The AMD document outlining the SSBD handling
124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf
mentions that the CPUID 8000_0008.EBX[26] will mean that the
speculative store bypass disable is no longer needed.
A copy of this document is available at:
https://bugzilla.kernel.org/show_bug.cgi?id=199889
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: kvm@vger.kernel.org
Cc: andrew.cooper3@citrix.com
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lkml.kernel.org/r/20180601145921.9500-2-konrad.wilk@oracle.com
Pull x86 cache resource controller updates from Thomas Gleixner:
"An update for the Intel Resource Director Technolgy (RDT) which adds a
feedback driven software controller to runtime adjust the bandwidth
allocation MSRs.
This makes the allocations more accurate and allows to use bandwidth
values in understandable units (MB/s) instead of using percentage
based allocations as the original, still available, interface.
The software controller can be enabled with a new mount option for the
resctrl filesystem"
* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidth
x86/intel_rdt/mba_sc: Prepare for feedback loop
x86/intel_rdt/mba_sc: Add schemata support
x86/intel_rdt/mba_sc: Add initialization support
x86/intel_rdt/mba_sc: Enable/disable MBA software controller
x86/intel_rdt/mba_sc: Documentation for MBA software controller(mba_sc)
Pull x86 RAS updates from Thomas Gleixner:
- Fix a stack out of bounds write in the MCE error injection code.
- Avoid IPIs during CPU hotplug to read the MCx_MISC block address from
a remote CPU. That's fragile and pointless because the block
addresses are the same on all CPUs. So they can be read once and
local.
- Add support for MCE broadcasting on newer VIA Centaur CPUs.
* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/MCE/AMD: Read MCx_MISC block addresses on any CPU
x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read()
x86/MCE: Enable MCE broadcasting on new Centaur CPUs
Pull x86 cleanups from Ingo Molnar:
"Misc cleanups"
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apm: Fix spelling mistake: "caculate" -> "calculate"
x86/mtrr: Rename main.c to mtrr.c and remove duplicate prefixes
x86: Remove pr_fmt duplicate logging prefixes
x86/early-quirks: Rename duplicate define of dev_err
x86/bpf: Clean up non-standard comments, to make the code more readable
Pull x86 boot updates from Ingo Molnar:
- Centaur CPU updates (David Wang)
- AMD and other CPU topology enumeration improvements and fixes
(Borislav Petkov, Thomas Gleixner, Suravee Suthikulpanit)
- Continued 5-level paging work (Kirill A. Shutemov)
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Mark __pgtable_l5_enabled __initdata
x86/mm: Mark p4d_offset() __always_inline
x86/mm: Introduce the 'no5lvl' kernel parameter
x86/mm: Stop pretending pgtable_l5_enabled is a variable
x86/mm: Unify pgtable_l5_enabled usage in early boot code
x86/boot/compressed/64: Fix trampoline page table address calculation
x86/CPU: Move x86_cpuinfo::x86_max_cores assignment to detect_num_cpu_cores()
x86/Centaur: Report correct CPU/cache topology
x86/CPU: Move cpu_detect_cache_sizes() into init_intel_cacheinfo()
x86/CPU: Make intel_num_cpu_cores() generic
x86/CPU: Move cpu local function declarations to local header
x86/CPU/AMD: Derive CPU topology from CPUID function 0xB when available
x86/CPU: Modify detect_extended_topology() to return result
x86/CPU/AMD: Calculate last level cache ID from number of sharing threads
x86/CPU: Rename intel_cacheinfo.c to cacheinfo.c
perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id
x86/CPU/AMD: Have smp_num_siblings and cpu_llc_id always be present
x86/Centaur: Initialize supported CPU features properly
Pull RCU updates from Ingo Molnar:
- updates to the handling of expedited grace periods
- updates to reduce lock contention in the rcu_node combining tree
[ These are in preparation for the consolidation of RCU-bh,
RCU-preempt, and RCU-sched into a single flavor, which was
requested by Linus in response to a security flaw whose root cause
included confusion between the multiple flavors of RCU ]
- torture-test updates that save their users some time and effort
- miscellaneous fixes
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
rcu/x86: Provide early rcu_cpu_starting() callback
torture: Make kvm-find-errors.sh find build warnings
rcutorture: Abbreviate kvm.sh summary lines
rcutorture: Print end-of-test state in kvm.sh summary
rcutorture: Print end-of-test state
torture: Fold parse-torture.sh into parse-console.sh
torture: Add a script to edit output from failed runs
rcu: Update list of rcu_future_grace_period() trace events
rcu: Drop early GP request check from rcu_gp_kthread()
rcu: Simplify and inline cpu_needs_another_gp()
rcu: The rcu_gp_cleanup() function does not need cpu_needs_another_gp()
rcu: Make rcu_start_this_gp() check for out-of-range requests
rcu: Add funnel locking to rcu_start_this_gp()
rcu: Make rcu_start_future_gp() caller select grace period
rcu: Inline rcu_start_gp_advanced() into rcu_start_future_gp()
rcu: Clear request other than RCU_GP_FLAG_INIT at GP end
rcu: Cleanup, don't put ->completed into an int
rcu: Switch __rcu_process_callbacks() to rcu_accelerate_cbs()
rcu: Avoid __call_rcu_core() root rcu_node ->lock acquisition
rcu: Make rcu_migrate_callbacks wake GP kthread when needed
...
Pull RCU fix from Paul E. McKenney:
"This additional v4.18 pull request contains a single commit that fell
through the cracks:
Provide early rcu_cpu_starting() callback for the benefit of the
x86/mtrr code, which needs RCU to be available on incoming CPUs
earlier than has been the case in the past."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Only CPUs which speculate can speculate. Therefore, it seems prudent
to test for cpu_no_speculation first and only then determine whether
a specific speculating CPU is susceptible to store bypass speculation.
This is underlined by all CPUs currently listed in cpu_no_speculation
were present in cpu_no_spec_store_bypass as well.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@suse.de
Cc: konrad.wilk@oracle.com
Link: https://lkml.kernel.org/r/20180522090539.GA24668@light.dominikbrodowski.net
The x86/mtrr code does horrific things because hardware. It uses
stop_machine_from_inactive_cpu(), which does a wakeup (of the stopper
thread on another CPU), which uses RCU, all before the CPU is onlined.
RCU complains about this, because wakeups use RCU and RCU does
(rightfully) not consider offline CPUs for grace-periods.
Fix this by initializing RCU way early in the MTRR case.
Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Add !SMP support, per 0day Test Robot report. ]
Merge speculative store buffer bypass fixes from Thomas Gleixner:
- rework of the SPEC_CTRL MSR management to accomodate the new fancy
SSBD (Speculative Store Bypass Disable) bit handling.
- the CPU bug and sysfs infrastructure for the exciting new Speculative
Store Bypass 'feature'.
- support for disabling SSB via LS_CFG MSR on AMD CPUs including
Hyperthread synchronization on ZEN.
- PRCTL support for dynamic runtime control of SSB
- SECCOMP integration to automatically disable SSB for sandboxed
processes with a filter flag for opt-out.
- KVM integration to allow guests fiddling with SSBD including the new
software MSR VIRT_SPEC_CTRL to handle the LS_CFG based oddities on
AMD.
- BPF protection against SSB
.. this is just the core and x86 side, other architecture support will
come separately.
* 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits)
bpf: Prevent memory disambiguation attack
x86/bugs: Rename SSBD_NO to SSB_NO
KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBD
x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFG
x86/bugs: Rework spec_ctrl base and mask logic
x86/bugs: Remove x86_spec_ctrl_set()
x86/bugs: Expose x86_spec_ctrl_base directly
x86/bugs: Unify x86_spec_ctrl_{set_guest,restore_host}
x86/speculation: Rework speculative_store_bypass_update()
x86/speculation: Add virtualized speculative store bypass disable support
x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRL
x86/speculation: Handle HT correctly on AMD
x86/cpufeatures: Add FEATURE_ZEN
x86/cpufeatures: Disentangle SSBD enumeration
x86/cpufeatures: Disentangle MSR_SPEC_CTRL enumeration from IBRS
x86/speculation: Use synthetic bits for IBRS/IBPB/STIBP
KVM: SVM: Move spec control call after restore of GS
x86/cpu: Make alternative_msr_write work for 32-bit code
x86/bugs: Fix the parameters alignment and missing void
x86/bugs: Make cpu_show_common() static
...
We used rdmsr_safe_on_cpu() to make sure we're reading the proper CPU's
MISC block addresses. However, that caused trouble with CPU hotplug due to
the _on_cpu() helper issuing an IPI while IRQs are disabled.
But we don't have to do that: the block addresses are the same on any CPU
so we can read them on any CPU. (What practically happens is, we read them
on the BSP and cache them, and for later reads, we service them from the
cache).
Suggested-by: Yazen Ghannam <Yazen.Ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
... into a global, two-dimensional array and service subsequent reads from
that cache to avoid rdmsr_on_cpu() calls during CPU hotplug (IPIs with IRQs
disabled).
In addition, this fixes a KASAN slab-out-of-bounds read due to wrong usage
of the bank->blocks pointer.
Fixes: 27bd595027 ("x86/mce/AMD: Get address from already initialized block")
Reported-by: Johannes Hirte <johannes.hirte@datenkhaos.de>
Tested-by: Johannes Hirte <johannes.hirte@datenkhaos.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Link: http://lkml.kernel.org/r/20180414004230.GA2033@probook
mba_sc is a feedback loop where we periodically read MBM counters and
try to restrict the bandwidth below a max value so the below is always
true:
"current bandwidth(cur_bw) < user specified bandwidth(user_bw)"
The frequency of these checks is currently 1s and we just tag along the
MBM overflow timer to do the updates. Doing it once in a second also
makes the calculation of bandwidth easy. The steps of increase or
decrease of bandwidth is the minimum granularity specified by the
hardware.
Although the MBA's goal is to restrict the bandwidth below a maximum,
there may be a need to even increase the bandwidth. Since MBA controls
the L2 external bandwidth where as MBM measures the L3 external
bandwidth, we may end up restricting some rdtgroups unnecessarily. This
may happen in the sequence where rdtgroup (set of jobs) had high
"L3 <-> memory traffic" in initial phases -> mba_sc kicks in and reduced
bandwidth percentage values -> but after some it has mostly "L2 <-> L3"
traffic. In this scenario mba_sc increases the bandwidth percentage when
there is lesser memory traffic.
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/1524263781-14267-7-git-send-email-vikas.shivappa@linux.intel.com
When MBA software controller is enabled, a per domain storage is required
for user specified bandwidth in "MBps" and the "percentage" values which
are programmed into the IA32_MBA_THRTL_MSR. Add support for these data
structures and initialization.
The MBA percentage values have a default max value of 100 but however the
max value in MBps is not available from the hardware so it's set to
U32_MAX.
This simply says that the control group can use all bandwidth by default
but does not say what is the actual max bandwidth available. The actual
bandwidth that is available may depend on lot of factors like QPI link,
number of memory channels, memory channel frequency, its width and memory
speed, how many channels are configured and also if memory interleaving is
enabled. So there is no way to determine the maximum at runtime reliably.
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/1524263781-14267-4-git-send-email-vikas.shivappa@linux.intel.com
This kernel parameter allows to force kernel to use 4-level paging even
if hardware and kernel support 5-level paging.
The option may be useful to work around regressions related to 5-level
paging.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180518103528.59260-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The "336996 Speculative Execution Side Channel Mitigations" from
May defines this as SSB_NO, hence lets sync-up.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Expose the new virtualized architectural mechanism, VIRT_SSBD, for using
speculative store bypass disable (SSBD) under SVM. This will allow guests
to use SSBD on hardware that uses non-architectural mechanisms for enabling
SSBD.
[ tglx: Folded the migration fixup from Paolo Bonzini ]
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add the necessary logic for supporting the emulated VIRT_SPEC_CTRL MSR to
x86_virt_spec_ctrl(). If either X86_FEATURE_LS_CFG_SSBD or
X86_FEATURE_VIRT_SPEC_CTRL is set then use the new guest_virt_spec_ctrl
argument to check whether the state must be modified on the host. The
update reuses speculative_store_bypass_update() so the ZEN-specific sibling
coordination can be reused.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
x86_spec_ctrL_mask is intended to mask out bits from a MSR_SPEC_CTRL value
which are not to be modified. However the implementation is not really used
and the bitmask was inverted to make a check easier, which was removed in
"x86/bugs: Remove x86_spec_ctrl_set()"
Aside of that it is missing the STIBP bit if it is supported by the
platform, so if the mask would be used in x86_virt_spec_ctrl() then it
would prevent a guest from setting STIBP.
Add the STIBP bit if supported and use the mask in x86_virt_spec_ctrl() to
sanitize the value which is supplied by the guest.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
x86_spec_ctrl_set() is only used in bugs.c and the extra mask checks there
provide no real value as both call sites can just write x86_spec_ctrl_base
to MSR_SPEC_CTRL. x86_spec_ctrl_base is valid and does not need any extra
masking or checking.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
x86_spec_ctrl_base is the system wide default value for the SPEC_CTRL MSR.
x86_spec_ctrl_get_default() returns x86_spec_ctrl_base and was intended to
prevent modification to that variable. Though the variable is read only
after init and globaly visible already.
Remove the function and export the variable instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Function bodies are very similar and are going to grow more almost
identical code. Add a bool arg to determine whether SPEC_CTRL is being set
for the guest or restored to the host.
No functional changes.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The upcoming support for the virtual SPEC_CTRL MSR on AMD needs to reuse
speculative_store_bypass_update() to avoid code duplication. Add an
argument for supplying a thread info (TIF) value and create a wrapper
speculative_store_bypass_update_current() which is used at the existing
call site.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Some AMD processors only support a non-architectural means of enabling
speculative store bypass disable (SSBD). To allow a simplified view of
this to a guest, an architectural definition has been created through a new
CPUID bit, 0x80000008_EBX[25], and a new MSR, 0xc001011f. With this, a
hypervisor can virtualize the existence of this definition and provide an
architectural method for using SSBD to a guest.
Add the new CPUID feature, the new MSR and update the existing SSBD
support to use this MSR when present.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
AMD is proposing a VIRT_SPEC_CTRL MSR to handle the Speculative Store
Bypass Disable via MSR_AMD64_LS_CFG so that guests do not have to care
about the bit position of the SSBD bit and thus facilitate migration.
Also, the sibling coordination on Family 17H CPUs can only be done on
the host.
Extend x86_spec_ctrl_set_guest() and x86_spec_ctrl_restore_host() with an
extra argument for the VIRT_SPEC_CTRL MSR.
Hand in 0 from VMX and in SVM add a new virt_spec_ctrl member to the CPU
data structure which is going to be used in later patches for the actual
implementation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Add a ZEN feature bit so family-dependent static_cpu_has() optimizations
can be built for ZEN.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The SSBD enumeration is similarly to the other bits magically shared
between Intel and AMD though the mechanisms are different.
Make X86_FEATURE_SSBD synthetic and set it depending on the vendor specific
features or family dependent setup.
Change the Intel bit to X86_FEATURE_SPEC_CTRL_SSBD to denote that SSBD is
controlled via MSR_SPEC_CTRL and fix up the usage sites.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The availability of the SPEC_CTRL MSR is enumerated by a CPUID bit on
Intel and implied by IBRS or STIBP support on AMD. That's just confusing
and in case an AMD CPU has IBRS not supported because the underlying
problem has been fixed but has another bit valid in the SPEC_CTRL MSR,
the thing falls apart.
Add a synthetic feature bit X86_FEATURE_MSR_SPEC_CTRL to denote the
availability on both Intel and AMD.
While at it replace the boot_cpu_has() checks with static_cpu_has() where
possible. This prevents late microcode loading from exposing SPEC_CTRL, but
late loading is already very limited as it does not reevaluate the
mitigation options and other bits and pieces. Having static_cpu_has() is
the simplest and least fragile solution.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Intel and AMD have different CPUID bits hence for those use synthetic bits
which get set on the respective vendor's in init_speculation_control(). So
that debacles like what the commit message of
c65732e4f7 ("x86/cpu: Restore CPUID_8000_0008_EBX reload")
talks about don't happen anymore.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Jörg Otte <jrg.otte@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20180504161815.GG9257@pd.tnic
Kbuild uses the first file as the name for KBUILD_MODNAME.
mtrr uses main.c as its first file, so rename that file to mtrr.c
and fixup the Makefile.
Remove the now duplicate "mtrr: " prefixes from the logging calls.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/ae1fa81a0d1fad87571967b91ea90f70f486e853.1525964384.git.joe@perches.com
No point in exposing all these functions globaly as they are strict local
to the cpu management code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Fixes: 7bb4d366c ("x86/bugs: Make cpu_show_common() static")
Fixes: 24f7fc83b ("x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigation")
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
cpu_show_common() is not used outside of arch/x86/kernel/cpu/bugs.c, so
make it static.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
__ssb_select_mitigation() returns one of the members of enum ssb_mitigation,
not ssb_mitigation_cmd; fix the prototype to reflect that.
Fixes: 24f7fc83b9 ("x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigation")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Intel collateral will reference the SSB mitigation bit in IA32_SPEC_CTL[2]
as SSBD (Speculative Store Bypass Disable).
Hence changing it.
It is unclear yet what the MSR_IA32_ARCH_CAPABILITIES (0x10a) Bit(4) name
is going to be. Following the rename it would be SSBD_NO but that rolls out
to Speculative Store Bypass Disable No.
Also fixed the missing space in X86_FEATURE_AMD_SSBD.
[ tglx: Fixup x86_amd_rds_enable() and rds_tif_to_amd_ls_cfg() as well ]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Derive topology information from Extended Topology Enumeration (CPUID
function 0xB) when the information is available.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1524865681-112110-3-git-send-email-suravee.suthikulpanit@amd.com
Current implementation does not communicate whether it can successfully
detect CPUID function 0xB information. Therefore, modify the function to
return success or error codes. This will be used by subsequent patches.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1524865681-112110-2-git-send-email-suravee.suthikulpanit@amd.com
Last Level Cache ID can be calculated from the number of threads sharing
the cache, which is available from CPUID Fn0x8000001D (Cache Properties).
This is used to left-shift the APIC ID to derive LLC ID.
Therefore, default to this method unless the APIC ID enumeration does not
follow the scheme.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1524864877-111962-5-git-send-email-suravee.suthikulpanit@amd.com
Since this file contains general cache-related information for x86,
rename the file to a more generic name.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1524864877-111962-4-git-send-email-suravee.suthikulpanit@amd.com
Move smp_num_siblings and cpu_llc_id to cpu/common.c so that they're
always present as symbols and not only in the CONFIG_SMP case. Then,
other code using them doesn't need ugly ifdeffery anymore. Get rid of
some ifdeffery.
Signed-off-by: Borislav Petkov <bpetkov@suse.de>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1524864877-111962-2-git-send-email-suravee.suthikulpanit@amd.com
Each of the strings that we want to put into the buf[MAX_FLAG_OPT_SIZE]
in flags_read() is two characters long. But the sprintf() adds
a trailing newline and will add a terminating NUL byte. So
MAX_FLAG_OPT_SIZE needs to be 4.
sprintf() calls vsnprintf() and *that* does return:
" * The return value is the number of characters which would
* be generated for the given input, excluding the trailing
* '\0', as per ISO C99."
Note the "excluding".
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20180427163707.ktaiysvbk3yhk4wm@agluck-desk
