Commit Graph

278 Commits

Author SHA1 Message Date
Linus Torvalds
3ef3ace4e2 - Split MTRR and PAT init code to accomodate at least Xen PV and TDX
guests which do not get MTRRs exposed but only PAT. (TDX guests do not
 support the cache disabling dance when setting up MTRRs so they fall
 under the same category.) This is a cleanup work to remove all the ugly
 workarounds for such guests and init things separately (Juergen Gross)
 
 - Add two new Intel CPUs to the list of CPUs with "normal" Energy
 Performance Bias, leading to power savings
 
 - Do not do bus master arbitration in C3 (ARB_DISABLE) on modern Centaur
 CPUs
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Merge tag 'x86_cpu_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpu updates from Borislav Petkov:

 - Split MTRR and PAT init code to accomodate at least Xen PV and TDX
   guests which do not get MTRRs exposed but only PAT. (TDX guests do
   not support the cache disabling dance when setting up MTRRs so they
   fall under the same category)

   This is a cleanup work to remove all the ugly workarounds for such
   guests and init things separately (Juergen Gross)

 - Add two new Intel CPUs to the list of CPUs with "normal" Energy
   Performance Bias, leading to power savings

 - Do not do bus master arbitration in C3 (ARB_DISABLE) on modern
   Centaur CPUs

* tag 'x86_cpu_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  x86/mtrr: Make message for disabled MTRRs more descriptive
  x86/pat: Handle TDX guest PAT initialization
  x86/cpuid: Carve out all CPUID functionality
  x86/cpu: Switch to cpu_feature_enabled() for X86_FEATURE_XENPV
  x86/cpu: Remove X86_FEATURE_XENPV usage in setup_cpu_entry_area()
  x86/cpu: Drop 32-bit Xen PV guest code in update_task_stack()
  x86/cpu: Remove unneeded 64-bit dependency in arch_enter_from_user_mode()
  x86/cpufeatures: Add X86_FEATURE_XENPV to disabled-features.h
  x86/acpi/cstate: Optimize ARB_DISABLE on Centaur CPUs
  x86/mtrr: Simplify mtrr_ops initialization
  x86/cacheinfo: Switch cache_ap_init() to hotplug callback
  x86: Decouple PAT and MTRR handling
  x86/mtrr: Add a stop_machine() handler calling only cache_cpu_init()
  x86/mtrr: Let cache_aps_delayed_init replace mtrr_aps_delayed_init
  x86/mtrr: Get rid of __mtrr_enabled bool
  x86/mtrr: Simplify mtrr_bp_init()
  x86/mtrr: Remove set_all callback from struct mtrr_ops
  x86/mtrr: Disentangle MTRR init from PAT init
  x86/mtrr: Move cache control code to cacheinfo.c
  x86/mtrr: Split MTRR-specific handling from cache dis/enabling
  ...
2022-12-13 14:56:56 -08:00
Juergen Gross
6007878a78 x86/cpu: Switch to cpu_feature_enabled() for X86_FEATURE_XENPV
Convert the remaining cases of static_cpu_has(X86_FEATURE_XENPV) and
boot_cpu_has(X86_FEATURE_XENPV) to use cpu_feature_enabled(), allowing
more efficient code in case the kernel is configured without
CONFIG_XEN_PV.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20221104072701.20283-6-jgross@suse.com
2022-11-22 16:18:19 +01:00
Borislav Petkov
2632daebaf x86/cpu: Restore AMD's DE_CFG MSR after resume
DE_CFG contains the LFENCE serializing bit, restore it on resume too.
This is relevant to older families due to the way how they do S3.

Unify and correct naming while at it.

Fixes: e4d0e84e49 ("x86/cpu/AMD: Make LFENCE a serializing instruction")
Reported-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Reported-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-11-15 10:15:58 -08:00
Jason A. Donenfeld
a251c17aa5 treewide: use get_random_u32() when possible
The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake
Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Acked-by: Helge Deller <deller@gmx.de> # for parisc
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-11 17:42:58 -06:00
Jason A. Donenfeld
049f9ae93d x86/rdrand: Remove "nordrand" flag in favor of "random.trust_cpu"
The decision of whether or not to trust RDRAND is controlled by the
"random.trust_cpu" boot time parameter or the CONFIG_RANDOM_TRUST_CPU
compile time default. The "nordrand" flag was added during the early
days of RDRAND, when there were worries that merely using its values
could compromise the RNG. However, these days, RDRAND values are not
used directly but always go through the RNG's hash function, making
"nordrand" no longer useful.

Rather, the correct switch is "random.trust_cpu", which not only handles
the relevant trust issue directly, but also is general to multiple CPU
types, not just x86.

However, x86 RDRAND does have a history of being occasionally
problematic. Prior, when the kernel would notice something strange, it'd
warn in dmesg and suggest enabling "nordrand". We can improve on that by
making the test a little bit better and then taking the step of
automatically disabling RDRAND if we detect it's problematic.

Also disable RDSEED if the RDRAND test fails.

Cc: x86@kernel.org
Cc: Theodore Ts'o <tytso@mit.edu>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Suggested-by: Borislav Petkov <bp@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-07-18 15:04:04 +02:00
Peter Zijlstra
f43b9876e8 x86/retbleed: Add fine grained Kconfig knobs
Do fine-grained Kconfig for all the various retbleed parts.

NOTE: if your compiler doesn't support return thunks this will
silently 'upgrade' your mitigation to IBPB, you might not like this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-29 17:43:41 +02:00
Andrew Cooper
26aae8ccbc x86/cpu/amd: Enumerate BTC_NO
BTC_NO indicates that hardware is not susceptible to Branch Type Confusion.

Zen3 CPUs don't suffer BTC.

Hypervisors are expected to synthesise BTC_NO when it is appropriate
given the migration pool, to prevent kernels using heuristics.

  [ bp: Massage. ]

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27 10:34:01 +02:00
Peter Zijlstra
d7caac991f x86/cpu/amd: Add Spectral Chicken
Zen2 uarchs have an undocumented, unnamed, MSR that contains a chicken
bit for some speculation behaviour. It needs setting.

Note: very belatedly AMD released naming; it's now officially called
      MSR_AMD64_DE_CFG2 and MSR_AMD64_DE_CFG2_SUPPRESS_NOBR_PRED_BIT
      but shall remain the SPECTRAL CHICKEN.

Suggested-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27 10:34:00 +02:00
Mario Limonciello
08f253ec37 x86/cpu: Clear SME feature flag when not in use
Currently, the SME CPU feature flag is reflective of whether the CPU
supports the feature but not whether it has been activated by the
kernel.

Change this around to clear the SME feature flag if the kernel is not
using it so userspace can determine if it is available and in use
from /proc/cpuinfo.

As the feature flag is cleared on systems where SME isn't active, use
CPUID 0x8000001f to confirm SME availability before calling
native_wbinvd().

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20220216034446.2430634-1-mario.limonciello@amd.com
2022-02-16 19:45:53 +01:00
Tony Luck
0dcab41d34 x86/cpu: Merge Intel and AMD ppin_init() functions
The code to decide whether a system supports the PPIN (Protected
Processor Inventory Number) MSR was cloned from the Intel
implementation. Apart from the X86_FEATURE bit and the MSR numbers it is
identical.

Merge the two functions into common x86 code, but use x86_match_cpu()
instead of the switch (c->x86_model) that was used by the old Intel
code.

No functional change.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220131230111.2004669-2-tony.luck@intel.com
2022-02-01 12:56:23 +01:00
Jane Malalane
415de44076 x86/cpu: Fix migration safety with X86_BUG_NULL_SEL
Currently, Linux probes for X86_BUG_NULL_SEL unconditionally which
makes it unsafe to migrate in a virtualised environment as the
properties across the migration pool might differ.

To be specific, the case which goes wrong is:

1. Zen1 (or earlier) and Zen2 (or later) in a migration pool
2. Linux boots on Zen2, probes and finds the absence of X86_BUG_NULL_SEL
3. Linux is then migrated to Zen1

Linux is now running on a X86_BUG_NULL_SEL-impacted CPU while believing
that the bug is fixed.

The only way to address the problem is to fully trust the "no longer
affected" CPUID bit when virtualised, because in the above case it would
be clear deliberately to indicate the fact "you might migrate to
somewhere which has this behaviour".

Zen3 adds the NullSelectorClearsBase CPUID bit to indicate that loading
a NULL segment selector zeroes the base and limit fields, as well as
just attributes. Zen2 also has this behaviour but doesn't have the NSCB
bit.

 [ bp: Minor touchups. ]

Signed-off-by: Jane Malalane <jane.malalane@citrix.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20211021104744.24126-1-jane.malalane@citrix.com
2021-10-21 20:49:16 +02:00
Kim Phillips
9164d9493a x86/cpu: Add get_llc_id() helper function
Factor out a helper function rather than export cpu_llc_id, which is
needed in order to be able to build the AMD uncore driver as a module.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210817221048.88063-7-kim.phillips@amd.com
2021-08-26 09:14:36 +02:00
Linus Torvalds
2594b713c1 - New AMD models support
- Allow MONITOR/MWAIT to be used for C1 state entry on Hygon too
 
 - Use the special RAPL CPUID bit to detect the functionality on AMD and
   Hygon instead of doing family matching.
 
 - Add support for new Intel microcode deprecating TSX on some models and
 do not enable kernel workarounds for those CPUs when TSX transactions
 always abort, as a result of that microcode update.
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Merge tag 'x86_cpu_for_v5.14_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpu updates from Borislav Petkov:

 - New AMD models support

 - Allow MONITOR/MWAIT to be used for C1 state entry on Hygon too

 - Use the special RAPL CPUID bit to detect the functionality on AMD and
   Hygon instead of doing family matching.

 - Add support for new Intel microcode deprecating TSX on some models
   and do not enable kernel workarounds for those CPUs when TSX
   transactions always abort, as a result of that microcode update.

* tag 'x86_cpu_for_v5.14_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tsx: Clear CPUID bits when TSX always force aborts
  x86/events/intel: Do not deploy TSX force abort workaround when TSX is deprecated
  x86/msr: Define new bits in TSX_FORCE_ABORT MSR
  perf/x86/rapl: Use CPUID bit on AMD and Hygon parts
  x86/cstate: Allow ACPI C1 FFH MWAIT use on Hygon systems
  x86/amd_nb: Add AMD family 19h model 50h PCI ids
  x86/cpu: Fix core name for Sapphire Rapids
2021-06-28 11:22:40 -07:00
Andrew Cooper
cbcddaa33d perf/x86/rapl: Use CPUID bit on AMD and Hygon parts
AMD and Hygon CPUs have a CPUID bit for RAPL.  Drop the fam17h suffix as
it is stale already.

Make use of this instead of a model check to work more nicely in virtual
environments where RAPL typically isn't available.

 [ bp: drop the ../cpu/powerflags.c hunk which is superfluous as the
   "rapl" bit name appears already in flags. ]

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210514135920.16093-1-andrew.cooper3@citrix.com
2021-06-01 21:10:33 +02:00
Linus Torvalds
ccb013c29d - Enable -Wundef for the compressed kernel build stage
- Reorganize SEV code to streamline and simplify future development
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Merge tag 'x86_urgent_for_v5.13_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:
 "The three SEV commits are not really urgent material. But we figured
  since getting them in now will avoid a huge amount of conflicts
  between future SEV changes touching tip, the kvm and probably other
  trees, sending them to you now would be best.

  The idea is that the tip, kvm etc branches for 5.14 will all base
  ontop of -rc2 and thus everything will be peachy. What is more, those
  changes are purely mechanical and defines movement so they should be
  fine to go now (famous last words).

  Summary:

   - Enable -Wundef for the compressed kernel build stage

   - Reorganize SEV code to streamline and simplify future development"

* tag 'x86_urgent_for_v5.13_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/compressed: Enable -Wundef
  x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG
  x86/sev: Move GHCB MSR protocol and NAE definitions in a common header
  x86/sev-es: Rename sev-es.{ch} to sev.{ch}
2021-05-16 09:31:06 -07:00
Huang Rui
3743d55b28 x86, sched: Fix the AMD CPPC maximum performance value on certain AMD Ryzen generations
Some AMD Ryzen generations has different calculation method on maximum
performance. 255 is not for all ASICs, some specific generations should use 166
as the maximum performance. Otherwise, it will report incorrect frequency value
like below:

  ~ → lscpu | grep MHz
  CPU MHz:                         3400.000
  CPU max MHz:                     7228.3198
  CPU min MHz:                     2200.0000

[ mingo: Tidied up whitespace use. ]
[ Alexander Monakov <amonakov@ispras.ru>: fix 225 -> 255 typo. ]

Fixes: 41ea667227 ("x86, sched: Calculate frequency invariance for AMD systems")
Fixes: 3c55e94c0a ("cpufreq: ACPI: Extend frequency tables to cover boost frequencies")
Reported-by: Jason Bagavatsingham <jason.bagavatsingham@gmail.com>
Fixed-by: Alexander Monakov <amonakov@ispras.ru>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jason Bagavatsingham <jason.bagavatsingham@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210425073451.2557394-1-ray.huang@amd.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211791
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-05-13 12:10:24 +02:00
Brijesh Singh
059e5c321a x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG
The SYSCFG MSR continued being updated beyond the K8 family; drop the K8
name from it.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lkml.kernel.org/r/20210427111636.1207-4-brijesh.singh@amd.com
2021-05-10 07:51:38 +02:00
Peter Zijlstra
a89dfde3dc x86: Remove dynamic NOP selection
This ensures that a NOP is a NOP and not a random other instruction that
is also a NOP. It allows simplification of dynamic code patching that
wants to verify existing code before writing new instructions (ftrace,
jump_label, static_call, etc..).

Differentiating on NOPs is not a feature.

This pessimises 32bit (DONTCARE) and 32bit on 64bit CPUs (CARELESS).
32bit is not a performance target.

Everything x86_64 since AMD K10 (2007) and Intel IvyBridge (2012) is
fine with using NOPL (as opposed to prefix NOP). And per FEATURE_NOPL
being required for x86_64, all x86_64 CPUs can use NOPL. So stop
caring about NOPs, simplify things and get on with life.

[ The problem seems to be that some uarchs can only decode NOPL on a
single front-end port while others have severe decode penalties for
excessive prefixes. All modern uarchs can handle both, except Atom,
which has prefix penalties. ]

[ Also, much doubt you can actually measure any of this on normal
workloads. ]

After this, FEATURE_NOPL is unused except for required-features for
x86_64. FEATURE_K8 is only used for PTI.

 [ bp: Kernel build measurements showed ~0.3s slowdown on Sandybridge
   which is hardly a slowdown. Get rid of X86_FEATURE_K7, while at it. ]

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> # bpf
Acked-by: Linus Torvalds <torvalds@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20210312115749.065275711@infradead.org
2021-03-15 16:24:59 +01:00
Yazen Ghannam
76e2fc63ca x86/cpu/amd: Set __max_die_per_package on AMD
Set the maximum DIE per package variable on AMD using the
NodesPerProcessor topology value. This will be used by RAPL, among
others, to determine the maximum number of DIEs on the system in order
to do per-DIE manipulations.

 [ bp: Productize into a proper patch. ]

Fixes: 028c221ed1 ("x86/CPU/AMD: Save AMD NodeId as cpu_die_id")
Reported-by: Johnathan Smithinovic <johnathan.smithinovic@gmx.at>
Reported-by: Rafael Kitover <rkitover@gmail.com>
Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Johnathan Smithinovic <johnathan.smithinovic@gmx.at>
Tested-by: Rafael Kitover <rkitover@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=210939
Link: https://lkml.kernel.org/r/20210106112106.GE5729@zn.tnic
Link: https://lkml.kernel.org/r/20210111101455.1194-1-bp@alien8.de
2021-01-12 12:21:01 +01:00
Arvind Sankar
262bd5724a x86/cpu/amd: Remove dead code for TSEG region remapping
Commit

  26bfa5f894 ("x86, amd: Cleanup init_amd")

moved the code that remaps the TSEG region using 4k pages from
init_amd() to bsp_init_amd().

However, bsp_init_amd() is executed well before the direct mapping is
actually created:

  setup_arch()
    -> early_cpu_init()
      -> early_identify_cpu()
        -> this_cpu->c_bsp_init()
	  -> bsp_init_amd()
    ...
    -> init_mem_mapping()

So the change effectively disabled the 4k remapping, because
pfn_range_is_mapped() is always false at this point.

It has been over six years since the commit, and no-one seems to have
noticed this, so just remove the code. The original code was also
incomplete, since it doesn't check how large the TSEG address range
actually is, so it might remap only part of it in any case.

Hygon has copied the incorrect version, so the code has never run on it
since the cpu support was added two years ago. Remove it from there as
well.

Committer notes:

This workaround is incomplete anyway:

1. The code must check MSRC001_0113.TValid (SMM TSeg Mask MSR) first, to
check whether the TSeg address range is enabled.

2. The code must check whether the range is not 2M aligned - if it is,
there's nothing to work around.

3. In all the BIOSes tested, the TSeg range is in a e820 reserved area
and those are not mapped anymore, after

  66520ebc2d ("x86, mm: Only direct map addresses that are marked as E820_RAM")

which means, there's nothing to be worked around either.

So let's rip it out.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201127171324.1846019-1-nivedita@alum.mit.edu
2020-12-08 18:45:21 +01:00
Yazen Ghannam
db970bd231 x86/CPU/AMD: Remove amd_get_nb_id()
The Last Level Cache ID is returned by amd_get_nb_id(). In practice,
this value is the same as the AMD NodeId for callers of this function.
The NodeId is saved in struct cpuinfo_x86.cpu_die_id.

Replace calls to amd_get_nb_id() with the logical CPU's cpu_die_id and
remove the function.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201109210659.754018-3-Yazen.Ghannam@amd.com
2020-11-19 11:43:17 +01:00
Yazen Ghannam
028c221ed1 x86/CPU/AMD: Save AMD NodeId as cpu_die_id
AMD systems provide a "NodeId" value that represents a global ID
indicating to which "Node" a logical CPU belongs. The "Node" is a
physical structure equivalent to a Die, and it should not be confused
with logical structures like NUMA nodes. Logical nodes can be adjusted
based on firmware or other settings whereas the physical nodes/dies are
fixed based on hardware topology.

The NodeId value can be used when a physical ID is needed by software.

Save the AMD NodeId to struct cpuinfo_x86.cpu_die_id. Use the value
from CPUID or MSR as appropriate. Default to phys_proc_id otherwise.
Do so for both AMD and Hygon systems.

Drop the node_id parameter from cacheinfo_*_init_llc_id() as it is no
longer needed.

Update the x86 topology documentation.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201109210659.754018-2-Yazen.Ghannam@amd.com
2020-11-19 11:43:13 +01:00
Tom Lendacky
360e7c5c4c x86/cpufeatures: Add SEV-ES CPU feature
Add CPU feature detection for Secure Encrypted Virtualization with
Encrypted State. This feature enhances SEV by also encrypting the
guest register state, making it in-accessible to the hypervisor.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907131613.12703-6-joro@8bytes.org
2020-09-07 19:45:24 +02:00
Peter Zijlstra
0cd39f4600 locking/seqlock, headers: Untangle the spaghetti monster
By using lockdep_assert_*() from seqlock.h, the spaghetti monster
attacked.

Attack back by reducing seqlock.h dependencies from two key high level headers:

 - <linux/seqlock.h>:               -Remove <linux/ww_mutex.h>
 - <linux/time.h>:                  -Remove <linux/seqlock.h>
 - <linux/sched.h>:                 +Add    <linux/seqlock.h>

The price was to add it to sched.h ...

Core header fallout, we add direct header dependencies instead of gaining them
parasitically from higher level headers:

 - <linux/dynamic_queue_limits.h>:  +Add <asm/bug.h>
 - <linux/hrtimer.h>:               +Add <linux/seqlock.h>
 - <linux/ktime.h>:                 +Add <asm/bug.h>
 - <linux/lockdep.h>:               +Add <linux/smp.h>
 - <linux/sched.h>:                 +Add <linux/seqlock.h>
 - <linux/videodev2.h>:             +Add <linux/kernel.h>

Arch headers fallout:

 - PARISC: <asm/timex.h>:           +Add <asm/special_insns.h>
 - SH:     <asm/io.h>:              +Add <asm/page.h>
 - SPARC:  <asm/timer_64.h>:        +Add <uapi/asm/asi.h>
 - SPARC:  <asm/vvar.h>:            +Add <asm/processor.h>, <asm/barrier.h>
                                    -Remove <linux/seqlock.h>
 - X86:    <asm/fixmap.h>:          +Add <asm/pgtable_types.h>
                                    -Remove <asm/acpi.h>

There's also a bunch of parasitic header dependency fallout in .c files, not listed
separately.

[ mingo: Extended the changelog, split up & fixed the original patch. ]

Co-developed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200804133438.GK2674@hirez.programming.kicks-ass.net
2020-08-06 16:13:13 +02:00
Linus Torvalds
eff5ddadab Misc updates:
- Extend the x86 family/model macros with a steppings dimension,
    because x86 life isn't complex enough and Intel uses steppings to
    differentiate between different CPUs. :-/
 
  - Convert the TSC deadline timer quirks to the steppings macros.
 
  - Clean up asm mnemonics.
 
  - Fix the handling of an AMD erratum, or in other words, fix a kernel erratum.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'x86-cpu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpu updates from Ingo Molnar:
 "Misc updates:

   - Extend the x86 family/model macros with a steppings dimension,
     because x86 life isn't complex enough and Intel uses steppings to
     differentiate between different CPUs. :-/

   - Convert the TSC deadline timer quirks to the steppings macros.

   - Clean up asm mnemonics.

   - Fix the handling of an AMD erratum, or in other words, fix a kernel
     erratum"

* tag 'x86-cpu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Use RDRAND and RDSEED mnemonics in archrandom.h
  x86/cpu: Use INVPCID mnemonic in invpcid.h
  x86/cpu/amd: Make erratum #1054 a legacy erratum
  x86/apic: Convert the TSC deadline timer matching to steppings macro
  x86/cpu: Add a X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS() macro
  x86/cpu: Add a steppings field to struct x86_cpu_id
2020-06-01 13:57:51 -07:00
Kim Phillips
e2abfc0448 x86/cpu/amd: Make erratum #1054 a legacy erratum
Commit

  21b5ee59ef ("x86/cpu/amd: Enable the fixed Instructions Retired
		 counter IRPERF")

mistakenly added erratum #1054 as an OS Visible Workaround (OSVW) ID 0.
Erratum #1054 is not OSVW ID 0 [1], so make it a legacy erratum.

There would never have been a false positive on older hardware that
has OSVW bit 0 set, since the IRPERF feature was not available.

However, save a couple of RDMSR executions per thread, on modern
system configurations that correctly set non-zero values in their
OSVW_ID_Length MSRs.

[1] Revision Guide for AMD Family 17h Models 00h-0Fh Processors. The
revision guide is available from the bugzilla link below.

Fixes: 21b5ee59ef ("x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERF")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200417143356.26054-1-kim.phillips@amd.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
2020-05-07 17:30:14 +02:00
Reinette Chatre
923f3a2b48 x86/resctrl: Query LLC monitoring properties once during boot
Cache and memory bandwidth monitoring are features that are part of
x86 CPU resource control that is supported by the resctrl subsystem.
The monitoring properties are obtained via CPUID from every CPU
and only used within the resctrl subsystem where the properties are
only read from boot_cpu_data.

Obtain the monitoring properties once, placed in boot_cpu_data, via the
->c_bsp_init() helpers of the vendors that support X86_FEATURE_CQM_LLC.

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/6d74a6ac3e69f4b7a8b4115835f9455faf0f468d.1588715690.git.reinette.chatre@intel.com
2020-05-06 17:58:08 +02:00
Linus Torvalds
9b82f05f86 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main changes in this cycle were:

  Kernel side changes:

   - A couple of x86/cpu cleanups and changes were grandfathered in due
     to patch dependencies. These clean up the set of CPU model/family
     matching macros with a consistent namespace and C99 initializer
     style.

   - A bunch of updates to various low level PMU drivers:
       * AMD Family 19h L3 uncore PMU
       * Intel Tiger Lake uncore support
       * misc fixes to LBR TOS sampling

   - optprobe fixes

   - perf/cgroup: optimize cgroup event sched-in processing

   - misc cleanups and fixes

  Tooling side changes are to:

   - perf {annotate,expr,record,report,stat,test}

   - perl scripting

   - libapi, libperf and libtraceevent

   - vendor events on Intel and S390, ARM cs-etm

   - Intel PT updates

   - Documentation changes and updates to core facilities

   - misc cleanups, fixes and other enhancements"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (89 commits)
  cpufreq/intel_pstate: Fix wrong macro conversion
  x86/cpu: Cleanup the now unused CPU match macros
  hwrng: via_rng: Convert to new X86 CPU match macros
  crypto: Convert to new CPU match macros
  ASoC: Intel: Convert to new X86 CPU match macros
  powercap/intel_rapl: Convert to new X86 CPU match macros
  PCI: intel-mid: Convert to new X86 CPU match macros
  mmc: sdhci-acpi: Convert to new X86 CPU match macros
  intel_idle: Convert to new X86 CPU match macros
  extcon: axp288: Convert to new X86 CPU match macros
  thermal: Convert to new X86 CPU match macros
  hwmon: Convert to new X86 CPU match macros
  platform/x86: Convert to new CPU match macros
  EDAC: Convert to new X86 CPU match macros
  cpufreq: Convert to new X86 CPU match macros
  ACPI: Convert to new X86 CPU match macros
  x86/platform: Convert to new CPU match macros
  x86/kernel: Convert to new CPU match macros
  x86/kvm: Convert to new CPU match macros
  x86/perf/events: Convert to new CPU match macros
  ...
2020-03-30 16:40:08 -07:00
Linus Torvalds
ff7b862a4c * Do not report spurious MCEs on some Intel platforms caused by errata;
by Prarit Bhargava.
 
 * Change dev-mcelog's hardcoded limit of 32 error records to a dynamic
 one, controlled by the number of logical CPUs, by Tony Luck.
 
 * Add support for the processor identification number (PPIN) on AMD, by
 Wei Huang.
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Merge tag 'ras_updates_for_5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS updates from Borislav Petkov:

 - Do not report spurious MCEs on some Intel platforms caused by errata;
   by Prarit Bhargava.

 - Change dev-mcelog's hardcoded limit of 32 error records to a dynamic
   one, controlled by the number of logical CPUs, by Tony Luck.

 - Add support for the processor identification number (PPIN) on AMD, by
   Wei Huang.

* tag 'ras_updates_for_5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/amd: Add PPIN support for AMD MCE
  x86/mce/dev-mcelog: Dynamically allocate space for machine check records
  x86/mce: Do not log spurious corrected mce errors
2020-03-30 13:17:50 -07:00
Ingo Molnar
629b3df7ec Merge branch 'x86/cpu' into perf/core, to resolve conflict
Conflicts:
	arch/x86/events/intel/uncore.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-25 15:20:44 +01:00
Wei Huang
077168e241 x86/mce/amd: Add PPIN support for AMD MCE
Newer AMD CPUs support a feature called protected processor
identification number (PPIN). This feature can be detected via
CPUID_Fn80000008_EBX[23].

However, CPUID alone is not enough to read the processor identification
number - MSR_AMD_PPIN_CTL also needs to be configured properly. If, for
any reason, MSR_AMD_PPIN_CTL[PPIN_EN] can not be turned on, such as
disabled in BIOS, the CPU capability bit X86_FEATURE_AMD_PPIN needs to
be cleared.

When the X86_FEATURE_AMD_PPIN capability is available, the
identification number is issued together with the MCE error info in
order to keep track of the source of MCE errors.

 [ bp: Massage. ]

Co-developed-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com>
Signed-off-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com>
Signed-off-by: Wei Huang <wei.huang2@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200321193800.3666964-1-wei.huang2@amd.com
2020-03-22 11:03:47 +01:00
Kim Phillips
753039ef8b x86/cpu/amd: Call init_amd_zn() om Family 19h processors too
Family 19h CPUs are Zen-based and still share most architectural
features with Family 17h CPUs, and therefore still need to call
init_amd_zn() e.g., to set the RECLAIM_DISTANCE override.

init_amd_zn() also sets X86_FEATURE_ZEN, which today is only used
in amd_set_core_ssb_state(), which isn't called on some late
model Family 17h CPUs, nor on any Family 19h CPUs:
X86_FEATURE_AMD_SSBD replaces X86_FEATURE_LS_CFG_SSBD on those
later model CPUs, where the SSBD mitigation is done via the
SPEC_CTRL MSR instead of the LS_CFG MSR.

Family 19h CPUs also don't have the erratum where the CPB feature
bit isn't set, but that code can stay unchanged and run safely
on Family 19h.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200311191451.13221-1-kim.phillips@amd.com
2020-03-12 12:13:44 +01:00
Kim Phillips
21b5ee59ef x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERF
Commit

  aaf248848d ("perf/x86/msr: Add AMD IRPERF (Instructions Retired)
		  performance counter")

added support for access to the free-running counter via 'perf -e
msr/irperf/', but when exercised, it always returns a 0 count:

BEFORE:

  $ perf stat -e instructions,msr/irperf/ true

   Performance counter stats for 'true':

             624,833      instructions
                   0      msr/irperf/

Simply set its enable bit - HWCR bit 30 - to make it start counting.

Enablement is restricted to all machines advertising IRPERF capability,
except those susceptible to an erratum that makes the IRPERF return
bad values.

That erratum occurs in Family 17h models 00-1fh [1], but not in F17h
models 20h and above [2].

AFTER (on a family 17h model 31h machine):

  $ perf stat -e instructions,msr/irperf/ true

   Performance counter stats for 'true':

             621,690      instructions
             622,490      msr/irperf/

[1] Revision Guide for AMD Family 17h Models 00h-0Fh Processors
[2] Revision Guide for AMD Family 17h Models 30h-3Fh Processors

The revision guides are available from the bugzilla Link below.

 [ bp: Massage commit message. ]

Fixes: aaf248848d ("perf/x86/msr: Add AMD IRPERF (Instructions Retired) performance counter")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
Link: http://lkml.kernel.org/r/20200214201805.13830-1-kim.phillips@amd.com
2020-02-19 20:01:54 +01:00
Linus Torvalds
6da49d1abd Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups all around the map"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/CPU/AMD: Remove amd_get_topology_early()
  x86/tsc: Remove redundant assignment
  x86/crash: Use resource_size()
  x86/cpu: Add a missing prototype for arch_smt_update()
  x86/nospec: Remove unused RSB_FILL_LOOPS
  x86/vdso: Provide missing include file
  x86/Kconfig: Correct spelling and punctuation
  Documentation/x86/boot: Fix typo
  x86/boot: Fix a comment's incorrect file reference
  x86/process: Remove set but not used variables prev and next
  x86/Kconfig: Fix Kconfig indentation
2020-01-28 12:11:23 -08:00
Borislav Petkov
3c749b81ee x86/CPU/AMD: Remove amd_get_topology_early()
... and fold its function body into its single call site.

No functional changes:

  # arch/x86/kernel/cpu/amd.o:

   text    data     bss     dec     hex filename
   5994     385       1    6380    18ec amd.o.before
   5994     385       1    6380    18ec amd.o.after

md5:
   99ec6daa095b502297884e949c520f90  amd.o.before.asm
   99ec6daa095b502297884e949c520f90  amd.o.after.asm

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200123165811.5288-1-bp@alien8.de
2020-01-25 12:59:46 +01:00
Tom Lendacky
a006483b2f x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained
If the SME and SEV features are present via CPUID, but memory encryption
support is not enabled (MSR 0xC001_0010[23]), the feature flags are cleared
using clear_cpu_cap(). However, if get_cpu_cap() is later called, these
feature flags will be reset back to present, which is not desired.

Change from using clear_cpu_cap() to setup_clear_cpu_cap() so that the
clearing of the flags is maintained.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # 4.16.x-
Link: https://lkml.kernel.org/r/226de90a703c3c0be5a49565047905ac4e94e8f3.1579125915.git.thomas.lendacky@amd.com
2020-01-16 20:23:20 +01:00
Linus Torvalds
22331f8952 Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu-feature updates from Ingo Molnar:

 - Rework the Intel model names symbols/macros, which were decades of
   ad-hoc extensions and added random noise. It's now a coherent, easy
   to follow nomenclature.

 - Add new Intel CPU model IDs:
    - "Tiger Lake" desktop and mobile models
    - "Elkhart Lake" model ID
    - and the "Lightning Mountain" variant of Airmont, plus support code

 - Add the new AVX512_VP2INTERSECT instruction to cpufeatures

 - Remove Intel MPX user-visible APIs and the self-tests, because the
   toolchain (gcc) is not supporting it going forward. This is the
   first, lowest-risk phase of MPX removal.

 - Remove X86_FEATURE_MFENCE_RDTSC

 - Various smaller cleanups and fixes

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  x86/cpu: Update init data for new Airmont CPU model
  x86/cpu: Add new Airmont variant to Intel family
  x86/cpu: Add Elkhart Lake to Intel family
  x86/cpu: Add Tiger Lake to Intel family
  x86: Correct misc typos
  x86/intel: Add common OPTDIFFs
  x86/intel: Aggregate microserver naming
  x86/intel: Aggregate big core graphics naming
  x86/intel: Aggregate big core mobile naming
  x86/intel: Aggregate big core client naming
  x86/cpufeature: Explain the macro duplication
  x86/ftrace: Remove mcount() declaration
  x86/PCI: Remove superfluous returns from void functions
  x86/msr-index: Move AMD MSRs where they belong
  x86/cpu: Use constant definitions for CPU models
  lib: Remove redundant ftrace flag removal
  x86/crash: Remove unnecessary comparison
  x86/bitops: Use __builtin_constant_p() directly instead of IS_IMMEDIATE()
  x86: Remove X86_FEATURE_MFENCE_RDTSC
  x86/mpx: Remove MPX APIs
  ...
2019-09-16 18:47:53 -07:00
Linus Torvalds
7e67a85999 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
   Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
   Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.

   As perf and the scheduler is getting bigger and more complex,
   document the status quo of current responsibilities and interests,
   and spread the review pain^H^H^H^H fun via an increase in the Cc:
   linecount generated by scripts/get_maintainer.pl. :-)

 - Add another series of patches that brings the -rt (PREEMPT_RT) tree
   closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
   into a new CONFIG_PREEMPTION category that will allow the eventual
   introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
   to go though.

 - Extend the CPU cgroup controller with uclamp.min and uclamp.max to
   allow the finer shaping of CPU bandwidth usage.

 - Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).

 - Improve the behavior of high CPU count, high thread count
   applications running under cpu.cfs_quota_us constraints.

 - Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.

 - Improve CPU isolation housekeeping CPU allocation NUMA locality.

 - Fix deadline scheduler bandwidth calculations and logic when cpusets
   rebuilds the topology, or when it gets deadline-throttled while it's
   being offlined.

 - Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
   setscheduler() system calls without creating global serialization.
   Add new synchronization between cpuset topology-changing events and
   the deadline acceptance tests in setscheduler(), which were broken
   before.

 - Rework the active_mm state machine to be less confusing and more
   optimal.

 - Rework (simplify) the pick_next_task() slowpath.

 - Improve load-balancing on AMD EPYC systems.

 - ... and misc cleanups, smaller fixes and improvements - please see
   the Git log for more details.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
  sched/psi: Correct overly pessimistic size calculation
  sched/fair: Speed-up energy-aware wake-ups
  sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
  sched/uclamp: Update CPU's refcount on TG's clamp changes
  sched/uclamp: Use TG's clamps to restrict TASK's clamps
  sched/uclamp: Propagate system defaults to the root group
  sched/uclamp: Propagate parent clamps
  sched/uclamp: Extend CPU's cgroup controller
  sched/topology: Improve load balancing on AMD EPYC systems
  arch, ia64: Make NUMA select SMP
  sched, perf: MAINTAINERS update, add submaintainers and reviewers
  sched/fair: Use rq_lock/unlock in online_fair_sched_group
  cpufreq: schedutil: fix equation in comment
  sched: Rework pick_next_task() slow-path
  sched: Allow put_prev_task() to drop rq->lock
  sched/fair: Expose newidle_balance()
  sched: Add task_struct pointer to sched_class::set_curr_task
  sched: Rework CPU hotplug task selection
  sched/{rt,deadline}: Fix set_next_task vs pick_next_task
  sched: Fix kerneldoc comment for ia64_set_curr_task
  ...
2019-09-16 17:25:49 -07:00
Matt Fleming
a55c7454a8 sched/topology: Improve load balancing on AMD EPYC systems
SD_BALANCE_{FORK,EXEC} and SD_WAKE_AFFINE are stripped in sd_init()
for any sched domains with a NUMA distance greater than 2 hops
(RECLAIM_DISTANCE). The idea being that it's expensive to balance
across domains that far apart.

However, as is rather unfortunately explained in:

  commit 32e45ff43e ("mm: increase RECLAIM_DISTANCE to 30")

the value for RECLAIM_DISTANCE is based on node distance tables from
2011-era hardware.

Current AMD EPYC machines have the following NUMA node distances:

 node distances:
 node   0   1   2   3   4   5   6   7
   0:  10  16  16  16  32  32  32  32
   1:  16  10  16  16  32  32  32  32
   2:  16  16  10  16  32  32  32  32
   3:  16  16  16  10  32  32  32  32
   4:  32  32  32  32  10  16  16  16
   5:  32  32  32  32  16  10  16  16
   6:  32  32  32  32  16  16  10  16
   7:  32  32  32  32  16  16  16  10

where 2 hops is 32.

The result is that the scheduler fails to load balance properly across
NUMA nodes on different sockets -- 2 hops apart.

For example, pinning 16 busy threads to NUMA nodes 0 (CPUs 0-7) and 4
(CPUs 32-39) like so,

  $ numactl -C 0-7,32-39 ./spinner 16

causes all threads to fork and remain on node 0 until the active
balancer kicks in after a few seconds and forcibly moves some threads
to node 4.

Override node_reclaim_distance for AMD Zen.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suravee.Suthikulpanit@amd.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas.Lendacky@amd.com
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20190808195301.13222-3-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-09-03 09:17:37 +02:00
Ingo Molnar
b3e30c9884 Linux 5.3-rc6
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Merge tag 'v5.3-rc6' into x86/cpu, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-08-26 11:20:55 +02:00
Tom Lendacky
c49a0a8013 x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h
There have been reports of RDRAND issues after resuming from suspend on
some AMD family 15h and family 16h systems. This issue stems from a BIOS
not performing the proper steps during resume to ensure RDRAND continues
to function properly.

RDRAND support is indicated by CPUID Fn00000001_ECX[30]. This bit can be
reset by clearing MSR C001_1004[62]. Any software that checks for RDRAND
support using CPUID, including the kernel, will believe that RDRAND is
not supported.

Update the CPU initialization to clear the RDRAND CPUID bit for any family
15h and 16h processor that supports RDRAND. If it is known that the family
15h or family 16h system does not have an RDRAND resume issue or that the
system will not be placed in suspend, the "rdrand=force" kernel parameter
can be used to stop the clearing of the RDRAND CPUID bit.

Additionally, update the suspend and resume path to save and restore the
MSR C001_1004 value to ensure that the RDRAND CPUID setting remains in
place after resuming from suspend.

Note, that clearing the RDRAND CPUID bit does not prevent a processor
that normally supports the RDRAND instruction from executing it. So any
code that determined the support based on family and model won't #UD.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chen Yu <yu.c.chen@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>
Cc: "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "x86@kernel.org" <x86@kernel.org>
Link: https://lkml.kernel.org/r/7543af91666f491547bd86cebb1e17c66824ab9f.1566229943.git.thomas.lendacky@amd.com
2019-08-19 19:42:52 +02:00
Josh Poimboeuf
be261ffce6 x86: Remove X86_FEATURE_MFENCE_RDTSC
AMD and Intel both have serializing lfence (X86_FEATURE_LFENCE_RDTSC).
They've both had it for a long time, and AMD has had it enabled in Linux
since Spectre v1 was announced.

Back then, there was a proposal to remove the serializing mfence feature
bit (X86_FEATURE_MFENCE_RDTSC), since both AMD and Intel have
serializing lfence.  At the time, it was (ahem) speculated that some
hypervisors might not yet support its removal, so it remained for the
time being.

Now a year-and-a-half later, it should be safe to remove.

I asked Andrew Cooper about whether it's still needed:

  So if you're virtualised, you've got no choice in the matter.  lfence
  is either dispatch-serialising or not on AMD, and you won't be able to
  change it.

  Furthermore, you can't accurately tell what state the bit is in, because
  the MSR might not be virtualised at all, or may not reflect the true
  state in hardware.  Worse still, attempting to set the bit may not be
  successful even if there isn't a fault for doing so.

  Xen sets the DE_CFG bit unconditionally, as does Linux by the looks of
  things (see MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT).  ISTR other hypervisor
  vendors saying the same, but I don't have any information to hand.

  If you are running under a hypervisor which has been updated, then
  lfence will almost certainly be dispatch-serialising in practice, and
  you'll almost certainly see the bit already set in DE_CFG.  If you're
  running under a hypervisor which hasn't been patched since Spectre,
  you've already lost in many more ways.

  I'd argue that X86_FEATURE_MFENCE_RDTSC is not worth keeping.

So remove it.  This will reduce some code rot, and also make it easier
to hook barrier_nospec() up to a cmdline disable for performance
raisins, without having to need an alternative_3() macro.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/d990aa51e40063acb9888e8c1b688e41355a9588.1562255067.git.jpoimboe@redhat.com
2019-07-22 12:00:51 +02:00
Frank van der Linden
2ac44ab608 x86/CPU/AMD: Don't force the CPB cap when running under a hypervisor
For F17h AMD CPUs, the CPB capability ('Core Performance Boost') is forcibly set,
because some versions of that chip incorrectly report that they do not have it.

However, a hypervisor may filter out the CPB capability, for good
reasons. For example, KVM currently does not emulate setting the CPB
bit in MSR_K7_HWCR, and unchecked MSR access errors will be thrown
when trying to set it as a guest:

	unchecked MSR access error: WRMSR to 0xc0010015 (tried to write 0x0000000001000011) at rIP: 0xffffffff890638f4 (native_write_msr+0x4/0x20)

	Call Trace:
	boost_set_msr+0x50/0x80 [acpi_cpufreq]
	cpuhp_invoke_callback+0x86/0x560
	sort_range+0x20/0x20
	cpuhp_thread_fun+0xb0/0x110
	smpboot_thread_fn+0xef/0x160
	kthread+0x113/0x130
	kthread_create_worker_on_cpu+0x70/0x70
	ret_from_fork+0x35/0x40

To avoid this issue, don't forcibly set the CPB capability for a CPU
when running under a hypervisor.

Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: jiaxun.yang@flygoat.com
Fixes: 0237199186 ("x86/CPU/AMD: Set the CPB bit unconditionally on F17h")
Link: http://lkml.kernel.org/r/20190522221745.GA15789@dev-dsk-fllinden-2c-c1893d73.us-west-2.amazon.com
[ Minor edits to the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 08:50:32 +02:00
Thomas Gleixner
457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Andi Kleen
26b31f46f0 x86/cpu/amd: Exclude 32bit only assembler from 64bit build
The "vide" inline assembler is only needed on 32bit kernels for old
32bit only CPUs.

Guard it with an #ifdef so it's not included in 64bit builds.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190330004743.29541-2-andi@firstfloor.org
2019-04-19 17:47:35 +02:00
Andi Kleen
c03e27506a x86/asm: Mark all top level asm statements as .text
With gcc toplevel assembler statements that do not mark themselves as .text
may end up in other sections. This causes LTO boot crashes because various
assembler statements ended up in the middle of the initcall section. It's
also a latent problem without LTO, although it's currently not known to
cause any real problems.

According to the gcc team it's expected behavior.

Always mark all the top level assembler statements as text so that they
switch to the right section.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190330004743.29541-1-andi@firstfloor.org
2019-04-19 17:46:55 +02:00
Jiaxun Yang
0237199186 x86/CPU/AMD: Set the CPB bit unconditionally on F17h
Some F17h models do not have CPB set in CPUID even though the CPU
supports it. Set the feature bit unconditionally on all F17h.

 [ bp: Rewrite commit message and patch. ]

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181120030018.5185-1-jiaxun.yang@flygoat.com
2019-01-18 16:44:03 +01:00
Borislav Petkov
ad3bc25a32 x86/kernel: Fix more -Wmissing-prototypes warnings
... with the goal of eventually enabling -Wmissing-prototypes by
default. At least on x86.

Make functions static where possible, otherwise add prototypes or make
them visible through includes.

asm/trace/ changes courtesy of Steven Rostedt <rostedt@goodmis.org>.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> # ACPI + cpufreq bits
Cc: Andrew Banman <andrew.banman@hpe.com>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yi Wang <wang.yi59@zte.com.cn>
Cc: linux-acpi@vger.kernel.org
2018-12-08 12:24:35 +01:00
Nathan Chancellor
88296bd42b x86/cpu/amd: Remove unnecessary parentheses
Clang warns when multiple pairs of parentheses are used for a single
conditional statement.

arch/x86/kernel/cpu/amd.c:925:14: warning: equality comparison with
extraneous parentheses [-Wparentheses-equality]
        if ((c->x86 == 6)) {
             ~~~~~~~^~~~
arch/x86/kernel/cpu/amd.c:925:14: note: remove extraneous parentheses
around the comparison to silence this warning
        if ((c->x86 == 6)) {
            ~       ^   ~
arch/x86/kernel/cpu/amd.c:925:14: note: use '=' to turn this equality
comparison into an assignment
        if ((c->x86 == 6)) {
                    ^~
                    =
1 warning generated.

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181002224511.14929-1-natechancellor@gmail.com
Link: https://github.com/ClangBuiltLinux/linux/issues/187
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-03 08:27:47 +02:00
Linus Torvalds
958f338e96 Merge branch 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Merge L1 Terminal Fault fixes from Thomas Gleixner:
 "L1TF, aka L1 Terminal Fault, is yet another speculative hardware
  engineering trainwreck. It's a hardware vulnerability which allows
  unprivileged speculative access to data which is available in the
  Level 1 Data Cache when the page table entry controlling the virtual
  address, which is used for the access, has the Present bit cleared or
  other reserved bits set.

  If an instruction accesses a virtual address for which the relevant
  page table entry (PTE) has the Present bit cleared or other reserved
  bits set, then speculative execution ignores the invalid PTE and loads
  the referenced data if it is present in the Level 1 Data Cache, as if
  the page referenced by the address bits in the PTE was still present
  and accessible.

  While this is a purely speculative mechanism and the instruction will
  raise a page fault when it is retired eventually, the pure act of
  loading the data and making it available to other speculative
  instructions opens up the opportunity for side channel attacks to
  unprivileged malicious code, similar to the Meltdown attack.

  While Meltdown breaks the user space to kernel space protection, L1TF
  allows to attack any physical memory address in the system and the
  attack works across all protection domains. It allows an attack of SGX
  and also works from inside virtual machines because the speculation
  bypasses the extended page table (EPT) protection mechanism.

  The assoicated CVEs are: CVE-2018-3615, CVE-2018-3620, CVE-2018-3646

  The mitigations provided by this pull request include:

   - Host side protection by inverting the upper address bits of a non
     present page table entry so the entry points to uncacheable memory.

   - Hypervisor protection by flushing L1 Data Cache on VMENTER.

   - SMT (HyperThreading) control knobs, which allow to 'turn off' SMT
     by offlining the sibling CPU threads. The knobs are available on
     the kernel command line and at runtime via sysfs

   - Control knobs for the hypervisor mitigation, related to L1D flush
     and SMT control. The knobs are available on the kernel command line
     and at runtime via sysfs

   - Extensive documentation about L1TF including various degrees of
     mitigations.

  Thanks to all people who have contributed to this in various ways -
  patches, review, testing, backporting - and the fruitful, sometimes
  heated, but at the end constructive discussions.

  There is work in progress to provide other forms of mitigations, which
  might be less horrible performance wise for a particular kind of
  workloads, but this is not yet ready for consumption due to their
  complexity and limitations"

* 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
  x86/microcode: Allow late microcode loading with SMT disabled
  tools headers: Synchronise x86 cpufeatures.h for L1TF additions
  x86/mm/kmmio: Make the tracer robust against L1TF
  x86/mm/pat: Make set_memory_np() L1TF safe
  x86/speculation/l1tf: Make pmd/pud_mknotpresent() invert
  x86/speculation/l1tf: Invert all not present mappings
  cpu/hotplug: Fix SMT supported evaluation
  KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry
  x86/speculation: Use ARCH_CAPABILITIES to skip L1D flush on vmentry
  x86/speculation: Simplify sysfs report of VMX L1TF vulnerability
  Documentation/l1tf: Remove Yonah processors from not vulnerable list
  x86/KVM/VMX: Don't set l1tf_flush_l1d from vmx_handle_external_intr()
  x86/irq: Let interrupt handlers set kvm_cpu_l1tf_flush_l1d
  x86: Don't include linux/irq.h from asm/hardirq.h
  x86/KVM/VMX: Introduce per-host-cpu analogue of l1tf_flush_l1d
  x86/irq: Demote irq_cpustat_t::__softirq_pending to u16
  x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush()
  x86/KVM/VMX: Replace 'vmx_l1d_flush_always' with 'vmx_l1d_flush_cond'
  x86/KVM/VMX: Don't set l1tf_flush_l1d to true from vmx_l1d_flush()
  cpu/hotplug: detect SMT disabled by BIOS
  ...
2018-08-14 09:46:06 -07:00