Rename init_vmcb_after_set_cpuid() to svm_recalc_intercepts_after_set_cpuid()
to more precisely describe its role. Strictly speaking, the name isn't
perfect as toggling virtual VM{LOAD,SAVE} is arguably not recalculating an
intercept, but practically speaking it's close enough.
No functional change intended.
Link: https://lore.kernel.org/r/20250610225737.156318-22-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Rename msr_filter_changed() to recalc_msr_intercepts() and drop the
trampoline wrapper now that both SVM and VMX use a filter-agnostic recalc
helper to react to the new userspace filter.
No functional change intended.
Reviewed-by: Xin Li (Intel) <xin@zytor.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-21-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
On a userspace MSR filter change, recalculate all MSR intercepts using the
filter-agnostic logic instead of maintaining a "shadow copy" of KVM's
desired intercepts. The shadow bitmaps add yet another point of failure,
are confusing (e.g. what does "handled specially" mean!?!?), an eyesore,
and a maintenance burden.
Given that KVM *must* be able to recalculate the correct intercepts at any
given time, and that MSR filter updates are not hot paths, there is zero
benefit to maintaining the shadow bitmaps.
Opportunistically switch from boot_cpu_has() to cpu_feature_enabled() as
appropriate.
Link: https://lore.kernel.org/all/aCdPbZiYmtni4Bjs@google.com
Link: https://lore.kernel.org/all/20241126180253.GAZ0YNTdXH1UGeqsu6@fat_crate.local
Cc: Francesco Lavra <francescolavra.fl@gmail.com>
Link: https://lore.kernel.org/r/20250610225737.156318-20-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
On a userspace MSR filter change, recalculate all MSR intercepts using the
filter-agnostic logic instead of maintaining a "shadow copy" of KVM's
desired intercepts. The shadow bitmaps add yet another point of failure,
are confusing (e.g. what does "handled specially" mean!?!?), an eyesore,
and a maintenance burden.
Given that KVM *must* be able to recalculate the correct intercepts at any
given time, and that MSR filter updates are not hot paths, there is zero
benefit to maintaining the shadow bitmaps.
Opportunistically switch from boot_cpu_has() to cpu_feature_enabled() as
appropriate.
Link: https://lore.kernel.org/all/aCdPbZiYmtni4Bjs@google.com
Link: https://lore.kernel.org/all/20241126180253.GAZ0YNTdXH1UGeqsu6@fat_crate.local
Cc: Borislav Petkov <bp@alien8.de>
Reviewed-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Xin Li (Intel) <xin@zytor.com>
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-19-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Dedup the definition of X2APIC_MSR and put it in the local APIC code
where it belongs.
No functional change intended.
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-18-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Drop the "always" flag from the array of possible passthrough MSRs, and
instead manually initialize the permissions for the handful of MSRs that
KVM passes through by default. In addition to cutting down on boilerplate
copy+paste code and eliminating a misleading flag (the MSRs aren't always
passed through, e.g. thanks to MSR filters), this will allow for removing
the direct_access_msrs array entirely.
Link: https://lore.kernel.org/r/20250610225737.156318-17-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Disable interception of the GHCB MSR if and only if the VM is an SEV-ES
guest. While the exact behavior is completely undocumented in the APM,
common sense and testing on SEV-ES capable CPUs says that accesses to the
GHCB from non-SEV-ES guests will #GP. I.e. from the guest's perspective,
no functional change intended.
Fixes: 376c6d2850 ("KVM: SVM: Provide support for SEV-ES vCPU creation/loading")
Link: https://lore.kernel.org/r/20250610225737.156318-16-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add and use SVM MSR interception APIs (in most paths) to match VMX's
APIs and nomenclature. Specifically, add SVM variants of:
vmx_disable_intercept_for_msr(vcpu, msr, type)
vmx_enable_intercept_for_msr(vcpu, msr, type)
vmx_set_intercept_for_msr(vcpu, msr, type, intercept)
to eventually replace SVM's single helper:
set_msr_interception(vcpu, msrpm, msr, allow_read, allow_write)
which is awkward to use (in all cases, KVM either applies the same logic
for both reads and writes, or intercepts one of read or write), and is
unintuitive due to using '0' to indicate interception should be *set*.
Keep the guts of the old API for the moment to avoid churning the MSR
filter code, as that mess will be overhauled in the near future. Leave
behind a temporary comment to call out that the shadow bitmaps have
inverted polarity relative to the bitmaps consumed by hardware.
No functional change intended.
Reviewed-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-15-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add macro-built helpers for testing, setting, and clearing MSRPM entries
without relying on precomputed offsets. This sets the stage for eventually
removing general KVM use of precomputed offsets, which are quite confusing
and rather inefficient for the vast majority of KVM's usage.
Outside of merging L0 and L1 bitmaps for nested SVM, using u32-indexed
offsets and accesses is at best unnecessary, and at worst introduces extra
operations to retrieve the individual bit from within the offset u32 value.
And simply calling them "offsets" is very confusing, as the "unit" of the
offset isn't immediately obvious.
Use the new helpers in set_msr_interception_bitmap() and
msr_write_intercepted() to verify the math and operations, but keep the
existing offset-based logic in set_msr_interception_bitmap() to sanity
check the "clear" and "set" operations. Manipulating MSR interceptions
isn't a hot path and no kernel release is ever expected to contain this
specific version of set_msr_interception_bitmap() (it will be removed
entirely in the near future).
Link: https://lore.kernel.org/r/20250610225737.156318-14-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Don't initialize vmcb02's MSRPM with KVM's set of "always passthrough"
MSRs, as KVM always needs to consult L1's intercepts, i.e. needs to merge
vmcb01 with vmcb12 and write the result to vmcb02. This will eventually
allow for the removal of svm_vcpu_init_msrpm().
Note, the bitmaps are truly initialized by svm_vcpu_alloc_msrpm() (default
to intercepting all MSRs), e.g. if there is a bug lurking elsewhere, the
worst case scenario from dropping the call to svm_vcpu_init_msrpm() should
be that KVM would fail to passthrough MSRs to L2.
Link: https://lore.kernel.org/r/20250610225737.156318-13-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Don't merge bitmaps on nested VMRUN for MSRs that KVM passes through only
for SEV-ES guests. KVM doesn't support nested virtualization for SEV-ES,
and likely never will.
Link: https://lore.kernel.org/r/20250610225737.156318-12-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use a dedicated array of MSRPM offsets to merge L0 and L1 bitmaps, i.e. to
merge KVM's vmcb01 bitmap with L1's vmcb12 bitmap. This will eventually
allow for the removal of direct_access_msrs, as the only path where
tracking the offsets is truly justified is the merge for nested SVM, where
merging in chunks is an easy way to batch uaccess reads/writes.
Opportunistically omit the x2APIC MSRs from the merge-specific array
instead of filtering them out at runtime.
Note, disabling interception of DEBUGCTL, XSS, EFER, PAT, GHCB, and
TSC_AUX is mutually exclusive with nested virtualization, as KVM passes
through those MSRs only for SEV-ES guests, and KVM doesn't support nested
virtualization for SEV+ guests. Defer removing those MSRs to a future
cleanup in order to make this refactoring as benign as possible.
Link: https://lore.kernel.org/r/20250610225737.156318-11-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Move SVM's MSR Permissions Map macros to svm.h in anticipation of adding
helpers that are available to SVM code, and opportunistically replace a
variety of open-coded literals with (hopefully) informative macros.
Opportunistically open code ARRAY_SIZE(msrpm_ranges) instead of wrapping
it as NUM_MSR_MAPS, which is an ambiguous name even if it were qualified
with "SVM_MSRPM".
Deliberately leave the ranges as open coded literals, as using macros to
define the ranges actually introduces more potential failure points, since
both the definitions and the usage have to be careful to use the correct
index. The lack of clear intent behind the ranges will be addressed in
future patches.
No functional change intended.
Link: https://lore.kernel.org/r/20250610225737.156318-10-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Rename nested_svm_vmrun_msrpm() to nested_svm_merge_msrpm() to better
capture its role, and opportunistically feed it @vcpu instead of @svm, as
grabbing "svm" only to turn around and grab svm->vcpu is rather silly.
No functional change intended.
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-9-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Manipulate the MSR bitmaps using non-atomic bit ops APIs (two underscores),
as the bitmaps are per-vCPU and are only ever accessed while vcpu->mutex is
held.
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
WARN and kill the VM instead of panicking the host if KVM attempts to set
or query MSR interception for an unsupported MSR. Accessing the MSR
interception bitmaps only meaningfully affects post-VMRUN behavior, and
KVM_BUG_ON() is guaranteed to prevent the current vCPU from doing VMRUN,
i.e. there is no need to panic the entire host.
Opportunistically move the sanity checks about their use to index into the
MSRPM, e.g. so that bugs only WARN and terminate the VM, as opposed to
doing that _and_ generating an out-of-bounds load.
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Drop the unnecessary and dangerous value-terminated behavior of
direct_access_msrs, and simply iterate over the actual size of the array.
The use in svm_set_x2apic_msr_interception() is especially sketchy, as it
relies on unused capacity being zero-initialized, and '0' being outside
the range of x2APIC MSRs.
To ensure the array and shadow_msr_intercept stay synchronized, simply
assert that their sizes are identical (note the six 64-bit-only MSRs).
Note, direct_access_msrs will soon be removed entirely; keeping the assert
synchronized with the array isn't expected to be along-term maintenance
burden.
Reviewed-by: Chao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Tag init_msrpm_offsets() and add_msr_offset() with __init, as they're used
only during hardware setup to map potential passthrough MSRs to offsets in
the bitmap.
Reviewed-by: Chao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
WARN and reject module loading if there is a problem with KVM's MSR
interception bitmaps. Panicking the host in this situation is inexcusable
since it is trivially easy to propagate the error up the stack.
Link: https://lore.kernel.org/r/20250610225737.156318-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Allocate pages for the IOPM after initial setup has been completed in
svm_hardware_setup(), so that sanity checks can be added in the setup flow
without needing to free the IOPM pages. The IOPM is only referenced (via
iopm_base) in init_vmcb() and svm_hardware_unsetup(), so there's no need
to allocate it early on.
No functional change intended (beyond the obvious ordering differences,
e.g. if the allocation fails).
Link: https://lore.kernel.org/r/20250610225737.156318-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Disable interception of SPEC_CTRL when the CPU virtualizes (i.e. context
switches) SPEC_CTRL if and only if the MSR exists according to the vCPU's
CPUID model. Letting the guest access SPEC_CTRL is generally benign, but
the guest would see inconsistent behavior if KVM happened to emulate an
access to the MSR.
Fixes: d00b99c514 ("KVM: SVM: Add support for Virtual SPEC_CTRL")
Reported-by: Chao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Set/clear DEBUGCTLMSR_FREEZE_IN_SMM in GUEST_IA32_DEBUGCTL based on the
host's pre-VM-Enter value, i.e. preserve the host's FREEZE_IN_SMM setting
while running the guest. When running with the "default treatment of SMIs"
in effect (the only mode KVM supports), SMIs do not generate a VM-Exit that
is visible to host (non-SMM) software, and instead transitions directly
from VMX non-root to SMM. And critically, DEBUGCTL isn't context switched
by hardware on SMI or RSM, i.e. SMM will run with whatever value was
resident in hardware at the time of the SMI.
Failure to preserve FREEZE_IN_SMM results in the PMU unexpectedly counting
events while the CPU is executing in SMM, which can pollute profiling and
potentially leak information into the guest.
Check for changes in FREEZE_IN_SMM prior to every entry into KVM's inner
run loop, as the bit can be toggled in IRQ context via IPI callback (SMP
function call), by way of /sys/devices/cpu/freeze_on_smi.
Add a field in kvm_x86_ops to communicate which DEBUGCTL bits need to be
preserved, as FREEZE_IN_SMM is only supported and defined for Intel CPUs,
i.e. explicitly checking FREEZE_IN_SMM in common x86 is at best weird, and
at worst could lead to undesirable behavior in the future if AMD CPUs ever
happened to pick up a collision with the bit.
Exempt TDX vCPUs, i.e. protected guests, from the check, as the TDX Module
owns and controls GUEST_IA32_DEBUGCTL.
WARN in SVM if KVM_RUN_LOAD_DEBUGCTL is set, mostly to document that the
lack of handling isn't a KVM bug (TDX already WARNs on any run_flag).
Lastly, explicitly reload GUEST_IA32_DEBUGCTL on a VM-Fail that is missed
by KVM but detected by hardware, i.e. in nested_vmx_restore_host_state().
Doing so avoids the need to track host_debugctl on a per-VMCS basis, as
GUEST_IA32_DEBUGCTL is unconditionally written by prepare_vmcs02() and
load_vmcs12_host_state(). For the VM-Fail case, even though KVM won't
have actually entered the guest, vcpu_enter_guest() will have run with
vmcs02 active and thus could result in vmcs01 being run with a stale value.
Cc: stable@vger.kernel.org
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20250610232010.162191-9-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Introduce vmx_guest_debugctl_{read,write}() to handle all accesses to
vmcs.GUEST_IA32_DEBUGCTL. This will allow stuffing FREEZE_IN_SMM into
GUEST_IA32_DEBUGCTL based on the host setting without bleeding the state
into the guest, and without needing to copy+paste the FREEZE_IN_SMM
logic into every patch that accesses GUEST_IA32_DEBUGCTL.
No functional change intended.
Cc: stable@vger.kernel.org
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
[sean: massage changelog, make inline, use in all prepare_vmcs02() cases]
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250610232010.162191-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add a consistency check for L2's guest_ia32_debugctl, as KVM only supports
a subset of hardware functionality, i.e. KVM can't rely on hardware to
detect illegal/unsupported values. Failure to check the vmcs12 value
would allow the guest to load any harware-supported value while running L2.
Take care to exempt BTF and LBR from the validity check in order to match
KVM's behavior for writes via WRMSR, but without clobbering vmcs12. Even
if VM_EXIT_SAVE_DEBUG_CONTROLS is set in vmcs12, L1 can reasonably expect
that vmcs12->guest_ia32_debugctl will not be modified if writes to the MSR
are being intercepted.
Arguably, KVM _should_ update vmcs12 if VM_EXIT_SAVE_DEBUG_CONTROLS is set
*and* writes to MSR_IA32_DEBUGCTLMSR are not being intercepted by L1, but
that would incur non-trivial complexity and wouldn't change the fact that
KVM's handling of DEBUGCTL is blatantly broken. I.e. the extra complexity
is not worth carrying.
Cc: stable@vger.kernel.org
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20250610232010.162191-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Move VMX's logic to check DEBUGCTL values into a standalone helper so that
the code can be used by nested VM-Enter to apply the same logic to the
value being loaded from vmcs12.
KVM needs to explicitly check vmcs12->guest_ia32_debugctl on nested
VM-Enter, as hardware may support features that KVM does not, i.e. relying
on hardware to detect invalid guest state will result in false negatives.
Unfortunately, that means applying KVM's funky suppression of BTF and LBR
to vmcs12 so as not to break existing guests.
No functional change intended.
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250610232010.162191-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Let the guest set DEBUGCTL.RTM_DEBUG if RTM is supported according to the
guest CPUID model, as debug support is supposed to be available if RTM is
supported, and there are no known downsides to letting the guest debug RTM
aborts.
Note, there are no known bug reports related to RTM_DEBUG, the primary
motivation is to reduce the probability of breaking existing guests when a
future change adds a missing consistency check on vmcs12.GUEST_DEBUGCTL
(KVM currently lets L2 run with whatever hardware supports; whoops).
Note #2, KVM already emulates DR6.RTM, and doesn't restrict access to
DR7.RTM.
Fixes: 83c529151a ("KVM: x86: expose Intel cpu new features (HLE, RTM) to guest")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250610232010.162191-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Instruct vendor code to load the guest's DR6 into hardware via a new
KVM_RUN flag, and remove kvm_x86_ops.set_dr6(), whose sole purpose was to
load vcpu->arch.dr6 into hardware when DR6 can be read/written directly
by the guest.
Note, TDX already WARNs on any run_flag being set, i.e. will yell if KVM
thinks DR6 needs to be reloaded. TDX vCPUs force KVM_DEBUGREG_AUTO_SWITCH
and never clear the flag, i.e. should never observe KVM_RUN_LOAD_GUEST_DR6.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250610232010.162191-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Convert kvm_x86_ops.vcpu_run()'s "force_immediate_exit" boolean parameter
into an a generic bitmap so that similar "take action" information can be
passed to vendor code without creating a pile of boolean parameters.
This will allow dropping kvm_x86_ops.set_dr6() in favor of a new flag, and
will also allow for adding similar functionality for re-loading debugctl
in the active VMCS.
Opportunistically massage the TDX WARN and comment to prepare for adding
more run_flags, all of which are expected to be mutually exclusive with
TDX, i.e. should be WARNed on.
No functional change intended.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250610232010.162191-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Use the kvm_arch_vcpu.host_debugctl snapshot to restore DEBUGCTL after
running a TD vCPU. The final TDX series rebase was mishandled, likely due
to commit fb71c79593 ("KVM: x86: Snapshot the host's DEBUGCTL in common
x86") deleting the same line of code from vmx.h, i.e. creating a semantic
conflict of sorts, but no syntactic conflict.
Using the version in kvm_vcpu_arch picks up the ulong => u64 fix (which
isn't relevant to TDX) as well as the IRQ fix from commit 189ecdb3e1
("KVM: x86: Snapshot the host's DEBUGCTL after disabling IRQs").
Link: https://lore.kernel.org/all/20250307212053.2948340-10-pbonzini@redhat.com
Cc: Adrian Hunter <adrian.hunter@intel.com>
Fixes: 8af0990375 ("KVM: TDX: Save and restore IA32_DEBUGCTL")
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20250610232010.162191-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
ath79_misc_irq_init() was defined but unused since commit 51fa4f8912
("MIPS: ath79: drop legacy IRQ code"), so it's time to drop it.
The build also warns about a missing prototype of get_c0_perfcount_int().
Remove the stale leftover function and add the missing include.
Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/OSBPR01MB167032D2017645200787AAEBBC72A@OSBPR01MB1670.jpnprd01.prod.outlook.com
As part of this WA GuC will save and restore value of two XE3_Media
control registers that were not included in the HW power context.
v2:
- Update klv name (Badal)
Signed-off-by: sanirban <sk.anirban@intel.com>
Reviewed-by: Badal Nilawar <badal.nilawar@intel.com>
Link: https://lore.kernel.org/r/20250619133413.107423-2-sk.anirban@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Currently the call_rcu() API does not check whether a callback
pointer is NULL. If NULL is passed, rcu_core() will try to invoke
it, resulting in NULL pointer dereference and a kernel crash.
To prevent this and improve debuggability, this patch adds a check
for NULL and emits a kernel stack trace to help identify a faulty
caller.
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
In function dump_xx_nlmsg(), when realloc() fails to allocate memory,
the original pointer to the buffer is overwritten with NULL. This causes
a memory leak because the previously allocated buffer becomes unreachable
without being freed.
Fixes: 7900efc192 ("tools/bpf: bpftool: improve output format for bpftool net")
Signed-off-by: Yuan Chen <chenyuan@kylinos.cn>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20250620012133.14819-1-chenyuan_fl@163.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Allow userspace to advertise TDG.VP.VMCALL subfunctions that the
kernel also supports. For each output register of GetTdVmCallInfo's
leaf 1, add two fields to KVM_TDX_CAPABILITIES: one for kernel-supported
TDVMCALLs (userspace can set those blindly) and one for user-supported
TDVMCALLs (userspace can set those if it knows how to handle them).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add selftest cases that validate bpftool's expected behavior when
accessing maps protected from modification via security_bpf_map.
The test includes a BPF program attached to security_bpf_map with two maps:
- A protected map that only allows read-only access
- An unprotected map that allows full access
The test script attaches the BPF program to security_bpf_map and
verifies that for the bpftool map command:
- Read access works on both maps
- Write access fails on the protected map
- Write access succeeds on the unprotected map
- These behaviors remain consistent when the maps are pinned
Signed-off-by: Slava Imameev <slava.imameev@crowdstrike.com>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20250620151812.13952-2-slava.imameev@crowdstrike.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Modify several functions in tools/bpf/bpftool/common.c to allow
specification of requested access for file descriptors, such as
read-only access.
Update bpftool to request only read access for maps when write
access is not required. This fixes errors when reading from maps
that are protected from modification via security_bpf_map.
Signed-off-by: Slava Imameev <slava.imameev@crowdstrike.com>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20250620151812.13952-1-slava.imameev@crowdstrike.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Exit to userspace for TDG.VP.VMCALL<GetTdVmCallInfo> via KVM_EXIT_TDX,
to allow userspace to provide information about the support of
TDVMCALLs when r12 is 1 for the TDVMCALLs beyond the GHCI base API.
GHCI spec defines the GHCI base TDVMCALLs: <GetTdVmCallInfo>, <MapGPA>,
<ReportFatalError>, <Instruction.CPUID>, <#VE.RequestMMIO>,
<Instruction.HLT>, <Instruction.IO>, <Instruction.RDMSR> and
<Instruction.WRMSR>. They must be supported by VMM to support TDX guests.
For GetTdVmCallInfo
- When leaf (r12) to enumerate TDVMCALL functionality is set to 0,
successful execution indicates all GHCI base TDVMCALLs listed above are
supported.
Update the KVM TDX document with the set of the GHCI base APIs.
- When leaf (r12) to enumerate TDVMCALL functionality is set to 1, it
indicates the TDX guest is querying the supported TDVMCALLs beyond
the GHCI base TDVMCALLs.
Exit to userspace to let userspace set the TDVMCALL sub-function bit(s)
accordingly to the leaf outputs. KVM could set the TDVMCALL bit(s)
supported by itself when the TDVMCALLs don't need support from userspace
after returning from userspace and before entering guest. Currently, no
such TDVMCALLs implemented, KVM just sets the values returned from
userspace.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
[Adjust userspace API. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The EFI call in start_kernel() is guarded by #ifdef CONFIG_X86. Move
the thing to the arch_cpu_finalize_init() path on x86 and get rid of
the #ifdef in start_kernel().
No functional change intended.
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@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: Sohil Mehta <sohil.mehta@intel.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/all/20250620135325.3300848-5-kirill.shutemov%40linux.intel.com
Handle TDVMCALL for GetQuote to generate a TD-Quote.
GetQuote is a doorbell-like interface used by TDX guests to request VMM
to generate a TD-Quote signed by a service hosting TD-Quoting Enclave
operating on the host. A TDX guest passes a TD Report (TDREPORT_STRUCT) in
a shared-memory area as parameter. Host VMM can access it and queue the
operation for a service hosting TD-Quoting enclave. When completed, the
Quote is returned via the same shared-memory area.
KVM only checks the GPA from the TDX guest has the shared-bit set and drops
the shared-bit before exiting to userspace to avoid bleeding the shared-bit
into KVM's exit ABI. KVM forwards the request to userspace VMM (e.g. QEMU)
and userspace VMM queues the operation asynchronously. KVM sets the return
code according to the 'ret' field set by userspace to notify the TDX guest
whether the request has been queued successfully or not. When the request
has been queued successfully, the TDX guest can poll the status field in
the shared-memory area to check whether the Quote generation is completed
or not. When completed, the generated Quote is returned via the same
buffer.
Add KVM_EXIT_TDX as a new exit reason to userspace. Userspace is
required to handle the KVM exit reason as the initial support for TDX,
by reentering KVM to ensure that the TDVMCALL is complete. While at it,
add a note that KVM_EXIT_HYPERCALL also requires reentry with KVM_RUN.
Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
Tested-by: Mikko Ylinen <mikko.ylinen@linux.intel.com>
Acked-by: Kai Huang <kai.huang@intel.com>
[Adjust userspace API. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the new TDVMCALL status code TDVMCALL_STATUS_SUBFUNC_UNSUPPORTED and
return it for unimplemented TDVMCALL subfunctions.
Returning TDVMCALL_STATUS_INVALID_OPERAND when a subfunction is not
implemented is vague because TDX guests can't tell the error is due to
the subfunction is not supported or an invalid input of the subfunction.
New GHCI spec adds TDVMCALL_STATUS_SUBFUNC_UNSUPPORTED to avoid the
ambiguity. Use it instead of TDVMCALL_STATUS_INVALID_OPERAND.
Before the change, for common guest implementations, when a TDX guest
receives TDVMCALL_STATUS_INVALID_OPERAND, it has two cases:
1. Some operand is invalid. It could change the operand to another value
retry.
2. The subfunction is not supported.
For case 1, an invalid operand usually means the guest implementation bug.
Since the TDX guest can't tell which case is, the best practice for
handling TDVMCALL_STATUS_INVALID_OPERAND is stopping calling such leaf,
treating the failure as fatal if the TDVMCALL is essential or ignoring
it if the TDVMCALL is optional.
With this change, TDVMCALL_STATUS_SUBFUNC_UNSUPPORTED could be sent to
old TDX guest that do not know about it, but it is expected that the
guest will make the same action as TDVMCALL_STATUS_INVALID_OPERAND.
Currently, no known TDX guest checks TDVMCALL_STATUS_INVALID_OPERAND
specifically; for example Linux just checks for success.
Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
[Return it for untrapped KVM_HC_MAP_GPA_RANGE. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- correct the ACPI GPIO access mode in gpio-loongson-64bit
- only obtain the interrupt for a single instance of the chip controlled
by gpio-mlxbf3
- fix an invalid value return from probe() in gpio-pca953x
- add missing MODULE_DEVICE_TABLE() to gpio-spacemit
- update the HiSilicon GPIO driver maintainer entry
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Merge tag 'gpio-fixes-for-v6.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio fixes from Bartosz Golaszewski:
- correct the ACPI GPIO access mode in gpio-loongson-64bit
- only obtain the interrupt for a single instance of the chip
controlled by gpio-mlxbf3
- fix an invalid value return from probe() in gpio-pca953x
- add missing MODULE_DEVICE_TABLE() to gpio-spacemit
- update the HiSilicon GPIO driver maintainer entry
* tag 'gpio-fixes-for-v6.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio: mlxbf3: only get IRQ for device instance 0
gpio: pca953x: fix wrong error probe return value
gpio: spacemit: Add missing MODULE_DEVICE_TABLE
gpio: loongson-64bit: Correct Loongson-7A2000 ACPI GPIO access mode
MAINTAINERS: Update HiSilicon GPIO driver maintainer
- Fix another set of FP/SIMD/SVE bugs affecting NV, and plugging some
missing synchronisation
- A small fix for the irqbypass hook fixes, tightening the check and
ensuring that we only deal with MSI for both the old and the new
route entry
- Rework the way the shadow LRs are addressed in a nesting
configuration, plugging an embarrassing bug as well as simplifying
the whole process
- Add yet another fix for the dreaded arch_timer_edge_cases selftest
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Merge tag 'kvmarm-fixes-6.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 fixes for 6.16, take #3
- Fix another set of FP/SIMD/SVE bugs affecting NV, and plugging some
missing synchronisation
- A small fix for the irqbypass hook fixes, tightening the check and
ensuring that we only deal with MSI for both the old and the new
route entry
- Rework the way the shadow LRs are addressed in a nesting
configuration, plugging an embarrassing bug as well as simplifying
the whole process
- Add yet another fix for the dreaded arch_timer_edge_cases selftest
A collection of small fixes.
All changes are device-specific at this time.
- Fixes for Cirrus codecs with SoundWire, including firmware name
updates
- Fix for i.MX8 SoC DSP
- Usual HD-audio, USB-audio, and ASoC AMD quirks
- Fixes for legendary SoundBlaster AWE32 ISA device (a real one, we
still got a bug report after 25 years)
- Minor build fixes
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Merge tag 'sound-6.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"A collection of small fixes. All changes are device-specific at this
time:
- Fixes for Cirrus codecs with SoundWire, including firmware name
updates
- Fix for i.MX8 SoC DSP
- Usual HD-audio, USB-audio, and ASoC AMD quirks
- Fixes for legendary SoundBlaster AWE32 ISA device (a real one, we
still got a bug report after 25 years)
- Minor build fixes"
* tag 'sound-6.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (24 commits)
ALSA: hda/realtek: Enable headset Mic on Positivo P15X
ASoC: Intel: sof-function-topology-lib: Print out the unsupported dmic count
ASoC: doc: cs35l56: Add CS35L63 to the list of supported devices
ASoC: SOF: imx8: add core shutdown operation for imx8/imx8x
ALSA: hda/realtek: Add quirk for Asus GA605K
ALSA: hda/realtek: enable headset mic on Latitude 5420 Rugged
ASoC: amd: yc: update quirk data for HP Victus
ASoC: apple: mca: Drop default ARCH_APPLE in Kconfig
ALSA: usb-audio: Rename ALSA kcontrol PCM and PCM1 for the KTMicro sound card
ASoC: amd: yc: Add quirk for MSI Bravo 17 D7VF internal mic
ASoC: doc: cs35l56: Update to add new SoundWire firmware filename suffix
ASoC: cs35l56: Use SoundWire address as alternate firmware suffix on L56 B0
ASoC: cs35l56: Use SoundWire address as firmware name suffix for new silicon
ASoC: sdw_utils: Fix potential NULL pointer deref in is_sdca_endpoint_present()
ALSA: sb: Force to disable DMAs once when DMA mode is changed
ALSA: sb: Don't allow changing the DMA mode during operations
ALSA: hda/realtek: Add quirk for Asus GU605C
ALSA: hda/realtek: Fix built-in mic on ASUS VivoBook X513EA
ALSA: hda/realtek - Add mute LED support for HP Victus 16-s1xxx and HP Victus 15-fa1xxx
ALSA: ctxfi: Replace deprecated strcpy() with strscpy()
...
- Suppress KASAN false positive in stack unwinding code.
- Drop redundant reset of the GCS state on exec().
- Don't try to descend into a !present PMD when creating a huge vmap()
entry at the PUD level.
- Fix a small typo in the arm64 booting Documentation.
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"There's nothing major (even the vmalloc one is just suppressing a
potential warning) but all worth having, nonetheless.
- Suppress KASAN false positive in stack unwinding code
- Drop redundant reset of the GCS state on exec()
- Don't try to descend into a !present PMD when creating a huge
vmap() entry at the PUD level
- Fix a small typo in the arm64 booting Documentation"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64/ptrace: Fix stack-out-of-bounds read in regs_get_kernel_stack_nth()
arm64/gcs: Don't call gcs_free() during flush_gcs()
arm64: Restrict pagetable teardown to avoid false warning
docs: arm64: Fix ICC_SRE_EL2 register typo in booting.rst
Some modules have BT_EN enabled via a hardware pull-up,
meaning it is not defined in the DTS and is not controlled
through the power sequence. In such cases, fall through
to follow the legacy flow.
Signed-off-by: Shuai Zhang <quic_shuaz@quicinc.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
OBEX download from iPhone is currently slow due to small packet size
used to transfer data which doesn't follow the MTU negotiated during
L2CAP connection, i.e. 672 bytes instead of 32767:
< ACL Data TX: Handle 11 flags 0x00 dlen 12
L2CAP: Connection Request (0x02) ident 18 len 4
PSM: 4103 (0x1007)
Source CID: 72
> ACL Data RX: Handle 11 flags 0x02 dlen 16
L2CAP: Connection Response (0x03) ident 18 len 8
Destination CID: 14608
Source CID: 72
Result: Connection successful (0x0000)
Status: No further information available (0x0000)
< ACL Data TX: Handle 11 flags 0x00 dlen 27
L2CAP: Configure Request (0x04) ident 20 len 19
Destination CID: 14608
Flags: 0x0000
Option: Maximum Transmission Unit (0x01) [mandatory]
MTU: 32767
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 63
Max transmit: 3
Retransmission timeout: 2000
Monitor timeout: 12000
Maximum PDU size: 1009
> ACL Data RX: Handle 11 flags 0x02 dlen 26
L2CAP: Configure Request (0x04) ident 72 len 18
Destination CID: 72
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 32
Max transmit: 255
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 65527
Option: Frame Check Sequence (0x05) [mandatory]
FCS: 16-bit FCS (0x01)
< ACL Data TX: Handle 11 flags 0x00 dlen 29
L2CAP: Configure Response (0x05) ident 72 len 21
Source CID: 14608
Flags: 0x0000
Result: Success (0x0000)
Option: Maximum Transmission Unit (0x01) [mandatory]
MTU: 672
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 32
Max transmit: 255
Retransmission timeout: 2000
Monitor timeout: 12000
Maximum PDU size: 1009
> ACL Data RX: Handle 11 flags 0x02 dlen 32
L2CAP: Configure Response (0x05) ident 20 len 24
Source CID: 72
Flags: 0x0000
Result: Success (0x0000)
Option: Maximum Transmission Unit (0x01) [mandatory]
MTU: 32767
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 63
Max transmit: 3
Retransmission timeout: 2000
Monitor timeout: 12000
Maximum PDU size: 1009
Option: Frame Check Sequence (0x05) [mandatory]
FCS: 16-bit FCS (0x01)
...
> ACL Data RX: Handle 11 flags 0x02 dlen 680
Channel: 72 len 676 ctrl 0x0202 [PSM 4103 mode Enhanced Retransmission (0x03)] {chan 8}
I-frame: Unsegmented TxSeq 1 ReqSeq 2
< ACL Data TX: Handle 11 flags 0x00 dlen 13
Channel: 14608 len 9 ctrl 0x0204 [PSM 4103 mode Enhanced Retransmission (0x03)] {chan 8}
I-frame: Unsegmented TxSeq 2 ReqSeq 2
> ACL Data RX: Handle 11 flags 0x02 dlen 680
Channel: 72 len 676 ctrl 0x0304 [PSM 4103 mode Enhanced Retransmission (0x03)] {chan 8}
I-frame: Unsegmented TxSeq 2 ReqSeq 3
The MTUs are negotiated for each direction. In this traces 32767 for
iPhone->localhost and no MTU for localhost->iPhone, which based on
'4.4 L2CAP_CONFIGURATION_REQ' (Core specification v5.4, Vol. 3, Part
A):
The only parameters that should be included in the
L2CAP_CONFIGURATION_REQ packet are those that require different
values than the default or previously agreed values.
...
Any missing configuration parameters are assumed to have their
most recently explicitly or implicitly accepted values.
and '5.1 Maximum transmission unit (MTU)':
If the remote device sends a positive L2CAP_CONFIGURATION_RSP
packet it should include the actual MTU to be used on this channel
for traffic flowing into the local device.
...
The default value is 672 octets.
is set by BlueZ to 672 bytes.
It seems that the iPhone used the lowest negotiated value to transfer
data to the localhost instead of the negotiated one for the incoming
direction.
This could be fixed by using the MTU negotiated for the other
direction, if exists, in the L2CAP_CONFIGURATION_RSP.
This allows to use segmented packets as in the following traces:
< ACL Data TX: Handle 11 flags 0x00 dlen 12
L2CAP: Connection Request (0x02) ident 22 len 4
PSM: 4103 (0x1007)
Source CID: 72
< ACL Data TX: Handle 11 flags 0x00 dlen 27
L2CAP: Configure Request (0x04) ident 24 len 19
Destination CID: 2832
Flags: 0x0000
Option: Maximum Transmission Unit (0x01) [mandatory]
MTU: 32767
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 63
Max transmit: 3
Retransmission timeout: 2000
Monitor timeout: 12000
Maximum PDU size: 1009
> ACL Data RX: Handle 11 flags 0x02 dlen 26
L2CAP: Configure Request (0x04) ident 15 len 18
Destination CID: 72
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 32
Max transmit: 255
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 65527
Option: Frame Check Sequence (0x05) [mandatory]
FCS: 16-bit FCS (0x01)
< ACL Data TX: Handle 11 flags 0x00 dlen 29
L2CAP: Configure Response (0x05) ident 15 len 21
Source CID: 2832
Flags: 0x0000
Result: Success (0x0000)
Option: Maximum Transmission Unit (0x01) [mandatory]
MTU: 32767
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 32
Max transmit: 255
Retransmission timeout: 2000
Monitor timeout: 12000
Maximum PDU size: 1009
> ACL Data RX: Handle 11 flags 0x02 dlen 32
L2CAP: Configure Response (0x05) ident 24 len 24
Source CID: 72
Flags: 0x0000
Result: Success (0x0000)
Option: Maximum Transmission Unit (0x01) [mandatory]
MTU: 32767
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Enhanced Retransmission (0x03)
TX window size: 63
Max transmit: 3
Retransmission timeout: 2000
Monitor timeout: 12000
Maximum PDU size: 1009
Option: Frame Check Sequence (0x05) [mandatory]
FCS: 16-bit FCS (0x01)
...
> ACL Data RX: Handle 11 flags 0x02 dlen 1009
Channel: 72 len 1005 ctrl 0x4202 [PSM 4103 mode Enhanced Retransmission (0x03)] {chan 8}
I-frame: Start (len 21884) TxSeq 1 ReqSeq 2
> ACL Data RX: Handle 11 flags 0x02 dlen 1009
Channel: 72 len 1005 ctrl 0xc204 [PSM 4103 mode Enhanced Retransmission (0x03)] {chan 8}
I-frame: Continuation TxSeq 2 ReqSeq 2
This has been tested with kernel 5.4 and BlueZ 5.77.
Cc: stable@vger.kernel.org
Signed-off-by: Frédéric Danis <frederic.danis@collabora.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
