15131 Commits

Author SHA1 Message Date
Thomas Gleixner
22dd836508 x86/speculation/mds: Add mitigation mode VMWERV
In virtualized environments it can happen that the host has the microcode
update which utilizes the VERW instruction to clear CPU buffers, but the
hypervisor is not yet updated to expose the X86_FEATURE_MD_CLEAR CPUID bit
to guests.

Introduce an internal mitigation mode VMWERV which enables the invocation
of the CPU buffer clearing even if X86_FEATURE_MD_CLEAR is not set. If the
system has no updated microcode this results in a pointless execution of
the VERW instruction wasting a few CPU cycles. If the microcode is updated,
but not exposed to a guest then the CPU buffers will be cleared.

That said: Virtual Machines Will Eventually Receive Vaccine

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:15 +01:00
Thomas Gleixner
8a4b06d391 x86/speculation/mds: Add sysfs reporting for MDS
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>
2019-03-06 21:52:14 +01:00
Thomas Gleixner
bc1241700a x86/speculation/mds: Add mitigation control for MDS
Now that the mitigations are in place, add a command line parameter to
control the mitigation, a mitigation selector function and a SMT update
mechanism.

This is the minimal straight forward initial implementation which just
provides an always on/off mode. The command line parameter is:

  mds=[full|off]

This is consistent with the existing mitigations for other speculative
hardware vulnerabilities.

The idle invocation is dynamically updated according to the SMT state of
the system similar to the dynamic update of the STIBP mitigation. The idle
mitigation is limited to CPUs which are only affected by MSBDS and not any
other variant, because the other variants cannot be mitigated on SMT
enabled systems.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:14 +01:00
Thomas Gleixner
07f07f55a2 x86/speculation/mds: Conditionally clear CPU buffers on idle entry
Add a static key which controls the invocation of the CPU buffer clear
mechanism on idle entry. This is independent of other MDS mitigations
because the idle entry invocation to mitigate the potential leakage due to
store buffer repartitioning is only necessary on SMT systems.

Add the actual invocations to the different halt/mwait variants which
covers all usage sites. mwaitx is not patched as it's not available on
Intel CPUs.

The buffer clear is only invoked before entering the C-State to prevent
that stale data from the idling CPU is spilled to the Hyper-Thread sibling
after the Store buffer got repartitioned and all entries are available to
the non idle sibling.

When coming out of idle the store buffer is partitioned again so each
sibling has half of it available. Now CPU which returned from idle could be
speculatively exposed to contents of the sibling, but the buffers are
flushed either on exit to user space or on VMENTER.

When later on conditional buffer clearing is implemented on top of this,
then there is no action required either because before returning to user
space the context switch will set the condition flag which causes a flush
on the return to user path.

Note, that the buffer clearing on idle is only sensible on CPUs which are
solely affected by MSBDS and not any other variant of MDS because the other
MDS variants cannot be mitigated when SMT is enabled, so the buffer
clearing on idle would be a window dressing exercise.

This intentionally does not handle the case in the acpi/processor_idle
driver which uses the legacy IO port interface for C-State transitions for
two reasons:

 - The acpi/processor_idle driver was replaced by the intel_idle driver
   almost a decade ago. Anything Nehalem upwards supports it and defaults
   to that new driver.

 - The legacy IO port interface is likely to be used on older and therefore
   unaffected CPUs or on systems which do not receive microcode updates
   anymore, so there is no point in adding that.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:13 +01:00
Thomas Gleixner
650b68a062 x86/kvm/vmx: Add MDS protection when L1D Flush is not active
CPUs which are affected by L1TF and MDS mitigate MDS with the L1D Flush on
VMENTER when updated microcode is installed.

If a CPU is not affected by L1TF or if the L1D Flush is not in use, then
MDS mitigation needs to be invoked explicitly.

For these cases, follow the host mitigation state and invoke the MDS
mitigation before VMENTER.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:13 +01:00
Thomas Gleixner
04dcbdb805 x86/speculation/mds: Clear CPU buffers on exit to user
Add a static key which controls the invocation of the CPU buffer clear
mechanism on exit to user space and add the call into
prepare_exit_to_usermode() and do_nmi() right before actually returning.

Add documentation which kernel to user space transition this covers and
explain why some corner cases are not mitigated.

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: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:13 +01:00
Thomas Gleixner
e261f209c3 x86/speculation/mds: Add BUG_MSBDS_ONLY
This bug bit is set on CPUs which are only affected by Microarchitectural
Store Buffer Data Sampling (MSBDS) and not by any other MDS variant.

This is important because the Store Buffers are partitioned between
Hyper-Threads so cross thread forwarding is not possible. But if a thread
enters or exits a sleep state the store buffer is repartitioned which can
expose data from one thread to the other. This transition can be mitigated.

That means that for CPUs which are only affected by MSBDS SMT can be
enabled, if the CPU is not affected by other SMT sensitive vulnerabilities,
e.g. L1TF. The XEON PHI variants fall into that category. Also the
Silvermont/Airmont ATOMs, but for them it's not really relevant as they do
not support SMT, but mark them for completeness sake.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:11 +01:00
Andi Kleen
ed5194c273 x86/speculation/mds: Add basic bug infrastructure for MDS
Microarchitectural Data Sampling (MDS), is a class of side channel attacks
on internal buffers in Intel CPUs. The variants are:

 - Microarchitectural Store Buffer Data Sampling (MSBDS) (CVE-2018-12126)
 - Microarchitectural Fill Buffer Data Sampling (MFBDS) (CVE-2018-12130)
 - Microarchitectural Load Port Data Sampling (MLPDS) (CVE-2018-12127)

MSBDS leaks Store Buffer Entries which can be speculatively forwarded to a
dependent load (store-to-load forwarding) as an optimization. The forward
can also happen to a faulting or assisting load operation for a different
memory address, which can be exploited under certain conditions. Store
buffers are partitioned between Hyper-Threads so cross thread forwarding is
not possible. But if a thread enters or exits a sleep state the store
buffer is repartitioned which can expose data from one thread to the other.

MFBDS leaks Fill Buffer Entries. Fill buffers are used internally to manage
L1 miss situations and to hold data which is returned or sent in response
to a memory or I/O operation. Fill buffers can forward data to a load
operation and also write data to the cache. When the fill buffer is
deallocated it can retain the stale data of the preceding operations which
can then be forwarded to a faulting or assisting load operation, which can
be exploited under certain conditions. Fill buffers are shared between
Hyper-Threads so cross thread leakage is possible.

MLDPS leaks Load Port Data. Load ports are used to perform load operations
from memory or I/O. The received data is then forwarded to the register
file or a subsequent operation. In some implementations the Load Port can
contain stale data from a previous operation which can be forwarded to
faulting or assisting loads under certain conditions, which again can be
exploited eventually. Load ports are shared between Hyper-Threads so cross
thread leakage is possible.

All variants have the same mitigation for single CPU thread case (SMT off),
so the kernel can treat them as one MDS issue.

Add the basic infrastructure to detect if the current CPU is affected by
MDS.

[ tglx: Rewrote changelog ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:11 +01:00
Thomas Gleixner
36ad35131a x86/speculation: Consolidate CPU whitelists
The CPU vulnerability whitelists have some overlap and there are more
whitelists coming along.

Use the driver_data field in the x86_cpu_id struct to denote the
whitelisted vulnerabilities and combine all whitelists into one.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
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>
2019-03-06 21:52:10 +01:00
Linus Torvalds
8dcd175bc3 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - a few misc things

 - ocfs2 updates

 - most of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (159 commits)
  tools/testing/selftests/proc/proc-self-syscall.c: remove duplicate include
  proc: more robust bulk read test
  proc: test /proc/*/maps, smaps, smaps_rollup, statm
  proc: use seq_puts() everywhere
  proc: read kernel cpu stat pointer once
  proc: remove unused argument in proc_pid_lookup()
  fs/proc/thread_self.c: code cleanup for proc_setup_thread_self()
  fs/proc/self.c: code cleanup for proc_setup_self()
  proc: return exit code 4 for skipped tests
  mm,mremap: bail out earlier in mremap_to under map pressure
  mm/sparse: fix a bad comparison
  mm/memory.c: do_fault: avoid usage of stale vm_area_struct
  writeback: fix inode cgroup switching comment
  mm/huge_memory.c: fix "orig_pud" set but not used
  mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC
  mm/memcontrol.c: fix bad line in comment
  mm/cma.c: cma_declare_contiguous: correct err handling
  mm/page_ext.c: fix an imbalance with kmemleak
  mm/compaction: pass pgdat to too_many_isolated() instead of zone
  mm: remove zone_lru_lock() function, access ->lru_lock directly
  ...
2019-03-06 10:31:36 -08:00
Linus Torvalds
6ea98b4baa Merge branch 'x86-alternatives-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 alternative instruction updates from Ingo Molnar:
 "Small RDTSCP opimization, enabled by the newly added ALTERNATIVE_3(),
  and other small improvements"

* 'x86-alternatives-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/TSC: Use RDTSCP
  x86/alternatives: Add an ALTERNATIVE_3() macro
  x86/alternatives: Print containing function
  x86/alternatives: Add macro comments
2019-03-06 08:45:46 -08:00
Linus Torvalds
203b6609e0 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Lots of tooling updates - too many to list, here's a few highlights:

   - Various subcommand updates to 'perf trace', 'perf report', 'perf
     record', 'perf annotate', 'perf script', 'perf test', etc.

   - CPU and NUMA topology and affinity handling improvements,

   - HW tracing and HW support updates:
      - Intel PT updates
      - ARM CoreSight updates
      - vendor HW event updates

   - BPF updates

   - Tons of infrastructure updates, both on the build system and the
     library support side

   - Documentation updates.

   - ... and lots of other changes, see the changelog for details.

  Kernel side updates:

   - Tighten up kprobes blacklist handling, reduce the number of places
     where developers can install a kprobe and hang/crash the system.

   - Fix/enhance vma address filter handling.

   - Various PMU driver updates, small fixes and additions.

   - refcount_t conversions

   - BPF updates

   - error code propagation enhancements

   - misc other changes"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (238 commits)
  perf script python: Add Python3 support to syscall-counts-by-pid.py
  perf script python: Add Python3 support to syscall-counts.py
  perf script python: Add Python3 support to stat-cpi.py
  perf script python: Add Python3 support to stackcollapse.py
  perf script python: Add Python3 support to sctop.py
  perf script python: Add Python3 support to powerpc-hcalls.py
  perf script python: Add Python3 support to net_dropmonitor.py
  perf script python: Add Python3 support to mem-phys-addr.py
  perf script python: Add Python3 support to failed-syscalls-by-pid.py
  perf script python: Add Python3 support to netdev-times.py
  perf tools: Add perf_exe() helper to find perf binary
  perf script: Handle missing fields with -F +..
  perf data: Add perf_data__open_dir_data function
  perf data: Add perf_data__(create_dir|close_dir) functions
  perf data: Fail check_backup in case of error
  perf data: Make check_backup work over directories
  perf tools: Add rm_rf_perf_data function
  perf tools: Add pattern name checking to rm_rf
  perf tools: Add depth checking to rm_rf
  perf data: Add global path holder
  ...
2019-03-06 07:59:36 -08:00
Linus Torvalds
c8f5ed6ef9 Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main EFI changes in this cycle were:

   - Use 32-bit alignment for efi_guid_t

   - Allow the SetVirtualAddressMap() call to be omitted

   - Implement earlycon=efifb based on existing earlyprintk code

   - Various minor fixes and code cleanups from Sai, Ard and me"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: Fix build error due to enum collision between efi.h and ima.h
  efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation
  x86: Make ARCH_USE_MEMREMAP_PROT a generic Kconfig symbol
  efi/arm/arm64: Allow SetVirtualAddressMap() to be omitted
  efi: Replace GPL license boilerplate with SPDX headers
  efi/fdt: Apply more cleanups
  efi: Use 32-bit alignment for efi_guid_t
  efi/memattr: Don't bail on zero VA if it equals the region's PA
  x86/efi: Mark can_free_region() as an __init function
2019-03-06 07:13:56 -08:00
Alexey Dobriyan
b9726c26dc numa: make "nr_node_ids" unsigned int
Number of NUMA nodes can't be negative.

This saves a few bytes on x86_64:

	add/remove: 0/0 grow/shrink: 4/21 up/down: 27/-265 (-238)
	Function                                     old     new   delta
	hv_synic_alloc.cold                           88     110     +22
	prealloc_shrinker                            260     262      +2
	bootstrap                                    249     251      +2
	sched_init_numa                             1566    1567      +1
	show_slab_objects                            778     777      -1
	s_show                                      1201    1200      -1
	kmem_cache_init                              346     345      -1
	__alloc_workqueue_key                       1146    1145      -1
	mem_cgroup_css_alloc                        1614    1612      -2
	__do_sys_swapon                             4702    4699      -3
	__list_lru_init                              655     651      -4
	nic_probe                                   2379    2374      -5
	store_user_store                             118     111      -7
	red_zone_store                               106      99      -7
	poison_store                                 106      99      -7
	wq_numa_init                                 348     338     -10
	__kmem_cache_empty                            75      65     -10
	task_numa_free                               186     173     -13
	merge_across_nodes_store                     351     336     -15
	irq_create_affinity_masks                   1261    1246     -15
	do_numa_crng_init                            343     321     -22
	task_numa_fault                             4760    4737     -23
	swapfile_init                                179     156     -23
	hv_synic_alloc                               536     492     -44
	apply_wqattrs_prepare                        746     695     -51

Link: http://lkml.kernel.org/r/20190201223029.GA15820@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:19 -08:00
Anshuman Khandual
98fa15f34c mm: replace all open encodings for NUMA_NO_NODE
Patch series "Replace all open encodings for NUMA_NO_NODE", v3.

All these places for replacement were found by running the following
grep patterns on the entire kernel code.  Please let me know if this
might have missed some instances.  This might also have replaced some
false positives.  I will appreciate suggestions, inputs and review.

1. git grep "nid == -1"
2. git grep "node == -1"
3. git grep "nid = -1"
4. git grep "node = -1"

This patch (of 2):

At present there are multiple places where invalid node number is
encoded as -1.  Even though implicitly understood it is always better to
have macros in there.  Replace these open encodings for an invalid node
number with the global macro NUMA_NO_NODE.  This helps remove NUMA
related assumptions like 'invalid node' from various places redirecting
them to a common definition.

Link: http://lkml.kernel.org/r/1545127933-10711-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>	[ixgbe]
Acked-by: Jens Axboe <axboe@kernel.dk>			[mtip32xx]
Acked-by: Vinod Koul <vkoul@kernel.org>			[dmaengine.c]
Acked-by: Michael Ellerman <mpe@ellerman.id.au>		[powerpc]
Acked-by: Doug Ledford <dledford@redhat.com>		[drivers/infiniband]
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:14 -08:00
Linus Torvalds
edaed168e1 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/pti update from Thomas Gleixner:
 "Just a single change from the anti-performance departement:

   - Add a new PR_SPEC_DISABLE_NOEXEC option which allows to apply the
     speculation protections on a process without inheriting the state
     on exec.

     This remedies a situation where a Java-launcher has speculation
     protections enabled because that's the default for JVMs which
     causes the launched regular harmless processes to inherit the
     protection state which results in unintended performance
     degradation"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/speculation: Add PR_SPEC_DISABLE_NOEXEC
2019-03-05 12:50:34 -08:00
Steven Rostedt (VMware)
745cfeaac0 x86/ftrace: Fix warning and considate ftrace_jmp_replace() and ftrace_call_replace()
Arnd reported the following compiler warning:

arch/x86/kernel/ftrace.c:669:23: error: 'ftrace_jmp_replace' defined but not used [-Werror=unused-function]

The ftrace_jmp_replace() function now only has a single user and should be
simply moved by that user. But looking at the code, it shows that
ftrace_jmp_replace() is similar to ftrace_call_replace() except that instead
of using the opcode of 0xe8 it uses 0xe9. It makes more sense to consolidate
that function into one implementation that both ftrace_jmp_replace() and
ftrace_call_replace() use by passing in the op code separate.

The structure in ftrace_code_union is also modified to replace the "e8"
field with the more appropriate name "op".

Cc: stable@vger.kernel.org
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/20190304200748.1418790-1-arnd@arndb.de
Fixes: d2a68c4effd8 ("x86/ftrace: Do not call function graph from dynamic trampolines")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-05 08:45:08 -05:00
Lan Tianyu
84fdfafab8 x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available
Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic,
set x2apic destination mode to physcial mode when x2apic is available
and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs have
8-bit APIC id.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-02-28 11:12:16 +01:00
David Howells
23bf1b6be9 kernfs, sysfs, cgroup, intel_rdt: Support fs_context
Make kernfs support superblock creation/mount/remount with fs_context.

This requires that sysfs, cgroup and intel_rdt, which are built on kernfs,
be made to support fs_context also.

Notes:

 (1) A kernfs_fs_context struct is created to wrap fs_context and the
     kernfs mount parameters are moved in here (or are in fs_context).

 (2) kernfs_mount{,_ns}() are made into kernfs_get_tree().  The extra
     namespace tag parameter is passed in the context if desired

 (3) kernfs_free_fs_context() is provided as a destructor for the
     kernfs_fs_context struct, but for the moment it does nothing except
     get called in the right places.

 (4) sysfs doesn't wrap kernfs_fs_context since it has no parameters to
     pass, but possibly this should be done anyway in case someone wants to
     add a parameter in future.

 (5) A cgroup_fs_context struct is created to wrap kernfs_fs_context and
     the cgroup v1 and v2 mount parameters are all moved there.

 (6) cgroup1 parameter parsing error messages are now handled by invalf(),
     which allows userspace to collect them directly.

 (7) cgroup1 parameter cleanup is now done in the context destructor rather
     than in the mount/get_tree and remount functions.

Weirdies:

 (*) cgroup_do_get_tree() calls cset_cgroup_from_root() with locks held,
     but then uses the resulting pointer after dropping the locks.  I'm
     told this is okay and needs commenting.

 (*) The cgroup refcount web.  This really needs documenting.

 (*) cgroup2 only has one root?

Add a suggestion from Thomas Gleixner in which the RDT enablement code is
placed into its own function.

[folded a leak fix from Andrey Vagin]

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Tejun Heo <tj@kernel.org>
cc: Li Zefan <lizefan@huawei.com>
cc: Johannes Weiner <hannes@cmpxchg.org>
cc: cgroups@vger.kernel.org
cc: fenghua.yu@intel.com
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-28 03:29:34 -05:00
Ingo Molnar
9ed8f1a6e7 Merge branch 'linus' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-28 08:27:17 +01:00
Tony Luck
41f035a86b x86/mce: Improve error message when kernel cannot recover, p2
In

  c7d606f560e4 ("x86/mce: Improve error message when kernel cannot recover")

a case was added for a machine check caused by a DATA access to poison
memory from the kernel. A case should have been added also for an
uncorrectable error during an instruction fetch in the kernel.

Add that extra case so the error message now reads:

  mce: [Hardware Error]: Machine check: Instruction fetch error in kernel

Fixes: c7d606f560e4 ("x86/mce: Improve error message when kernel cannot recover")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190225205940.15226-1-tony.luck@intel.com
2019-02-25 23:21:35 +01:00
Marcelo Tosatti
7539b174ae x86: kvmguest: use TSC clocksource if invariant TSC is exposed
The invariant TSC bit has the following meaning:

"The time stamp counter in newer processors may support an enhancement,
referred to as invariant TSC. Processor's support for invariant TSC
is indicated by CPUID.80000007H:EDX[8]. The invariant TSC will run
at a constant rate in all ACPI P-, C-. and T-states. This is the
architectural behavior moving forward. On processors with invariant TSC
support, the OS may use the TSC for wall clock timer services (instead
of ACPI or HPET timers). TSC reads are much more efficient and do not
incur the overhead associated with a ring transition or access to a
platform resource."

IOW, TSC does not change frequency. In such case, and with
TSC scaling hardware available to handle migration, it is possible
to use the TSC clocksource directly, whose system calls are
faster.

Reduce the rating of kvmclock clocksource to allow TSC clocksource
to be the default if invariant TSC is exposed.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

v2: Use feature bits and tsc_unstable() check (Sean Christopherson)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-20 22:48:52 +01:00
Pavel Tatashin
b5179ec418 x86/kvmclock: set offset for kvm unstable clock
VMs may show incorrect uptime and dmesg printk offsets on hypervisors with
unstable clock. The problem is produced when VM is rebooted without exiting
from qemu.

The fix is to calculate clock offset not only for stable clock but for
unstable clock as well, and use kvm_sched_clock_read() which substracts
the offset for both clocks.

This is safe, because pvclock_clocksource_read() does the right thing and
makes sure that clock always goes forward, so once offset is calculated
with unstable clock, we won't get new reads that are smaller than offset,
and thus won't get negative results.

Thank you Jon DeVree for helping to reproduce this issue.

Fixes: 857baa87b642 ("sched/clock: Enable sched clock early")
Cc: stable@vger.kernel.org
Reported-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-20 22:48:19 +01:00
Shaokun Zhang
f91fecc09e x86/smpboot: Remove unused phys_id variable
The 'phys_id' local variable became unused after commit

  ce4b1b16502b ("x86/smpboot: Initialize secondary CPU only if master CPU will wait for it").

Remove it.

Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Link: https://lkml.kernel.org/r/1550495101-41755-1-git-send-email-zhangshaokun@hisilicon.com
2019-02-18 17:09:24 +01:00
Juergen Gross
357b4da50a x86: respect memory size limiting via mem= parameter
When limiting memory size via kernel parameter "mem=" this should be
respected even in case of memory made accessible via a PCI card.

Today this kind of memory won't be made usable in initial memory
setup as the memory won't be visible in E820 map, but it might be
added when adding PCI devices due to corresponding ACPI table entries.

Not respecting "mem=" can be corrected by adding a global max_mem_size
variable set by parse_memopt() which will result in rejecting adding
memory areas resulting in a memory size above the allowed limit.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2019-02-18 06:50:34 +01:00
Masami Hiramatsu
0eae81dc9f x86/kprobes: Prohibit probing on IRQ handlers directly
Prohibit probing on IRQ handlers in irqentry_text because
if it interrupts user mode, at that point we haven't changed
to kernel space yet and which eventually leads a double fault.
E.g.

 # echo p apic_timer_interrupt > kprobe_events
 # echo 1 > events/kprobes/enable
 PANIC: double fault, error_code: 0x0
 CPU: 1 PID: 814 Comm: less Not tainted 4.20.0-rc3+ #30
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
 RIP: 0010:error_entry+0x12/0xf0
 [snip]
 Call Trace:
  <ENTRY_TRAMPOLINE>
  ? native_iret+0x7/0x7
  ? async_page_fault+0x8/0x30
  ? trace_hardirqs_on_thunk+0x1c/0x1c
  ? error_entry+0x7c/0xf0
  ? async_page_fault+0x8/0x30
  ? native_iret+0x7/0x7
  ? int3+0xa/0x20
  ? trace_hardirqs_on_thunk+0x1c/0x1c
  ? error_entry+0x7c/0xf0
  ? int3+0xa/0x20
  ? apic_timer_interrupt+0x1/0x20
  </ENTRY_TRAMPOLINE>
 Kernel panic - not syncing: Machine halted.
 Kernel Offset: disabled
 ---[ end Kernel panic - not syncing: Machine halted. ]---

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998796400.31052.8406236614820687840.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-13 08:16:39 +01:00
Masami Hiramatsu
c13324a505 x86/kprobes: Prohibit probing on functions before kprobe_int3_handler()
Prohibit probing on the functions called before kprobe_int3_handler()
in do_int3(). More specifically, ftrace_int3_handler(),
poke_int3_handler(), and ist_enter(). And since rcu_nmi_enter() is
called by ist_enter(), it also should be marked as NOKPROBE_SYMBOL.

Since those are handled before kprobe_int3_handler(), probing those
functions can cause a breakpoint recursion and crash the kernel.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998793571.31052.11301258949601150994.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-13 08:16:39 +01:00
Masami Hiramatsu
877b145f0f x86/kprobes: Move trampoline code into RODATA
Move optprobe trampoline code into RODATA since it is
not executed, but copied and modified to be used on
a trampoline buffer.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998790744.31052.3016106262944915510.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-13 08:16:39 +01:00
Masami Hiramatsu
0192e6535e x86/kprobes: Prohibit probing on optprobe template code
Prohibit probing on optprobe template code, since it is not
a code but a template instruction sequence. If we modify
this template, copied template must be broken.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: 9326638cbee2 ("kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotation")
Link: http://lkml.kernel.org/r/154998787911.31052.15274376330136234452.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-13 08:16:39 +01:00
Ingo Molnar
dc14b5fe7d Linux 5.0-rc6
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Merge tag 'v5.0-rc6' into x86/fpu, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-11 12:52:51 +01:00
Ingo Molnar
f26d9db21b Merge branch 'x86/cpu' into perf/core, to pick up dependent commit
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-11 08:00:26 +01:00
Kan Liang
0f42b790c9 x86/cpufeature: Add facility to check for min microcode revisions
For bug workarounds or checks, it is useful to check for specific
microcode revisions.

Add a new generic function to match the CPU with stepping.
Add the other function to check the min microcode revisions for
the matched CPU.

A new table format is introduced to facilitate the quirk to
fill the related information.

This does not change the existing x86_cpu_id because it's an ABI
shared with modules, and also has quite different requirements,
as in no wildcards, but everything has to be matched exactly.

Originally-by: Andi Kleen <ak@linux.intel.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: eranian@google.com
Link: https://lkml.kernel.org/r/1549319013-4522-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-11 07:59:23 +01:00
Linus Torvalds
aadaa80611 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "A handful of fixes:

   - Fix an MCE corner case bug/crash found via MCE injection testing

   - Fix 5-level paging boot crash

   - Fix MCE recovery cache invalidation bug

   - Fix regression on Xen guests caused by a recent PMD level mremap
     speedup optimization"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Make set_pmd_at() paravirt aware
  x86/mm/cpa: Fix set_mce_nospec()
  x86/boot/compressed/64: Do not corrupt EDX on EFER.LME=1 setting
  x86/MCE: Initialize mce.bank in the case of a fatal error in mce_no_way_out()
2019-02-10 09:57:42 -08:00
Sergey Senozhatsky
653a561bb2 x86/fpu: Move init_xstate_size() to __init section
WARNING: vmlinux.o(.text.unlikely+0x1c05): Section mismatch in
         reference from the function init_xstate_size() to the
         function .init.text:get_xsave_size()

WARNING: vmlinux.o(.text.unlikely+0x1c19): Section mismatch in
         reference from the function init_xstate_size() to the
         function .init.text:get_xsaves_size()

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Link: https://lkml.kernel.org/r/20190108130225.5066-2-sergey.senozhatsky@gmail.com
2019-02-08 14:32:34 +01:00
Bo Yu
c81cd5c08d x86/mtrr: Remove unused variable
Compiling the kernel with W=1 results in the following warning:

arch/x86/kernel/cpu/mtrr/cleanup.c:299:16: warning: variable ‘second_basek’ set but not used [-Wunused-but-set-variable]
  unsigned long second_basek, second_sizek;

Remove the unused variable.

[ tglx: Massaged changelog ]

Signed-off-by: Bo Yu <tsu.yubo@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: puwen@hygon.cn
Link: https://lkml.kernel.org/r/20190208125343.11451-1-tsu.yubo@gmail.com
2019-02-08 14:32:33 +01:00
Kairui Song
ccec81e425 x86/kexec: Fill in acpi_rsdp_addr from the first kernel
When efi=noruntime or efi=oldmap is used on the kernel command line, EFI
services won't be available in the second kernel, therefore the second
kernel will not be able to get the ACPI RSDP address from firmware by
calling EFI services and so it won't boot.

Commit

  e6e094e053af ("x86/acpi, x86/boot: Take RSDP address from boot params if available")

added an acpi_rsdp_addr field to boot_params which stores the RSDP
address for other kernel users.

Recently, after

  3a63f70bf4c3 ("x86/boot: Early parse RSDP and save it in boot_params")

the acpi_rsdp_addr will always be filled with a valid RSDP address.

So fill in that value into the second kernel's boot_params thus ensuring
that the second kernel receives the RSDP value from the first kernel.

 [ bp: massage commit message. ]

Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: kexec@lists.infradead.org
Cc: Philipp Rudo <prudo@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: Yannik Sembritzki <yannik@sembritzki.me>
Link: https://lkml.kernel.org/r/20190204173852.4863-1-kasong@redhat.com
2019-02-06 15:29:03 +01:00
Reinette Chatre
8ad382dd11 x86/resctrl: Remove duplicate MSR_MISC_FEATURE_CONTROL definition
The definition of MSR_MISC_FEATURE_CONTROL was first introduced in

  98af74599ea0 ("x86 msr_index.h: Define MSR_MISC_FEATURE_CONTROL")

and present in Linux since v4.11.

The Cache Pseudo-Locking code added this duplicate definition in more
recent

  f2a177292bd0 ("x86/intel_rdt: Discover supported platforms via prefetch disable bits"),

available since v4.19.

Remove the duplicate definition from the resctrl subsystem and let that
code obtain the needed definition from the core architecture msr-index.h
instead.

Fixes: f2a177292bd0 ("x86/intel_rdt: Discover supported platforms via prefetch disable bits")
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: gavin.hindman@intel.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: jithu.joseph@intel.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/ff6b95d9b6ef6f4ac96267f130719ba1af09614b.1549312475.git.reinette.chatre@intel.com
2019-02-05 07:21:56 +01:00
Kairui Song
278311e417 kexec, KEYS: Make use of platform keyring for signature verify
This patch allows the kexec_file_load syscall to verify the PE signed
kernel image signature based on the preboot keys stored in the .platform
keyring, as fall back, if the signature verification failed due to not
finding the public key in the secondary or builtin keyrings.

This commit adds a VERIFY_USE_PLATFORM_KEYRING similar to previous
VERIFY_USE_SECONDARY_KEYRING indicating that verify_pkcs7_signature
should verify the signature using platform keyring.  Also, decrease
the error message log level when verification failed with -ENOKEY,
so that if called tried multiple time with different keyring it
won't generate extra noises.

Signed-off-by: Kairui Song <kasong@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com> (for kexec_file_load part)
[zohar@linux.ibm.com: tweaked the first paragraph of the patch description,
 and fixed checkpatch warning.]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-02-04 17:34:07 -05:00
Ard Biesheuvel
69c1f396f2 efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation
Move the x86 EFI earlyprintk implementation to a shared location under
drivers/firmware and tweak it slightly so we can expose it as an earlycon
implementation (which is generic) rather than earlyprintk (which is only
implemented for a few architectures)

This also involves switching to write-combine mappings by default (which
is required on ARM since device mappings lack memory semantics, and so
memcpy/memset may not be used on them), and adding support for shared
memory framebuffers on cache coherent non-x86 systems (which do not
tolerate mismatched attributes).

Note that 32-bit ARM does not populate its struct screen_info early
enough for earlycon=efifb to work, so it is disabled there.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Alexander Graf <agraf@suse.de>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190202094119.13230-10-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:27:30 +01:00
Linus Torvalds
24b888d8d5 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A few updates for x86:

   - Fix an unintended sign extension issue in the fault handling code

   - Rename the new resource control config switch so it's less
     confusing

   - Avoid setting up EFI info in kexec when the EFI runtime is
     disabled.

   - Fix the microcode version check in the AMD microcode loader so it
     only loads higher version numbers and never downgrades

   - Set EFER.LME in the 32bit trampoline before returning to long mode
     to handle older AMD/KVM behaviour properly.

   - Add Darren and Andy as x86/platform reviewers"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Avoid confusion over the new X86_RESCTRL config
  x86/kexec: Don't setup EFI info if EFI runtime is not enabled
  x86/microcode/amd: Don't falsely trick the late loading mechanism
  MAINTAINERS: Add Andy and Darren as arch/x86/platform/ reviewers
  x86/fault: Fix sign-extend unintended sign extension
  x86/boot/compressed/64: Set EFER.LME=1 in 32-bit trampoline before returning to long mode
  x86/cpu: Add Atom Tremont (Jacobsville)
2019-02-03 09:08:12 -08:00
Tony Luck
d28af26faa x86/MCE: Initialize mce.bank in the case of a fatal error in mce_no_way_out()
Internal injection testing crashed with a console log that said:

  mce: [Hardware Error]: CPU 7: Machine Check Exception: f Bank 0: bd80000000100134

This caused a lot of head scratching because the MCACOD (bits 15:0) of
that status is a signature from an L1 data cache error. But Linux says
that it found it in "Bank 0", which on this model CPU only reports L1
instruction cache errors.

The answer was that Linux doesn't initialize "m->bank" in the case that
it finds a fatal error in the mce_no_way_out() pre-scan of banks. If
this was a local machine check, then this partially initialized struct
mce is being passed to mce_panic().

Fix is simple: just initialize m->bank in the case of a fatal error.

Fixes: 40c36e2741d7 ("x86/mce: Fix incorrect "Machine check from unknown source" message")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: x86-ml <x86@kernel.org>
Cc: stable@vger.kernel.org # v4.18 Note pre-v5.0 arch/x86/kernel/cpu/mce/core.c was called arch/x86/kernel/cpu/mcheck/mce.c
Link: https://lkml.kernel.org/r/20190201003341.10638-1-tony.luck@intel.com
2019-02-03 13:24:24 +01:00
Yazen Ghannam
8a5dd2cd2f x86/MCE/AMD, EDAC/mce_amd: Add new error descriptions for some SMCA bank types
Some SMCA bank types on future systems will report new error types even
though the bank type is not treated as a new version. These new error
types will reported by bits that are reserved in past systems.

Add the new error descriptions to the lists in edac_mce_amd.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Shirish S <Shirish.S@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190201225534.8177-4-Yazen.Ghannam@amd.com
2019-02-03 13:05:16 +01:00
Yazen Ghannam
3ad7e748c1 x86/MCE/AMD, EDAC/mce_amd: Add new McaTypes for CS, PSP, and SMU units
The existing CS, PSP, and SMU SMCA bank types will see new versions (as
indicated by their McaTypes) in future SMCA systems.

Add the new (HWID, MCATYPE) tuples for these new versions. Reuse the
same names as the older versions, since they are logically the same to
the user. SMCA systems won't mix and match IP blocks with different
McaType versions in the same system, so there isn't a need to
distinguish them. The MCA_IPID register is saved when logging an MCA
error, and that can be used to triage the error.

Also, add the new error descriptions to edac_mce_amd. Some error types
(positions in the list) are overloaded compared to the previous
McaTypes. Therefore, just create new lists of the error descriptions to
keep things simple even if some of the error descriptions are the same
between versions.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: Shirish S <Shirish.S@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190201225534.8177-3-Yazen.Ghannam@amd.com
2019-02-03 13:01:57 +01:00
Yazen Ghannam
cbfa447edd x86/MCE/AMD, EDAC/mce_amd: Add new MP5, NBIO, and PCIE SMCA bank types
Add the (HWID, MCATYPE) tuples and names for the new MP5, NBIO, and
PCIE SMCA bank types.

Also, add their respective error descriptions to the MCE decoding module
edac_mce_amd.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: Shirish S <Shirish.S@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190201225534.8177-2-Yazen.Ghannam@amd.com
2019-02-03 13:01:44 +01:00
Johannes Weiner
e6d429313e x86/resctrl: Avoid confusion over the new X86_RESCTRL config
"Resource Control" is a very broad term for this CPU feature, and a term
that is also associated with containers, cgroups etc. This can easily
cause confusion.

Make the user prompt more specific. Match the config symbol name.

 [ bp: In the future, the corresponding ARM arch-specific code will be
   under ARM_CPU_RESCTRL and the arch-agnostic bits will be carved out
   under the CPU_RESCTRL umbrella symbol. ]

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Babu Moger <Babu.Moger@amd.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morse <james.morse@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: linux-doc@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190130195621.GA30653@cmpxchg.org
2019-02-02 10:34:52 +01:00
Kairui Song
2aa958c99c x86/kexec: Don't setup EFI info if EFI runtime is not enabled
Kexec-ing a kernel with "efi=noruntime" on the first kernel's command
line causes the following null pointer dereference:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
  #PF error: [normal kernel read fault]
  Call Trace:
   efi_runtime_map_copy+0x28/0x30
   bzImage64_load+0x688/0x872
   arch_kexec_kernel_image_load+0x6d/0x70
   kimage_file_alloc_init+0x13e/0x220
   __x64_sys_kexec_file_load+0x144/0x290
   do_syscall_64+0x55/0x1a0
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

Just skip the EFI info setup if EFI runtime services are not enabled.

 [ bp: Massage commit message. ]

Suggested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: bhe@redhat.com
Cc: David Howells <dhowells@redhat.com>
Cc: erik.schmauss@intel.com
Cc: fanc.fnst@cn.fujitsu.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: kexec@lists.infradead.org
Cc: lenb@kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: Philipp Rudo <prudo@linux.vnet.ibm.com>
Cc: rafael.j.wysocki@intel.com
Cc: robert.moore@intel.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: Yannik Sembritzki <yannik@sembritzki.me>
Link: https://lkml.kernel.org/r/20190118111310.29589-2-kasong@redhat.com
2019-02-01 18:18:54 +01:00
Thomas Lendacky
912139cfbf x86/microcode/amd: Don't falsely trick the late loading mechanism
The load_microcode_amd() function searches for microcode patches and
attempts to apply a microcode patch if it is of different level than the
currently installed level.

While the processor won't actually load a level that is less than
what is already installed, the logic wrongly returns UCODE_NEW thus
signaling to its caller reload_store() that a late loading should be
attempted.

If the file-system contains an older microcode revision than what is
currently running, such a late microcode reload can result in these
misleading messages:

  x86/CPU: CPU features have changed after loading microcode, but might not take effect.
  x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update.

These messages were issued on a system where SME/SEV are not
enabled by the BIOS (MSR C001_0010[23] = 0b) because during boot,
early_detect_mem_encrypt() is called and cleared the SME and SEV
features in this case.

However, after the wrong late load attempt, get_cpu_cap() is called and
reloads the SME and SEV feature bits, resulting in the messages.

Update the microcode level check to not attempt microcode loading if the
current level is greater than(!) and not only equal to the current patch
level.

 [ bp: massage commit message. ]

Fixes: 2613f36ed965 ("x86/microcode: Attempt late loading only when new microcode is present")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/154894518427.9406.8246222496874202773.stgit@tlendack-t1.amdoffice.net
2019-01-31 16:54:32 +01:00
Josh Poimboeuf
b284909aba cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVM
With the following commit:

  73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS")

... the hotplug code attempted to detect when SMT was disabled by BIOS,
in which case it reported SMT as permanently disabled.  However, that
code broke a virt hotplug scenario, where the guest is booted with only
primary CPU threads, and a sibling is brought online later.

The problem is that there doesn't seem to be a way to reliably
distinguish between the HW "SMT disabled by BIOS" case and the virt
"sibling not yet brought online" case.  So the above-mentioned commit
was a bit misguided, as it permanently disabled SMT for both cases,
preventing future virt sibling hotplugs.

Going back and reviewing the original problems which were attempted to
be solved by that commit, when SMT was disabled in BIOS:

  1) /sys/devices/system/cpu/smt/control showed "on" instead of
     "notsupported"; and

  2) vmx_vm_init() was incorrectly showing the L1TF_MSG_SMT warning.

I'd propose that we instead consider #1 above to not actually be a
problem.  Because, at least in the virt case, it's possible that SMT
wasn't disabled by BIOS and a sibling thread could be brought online
later.  So it makes sense to just always default the smt control to "on"
to allow for that possibility (assuming cpuid indicates that the CPU
supports SMT).

The real problem is #2, which has a simple fix: change vmx_vm_init() to
query the actual current SMT state -- i.e., whether any siblings are
currently online -- instead of looking at the SMT "control" sysfs value.

So fix it by:

  a) reverting the original "fix" and its followup fix:

     73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS")
     bc2d8d262cba ("cpu/hotplug: Fix SMT supported evaluation")

     and

  b) changing vmx_vm_init() to query the actual current SMT state --
     instead of the sysfs control value -- to determine whether the L1TF
     warning is needed.  This also requires the 'sched_smt_present'
     variable to exported, instead of 'cpu_smt_control'.

Fixes: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS")
Reported-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Joe Mario <jmario@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/e3a85d585da28cc333ecbc1e78ee9216e6da9396.1548794349.git.jpoimboe@redhat.com
2019-01-30 19:27:00 +01:00
Jiri Slaby
5a064d398f x86/asm/suspend: Drop ENTRY from local data
ENTRY is intended for functions and shall be paired with ENDPROC. ENTRY
also aligns symbols which creates unnecessary holes between data.

So drop ENTRY from saved_eip in wakeup_32 and many saved_* in wakeup_64,
as these symbols are local only.

One could've used SYM_DATA_LOCAL for these symbols, but it was
discouraged earlier:

  https://lkml.kernel.org/r/20170427124310.GC23352@amd

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190130124711.12463-3-jslaby@suse.cz
2019-01-30 16:07:10 +01:00
Borislav Petkov
fab940755d x86/hw_breakpoints, kprobes: Remove kprobes ifdeffery
Remove the ifdeffery in the breakpoint parsing arch_build_bp_info() by
adding a within_kprobe_blacklist() stub for the !CONFIG_KPROBES case.

It is returning true when kprobes are not enabled to mean that any
address is within the kprobes blacklist on such kernels and thus not
allow kernel breakpoints on non-kprobes kernels.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190127131237.4557-1-bp@alien8.de
2019-01-30 11:52:21 +01:00