Changes in 4.9.319
x86/cpu: Add Elkhart Lake to Intel family
cpu/speculation: Add prototype for cpu_show_srbds()
x86/cpu: Add Jasper Lake to Intel family
x86/cpu: Add Cannonlake to Intel family
x86/CPU: Add Icelake model number
x86/CPU: Add more Icelake model numbers
x86/cpu: Add Comet Lake to the Intel CPU models header
x86/cpu: Add Lakefield, Alder Lake and Rocket Lake models to the to Intel CPU family
x86/cpu: Add another Alder Lake CPU to the Intel family
Documentation: Add documentation for Processor MMIO Stale Data
x86/speculation/mmio: Enumerate Processor MMIO Stale Data bug
x86/speculation: Add a common function for MD_CLEAR mitigation update
x86/speculation/mmio: Add mitigation for Processor MMIO Stale Data
x86/bugs: Group MDS, TAA & Processor MMIO Stale Data mitigations
x86/speculation/mmio: Enable CPU Fill buffer clearing on idle
x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale Data
x86/speculation/srbds: Update SRBDS mitigation selection
x86/speculation/mmio: Reuse SRBDS mitigation for SBDS
KVM: x86/speculation: Disable Fill buffer clear within guests
x86/speculation/mmio: Print SMT warning
Linux 4.9.319
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: If6e129957d24760e3f6a16c270bc8fb6c44446a3
commit 8d50cdf8b8341770bc6367bce40c0c1bb0e1d5b3 upstream
Add the sysfs reporting file for Processor MMIO Stale Data
vulnerability. It exposes the vulnerability and mitigation state similar
to the existing files for the other hardware vulnerabilities.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2accfa69050c2a0d6fc6106f609208b3e9622b26 upstream.
0-day is not happy that there is no prototype for cpu_show_srbds():
drivers/base/cpu.c:565:16: error: no previous prototype for 'cpu_show_srbds'
Fixes: 7e5b3c267d25 ("x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200617141410.93338-1-linux@roeck-us.net
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes in 4.9.202
kvm: mmu: Don't read PDPTEs when paging is not enabled
Bluetooth: hci_ldisc: Postpone HCI_UART_PROTO_READY bit set in hci_uart_set_proto()
MIPS: BCM63XX: fix switch core reset on BCM6368
usb: gadget: core: unmap request from DMA only if previously mapped
KVM: x86: use Intel speculation bugs and features as derived in generic x86 code
x86/msr: Add the IA32_TSX_CTRL MSR
x86/cpu: Add a helper function x86_read_arch_cap_msr()
x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default
x86/speculation/taa: Add mitigation for TSX Async Abort
x86/speculation/taa: Add sysfs reporting for TSX Async Abort
kvm/x86: Export MDS_NO=0 to guests when TSX is enabled
x86/tsx: Add "auto" option to the tsx= cmdline parameter
x86/speculation/taa: Add documentation for TSX Async Abort
x86/tsx: Add config options to set tsx=on|off|auto
x86/speculation/taa: Fix printing of TAA_MSG_SMT on IBRS_ALL CPUs
KVM: x86: simplify ept_misconfig
KVM: x86: extend usage of RET_MMIO_PF_* constants
kvm: Convert kvm_lock to a mutex
kvm: x86: Do not release the page inside mmu_set_spte()
KVM: x86: make FNAME(fetch) and __direct_map more similar
KVM: x86: remove now unneeded hugepage gfn adjustment
KVM: x86: change kvm_mmu_page_get_gfn BUG_ON to WARN_ON
KVM: x86: Add is_executable_pte()
KVM: x86: add tracepoints around __direct_map and FNAME(fetch)
KVM: vmx, svm: always run with EFER.NXE=1 when shadow paging is active
x86/bugs: Add ITLB_MULTIHIT bug infrastructure
cpu/speculation: Uninline and export CPU mitigations helpers
kvm: mmu: ITLB_MULTIHIT mitigation
kvm: Add helper function for creating VM worker threads
kvm: x86: mmu: Recovery of shattered NX large pages
Documentation: Add ITLB_MULTIHIT documentation
Linux 4.9.202
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 731dc9df975a5da21237a18c3384f811a7a41cc6 upstream.
A kernel module may need to check the value of the "mitigations=" kernel
command line parameter as part of its setup when the module needs
to perform software mitigations for a CPU flaw.
Uninline and export the helper functions surrounding the cpu_mitigations
enum to allow for their usage from a module.
Lastly, privatize the enum and cpu_mitigations variable since the value of
cpu_mitigations can be checked with the exported helper functions.
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit db4d30fbb71b47e4ecb11c4efa5d8aad4b03dfae upstream.
Some processors may incur a machine check error possibly resulting in an
unrecoverable CPU lockup when an instruction fetch encounters a TLB
multi-hit in the instruction TLB. This can occur when the page size is
changed along with either the physical address or cache type. The relevant
erratum can be found here:
https://bugzilla.kernel.org/show_bug.cgi?id=205195
There are other processors affected for which the erratum does not fully
disclose the impact.
This issue affects both bare-metal x86 page tables and EPT.
It can be mitigated by either eliminating the use of large pages or by
using careful TLB invalidations when changing the page size in the page
tables.
Just like Spectre, Meltdown, L1TF and MDS, a new bit has been allocated in
MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will be set on CPUs which
are mitigated against this issue.
Signed-off-by: Vineela Tummalapalli <vineela.tummalapalli@intel.com>
Co-developed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bwh: Backported to 4.9:
- No support for X86_VENDOR_HYGON, ATOM_AIRMONT_NP
- Adjust context, indentation]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes in 4.9.181
ipv6: Consider sk_bound_dev_if when binding a raw socket to an address
llc: fix skb leak in llc_build_and_send_ui_pkt()
net: fec: fix the clk mismatch in failed_reset path
net-gro: fix use-after-free read in napi_gro_frags()
net: stmmac: fix reset gpio free missing
usbnet: fix kernel crash after disconnect
tipc: Avoid copying bytes beyond the supplied data
bnxt_en: Fix aggregation buffer leak under OOM condition.
ipv4/igmp: fix another memory leak in igmpv3_del_delrec()
ipv4/igmp: fix build error if !CONFIG_IP_MULTICAST
net: dsa: mv88e6xxx: fix handling of upper half of STATS_TYPE_PORT
net: mvneta: Fix err code path of probe
net: mvpp2: fix bad MVPP2_TXQ_SCHED_TOKEN_CNTR_REG queue value
crypto: vmx - ghash: do nosimd fallback manually
xen/pciback: Don't disable PCI_COMMAND on PCI device reset.
Revert "tipc: fix modprobe tipc failed after switch order of device registration"
tipc: fix modprobe tipc failed after switch order of device registration
sparc64: Fix regression in non-hypervisor TLB flush xcall
include/linux/bitops.h: sanitize rotate primitives
xhci: update bounce buffer with correct sg num
xhci: Use %zu for printing size_t type
xhci: Convert xhci_handshake() to use readl_poll_timeout_atomic()
usb: xhci: avoid null pointer deref when bos field is NULL
usbip: usbip_host: fix BUG: sleeping function called from invalid context
usbip: usbip_host: fix stub_dev lock context imbalance regression
USB: Fix slab-out-of-bounds write in usb_get_bos_descriptor
USB: sisusbvga: fix oops in error path of sisusb_probe
USB: Add LPM quirk for Surface Dock GigE adapter
USB: rio500: refuse more than one device at a time
USB: rio500: fix memory leak in close after disconnect
media: usb: siano: Fix general protection fault in smsusb
media: usb: siano: Fix false-positive "uninitialized variable" warning
media: smsusb: better handle optional alignment
scsi: zfcp: fix missing zfcp_port reference put on -EBUSY from port_remove
scsi: zfcp: fix to prevent port_remove with pure auto scan LUNs (only sdevs)
Btrfs: fix race updating log root item during fsync
powerpc/perf: Fix MMCRA corruption by bhrb_filter
ALSA: hda/realtek - Set default power save node to 0
drm/nouveau/i2c: Disable i2c bus access after ->fini()
tty: serial: msm_serial: Fix XON/XOFF
tty: max310x: Fix external crystal register setup
memcg: make it work on sparse non-0-node systems
kernel/signal.c: trace_signal_deliver when signal_group_exit
docs: Fix conf.py for Sphinx 2.0
staging: vc04_services: prevent integer overflow in create_pagelist()
CIFS: cifs_read_allocate_pages: don't iterate through whole page array on ENOMEM
gcc-plugins: Fix build failures under Darwin host
drm/vmwgfx: Don't send drm sysfs hotplug events on initial master set
brcmfmac: add length checks in scheduled scan result handler
brcmfmac: assure SSID length from firmware is limited
brcmfmac: add subtype check for event handling in data path
binder: Replace "%p" with "%pK" for stable
binder: replace "%p" with "%pK"
fs: prevent page refcount overflow in pipe_buf_get
mm, gup: remove broken VM_BUG_ON_PAGE compound check for hugepages
mm, gup: ensure real head page is ref-counted when using hugepages
mm: prevent get_user_pages() from overflowing page refcount
mm: make page ref count overflow check tighter and more explicit
Revert "x86/build: Move _etext to actual end of .text"
efi/libstub: Unify command line param parsing
media: uvcvideo: Fix uvc_alloc_entity() allocation alignment
ethtool: fix potential userspace buffer overflow
neighbor: Call __ipv4_neigh_lookup_noref in neigh_xmit
net/mlx4_en: ethtool, Remove unsupported SFP EEPROM high pages query
net: rds: fix memory leak in rds_ib_flush_mr_pool
pktgen: do not sleep with the thread lock held.
ipv6: fix EFAULT on sendto with icmpv6 and hdrincl
ipv6: use READ_ONCE() for inet->hdrincl as in ipv4
Revert "fib_rules: fix error in backport of e9919a24d302 ("fib_rules: return 0...")"
Revert "fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied"
rcu: locking and unlocking need to always be at least barriers
parisc: Use implicit space register selection for loading the coherence index of I/O pdirs
fuse: fallocate: fix return with locked inode
x86/power: Fix 'nosmt' vs hibernation triple fault during resume
MIPS: pistachio: Build uImage.gz by default
Revert "MIPS: perf: ath79: Fix perfcount IRQ assignment"
genwqe: Prevent an integer overflow in the ioctl
drm/gma500/cdv: Check vbt config bits when detecting lvds panels
drm/radeon: prefer lower reference dividers
drm/i915: Fix I915_EXEC_RING_MASK
TTY: serial_core, add ->install
fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock
fuse: Add FOPEN_STREAM to use stream_open()
ipv4: Define __ipv4_neigh_lookup_noref when CONFIG_INET is disabled
ethtool: check the return value of get_regs_len
Linux 4.9.181
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit ec527c318036a65a083ef68d8ba95789d2212246 upstream.
As explained in
0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once")
we always, no matter what, have to bring up x86 HT siblings during boot at
least once in order to avoid first MCE bringing the system to its knees.
That means that whenever 'nosmt' is supplied on the kernel command-line,
all the HT siblings are as a result sitting in mwait or cpudile after
going through the online-offline cycle at least once.
This causes a serious issue though when a kernel, which saw 'nosmt' on its
commandline, is going to perform resume from hibernation: if the resume
from the hibernated image is successful, cr3 is flipped in order to point
to the address space of the kernel that is being resumed, which in turn
means that all the HT siblings are all of a sudden mwaiting on address
which is no longer valid.
That results in triple fault shortly after cr3 is switched, and machine
reboots.
Fix this by always waking up all the SMT siblings before initiating the
'restore from hibernation' process; this guarantees that all the HT
siblings will be properly carried over to the resumed kernel waiting in
resume_play_dead(), and acted upon accordingly afterwards, based on the
target kernel configuration.
Symmetricaly, the resumed kernel has to push the SMT siblings to mwait
again in case it has SMT disabled; this means it has to online all
the siblings when resuming (so that they come out of hlt) and offline
them again to let them reach mwait.
Cc: 4.19+ <stable@vger.kernel.org> # v4.19+
Debugged-by: Thomas Gleixner <tglx@linutronix.de>
Fixes: 0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes in 4.9.176
x86/MCE: Save microcode revision in machine check records
x86/cpufeatures: Hide AMD-specific speculation flags
x86/bugs: Add AMD's variant of SSB_NO
x86/bugs: Add AMD's SPEC_CTRL MSR usage
x86/bugs: Switch the selection of mitigation from CPU vendor to CPU features
x86/bugs: Fix the AMD SSBD usage of the SPEC_CTRL MSR
x86/microcode/intel: Add a helper which gives the microcode revision
x86/microcode/intel: Check microcode revision before updating sibling threads
x86/microcode: Make sure boot_cpu_data.microcode is up-to-date
x86/microcode: Update the new microcode revision unconditionally
x86/mm: Use WRITE_ONCE() when setting PTEs
bitops: avoid integer overflow in GENMASK(_ULL)
x86/speculation: Simplify the CPU bug detection logic
locking/atomics, asm-generic: Move some macros from <linux/bitops.h> to a new <linux/bits.h> file
x86/speculation: Remove SPECTRE_V2_IBRS in enum spectre_v2_mitigation
x86/cpu: Sanitize FAM6_ATOM naming
Documentation/l1tf: Fix small spelling typo
x86/speculation: Apply IBPB more strictly to avoid cross-process data leak
x86/speculation: Enable cross-hyperthread spectre v2 STIBP mitigation
x86/speculation: Propagate information about RSB filling mitigation to sysfs
x86/speculation/l1tf: Drop the swap storage limit restriction when l1tf=off
x86/speculation: Update the TIF_SSBD comment
x86/speculation: Clean up spectre_v2_parse_cmdline()
x86/speculation: Remove unnecessary ret variable in cpu_show_common()
x86/speculation: Move STIPB/IBPB string conditionals out of cpu_show_common()
x86/speculation: Disable STIBP when enhanced IBRS is in use
x86/speculation: Rename SSBD update functions
x86/speculation: Reorganize speculation control MSRs update
x86/Kconfig: Select SCHED_SMT if SMP enabled
sched: Add sched_smt_active()
x86/speculation: Rework SMT state change
x86/l1tf: Show actual SMT state
x86/speculation: Reorder the spec_v2 code
x86/speculation: Mark string arrays const correctly
x86/speculataion: Mark command line parser data __initdata
x86/speculation: Unify conditional spectre v2 print functions
x86/speculation: Add command line control for indirect branch speculation
x86/speculation: Prepare for per task indirect branch speculation control
x86/process: Consolidate and simplify switch_to_xtra() code
x86/speculation: Avoid __switch_to_xtra() calls
x86/speculation: Prepare for conditional IBPB in switch_mm()
x86/speculation: Split out TIF update
x86/speculation: Prepare arch_smt_update() for PRCTL mode
x86/speculation: Prevent stale SPEC_CTRL msr content
x86/speculation: Add prctl() control for indirect branch speculation
x86/speculation: Enable prctl mode for spectre_v2_user
x86/speculation: Add seccomp Spectre v2 user space protection mode
x86/speculation: Provide IBPB always command line options
kvm: x86: Report STIBP on GET_SUPPORTED_CPUID
x86/msr-index: Cleanup bit defines
x86/speculation: Consolidate CPU whitelists
x86/speculation/mds: Add basic bug infrastructure for MDS
x86/speculation/mds: Add BUG_MSBDS_ONLY
x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
x86/speculation/mds: Add mds_clear_cpu_buffers()
x86/speculation/mds: Clear CPU buffers on exit to user
x86/kvm/vmx: Add MDS protection when L1D Flush is not active
x86/speculation/mds: Conditionally clear CPU buffers on idle entry
x86/speculation/mds: Add mitigation control for MDS
x86/speculation/mds: Add sysfs reporting for MDS
x86/speculation/mds: Add mitigation mode VMWERV
Documentation: Move L1TF to separate directory
Documentation: Add MDS vulnerability documentation
x86/speculation/mds: Add mds=full,nosmt cmdline option
x86/speculation: Move arch_smt_update() call to after mitigation decisions
x86/speculation/mds: Add SMT warning message
x86/speculation/mds: Fix comment
x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
cpu/speculation: Add 'mitigations=' cmdline option
x86/speculation: Support 'mitigations=' cmdline option
x86/speculation/mds: Add 'mitigations=' support for MDS
x86/mds: Add MDSUM variant to the MDS documentation
Documentation: Correct the possible MDS sysfs values
x86/speculation/mds: Fix documentation typo
x86: stop exporting msr-index.h to userland
x86/cpu/bugs: Use __initconst for 'const' init data
Linux 4.9.176
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 8a4b06d391b0a42a373808979b5028f5c84d9c6a upstream.
Add the sysfs reporting file for MDS. It exposes the vulnerability and
mitigation state similar to the existing files for the other speculative
hardware vulnerabilities.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
[bwh: Backported to 4.9: test x86_hyper instead of using hypervisor_is_type()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes in 4.9.120
ext4: fix check to prevent initializing reserved inodes
tpm: fix race condition in tpm_common_write()
parisc: Enable CONFIG_MLONGCALLS by default
parisc: Define mb() and add memory barriers to assembler unlock sequences
kasan: add no_sanitize attribute for clang builds
Mark HI and TASKLET softirq synchronous
xen/netfront: don't cache skb_shinfo()
ACPI / LPSS: Add missing prv_offset setting for byt/cht PWM devices
scsi: sr: Avoid that opening a CD-ROM hangs with runtime power management enabled
init: rename and re-order boot_cpu_state_init()
root dentries need RCU-delayed freeing
make sure that __dentry_kill() always invalidates d_seq, unhashed or not
fix mntput/mntput race
fix __legitimize_mnt()/mntput() race
proc/sysctl: prune stale dentries during unregistering
proc/sysctl: Don't grab i_lock under sysctl_lock.
proc: Fix proc_sys_prune_dcache to hold a sb reference
IB/core: Make testing MR flags for writability a static inline function
IB/mlx4: Mark user MR as writable if actual virtual memory is writable
mtd: nand: qcom: Add a NULL check for devm_kasprintf()
IB/ocrdma: fix out of bounds access to local buffer
ARM: dts: imx6sx: fix irq for pcie bridge
x86/paravirt: Fix spectre-v2 mitigations for paravirt guests
x86/speculation: Protect against userspace-userspace spectreRSB
kprobes/x86: Fix %p uses in error messages
x86/irqflags: Provide a declaration for native_save_fl
x86/speculation/l1tf: Increase 32bit PAE __PHYSICAL_PAGE_SHIFT
mm: x86: move _PAGE_SWP_SOFT_DIRTY from bit 7 to bit 1
x86/speculation/l1tf: Change order of offset/type in swap entry
x86/speculation/l1tf: Protect swap entries against L1TF
x86/speculation/l1tf: Protect PROT_NONE PTEs against speculation
x86/speculation/l1tf: Make sure the first page is always reserved
x86/speculation/l1tf: Add sysfs reporting for l1tf
x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings
x86/speculation/l1tf: Limit swap file size to MAX_PA/2
x86/bugs: Move the l1tf function and define pr_fmt properly
x86/smp: Provide topology_is_primary_thread()
x86/topology: Provide topology_smt_supported()
cpu/hotplug: Make bringup/teardown of smp threads symmetric
cpu/hotplug: Split do_cpu_down()
cpu/hotplug: Provide knobs to control SMT
x86/cpu: Remove the pointless CPU printout
x86/cpu/AMD: Remove the pointless detect_ht() call
x86/cpu/common: Provide detect_ht_early()
x86/cpu/topology: Provide detect_extended_topology_early()
x86/cpu/intel: Evaluate smp_num_siblings early
x86/CPU/AMD: Do not check CPUID max ext level before parsing SMP info
x86/cpu/AMD: Evaluate smp_num_siblings early
x86/apic: Ignore secondary threads if nosmt=force
x86/speculation/l1tf: Extend 64bit swap file size limit
x86/cpufeatures: Add detection of L1D cache flush support.
x86/CPU/AMD: Move TOPOEXT reenablement before reading smp_num_siblings
x86/speculation/l1tf: Protect PAE swap entries against L1TF
x86/speculation/l1tf: Fix up pte->pfn conversion for PAE
Revert "x86/apic: Ignore secondary threads if nosmt=force"
cpu/hotplug: Boot HT siblings at least once
x86/KVM: Warn user if KVM is loaded SMT and L1TF CPU bug being present
x86/KVM/VMX: Add module argument for L1TF mitigation
x86/KVM/VMX: Add L1D flush algorithm
x86/KVM/VMX: Add L1D MSR based flush
x86/KVM/VMX: Add L1D flush logic
kvm: nVMX: Update MSR load counts on a VMCS switch
x86/KVM/VMX: Split the VMX MSR LOAD structures to have an host/guest numbers
x86/KVM/VMX: Add find_msr() helper function
x86/KVM/VMX: Separate the VMX AUTOLOAD guest/host number accounting
x86/KVM/VMX: Extend add_atomic_switch_msr() to allow VMENTER only MSRs
x86/KVM/VMX: Use MSR save list for IA32_FLUSH_CMD if required
cpu/hotplug: Online siblings when SMT control is turned on
x86/litf: Introduce vmx status variable
x86/kvm: Drop L1TF MSR list approach
x86/l1tf: Handle EPT disabled state proper
x86/kvm: Move l1tf setup function
x86/kvm: Add static key for flush always
x86/kvm: Serialize L1D flush parameter setter
x86/kvm: Allow runtime control of L1D flush
cpu/hotplug: Expose SMT control init function
cpu/hotplug: Set CPU_SMT_NOT_SUPPORTED early
x86/bugs, kvm: Introduce boot-time control of L1TF mitigations
Documentation: Add section about CPU vulnerabilities
x86/KVM/VMX: Initialize the vmx_l1d_flush_pages' content
Documentation/l1tf: Fix typos
cpu/hotplug: detect SMT disabled by BIOS
x86/KVM/VMX: Don't set l1tf_flush_l1d to true from vmx_l1d_flush()
x86/KVM/VMX: Replace 'vmx_l1d_flush_always' with 'vmx_l1d_flush_cond'
x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush()
x86/irq: Demote irq_cpustat_t::__softirq_pending to u16
x86/KVM/VMX: Introduce per-host-cpu analogue of l1tf_flush_l1d
x86: Don't include linux/irq.h from asm/hardirq.h
x86/irq: Let interrupt handlers set kvm_cpu_l1tf_flush_l1d
x86/KVM/VMX: Don't set l1tf_flush_l1d from vmx_handle_external_intr()
Documentation/l1tf: Remove Yonah processors from not vulnerable list
KVM: x86: Add a framework for supporting MSR-based features
KVM: SVM: Add MSR-based feature support for serializing LFENCE
KVM: X86: Introduce kvm_get_msr_feature()
KVM: X86: Allow userspace to define the microcode version
KVM: VMX: support MSR_IA32_ARCH_CAPABILITIES as a feature MSR
x86/speculation: Simplify sysfs report of VMX L1TF vulnerability
x86/speculation: Use ARCH_CAPABILITIES to skip L1D flush on vmentry
KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry
cpu/hotplug: Fix SMT supported evaluation
x86/speculation/l1tf: Invert all not present mappings
x86/speculation/l1tf: Make pmd/pud_mknotpresent() invert
x86/mm/pat: Make set_memory_np() L1TF safe
x86/mm/kmmio: Make the tracer robust against L1TF
tools headers: Synchronise x86 cpufeatures.h for L1TF additions
x86/microcode: Do not upload microcode if CPUs are offline
x86/microcode: Allow late microcode loading with SMT disabled
x86/smp: fix non-SMP broken build due to redefinition of apic_id_is_primary_thread
cpu/hotplug: Non-SMP machines do not make use of booted_once
x86/init: fix build with CONFIG_SWAP=n
x86/speculation/l1tf: Unbreak !__HAVE_ARCH_PFN_MODIFY_ALLOWED architectures
x86/cpu/amd: Limit cpu_core_id fixup to families older than F17h
x86/CPU/AMD: Have smp_num_siblings and cpu_llc_id always be present
Linux 4.9.120
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit bc2d8d262cba5736332cbc866acb11b1c5748aa9 upstream
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: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS")
Reported-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fee0aede6f4739c87179eca76136f83210953b86 upstream
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
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 05736e4ac13c08a4a9b1ef2de26dd31a32cbee57 upstream
Provide a command line and a sysfs knob to control SMT.
The command line options are:
'nosmt': Enumerate secondary threads, but do not online them
'nosmt=force': Ignore secondary threads completely during enumeration
via MP table and ACPI/MADT.
The sysfs control file has the following states (read/write):
'on': SMT is enabled. Secondary threads can be freely onlined
'off': SMT is disabled. Secondary threads, even if enumerated
cannot be onlined
'forceoff': SMT is permanentely disabled. Writes to the control
file are rejected.
'notsupported': SMT is not supported by the CPU
The command line option 'nosmt' sets the sysfs control to 'off'. This
can be changed to 'on' to reenable SMT during runtime.
The command line option 'nosmt=force' sets the sysfs control to
'forceoff'. This cannot be changed during runtime.
When SMT is 'on' and the control file is changed to 'off' then all online
secondary threads are offlined and attempts to online a secondary thread
later on are rejected.
When SMT is 'off' and the control file is changed to 'on' then secondary
threads can be onlined again. The 'off' -> 'on' transition does not
automatically online the secondary threads.
When the control file is set to 'forceoff', the behaviour is the same as
setting it to 'off', but the operation is irreversible and later writes to
the control file are rejected.
When the control status is 'notsupported' then writes to the control file
are rejected.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 17dbca119312b4e8173d4e25ff64262119fcef38 upstream
L1TF core kernel workarounds are cheap and normally always enabled, However
they still should be reported in sysfs if the system is vulnerable or
mitigated. Add the necessary CPU feature/bug bits.
- Extend the existing checks for Meltdowns to determine if the system is
vulnerable. All CPUs which are not vulnerable to Meltdown are also not
vulnerable to L1TF
- Check for 32bit non PAE and emit a warning as there is no practical way
for mitigation due to the limited physical address bits
- If the system has more than MAX_PA/2 physical memory the invert page
workarounds don't protect the system against the L1TF attack anymore,
because an inverted physical address will also point to valid
memory. Print a warning in this case and report that the system is
vulnerable.
Add a function which returns the PFN limit for the L1TF mitigation, which
will be used in follow up patches for sanity and range checks.
[ tglx: Renamed the CPU feature bit to L1TF_PTEINV ]
[ dwmw2: Backport to 4.9 (cpufeatures.h, E820) ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b5b1404d0815894de0690de8a1ab58269e56eae6 upstream.
This is purely a preparatory patch for upcoming changes during the 4.19
merge window.
We have a function called "boot_cpu_state_init()" that isn't really
about the bootup cpu state: that is done much earlier by the similarly
named "boot_cpu_init()" (note lack of "state" in name).
This function initializes some hotplug CPU state, and needs to run after
the percpu data has been properly initialized. It even has a comment to
that effect.
Except it _doesn't_ actually run after the percpu data has been properly
initialized. On x86 it happens to do that, but on at least arm and
arm64, the percpu base pointers are initialized by the arch-specific
'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init().
This had some unexpected results, and in particular we have a patch
pending for the merge window that did the obvious cleanup of using
'this_cpu_write()' in the cpu hotplug init code:
- per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE;
+ this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);
which is obviously the right thing to do. Except because of the
ordering issue, it actually failed miserably and unexpectedly on arm64.
So this just fixes the ordering, and changes the name of the function to
be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu
hotplug state, because the core CPU state was supposed to have already
been done earlier.
Marked for stable, since the (not yet merged) patch that will show this
problem is marked for stable.
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes in 4.9.102
usbip: usbip_host: refine probe and disconnect debug msgs to be useful
usbip: usbip_host: delete device from busid_table after rebind
usbip: usbip_host: run rebind from exit when module is removed
usbip: usbip_host: fix NULL-ptr deref and use-after-free errors
usbip: usbip_host: fix bad unlock balance during stub_probe()
ALSA: usb: mixer: volume quirk for CM102-A+/102S+
ALSA: hda: Add Lenovo C50 All in one to the power_save blacklist
ALSA: control: fix a redundant-copy issue
spi: pxa2xx: Allow 64-bit DMA
spi: bcm-qspi: Avoid setting MSPI_CDRAM_PCS for spi-nor master
spi: bcm-qspi: Always read and set BSPI_MAST_N_BOOT_CTRL
KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock
powerpc: Don't preempt_disable() in show_cpuinfo()
signals: avoid unnecessary taking of sighand->siglock
tracing/x86/xen: Remove zero data size trace events trace_xen_mmu_flush_tlb{_all}
netfilter: nf_tables: can't fail after linking rule into active rule list
i2c: designware: fix poll-after-enable regression
powerpc/powernv: Fix NVRAM sleep in invalid context when crashing
mm: don't allow deferred pages with NEED_PER_CPU_KM
s390/qdio: fix access to uninitialized qdio_q fields
s390/cpum_sf: ensure sample frequency of perf event attributes is non-zero
s390/qdio: don't release memory in qdio_setup_irq()
s390: remove indirect branch from do_softirq_own_stack
x86/pkeys: Override pkey when moving away from PROT_EXEC
x86/pkeys: Do not special case protection key 0
efi: Avoid potential crashes, fix the 'struct efi_pci_io_protocol_32' definition for mixed mode
ARM: 8771/1: kprobes: Prohibit kprobes on do_undefinstr
tick/broadcast: Use for_each_cpu() specially on UP kernels
ARM: 8769/1: kprobes: Fix to use get_kprobe_ctlblk after irq-disabed
ARM: 8770/1: kprobes: Prohibit probing on optimized_callback
ARM: 8772/1: kprobes: Prohibit kprobes on get_user functions
Btrfs: fix xattr loss after power failure
btrfs: fix crash when trying to resume balance without the resume flag
x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under Xen
btrfs: fix reading stale metadata blocks after degraded raid1 mounts
x86/nospec: Simplify alternative_msr_write()
x86/bugs: Concentrate bug detection into a separate function
x86/bugs: Concentrate bug reporting into a separate function
x86/bugs: Read SPEC_CTRL MSR during boot and re-use reserved bits
x86/bugs, KVM: Support the combination of guest and host IBRS
x86/bugs: Expose /sys/../spec_store_bypass
x86/cpufeatures: Add X86_FEATURE_RDS
x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigation
x86/bugs/intel: Set proper CPU features and setup RDS
x86/bugs: Whitelist allowed SPEC_CTRL MSR values
x86/bugs/AMD: Add support to disable RDS on Fam[15,16,17]h if requested
x86/KVM/VMX: Expose SPEC_CTRL Bit(2) to the guest
x86/speculation: Create spec-ctrl.h to avoid include hell
prctl: Add speculation control prctls
x86/process: Optimize TIF checks in __switch_to_xtra()
x86/process: Correct and optimize TIF_BLOCKSTEP switch
x86/process: Optimize TIF_NOTSC switch
x86/process: Allow runtime control of Speculative Store Bypass
x86/speculation: Add prctl for Speculative Store Bypass mitigation
nospec: Allow getting/setting on non-current task
proc: Provide details on speculation flaw mitigations
seccomp: Enable speculation flaw mitigations
x86/bugs: Make boot modes __ro_after_init
prctl: Add force disable speculation
seccomp: Use PR_SPEC_FORCE_DISABLE
seccomp: Add filter flag to opt-out of SSB mitigation
seccomp: Move speculation migitation control to arch code
x86/speculation: Make "seccomp" the default mode for Speculative Store Bypass
x86/bugs: Rename _RDS to _SSBD
proc: Use underscores for SSBD in 'status'
Documentation/spec_ctrl: Do some minor cleanups
x86/bugs: Fix __ssb_select_mitigation() return type
x86/bugs: Make cpu_show_common() static
x86/bugs: Fix the parameters alignment and missing void
x86/cpu: Make alternative_msr_write work for 32-bit code
KVM: SVM: Move spec control call after restore of GS
x86/speculation: Use synthetic bits for IBRS/IBPB/STIBP
x86/cpufeatures: Disentangle MSR_SPEC_CTRL enumeration from IBRS
x86/cpufeatures: Disentangle SSBD enumeration
x86/cpu/AMD: Fix erratum 1076 (CPB bit)
x86/cpufeatures: Add FEATURE_ZEN
x86/speculation: Handle HT correctly on AMD
x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRL
x86/speculation: Add virtualized speculative store bypass disable support
x86/speculation: Rework speculative_store_bypass_update()
x86/bugs: Unify x86_spec_ctrl_{set_guest,restore_host}
x86/bugs: Expose x86_spec_ctrl_base directly
x86/bugs: Remove x86_spec_ctrl_set()
x86/bugs: Rework spec_ctrl base and mask logic
x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFG
KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBD
x86/bugs: Rename SSBD_NO to SSB_NO
Linux 4.9.102
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit c456442cd3a59eeb1d60293c26cbe2ff2c4e42cf upstream
Add the sysfs file for the new vulerability. It does not do much except
show the words 'Vulnerable' for recent x86 cores.
Intel cores prior to family 6 are known not to be vulnerable, and so are
some Atoms and some Xeon Phi.
It assumes that older Cyrix, Centaur, etc. cores are immune.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes in 4.9.77
dm bufio: fix shrinker scans when (nr_to_scan < retain_target)
mac80211: Add RX flag to indicate ICV stripped
ath10k: rebuild crypto header in rx data frames
KVM: Fix stack-out-of-bounds read in write_mmio
can: gs_usb: fix return value of the "set_bittiming" callback
IB/srpt: Disable RDMA access by the initiator
MIPS: Validate PR_SET_FP_MODE prctl(2) requests against the ABI of the task
MIPS: Factor out NT_PRFPREG regset access helpers
MIPS: Guard against any partial write attempt with PTRACE_SETREGSET
MIPS: Consistently handle buffer counter with PTRACE_SETREGSET
MIPS: Fix an FCSR access API regression with NT_PRFPREG and MSA
MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET
MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses
kvm: vmx: Scrub hardware GPRs at VM-exit
platform/x86: wmi: Call acpi_wmi_init() later
x86/acpi: Handle SCI interrupts above legacy space gracefully
ALSA: pcm: Remove incorrect snd_BUG_ON() usages
ALSA: pcm: Add missing error checks in OSS emulation plugin builder
ALSA: pcm: Abort properly at pending signal in OSS read/write loops
ALSA: pcm: Allow aborting mutex lock at OSS read/write loops
ALSA: aloop: Release cable upon open error path
ALSA: aloop: Fix inconsistent format due to incomplete rule
ALSA: aloop: Fix racy hw constraints adjustment
x86/acpi: Reduce code duplication in mp_override_legacy_irq()
zswap: don't param_set_charp while holding spinlock
lan78xx: use skb_cow_head() to deal with cloned skbs
sr9700: use skb_cow_head() to deal with cloned skbs
smsc75xx: use skb_cow_head() to deal with cloned skbs
cx82310_eth: use skb_cow_head() to deal with cloned skbs
xhci: Fix ring leak in failure path of xhci_alloc_virt_device()
8021q: fix a memory leak for VLAN 0 device
ip6_tunnel: disable dst caching if tunnel is dual-stack
net: core: fix module type in sock_diag_bind
RDS: Heap OOB write in rds_message_alloc_sgs()
RDS: null pointer dereference in rds_atomic_free_op
sh_eth: fix TSU resource handling
sh_eth: fix SH7757 GEther initialization
net: stmmac: enable EEE in MII, GMII or RGMII only
ipv6: fix possible mem leaks in ipv6_make_skb()
ethtool: do not print warning for applications using legacy API
mlxsw: spectrum_router: Fix NULL pointer deref
net/sched: Fix update of lastuse in act modules implementing stats_update
crypto: algapi - fix NULL dereference in crypto_remove_spawns()
rbd: set max_segments to USHRT_MAX
x86/microcode/intel: Extend BDW late-loading with a revision check
KVM: x86: Add memory barrier on vmcs field lookup
drm/vmwgfx: Potential off by one in vmw_view_add()
kaiser: Set _PAGE_NX only if supported
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
bpf: move fixup_bpf_calls() function
bpf: refactor fixup_bpf_calls()
bpf: prevent out-of-bounds speculation
bpf, array: fix overflow in max_entries and undefined behavior in index_mask
USB: serial: cp210x: add IDs for LifeScan OneTouch Verio IQ
USB: serial: cp210x: add new device ID ELV ALC 8xxx
usb: misc: usb3503: make sure reset is low for at least 100us
USB: fix usbmon BUG trigger
usbip: remove kernel addresses from usb device and urb debug msgs
usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input
usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer buffer
staging: android: ashmem: fix a race condition in ASHMEM_SET_SIZE ioctl
Bluetooth: Prevent stack info leak from the EFS element.
uas: ignore UAS for Norelsys NS1068(X) chips
e1000e: Fix e1000_check_for_copper_link_ich8lan return value.
x86/Documentation: Add PTI description
x86/cpu: Factor out application of forced CPU caps
x86/cpufeatures: Make CPU bugs sticky
x86/cpufeatures: Add X86_BUG_CPU_INSECURE
x86/pti: Rename BUG_CPU_INSECURE to BUG_CPU_MELTDOWN
x86/cpufeatures: Add X86_BUG_SPECTRE_V[12]
x86/cpu: Merge bugs.c and bugs_64.c
sysfs/cpu: Add vulnerability folder
x86/cpu: Implement CPU vulnerabilites sysfs functions
x86/cpu/AMD: Make LFENCE a serializing instruction
x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
sysfs/cpu: Fix typos in vulnerability documentation
x86/alternatives: Fix optimize_nops() checking
x86/alternatives: Add missing '\n' at end of ALTERNATIVE inline asm
x86/mm/32: Move setup_clear_cpu_cap(X86_FEATURE_PCID) earlier
objtool, modules: Discard objtool annotation sections for modules
objtool: Detect jumps to retpoline thunks
objtool: Allow alternatives to be ignored
x86/asm: Use register variable to get stack pointer value
x86/retpoline: Add initial retpoline support
x86/spectre: Add boot time option to select Spectre v2 mitigation
x86/retpoline/crypto: Convert crypto assembler indirect jumps
x86/retpoline/entry: Convert entry assembler indirect jumps
x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
x86/retpoline/hyperv: Convert assembler indirect jumps
x86/retpoline/xen: Convert Xen hypercall indirect jumps
x86/retpoline/checksum32: Convert assembler indirect jumps
x86/retpoline/irq32: Convert assembler indirect jumps
x86/retpoline: Fill return stack buffer on vmexit
selftests/x86: Add test_vsyscall
x86/retpoline: Remove compile time warning
objtool: Fix retpoline support for pre-ORC objtool
x86/pti/efi: broken conversion from efi to kernel page table
Linux 4.9.77
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Move the x86_64 idle notifiers originally by Andi Kleen and Venkatesh
Pallipadi to generic.
Change-Id: Idf29cda15be151f494ff245933c12462643388d5
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
commit 777c6e0daebb3fcefbbd6f620410a946b07ef6d0 upstream.
Yu Zhao has noticed that __unregister_cpu_notifier only unregisters its
notifiers when HOTPLUG_CPU=y while the registration might succeed even
when HOTPLUG_CPU=n if MODULE is enabled. This means that e.g. zswap
might keep a stale notifier on the list on the manual clean up during
the pool tear down and thus corrupt the list. Resulting in the following
[ 144.964346] BUG: unable to handle kernel paging request at ffff880658a2be78
[ 144.971337] IP: [<ffffffffa290b00b>] raw_notifier_chain_register+0x1b/0x40
<snipped>
[ 145.122628] Call Trace:
[ 145.125086] [<ffffffffa28e5cf8>] __register_cpu_notifier+0x18/0x20
[ 145.131350] [<ffffffffa2a5dd73>] zswap_pool_create+0x273/0x400
[ 145.137268] [<ffffffffa2a5e0fc>] __zswap_param_set+0x1fc/0x300
[ 145.143188] [<ffffffffa2944c1d>] ? trace_hardirqs_on+0xd/0x10
[ 145.149018] [<ffffffffa2908798>] ? kernel_param_lock+0x28/0x30
[ 145.154940] [<ffffffffa2a3e8cf>] ? __might_fault+0x4f/0xa0
[ 145.160511] [<ffffffffa2a5e237>] zswap_compressor_param_set+0x17/0x20
[ 145.167035] [<ffffffffa2908d3c>] param_attr_store+0x5c/0xb0
[ 145.172694] [<ffffffffa290848d>] module_attr_store+0x1d/0x30
[ 145.178443] [<ffffffffa2b2b41f>] sysfs_kf_write+0x4f/0x70
[ 145.183925] [<ffffffffa2b2a5b9>] kernfs_fop_write+0x149/0x180
[ 145.189761] [<ffffffffa2a99248>] __vfs_write+0x18/0x40
[ 145.194982] [<ffffffffa2a9a412>] vfs_write+0xb2/0x1a0
[ 145.200122] [<ffffffffa2a9a732>] SyS_write+0x52/0xa0
[ 145.205177] [<ffffffffa2ff4d97>] entry_SYSCALL_64_fastpath+0x12/0x17
This can be even triggered manually by changing
/sys/module/zswap/parameters/compressor multiple times.
Fix this issue by making unregister APIs symmetric to the register so
there are no surprises.
Fixes: 47e627bc8c ("[PATCH] hotplug: Allow modules to use the cpu hotplug notifiers even if !CONFIG_HOTPLUG_CPU")
Reported-and-tested-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Streetman <ddstreet@ieee.org>
Link: http://lkml.kernel.org/r/20161207135438.4310-1-mhocko@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull CPU hotplug updates from Thomas Gleixner:
"Yet another batch of cpu hotplug core updates and conversions:
- Provide core infrastructure for multi instance drivers so the
drivers do not have to keep custom lists.
- Convert custom lists to the new infrastructure. The block-mq custom
list conversion comes through the block tree and makes the diffstat
tip over to more lines removed than added.
- Handle unbalanced hotplug enable/disable calls more gracefully.
- Remove the obsolete CPU_STARTING/DYING notifier support.
- Convert another batch of notifier users.
The relayfs changes which conflicted with the conversion have been
shipped to me by Andrew.
The remaining lot is targeted for 4.10 so that we finally can remove
the rest of the notifiers"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
cpufreq: Fix up conversion to hotplug state machine
blk/mq: Reserve hotplug states for block multiqueue
x86/apic/uv: Convert to hotplug state machine
s390/mm/pfault: Convert to hotplug state machine
mips/loongson/smp: Convert to hotplug state machine
mips/octeon/smp: Convert to hotplug state machine
fault-injection/cpu: Convert to hotplug state machine
padata: Convert to hotplug state machine
cpufreq: Convert to hotplug state machine
ACPI/processor: Convert to hotplug state machine
virtio scsi: Convert to hotplug state machine
oprofile/timer: Convert to hotplug state machine
block/softirq: Convert to hotplug state machine
lib/irq_poll: Convert to hotplug state machine
x86/microcode: Convert to hotplug state machine
sh/SH-X3 SMP: Convert to hotplug state machine
ia64/mca: Convert to hotplug state machine
ARM/OMAP/wakeupgen: Convert to hotplug state machine
ARM/shmobile: Convert to hotplug state machine
arm64/FP/SIMD: Convert to hotplug state machine
...
disable_nonboot_cpus() assumes that the lowest numbered online CPU is
the boot CPU, and that this is the correct CPU to run any power
management code on.
On x86 this is always correct, as CPU0 cannot (easily) by taken offline.
On arm64 CPU0 can be taken offline. For hibernate/resume this means we
may hibernate on a CPU other than CPU0. If the system is rebooted with
kexec 'CPU0' will be assigned to a different physical CPU. This
complicates hibernate/resume as now we can't trust the CPU numbers.
Arch code can find the correct physical CPU, and ensure it is online
before resume from hibernate begins, but also needs to influence
disable_nonboot_cpus()s choice of CPU.
Rename disable_nonboot_cpus() as freeze_secondary_cpus() and add an
argument indicating which CPU should be left standing. Follow the logic
in migrate_to_reboot_cpu() to use the lowest numbered online CPU if the
requested CPU is not online.
Add disable_nonboot_cpus() as an inline function that has the existing
behaviour.
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now that we reduced everything into single notifiers, it's simple to move them
into the hotplug state machine space.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We can maintain the ordering of the scheduler cpu hotplug functionality nicely
in one notifer. Get rid of the maze.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Now that synchronize_sched_expedited() no longer uses it, there are
no users of try_get_online_cpus() in mainline. This commit therefore
removes it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Using __printf attributes helps to detect several format string issues
at compile time (even though -Wformat-security is currently disabled in
Makefile). For example it can detect when formatting a pointer as a
number, like the issue fixed in commit a3fa71c40f ("wl18xx: show
rx_frames_per_rates as an array as it really is"), or when the arguments
do not match the format string, c.f. for example commit 5ce1aca814
("reiserfs: fix __RASSERT format string").
To prevent similar bugs in the future, add a __printf attribute to every
function prototype which needs one in include/linux/ and lib/. These
functions were mostly found by using gcc's -Wsuggest-attribute=format
flag.
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, smpboot_unpark_threads() is invoked before the incoming CPU
has been added to the scheduler's runqueue structures. This might
potentially cause the unparked kthread to run on the wrong CPU, since the
correct CPU isn't fully set up yet.
That causes a sporadic, hard to debug boot crash triggering on some
systems, reported by Borislav Petkov, and bisected down to:
2a442c9c64 ("x86: Use common outgoing-CPU-notification code")
This patch places smpboot_unpark_threads() in a CPU hotplug
notifier with priority set so that these kthreads are unparked just after
the CPU has been added to the runqueues.
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit informs RCU of an outgoing CPU just before that CPU invokes
arch_cpu_idle_dead() during its last pass through the idle loop (via a
new CPU_DYING_IDLE notifier value). This change means that RCU need not
deal with outgoing CPUs passing through the scheduler after informing
RCU that they are no longer online. Note that removing the CPU from
the rcu_node ->qsmaskinit bit masks is done at CPU_DYING_IDLE time,
and orphaning callbacks is still done at CPU_DEAD time, the reason being
that at CPU_DEAD time we have another CPU that can adopt them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
RCU ignores offlined CPUs, so they cannot safely run RCU read-side code.
(They -can- use SRCU, but not RCU.) This means that any use of RCU
during or after the call to arch_cpu_idle_dead(). Unfortunately,
commit 2ed53c0d6c added a complete() call, which will contain RCU
read-side critical sections if there is a task waiting to be awakened.
Which, as it turns out, there almost never is. In my qemu/KVM testing,
the to-be-awakened task is not yet asleep more than 99.5% of the time.
In current mainline, failure is even harder to reproduce, requiring a
virtualized environment that delays the outgoing CPU by at least three
jiffies between the time it exits its stop_machine() task at CPU_DYING
time and the time it calls arch_cpu_idle_dead() from the idle loop.
However, this problem really can occur, especially in virtualized
environments, and therefore really does need to be fixed
This suggests moving back to the polling loop, but using a much shorter
wait, with gentle exponential backoff instead of the old 100-millisecond
wait. Most of the time, the loop will exit without waiting at all,
and almost all of the remaining uses will wait only five microseconds.
If the outgoing CPU is preempted, a loop will wait one jiffy, then
increase the wait by a factor of 11/10ths, rounding up. As before, there
is a five-second timeout.
This commit therefore provides common-code infrastructure to do the
dying-to-surviving CPU handoff in a safe manner. This code also
provides an indication at CPU-online of whether the CPU to be onlined
previously timed out on offline. The new cpu_check_up_prepare() function
returns -EBUSY if this CPU previously took more than five seconds to
go offline, or -EAGAIN if it has not yet managed to go offline. The
rationale for -EAGAIN is that it might still be preempted, so an additional
wait might well find it correctly offlined. Architecture-specific code
can decide how to handle these conditions. Systems in which CPUs take
themselves completely offline might respond to an -EBUSY return as if
it was a zero (success) return. Systems in which the surviving CPU must
take some action might take it at this time, or might simply mark the
other CPU as unusable.
Note that architectures that take the easy way out and simply pass the
-EBUSY and -EAGAIN upwards will change the sysfs API.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <linux-api@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
[ paulmck: Fixed state machine for architectures that don't check earlier
CPU-hotplug results as suggested by James Hogan. ]
This patch adds a new function to create per-cpu devices.
This helps in:
1. reusing the device infrastructure to create any cpu related
attributes and corresponding sysfs instead of creating and
dealing with raw kobjects directly
2. retaining the legacy path(/sys/devices/system/cpu/..) to support
existing sysfs ABI
3. avoiding to create links in the bus directory pointing to the
device as there would be per-cpu instance of these devices with
the same name since dev->bus is not populated to cpu_sysbus on
purpose
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the expedited grace-period primitives do get_online_cpus().
This greatly simplifies their implementation, but means that calls
to them holding locks that are acquired by CPU-hotplug notifiers (to
say nothing of calls to these primitives from CPU-hotplug notifiers)
can deadlock. But this is starting to become inconvenient, as can be
seen here: https://lkml.org/lkml/2014/8/5/754. The problem in this
case is that some developers need to acquire a mutex from a CPU-hotplug
notifier, but also need to hold it across a synchronize_rcu_expedited().
As noted above, this currently results in deadlock.
This commit avoids the deadlock and retains the simplicity by creating
a try_get_online_cpus(), which returns false if the get_online_cpus()
reference count could not immediately be incremented. If a call to
try_get_online_cpus() returns true, the expedited primitives operate as
before. If a call returns false, the expedited primitives fall back to
normal grace-period operations. This falling back of course results in
increased grace-period latency, but only during times when CPU hotplug
operations are actually in flight. The effect should therefore be
negligible during normal operation.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Tested-by: Lan Tianyu <tianyu.lan@intel.com>
After all architectures were converted to the generic idle framework,
commit d190e8195b ("idle: Remove GENERIC_IDLE_LOOP config switch")
removed the last caller of cpu_idle(). The forward declarations in
header files were forgotten.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
