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commit 77245f1c3c6495521f6a3af082696ee2f8ce3921 upstream.
Under certain circumstances, an integer division by 0 which faults, can
leave stale quotient data from a previous division operation on Zen1
microarchitectures.
Do a dummy division 0/1 before returning from the #DE exception handler
in order to avoid any leaks of potentially sensitive data.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Upstream commit: d893832d0e1ef41c72cdae444268c1d64a2be8ad
Add the option to flush IBPB only on VMEXIT in order to protect from
malicious guests but one otherwise trusts the software that runs on the
hypervisor.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Upstream commit: 1b5277c0ea0b247393a9c426769fde18cff5e2f6
Add support for the CPUID flag which denotes that the CPU is not
affected by SRSO.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Upstream commit: 79113e4060aba744787a81edb9014f2865193854
Add support for the synthetic CPUID flag which "if this bit is 1,
it indicates that MSR 49h (PRED_CMD) bit 0 (IBPB) flushes all branch
type predictions from the CPU branch predictor."
This flag is there so that this capability in guests can be detected
easily (otherwise one would have to track microcode revisions which is
impossible for guests).
It is also needed only for Zen3 and -4. The other two (Zen1 and -2)
always flush branch type predictions by default.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Upstream commit: fb3bd914b3ec28f5fb697ac55c4846ac2d542855
Add a mitigation for the speculative return address stack overflow
vulnerability found on AMD processors.
The mitigation works by ensuring all RET instructions speculate to
a controlled location, similar to how speculation is controlled in the
retpoline sequence. To accomplish this, the __x86_return_thunk forces
the CPU to mispredict every function return using a 'safe return'
sequence.
To ensure the safety of this mitigation, the kernel must ensure that the
safe return sequence is itself free from attacker interference. In Zen3
and Zen4, this is accomplished by creating a BTB alias between the
untraining function srso_untrain_ret_alias() and the safe return
function srso_safe_ret_alias() which results in evicting a potentially
poisoned BTB entry and using that safe one for all function returns.
In older Zen1 and Zen2, this is accomplished using a reinterpretation
technique similar to Retbleed one: srso_untrain_ret() and
srso_safe_ret().
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 8415a74852d7c24795007ee9862d25feb519007c upstream.
Add support for CPUID leaf 80000021, EAX. The majority of the features will be
used in the kernel and thus a separate leaf is appropriate.
Include KVM's reverse_cpuid entry because features are used by VM guests, too.
[ bp: Massage commit message. ]
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20230124163319.2277355-2-kim.phillips@amd.com
[bwh: Backported to 6.1: adjust context]
Signed-off-by: Ben Hutchings <benh@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Upstream commit: 0e52740ffd10c6c316837c6c128f460f1aaba1ea
There was never a doubt in my mind that they would not fit into a single
u32 eventually.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 8974eb588283b7d44a7c91fa09fcbaf380339f3a upstream
Gather Data Sampling (GDS) is a hardware vulnerability which allows
unprivileged speculative access to data which was previously stored in
vector registers.
Intel processors that support AVX2 and AVX512 have gather instructions
that fetch non-contiguous data elements from memory. On vulnerable
hardware, when a gather instruction is transiently executed and
encounters a fault, stale data from architectural or internal vector
registers may get transiently stored to the destination vector
register allowing an attacker to infer the stale data using typical
side channel techniques like cache timing attacks.
This mitigation is different from many earlier ones for two reasons.
First, it is enabled by default and a bit must be set to *DISABLE* it.
This is the opposite of normal mitigation polarity. This means GDS can
be mitigated simply by updating microcode and leaving the new control
bit alone.
Second, GDS has a "lock" bit. This lock bit is there because the
mitigation affects the hardware security features KeyLocker and SGX.
It needs to be enabled and *STAY* enabled for these features to be
mitigated against GDS.
The mitigation is enabled in the microcode by default. Disable it by
setting gather_data_sampling=off or by disabling all mitigations with
mitigations=off. The mitigation status can be checked by reading:
/sys/devices/system/cpu/vulnerabilities/gather_data_sampling
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit be8de49bea505e7777a69ef63d60e02ac1712683 upstream.
Certain AMD processors are vulnerable to a cross-thread return address
predictions bug. When running in SMT mode and one of the sibling threads
transitions out of C0 state, the other sibling thread could use return
target predictions from the sibling thread that transitioned out of C0.
The Spectre v2 mitigations cover the Linux kernel, as it fills the RSB
when context switching to the idle thread. However, KVM allows a VMM to
prevent exiting guest mode when transitioning out of C0. A guest could
act maliciously in this situation, so create a new x86 BUG that can be
used to detect if the processor is vulnerable.
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <91cec885656ca1fcd4f0185ce403a53dd9edecb7.1675956146.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Support for the TSX control MSR is enumerated in MSR_IA32_ARCH_CAPABILITIES.
This is different from how other CPU features are enumerated i.e. via
CPUID. Currently, a call to tsx_ctrl_is_supported() is required for
enumerating the feature. In the absence of a feature bit for TSX control,
any code that relies on checking feature bits directly will not work.
In preparation for adding a feature bit check in MSR save/restore
during suspend/resume, set a new feature bit X86_FEATURE_TSX_CTRL when
MSR_IA32_TSX_CTRL is present. Also make tsx_ctrl_is_supported() use the
new feature bit to avoid any overhead of reading the MSR.
[ bp: Remove tsx_ctrl_is_supported(), add room for two more feature
bits in word 11 which are coming up in the next merge window. ]
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/de619764e1d98afbb7a5fa58424f1278ede37b45.1668539735.git.pawan.kumar.gupta@linux.intel.com
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Merge upstream to get RAPTORLAKE_S
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
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CPUID leaf 0x80000022 i.e. ExtPerfMonAndDbg advertises some new performance
monitoring features for AMD processors.
Bit 1 of EAX indicates support for Last Branch Record Extension Version 2
(LbrExtV2) features. If found to be set during PMU initialization, the EBX
bits of the same leaf can be used to determine the number of available LBR
entries.
For better utilization of feature words, LbrExtV2 is added as a scattered
feature bit.
[peterz: Rename to AMD_LBR_V2]
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/172d2b0df39306ed77221c45ee1aa62e8ae0548d.1660211399.git.sandipan.das@amd.com
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Older Intel CPUs that are not in the affected processor list for MMIO
Stale Data vulnerabilities currently report "Not affected" in sysfs,
which may not be correct. Vulnerability status for these older CPUs is
unknown.
Add known-not-affected CPUs to the whitelist. Report "unknown"
mitigation status for CPUs that are not in blacklist, whitelist and also
don't enumerate MSR ARCH_CAPABILITIES bits that reflect hardware
immunity to MMIO Stale Data vulnerabilities.
Mitigation is not deployed when the status is unknown.
[ bp: Massage, fixup. ]
Fixes: 8d50cdf8b834 ("x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale Data")
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Suggested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/a932c154772f2121794a5f2eded1a11013114711.1657846269.git.pawan.kumar.gupta@linux.intel.com
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 eIBRS fixes from Borislav Petkov:
"More from the CPU vulnerability nightmares front:
Intel eIBRS machines do not sufficiently mitigate against RET
mispredictions when doing a VM Exit therefore an additional RSB,
one-entry stuffing is needed"
* tag 'x86_bugs_pbrsb' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Add LFENCE to RSB fill sequence
x86/speculation: Add RSB VM Exit protections
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Pull kvm updates from Paolo Bonzini:
"Quite a large pull request due to a selftest API overhaul and some
patches that had come in too late for 5.19.
ARM:
- Unwinder implementations for both nVHE modes (classic and
protected), complete with an overflow stack
- Rework of the sysreg access from userspace, with a complete rewrite
of the vgic-v3 view to allign with the rest of the infrastructure
- Disagregation of the vcpu flags in separate sets to better track
their use model.
- A fix for the GICv2-on-v3 selftest
- A small set of cosmetic fixes
RISC-V:
- Track ISA extensions used by Guest using bitmap
- Added system instruction emulation framework
- Added CSR emulation framework
- Added gfp_custom flag in struct kvm_mmu_memory_cache
- Added G-stage ioremap() and iounmap() functions
- Added support for Svpbmt inside Guest
s390:
- add an interface to provide a hypervisor dump for secure guests
- improve selftests to use TAP interface
- enable interpretive execution of zPCI instructions (for PCI
passthrough)
- First part of deferred teardown
- CPU Topology
- PV attestation
- Minor fixes
x86:
- Permit guests to ignore single-bit ECC errors
- Intel IPI virtualization
- Allow getting/setting pending triple fault with
KVM_GET/SET_VCPU_EVENTS
- PEBS virtualization
- Simplify PMU emulation by just using PERF_TYPE_RAW events
- More accurate event reinjection on SVM (avoid retrying
instructions)
- Allow getting/setting the state of the speaker port data bit
- Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls
are inconsistent
- "Notify" VM exit (detect microarchitectural hangs) for Intel
- Use try_cmpxchg64 instead of cmpxchg64
- Ignore benign host accesses to PMU MSRs when PMU is disabled
- Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior
- Allow NX huge page mitigation to be disabled on a per-vm basis
- Port eager page splitting to shadow MMU as well
- Enable CMCI capability by default and handle injected UCNA errors
- Expose pid of vcpu threads in debugfs
- x2AVIC support for AMD
- cleanup PIO emulation
- Fixes for LLDT/LTR emulation
- Don't require refcounted "struct page" to create huge SPTEs
- Miscellaneous cleanups:
- MCE MSR emulation
- Use separate namespaces for guest PTEs and shadow PTEs bitmasks
- PIO emulation
- Reorganize rmap API, mostly around rmap destruction
- Do not workaround very old KVM bugs for L0 that runs with nesting enabled
- new selftests API for CPUID
Generic:
- Fix races in gfn->pfn cache refresh; do not pin pages tracked by
the cache
- new selftests API using struct kvm_vcpu instead of a (vm, id)
tuple"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (606 commits)
selftests: kvm: set rax before vmcall
selftests: KVM: Add exponent check for boolean stats
selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test
selftests: KVM: Check stat name before other fields
KVM: x86/mmu: remove unused variable
RISC-V: KVM: Add support for Svpbmt inside Guest/VM
RISC-V: KVM: Use PAGE_KERNEL_IO in kvm_riscv_gstage_ioremap()
RISC-V: KVM: Add G-stage ioremap() and iounmap() functions
KVM: Add gfp_custom flag in struct kvm_mmu_memory_cache
RISC-V: KVM: Add extensible CSR emulation framework
RISC-V: KVM: Add extensible system instruction emulation framework
RISC-V: KVM: Factor-out instruction emulation into separate sources
RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run
RISC-V: KVM: Make kvm_riscv_guest_timer_init a void function
RISC-V: KVM: Fix variable spelling mistake
RISC-V: KVM: Improve ISA extension by using a bitmap
KVM, x86/mmu: Fix the comment around kvm_tdp_mmu_zap_leafs()
KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog
KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT
KVM: x86: Do not block APIC write for non ICR registers
...
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tl;dr: The Enhanced IBRS mitigation for Spectre v2 does not work as
documented for RET instructions after VM exits. Mitigate it with a new
one-entry RSB stuffing mechanism and a new LFENCE.
== Background ==
Indirect Branch Restricted Speculation (IBRS) was designed to help
mitigate Branch Target Injection and Speculative Store Bypass, i.e.
Spectre, attacks. IBRS prevents software run in less privileged modes
from affecting branch prediction in more privileged modes. IBRS requires
the MSR to be written on every privilege level change.
To overcome some of the performance issues of IBRS, Enhanced IBRS was
introduced. eIBRS is an "always on" IBRS, in other words, just turn
it on once instead of writing the MSR on every privilege level change.
When eIBRS is enabled, more privileged modes should be protected from
less privileged modes, including protecting VMMs from guests.
== Problem ==
Here's a simplification of how guests are run on Linux' KVM:
void run_kvm_guest(void)
{
// Prepare to run guest
VMRESUME();
// Clean up after guest runs
}
The execution flow for that would look something like this to the
processor:
1. Host-side: call run_kvm_guest()
2. Host-side: VMRESUME
3. Guest runs, does "CALL guest_function"
4. VM exit, host runs again
5. Host might make some "cleanup" function calls
6. Host-side: RET from run_kvm_guest()
Now, when back on the host, there are a couple of possible scenarios of
post-guest activity the host needs to do before executing host code:
* on pre-eIBRS hardware (legacy IBRS, or nothing at all), the RSB is not
touched and Linux has to do a 32-entry stuffing.
* on eIBRS hardware, VM exit with IBRS enabled, or restoring the host
IBRS=1 shortly after VM exit, has a documented side effect of flushing
the RSB except in this PBRSB situation where the software needs to stuff
the last RSB entry "by hand".
IOW, with eIBRS supported, host RET instructions should no longer be
influenced by guest behavior after the host retires a single CALL
instruction.
However, if the RET instructions are "unbalanced" with CALLs after a VM
exit as is the RET in #6, it might speculatively use the address for the
instruction after the CALL in #3 as an RSB prediction. This is a problem
since the (untrusted) guest controls this address.
Balanced CALL/RET instruction pairs such as in step #5 are not affected.
== Solution ==
The PBRSB issue affects a wide variety of Intel processors which
support eIBRS. But not all of them need mitigation. Today,
X86_FEATURE_RSB_VMEXIT triggers an RSB filling sequence that mitigates
PBRSB. Systems setting RSB_VMEXIT need no further mitigation - i.e.,
eIBRS systems which enable legacy IBRS explicitly.
However, such systems (X86_FEATURE_IBRS_ENHANCED) do not set RSB_VMEXIT
and most of them need a new mitigation.
Therefore, introduce a new feature flag X86_FEATURE_RSB_VMEXIT_LITE
which triggers a lighter-weight PBRSB mitigation versus RSB_VMEXIT.
The lighter-weight mitigation performs a CALL instruction which is
immediately followed by a speculative execution barrier (INT3). This
steers speculative execution to the barrier -- just like a retpoline
-- which ensures that speculation can never reach an unbalanced RET.
Then, ensure this CALL is retired before continuing execution with an
LFENCE.
In other words, the window of exposure is opened at VM exit where RET
behavior is troublesome. While the window is open, force RSB predictions
sampling for RET targets to a dead end at the INT3. Close the window
with the LFENCE.
There is a subset of eIBRS systems which are not vulnerable to PBRSB.
Add these systems to the cpu_vuln_whitelist[] as NO_EIBRS_PBRSB.
Future systems that aren't vulnerable will set ARCH_CAP_PBRSB_NO.
[ bp: Massage, incorporate review comments from Andy Cooper. ]
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Co-developed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu updates from Borislav Petkov:
- Remove the vendor check when selecting MWAIT as the default idle
state
- Respect idle=nomwait when supplied on the kernel cmdline
- Two small cleanups
* tag 'x86_cpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Use MSR_IA32_MISC_ENABLE constants
x86: Fix comment for X86_FEATURE_ZEN
x86: Remove vendor checks from prefer_mwait_c1_over_halt
x86: Handle idle=nomwait cmdline properly for x86_idle
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KVM/s390, KVM/x86 and common infrastructure changes for 5.20
x86:
* Permit guests to ignore single-bit ECC errors
* Fix races in gfn->pfn cache refresh; do not pin pages tracked by the cache
* Intel IPI virtualization
* Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS
* PEBS virtualization
* Simplify PMU emulation by just using PERF_TYPE_RAW events
* More accurate event reinjection on SVM (avoid retrying instructions)
* Allow getting/setting the state of the speaker port data bit
* Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent
* "Notify" VM exit (detect microarchitectural hangs) for Intel
* Cleanups for MCE MSR emulation
s390:
* add an interface to provide a hypervisor dump for secure guests
* improve selftests to use TAP interface
* enable interpretive execution of zPCI instructions (for PCI passthrough)
* First part of deferred teardown
* CPU Topology
* PV attestation
* Minor fixes
Generic:
* new selftests API using struct kvm_vcpu instead of a (vm, id) tuple
x86:
* Use try_cmpxchg64 instead of cmpxchg64
* Bugfixes
* Ignore benign host accesses to PMU MSRs when PMU is disabled
* Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior
* x86/MMU: Allow NX huge pages to be disabled on a per-vm basis
* Port eager page splitting to shadow MMU as well
* Enable CMCI capability by default and handle injected UCNA errors
* Expose pid of vcpu threads in debugfs
* x2AVIC support for AMD
* cleanup PIO emulation
* Fixes for LLDT/LTR emulation
* Don't require refcounted "struct page" to create huge SPTEs
x86 cleanups:
* Use separate namespaces for guest PTEs and shadow PTEs bitmasks
* PIO emulation
* Reorganize rmap API, mostly around rmap destruction
* Do not workaround very old KVM bugs for L0 that runs with nesting enabled
* new selftests API for CPUID
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On AMD IBRS does not prevent Retbleed; as such use IBPB before a
firmware call to flush the branch history state.
And because in order to do an EFI call, the kernel maps a whole lot of
the kernel page table into the EFI page table, do an IBPB just in case
in order to prevent the scenario of poisoning the BTB and causing an EFI
call using the unprotected RET there.
[ bp: Massage. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220715194550.793957-1-cascardo@canonical.com
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Some Intel processors may use alternate predictors for RETs on
RSB-underflow. This condition may be vulnerable to Branch History
Injection (BHI) and intramode-BTI.
Kernel earlier added spectre_v2 mitigation modes (eIBRS+Retpolines,
eIBRS+LFENCE, Retpolines) which protect indirect CALLs and JMPs against
such attacks. However, on RSB-underflow, RET target prediction may
fallback to alternate predictors. As a result, RET's predicted target
may get influenced by branch history.
A new MSR_IA32_SPEC_CTRL bit (RRSBA_DIS_S) controls this fallback
behavior when in kernel mode. When set, RETs will not take predictions
from alternate predictors, hence mitigating RETs as well. Support for
this is enumerated by CPUID.7.2.EDX[RRSBA_CTRL] (bit2).
For spectre v2 mitigation, when a user selects a mitigation that
protects indirect CALLs and JMPs against BHI and intramode-BTI, set
RRSBA_DIS_S also to protect RETs for RSB-underflow case.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
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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>
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Prevent RSB underflow/poisoning attacks with RSB. While at it, add a
bunch of comments to attempt to document the current state of tribal
knowledge about RSB attacks and what exactly is being mitigated.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
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jmp2ret mitigates the easy-to-attack case at relatively low overhead.
It mitigates the long speculation windows after a mispredicted RET, but
it does not mitigate the short speculation window from arbitrary
instruction boundaries.
On Zen2, there is a chicken bit which needs setting, which mitigates
"arbitrary instruction boundaries" down to just "basic block boundaries".
But there is no fix for the short speculation window on basic block
boundaries, other than to flush the entire BTB to evict all attacker
predictions.
On the spectrum of "fast & blurry" -> "safe", there is (on top of STIBP
or no-SMT):
1) Nothing System wide open
2) jmp2ret May stop a script kiddy
3) jmp2ret+chickenbit Raises the bar rather further
4) IBPB Only thing which can count as "safe".
Tentative numbers put IBPB-on-entry at a 2.5x hit on Zen2, and a 10x hit
on Zen1 according to lmbench.
[ bp: Fixup feature bit comments, document option, 32-bit build fix. ]
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>
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Implement Kernel IBRS - currently the only known option to mitigate RSB
underflow speculation issues on Skylake hardware.
Note: since IBRS_ENTER requires fuller context established than
UNTRAIN_RET, it must be placed after it. However, since UNTRAIN_RET
itself implies a RET, it must come after IBRS_ENTER. This means
IBRS_ENTER needs to also move UNTRAIN_RET.
Note 2: KERNEL_IBRS is sub-optimal for XenPV.
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>
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Report that AMD x86 CPUs are vulnerable to the RETBleed (Arbitrary
Speculative Code Execution with Return Instructions) attack.
[peterz: add hygon]
[kim: invert parity; fam15h]
Co-developed-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.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>
|
|
Note: needs to be in a section distinct from Retpolines such that the
Retpoline RET substitution cannot possibly use immediate jumps.
ORC unwinding for zen_untrain_ret() and __x86_return_thunk() is a
little tricky but works due to the fact that zen_untrain_ret() doesn't
have any stack ops and as such will emit a single ORC entry at the
start (+0x3f).
Meanwhile, unwinding an IP, including the __x86_return_thunk() one
(+0x40) will search for the largest ORC entry smaller or equal to the
IP, these will find the one ORC entry (+0x3f) and all works.
[ Alexandre: SVM part. ]
[ bp: Build fix, massages. ]
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>
|
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Introduce X86_FEATURE_RETHUNK for those afflicted with needing this.
[ bp: Do only INT3 padding - simpler. ]
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>
|
|
In order to extend the RETPOLINE features to 4, move them to word 11
where there is still room. This mostly keeps DISABLE_RETPOLINE
simple.
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>
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Introduce a new feature bit for virtualized x2APIC (x2AVIC) in
CPUID_Fn8000000A_EDX [SVM Revision and Feature Identification].
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220519102709.24125-2-suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 MMIO stale data fixes from Thomas Gleixner:
"Yet another hw vulnerability with a software mitigation: Processor
MMIO Stale Data.
They are a class of MMIO-related weaknesses which can expose stale
data by propagating it into core fill buffers. Data which can then be
leaked using the usual speculative execution methods.
Mitigations include this set along with microcode updates and are
similar to MDS and TAA vulnerabilities: VERW now clears those buffers
too"
* tag 'x86-bugs-2022-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation/mmio: Print SMT warning
KVM: x86/speculation: Disable Fill buffer clear within guests
x86/speculation/mmio: Reuse SRBDS mitigation for SBDS
x86/speculation/srbds: Update SRBDS mitigation selection
x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale Data
x86/speculation/mmio: Enable CPU Fill buffer clearing on idle
x86/bugs: Group MDS, TAA & Processor MMIO Stale Data mitigations
x86/speculation/mmio: Add mitigation for Processor MMIO Stale Data
x86/speculation: Add a common function for MD_CLEAR mitigation update
x86/speculation/mmio: Enumerate Processor MMIO Stale Data bug
Documentation: Add documentation for Processor MMIO Stale Data
|
|
The feature X86_FEATURE_ZEN implies that the CPU based on Zen
microarchitecture. Call this out explicitly in the comment.
Signed-off-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lkml.kernel.org/r/9931b01a85120a0d1faf0f244e8de3f2190e774c.1654538381.git-series.wyes.karny@amd.com
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Pull kvm updates from Paolo Bonzini:
"S390:
- ultravisor communication device driver
- fix TEID on terminating storage key ops
RISC-V:
- Added Sv57x4 support for G-stage page table
- Added range based local HFENCE functions
- Added remote HFENCE functions based on VCPU requests
- Added ISA extension registers in ONE_REG interface
- Updated KVM RISC-V maintainers entry to cover selftests support
ARM:
- Add support for the ARMv8.6 WFxT extension
- Guard pages for the EL2 stacks
- Trap and emulate AArch32 ID registers to hide unsupported features
- Ability to select and save/restore the set of hypercalls exposed to
the guest
- Support for PSCI-initiated suspend in collaboration with userspace
- GICv3 register-based LPI invalidation support
- Move host PMU event merging into the vcpu data structure
- GICv3 ITS save/restore fixes
- The usual set of small-scale cleanups and fixes
x86:
- New ioctls to get/set TSC frequency for a whole VM
- Allow userspace to opt out of hypercall patching
- Only do MSR filtering for MSRs accessed by rdmsr/wrmsr
AMD SEV improvements:
- Add KVM_EXIT_SHUTDOWN metadata for SEV-ES
- V_TSC_AUX support
Nested virtualization improvements for AMD:
- Support for "nested nested" optimizations (nested vVMLOAD/VMSAVE,
nested vGIF)
- Allow AVIC to co-exist with a nested guest running
- Fixes for LBR virtualizations when a nested guest is running, and
nested LBR virtualization support
- PAUSE filtering for nested hypervisors
Guest support:
- Decoupling of vcpu_is_preempted from PV spinlocks"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (199 commits)
KVM: x86: Fix the intel_pt PMI handling wrongly considered from guest
KVM: selftests: x86: Sync the new name of the test case to .gitignore
Documentation: kvm: reorder ARM-specific section about KVM_SYSTEM_EVENT_SUSPEND
x86, kvm: use correct GFP flags for preemption disabled
KVM: LAPIC: Drop pending LAPIC timer injection when canceling the timer
x86/kvm: Alloc dummy async #PF token outside of raw spinlock
KVM: x86: avoid calling x86 emulator without a decoded instruction
KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak
x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave)
s390/uv_uapi: depend on CONFIG_S390
KVM: selftests: x86: Fix test failure on arch lbr capable platforms
KVM: LAPIC: Trace LAPIC timer expiration on every vmentry
KVM: s390: selftest: Test suppression indication on key prot exception
KVM: s390: Don't indicate suppression on dirtying, failing memop
selftests: drivers/s390x: Add uvdevice tests
drivers/s390/char: Add Ultravisor io device
MAINTAINERS: Update KVM RISC-V entry to cover selftests support
RISC-V: KVM: Introduce ISA extension register
RISC-V: KVM: Cleanup stale TLB entries when host CPU changes
RISC-V: KVM: Add remote HFENCE functions based on VCPU requests
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events updates from Ingo Molnar:
"Platform PMU changes:
- x86/intel:
- Add new Intel Alder Lake and Raptor Lake support
- x86/amd:
- AMD Zen4 IBS extensions support
- Add AMD PerfMonV2 support
- Add AMD Fam19h Branch Sampling support
Generic changes:
- signal: Deliver SIGTRAP on perf event asynchronously if blocked
Perf instrumentation can be driven via SIGTRAP, but this causes a
problem when SIGTRAP is blocked by a task & terminate the task.
Allow user-space to request these signals asynchronously (after
they get unblocked) & also give the information to the signal
handler when this happens:
"To give user space the ability to clearly distinguish
synchronous from asynchronous signals, introduce
siginfo_t::si_perf_flags and TRAP_PERF_FLAG_ASYNC (opted for
flags in case more binary information is required in future).
The resolution to the problem is then to (a) no longer force the
signal (avoiding the terminations), but (b) tell user space via
si_perf_flags if the signal was synchronous or not, so that such
signals can be handled differently (e.g. let user space decide
to ignore or consider the data imprecise). "
- Unify/standardize the /sys/devices/cpu/events/* output format.
- Misc fixes & cleanups"
* tag 'perf-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
perf/x86/amd/core: Fix reloading events for SVM
perf/x86/amd: Run AMD BRS code only on supported hw
perf/x86/amd: Fix AMD BRS period adjustment
perf/x86/amd: Remove unused variable 'hwc'
perf/ibs: Fix comment
perf/amd/ibs: Advertise zen4_ibs_extensions as pmu capability attribute
perf/amd/ibs: Add support for L3 miss filtering
perf/amd/ibs: Use ->is_visible callback for dynamic attributes
perf/amd/ibs: Cascade pmu init functions' return value
perf/x86/uncore: Add new Alder Lake and Raptor Lake support
perf/x86/uncore: Clean up uncore_pci_ids[]
perf/x86/cstate: Add new Alder Lake and Raptor Lake support
perf/x86/msr: Add new Alder Lake and Raptor Lake support
perf/x86: Add new Alder Lake and Raptor Lake support
perf/amd/ibs: Use interrupt regs ip for stack unwinding
perf/x86/amd/core: Add PerfMonV2 overflow handling
perf/x86/amd/core: Add PerfMonV2 counter control
perf/x86/amd/core: Detect available counters
perf/x86/amd/core: Detect PerfMonV2 support
x86/msr: Add PerfCntrGlobal* registers
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fpu updates from Borislav Petkov:
- Add support for XSAVEC - the Compacted XSTATE saving variant - and
thus allow for guests to use this compacted XSTATE variant when the
hypervisor exports that support
- A variable shadowing cleanup
* tag 'x86_fpu_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu: Cleanup variable shadowing
x86/fpu/xsave: Support XSAVEC in the kernel
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Processor MMIO Stale Data is a class of vulnerabilities that may
expose data after an MMIO operation. For more details please refer to
Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst
Add the Processor MMIO Stale Data bug enumeration. A microcode update
adds new bits to the MSR IA32_ARCH_CAPABILITIES, define them.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
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CPUID leaf 0x80000022 i.e. ExtPerfMonAndDbg advertises some
new performance monitoring features for AMD processors.
Bit 0 of EAX indicates support for Performance Monitoring
Version 2 (PerfMonV2) features. If found to be set during
PMU initialization, the EBX bits of the same CPUID function
can be used to determine the number of available PMCs for
different PMU types. Additionally, Core PMCs can be managed
using new global control and status registers.
For better utilization of feature words, PerfMonV2 is added
as a scattered feature bit.
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/c70e497e22f18e7f05b025bb64ca21cc12b17792.1650515382.git.sandipan.das@amd.com
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The TSC_AUX virtualization feature allows AMD SEV-ES guests to securely use
TSC_AUX (auxiliary time stamp counter data) in the RDTSCP and RDPID
instructions. The TSC_AUX value is set using the WRMSR instruction to the
TSC_AUX MSR (0xC0000103). It is read by the RDMSR, RDTSCP and RDPID
instructions. If the read/write of the TSC_AUX MSR is intercepted, then
RDTSCP and RDPID must also be intercepted when TSC_AUX virtualization
is present. However, the RDPID instruction can't be intercepted. This means
that when TSC_AUX virtualization is present, RDTSCP and TSC_AUX MSR
read/write must not be intercepted for SEV-ES (or SEV-SNP) guests.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <165040164424.1399644.13833277687385156344.stgit@bmoger-ubuntu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The TSC_AUX Virtualization feature allows AMD SEV-ES guests to securely use
TSC_AUX (auxiliary time stamp counter data) MSR in RDTSCP and RDPID
instructions.
The TSC_AUX MSR is typically initialized to APIC ID or another unique
identifier so that software can quickly associate returned TSC value
with the logical processor.
Add the feature bit and also include it in the kvm for detection.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Acked-by: Borislav Petkov <bp@suse.de>
Message-Id: <165040157111.1399644.6123821125319995316.stgit@bmoger-ubuntu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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XSAVEC is the user space counterpart of XSAVES which cannot save supervisor
state. In virtualization scenarios the hypervisor does not expose XSAVES
but XSAVEC to the guest, though the kernel does not make use of it.
That's unfortunate because XSAVEC uses the compacted format of saving the
XSTATE. This is more efficient in terms of storage space vs. XSAVE[OPT] as
it does not create holes for XSTATE components which are not supported or
enabled by the kernel but are available in hardware. There is room for
further optimizations when XSAVEC/S and XGETBV1 are supported.
In order to support XSAVEC:
- Define the XSAVEC ASM macro as it's not yet supported by the required
minimal toolchain.
- Create a software defined X86_FEATURE_XCOMPACTED to select the compacted
XSTATE buffer format for both XSAVEC and XSAVES.
- Make XSAVEC an option in the 'XSAVE' ASM alternatives
Requested-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220404104820.598704095@linutronix.de
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In preparation of extending cc_platform_has() API to support TDX guest,
use CPUID instruction to detect support for TDX guests in the early
boot code (via tdx_early_init()). Since copy_bootdata() is the first
user of cc_platform_has() API, detect the TDX guest status before it.
Define a synthetic feature flag (X86_FEATURE_TDX_GUEST) and set this
bit in a valid TDX guest platform.
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20220405232939.73860-2-kirill.shutemov@linux.intel.com
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Add a cpu feature for AMD Fam19h Branch Sampling feature as bit
31 of EBX on CPUID leaf function 0x80000008.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220322221517.2510440-3-eranian@google.com
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 CET-IBT (Control-Flow-Integrity) support from Peter Zijlstra:
"Add support for Intel CET-IBT, available since Tigerlake (11th gen),
which is a coarse grained, hardware based, forward edge
Control-Flow-Integrity mechanism where any indirect CALL/JMP must
target an ENDBR instruction or suffer #CP.
Additionally, since Alderlake (12th gen)/Sapphire-Rapids, speculation
is limited to 2 instructions (and typically fewer) on branch targets
not starting with ENDBR. CET-IBT also limits speculation of the next
sequential instruction after the indirect CALL/JMP [1].
CET-IBT is fundamentally incompatible with retpolines, but provides,
as described above, speculation limits itself"
[1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html
* tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
kvm/emulate: Fix SETcc emulation for ENDBR
x86/Kconfig: Only allow CONFIG_X86_KERNEL_IBT with ld.lld >= 14.0.0
x86/Kconfig: Only enable CONFIG_CC_HAS_IBT for clang >= 14.0.0
kbuild: Fixup the IBT kbuild changes
x86/Kconfig: Do not allow CONFIG_X86_X32_ABI=y with llvm-objcopy
x86: Remove toolchain check for X32 ABI capability
x86/alternative: Use .ibt_endbr_seal to seal indirect calls
objtool: Find unused ENDBR instructions
objtool: Validate IBT assumptions
objtool: Add IBT/ENDBR decoding
objtool: Read the NOENDBR annotation
x86: Annotate idtentry_df()
x86,objtool: Move the ASM_REACHABLE annotation to objtool.h
x86: Annotate call_on_stack()
objtool: Rework ASM_REACHABLE
x86: Mark __invalid_creds() __noreturn
exit: Mark do_group_exit() __noreturn
x86: Mark stop_this_cpu() __noreturn
objtool: Ignore extra-symbol code
objtool: Rename --duplicate to --lto
...
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull thermal control updates from Rafael Wysocki:
"As far as new functionality is concerned, there is a new thermal
driver for the Intel Hardware Feedback Interface (HFI) along with some
intel-speed-select utility changes to support it. There are also new
DT compatible strings for a couple of platforms, and thermal zones on
some platforms will be registered as HWmon sensors now.
Apart from the above, some drivers are updated (fixes mostly) and
there is a new piece of documentation for the Intel DPTF (Dynamic
Power and Thermal Framework) sysfs interface.
Specifics:
- Add a new thermal driver for the Intel Hardware Feedback Interface
(HFI) including the HFI initialization, HFI notification interrupt
handling and sending CPU capabilities change messages to user space
via the thermal netlink interface (Ricardo Neri, Srinivas
Pandruvada, Nathan Chancellor, Randy Dunlap).
- Extend the intel-speed-select utility to handle out-of-band CPU
configuration changes and add support for the CPU capabilities
change messages sent over the thermal netlink interface by the new
HFI thermal driver to it (Srinivas Pandruvada).
- Convert the DT bindings to yaml format for the Exynos platform and
fix and update the MAINTAINERS file for this driver (Krzysztof
Kozlowski).
- Register the thermal zones as HWmon sensors for the QCom's Tsens
driver and TI thermal platforms (Dmitry Baryshkov, Romain Naour).
- Add the msm8953 compatible documentation in the bindings (Luca
Weiss).
- Add the sm8150 platform support to the QCom LMh driver's DT binding
(Thara Gopinath).
- Check the command result from the IPC command to the BPMP in the
Tegra driver (Mikko Perttunen).
- Silence the error for normal configuration where the interrupt is
optionnal in the Broadcom thermal driver (Florian Fainelli).
- Remove remaining dead code from the TI thermal driver (Yue
Haibing).
- Don't use bitmap_weight() in end_power_clamp() in the powerclamp
driver (Yury Norov).
- Update the OS policy capabilities handshake in the int340x thermal
driver (Srinivas Pandruvada).
- Increase the policies bitmap size in int340x (Srinivas Pandruvada).
- Replace acpi_bus_get_device() with acpi_fetch_acpi_dev() in the
int340x thermal driver (Rafael Wysocki).
- Check for NULL after calling kmemdup() in int340x (Jiasheng Jiang).
- Add Intel Dynamic Power and Thermal Framework (DPTF) kernel
interface documentation (Srinivas Pandruvada).
- Fix bullet list warning in the thermal documentation (Randy
Dunlap)"
* tag 'thermal-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (30 commits)
thermal: int340x: Update OS policy capability handshake
thermal: int340x: Increase bitmap size
Documentation: thermal: DPTF Documentation
MAINTAINERS: thermal: samsung: update Krzysztof Kozlowski's email
thermal/drivers/ti-soc-thermal: Remove unused function ti_thermal_get_temp()
thermal/drivers/brcmstb_thermal: Interrupt is optional
thermal: tegra-bpmp: Handle errors in BPMP response
drivers/thermal/ti-soc-thermal: Add hwmon support
dt-bindings: thermal: tsens: Add msm8953 compatible
dt-bindings: thermal: Add sm8150 compatible string for LMh
thermal/drivers/qcom/lmh: Add support for sm8150
thermal/drivers/tsens: register thermal zones as hwmon sensors
MAINTAINERS: thermal: samsung: Drop obsolete properties
dt-bindings: thermal: samsung: Convert to dtschema
tools/power/x86/intel-speed-select: v1.12 release
tools/power/x86/intel-speed-select: HFI support
tools/power/x86/intel-speed-select: OOB daemon mode
thermal: intel: hfi: INTEL_HFI_THERMAL depends on NET
thermal: netlink: Fix parameter type of thermal_genl_cpu_capability_event() stub
thermal: Replace acpi_bus_get_device()
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu feature updates from Borislav Petkov:
- Merge the AMD and Intel PPIN code into a shared one by both vendors.
Add the PPIN number to sysfs so that sockets can be identified when
replacement is needed
- Minor fixes and cleanups
* tag 'x86_cpu_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Clear SME feature flag when not in use
x86/cpufeatures: Put the AMX macros in the word 18 block
topology/sysfs: Add PPIN in sysfs under cpu topology
topology/sysfs: Add format parameter to macro defining "show" functions for proc
x86/cpu: Read/save PPIN MSR during initialization
x86/cpu: X86_FEATURE_INTEL_PPIN finally has a CPUID bit
x86/cpu: Merge Intel and AMD ppin_init() functions
x86/CPU/AMD: Use default_groups in kobj_type
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Conflicts:
arch/x86/include/asm/cpufeatures.h
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The bits required to make the hardware go.. Of note is that, provided
the syscall entry points are covered with ENDBR, #CP doesn't need to
be an IST because we'll never hit the syscall gap.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154318.582331711@infradead.org
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The RETPOLINE_AMD name is unfortunate since it isn't necessarily
AMD only, in fact Hygon also uses it. Furthermore it will likely be
sufficient for some Intel processors. Therefore rename the thing to
RETPOLINE_LFENCE to better describe what it is.
Add the spectre_v2=retpoline,lfence option as an alias to
spectre_v2=retpoline,amd to preserve existing setups. However, the output
of /sys/devices/system/cpu/vulnerabilities/spectre_v2 will be changed.
[ bp: Fix typos, massage. ]
Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
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These macros are for bits in CPUID.(EAX=7,ECX=0):EDX, not for bits in
CPUID(EAX=7,ECX=1):EAX. Put them with their brethren.
[ bp: Sort word 18 bits properly, as caught by Like Xu
<like.xu.linux@gmail.com> ]
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20220203194308.2469117-1-jmattson@google.com
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Add the CPUID feature bit and the model-specific registers needed to
identify and configure the Intel Hardware Feedback Interface.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Pull kvm updates from Paolo Bonzini:
"RISCV:
- Use common KVM implementation of MMU memory caches
- SBI v0.2 support for Guest
- Initial KVM selftests support
- Fix to avoid spurious virtual interrupts after clearing hideleg CSR
- Update email address for Anup and Atish
ARM:
- Simplification of the 'vcpu first run' by integrating it into KVM's
'pid change' flow
- Refactoring of the FP and SVE state tracking, also leading to a
simpler state and less shared data between EL1 and EL2 in the nVHE
case
- Tidy up the header file usage for the nvhe hyp object
- New HYP unsharing mechanism, finally allowing pages to be unmapped
from the Stage-1 EL2 page-tables
- Various pKVM cleanups around refcounting and sharing
- A couple of vgic fixes for bugs that would trigger once the vcpu
xarray rework is merged, but not sooner
- Add minimal support for ARMv8.7's PMU extension
- Rework kvm_pgtable initialisation ahead of the NV work
- New selftest for IRQ injection
- Teach selftests about the lack of default IPA space and page sizes
- Expand sysreg selftest to deal with Pointer Authentication
- The usual bunch of cleanups and doc update
s390:
- fix sigp sense/start/stop/inconsistency
- cleanups
x86:
- Clean up some function prototypes more
- improved gfn_to_pfn_cache with proper invalidation, used by Xen
emulation
- add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery
- completely remove potential TOC/TOU races in nested SVM consistency
checks
- update some PMCs on emulated instructions
- Intel AMX support (joint work between Thomas and Intel)
- large MMU cleanups
- module parameter to disable PMU virtualization
- cleanup register cache
- first part of halt handling cleanups
- Hyper-V enlightened MSR bitmap support for nested hypervisors
Generic:
- clean up Makefiles
- introduce CONFIG_HAVE_KVM_DIRTY_RING
- optimize memslot lookup using a tree
- optimize vCPU array usage by converting to xarray"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (268 commits)
x86/fpu: Fix inline prefix warnings
selftest: kvm: Add amx selftest
selftest: kvm: Move struct kvm_x86_state to header
selftest: kvm: Reorder vcpu_load_state steps for AMX
kvm: x86: Disable interception for IA32_XFD on demand
x86/fpu: Provide fpu_sync_guest_vmexit_xfd_state()
kvm: selftests: Add support for KVM_CAP_XSAVE2
kvm: x86: Add support for getting/setting expanded xstate buffer
x86/fpu: Add uabi_size to guest_fpu
kvm: x86: Add CPUID support for Intel AMX
kvm: x86: Add XCR0 support for Intel AMX
kvm: x86: Disable RDMSR interception of IA32_XFD_ERR
kvm: x86: Emulate IA32_XFD_ERR for guest
kvm: x86: Intercept #NM for saving IA32_XFD_ERR
x86/fpu: Prepare xfd_err in struct fpu_guest
kvm: x86: Add emulation for IA32_XFD
x86/fpu: Provide fpu_update_guest_xfd() for IA32_XFD emulation
kvm: x86: Enable dynamic xfeatures at KVM_SET_CPUID2
x86/fpu: Provide fpu_enable_guest_xfd_features() for KVM
x86/fpu: Add guest support to xfd_enable_feature()
...
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