:
- Prevent infinite recursion when delivering SIGSEGV
- Remove the abort of rseq critical section on fork() as syscalls
inside rseq critical sections are explicitely forbidden. So no
point in doing the abort on the child.
- Align the rseq structure on 32 bytes in the ARM selftest code.
- Fix file permissions of the test script"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rseq: Avoid infinite recursion when delivering SIGSEGV
rseq/cleanup: Do not abort rseq c.s. in child on fork()
rseq/selftests/arm: Align 'struct rseq_cs' on 32 bytes
rseq/selftests: Make run_param_test.sh executable
Pull x86 fixes from Thomas Gleixner:
"A set of fixes for x86:
- Make Xen PV guest deal with speculative store bypass correctly
- Address more fallout from the 5-Level pagetable handling. Undo an
__initdata annotation to avoid section mismatch and malfunction
when post init code would touch the freed variable.
- Handle exception fixup in math_error() before calling notify_die().
The reverse call order incorrectly triggers notify_die() listeners
for soemthing which is handled correctly at the site which issues
the floating point instruction.
- Fix an off by one in the LLC topology calculation on AMD
- Handle non standard memory block sizes gracefully un UV platforms
- Plug a memory leak in the microcode loader
- Sanitize the purgatory build magic
- Add the x86 specific device tree bindings directory to the x86
MAINTAINER file patterns"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix 'no5lvl' handling
Revert "x86/mm: Mark __pgtable_l5_enabled __initdata"
x86/CPU/AMD: Fix LLC ID bit-shift calculation
MAINTAINERS: Add file patterns for x86 device tree bindings
x86/microcode/intel: Fix memleak in save_microcode_patch()
x86/platform/UV: Add kernel parameter to set memory block size
x86/platform/UV: Use new set memory block size function
x86/platform/UV: Add adjustable set memory block size function
x86/build: Remove unnecessary preparation for purgatory
Revert "kexec/purgatory: Add clean-up for purgatory directory"
x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths
x86: Call fixup_exception() before notify_die() in math_error()
Pull x86 pti fixes from Thomas Gleixner:
"Two small updates for the speculative distractions:
- Make it more clear to the compiler that array_index_mask_nospec()
is not subject for optimizations. It's not perfect, but ...
- Don't report XEN PV guests as vulnerable because their mitigation
state depends on the hypervisor. Report unknown and refer to the
hypervisor requirement"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/spectre_v1: Disable compiler optimizations over array_index_mask_nospec()
x86/pti: Don't report XenPV as vulnerable
Pull ras fixes from Thomas Gleixner:
"A set of fixes for RAS/MCE:
- Improve the error message when the kernel cannot recover from a MCE
so the maximum amount of information gets provided.
- Individually check MCE recovery features on SkyLake CPUs instead of
assuming none when the CAPID0 register does not advertise the
general ability for recovery.
- Prevent MCE to output inconsistent messages which first show an
error location and then claim that the source is unknown.
- Prevent overwriting MCi_STATUS in the attempt to gather more
information when a fatal MCE has alreay been detected. This leads
to empty status values in the printout and failing to react
promptly on the fatal event"
* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Fix incorrect "Machine check from unknown source" message
x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out()
x86/mce: Check for alternate indication of machine check recovery on Skylake
x86/mce: Improve error message when kernel cannot recover
early_identify_cpu() has to use early version of pgtable_l5_enabled()
that doesn't rely on cpu_feature_enabled().
Defining USE_EARLY_PGTABLE_L5 before all includes does the trick.
I lost the define in one of reworks of the original patch.
Fixes: 372fddf709 ("x86/mm: Introduce the 'no5lvl' kernel parameter")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180622220841.54135-3-kirill.shutemov@linux.intel.com
This reverts commit e4e961e36f.
We need to use early version of pgtable_l5_enabled() in
early_identify_cpu() as this code runs before cpu_feature_enabled() is
usable.
But it leads to section mismatch:
cpu_init()
load_mm_ldt()
ldt_slot_va()
LDT_BASE_ADDR
LDT_PGD_ENTRY
pgtable_l5_enabled()
__pgtable_l5_enabled
__pgtable_l5_enabled marked as __initdata, but cpu_init() is not __init.
It's fixable: early code can be isolated into a separate translation unit,
but such change collides with other work in the area. That's too much
hassle to save 4 bytes of memory.
Return __pgtable_l5_enabled back to be __ro_after_init.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180622220841.54135-2-kirill.shutemov@linux.intel.com
There is no simple yes/no test to determine if pseudo-locking was
successful. In order to test pseudo-locking we expose a debugfs file for
each pseudo-locked region that will record the latency of reading the
pseudo-locked memory at a stride of 32 bytes (hardcoded). These numbers
will give us an idea of locking was successful or not since they will
reflect cache hits and cache misses (hardware prefetching is disabled
during the test).
The new debugfs file "pseudo_lock_measure" will, when the
pseudo_lock_mem_latency tracepoint is enabled, record the latency of
accessing each cache line twice.
Kernel tracepoints offer us histograms (when CONFIG_HIST_TRIGGERS is
enabled) that is a simple way to visualize the memory access latency
and immediately see any cache misses. For example, the hist trigger
below before trigger of the measurement will display the memory access
latency and instances at each latency:
echo 'hist:keys=latency' > /sys/kernel/debug/tracing/events/resctrl/\
pseudo_lock_mem_latency/trigger
echo 1 > /sys/kernel/debug/tracing/events/resctrl/pseudo_lock_mem_latency/enable
echo 1 > /sys/kernel/debug/resctrl/<newlock>/pseudo_lock_measure
echo 0 > /sys/kernel/debug/tracing/events/resctrl/pseudo_lock_mem_latency/enable
cat /sys/kernel/debug/tracing/events/resctrl/pseudo_lock_mem_latency/hist
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/6b2ea76181099d1b79ccfa7d3be24497ab2d1a45.1529706536.git.reinette.chatre@intel.com
The user requests a pseudo-locked region by providing a schemata to a
resource group that is in the pseudo-locksetup mode. This is the
functionality that consumes the parsed user data and creates the
pseudo-locked region.
First, required information is deduced from user provided data.
This includes, how much memory does the requested bitmask represent,
which CPU the requested region is associated with, and what is the
cache line size of that cache (to learn the stride needed for locking).
Second, a contiguous block of memory matching the requested bitmask is
allocated.
Finally, pseudo-locking is performed. The resource group already has the
allocation that reflects the requested bitmask. With this class of service
active and interference minimized, the allocated memory is loaded into the
cache.
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/67391160bbf06143bc62d856d3d234eb152008b7.1529706536.git.reinette.chatre@intel.com
A pseudo-locked region does not have a class of service associated with
it and thus not tracked in the array of control values maintained as
part of the domain. Even so, when the user provides a new bitmask for
another resource group it needs to be checked for interference with
existing pseudo-locked regions.
Additionally only one pseudo-locked region can be created in any cache
hierarchy.
Introduce two utilities in support of above scenarios: (1) a utility
that can be used to test if a given capacity bitmask overlaps with any
pseudo-locked regions associated with a particular cache instance, (2) a
utility that can be used to test if a pseudo-locked region exists within
a particular cache hierarchy.
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/b8e31dbdcf22ddf71df46072647b47e7558abb32.1529706536.git.reinette.chatre@intel.com
The user can request entering pseudo-locksetup mode by writing
"pseudo-locksetup" to the mode file. Act on this request as well as
support switching from a pseudo-locksetup mode (before pseudo-locked
mode was entered). It is not supported to modify the mode once
pseudo-locked mode has been entered.
The schemata reflects the new mode by adding "uninitialized" to all
resources. The size resctrl file reports zero for all cache domains in
support of the uninitialized nature. Since there are no users of this
class of service its allocations can be ignored when searching for
appropriate default allocations for new resource groups. For the same
reason resource groups in pseudo-locksetup mode are not considered when
testing if new resource groups may overlap.
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/56f553334708022903c296284e62db3bbc1ff150.1529706536.git.reinette.chatre@intel.com
The locksetup mode is the way in which the user communicates that the
resource group will be used for a pseudo-locked region. Locksetup mode
should thus ensure that all restrictions on a resource group are met before
locksetup mode can be entered. The resource group should also be configured
to ensure that it cannot be modified in unsupported ways when a
pseudo-locked region.
Introduce the support where the request for entering locksetup mode can be
validated. This includes: CDP is not active, no cpus or tasks are assigned
to the resource group, monitoring is not in progress on the resource
group. Once the resource group is determined ready for a pseudo-locked
region it is configured to not allow future changes to these properties.
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/b120f71ced30116bcc6c6f651e8a7906ae6b903d.1529706536.git.reinette.chatre@intel.com
When a resource group is used for Cache Pseudo-Locking then the region of
cache ends up being orphaned with no class of service referring to it. The
resctrl files intended to manage how the classes of services are utilized
thus become irrelevant.
The fact that a resctrl file is not relevant can be communicated to the
user by setting all of its permissions to zero. That is, its read, write,
and execute permissions are unset for all users.
Introduce two utilities, rdtgroup_kn_mode_restrict() and
rdtgroup_kn_mode_restore(), that can be used to restrict and restore the
permissions of a file or directory belonging to a resource group.
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/7afdbf5551b2f93cd45d61fbf5e01d87331f529a.1529706536.git.reinette.chatre@intel.com
By default, if the opener has CAP_DAC_OVERRIDE, a kernfs file can be opened
regardless of RW permissions. Writing to a kernfs file will thus succeed
even if permissions are 0000.
It's required to restrict the actions that can be performed on a resource
group from userspace based on the mode of the resource group. This
restriction will be done through a modification of the file
permissions. That is, for example, if a resource group is locked then the
user cannot add tasks to the resource group.
For this restriction through file permissions to work it has to be ensured
that the permissions are always respected. To do so the resctrl filesystem
is created with the KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK flag that will result
in open(2) failing with -EACCESS regardless of CAP_DAC_OVERRIDE if the
permission does not have the respective read or write access.
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/26f4fc25f110bfc07c2d2c8b2c4ee904922fedf7.1529706536.git.reinette.chatre@intel.com
With cache regions now explicitly marked as "shareable" or "exclusive"
we would like to communicate to the user how portions of the cache
are used.
Introduce "bit_usage" that indicates for each resource
how portions of the cache are configured to be used.
To assist the user to distinguish whether the sharing is from software or
hardware we add the following annotation:
0 - currently unused
X - currently available for sharing and used by software and hardware
H - currently used by hardware only but available for software use
S - currently used and shareable by software only
E - currently used exclusively by one resource group
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/105d44c40e582c2b7e2dccf0ae247e5e61137d4b.1529706536.git.reinette.chatre@intel.com
