The KVM host kernel is running in HS-mode needs so we need to handle
the SBI calls coming from guest kernel running in VS-mode.
This patch adds SBI v0.1 support in KVM RISC-V. Almost all SBI v0.1
calls are implemented in KVM kernel module except GETCHAR and PUTCHART
calls which are forwarded to user space because these calls cannot be
implemented in kernel space. In future, when we implement SBI v0.2 for
Guest, we will forward SBI v0.2 experimental and vendor extension calls
to user space.
Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
RISC-V: KVM: Implement ONE REG interface for FP registers
Add a KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctl interface for floating
point registers such as F0-F31 and FCSR. This support is added for
both 'F' and 'D' extensions.
Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch adds floating point (F and D extension) context save/restore
for guest VCPUs. The FP context is saved and restored lazily only when
kernel enter/exits the in-kernel run loop and not during the KVM world
switch. This way FP save/restore has minimal impact on KVM performance.
Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
The RISC-V hypervisor specification doesn't have any virtual timer
feature.
Due to this, the guest VCPU timer will be programmed via SBI calls.
The host will use a separate hrtimer event for each guest VCPU to
provide timer functionality. We inject a virtual timer interrupt to
the guest VCPU whenever the guest VCPU hrtimer event expires.
This patch adds guest VCPU timer implementation along with ONE_REG
interface to access VCPU timer state from user space.
Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch implements all required functions for programming
the stage2 page table for each Guest/VM.
At high-level, the flow of stage2 related functions is similar
from KVM ARM/ARM64 implementation but the stage2 page table
format is quite different for KVM RISC-V.
We implement a simple VMID allocator for Guests/VMs which:
1. Detects number of VMID bits at boot-time
2. Uses atomic number to track VMID version and increments
VMID version whenever we run-out of VMIDs
3. Flushes Guest TLBs on all host CPUs whenever we run-out
of VMIDs
4. Force updates HW Stage2 VMID for each Guest VCPU whenever
VMID changes using VCPU request KVM_REQ_UPDATE_HGATP
Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
We get illegal instruction trap whenever Guest/VM executes WFI
instruction.
This patch handles WFI trap by blocking the trapped VCPU using
kvm_vcpu_block() API. The blocked VCPU will be automatically
resumed whenever a VCPU interrupt is injected from user-space
or from in-kernel IRQCHIP emulation.
Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
We will get stage2 page faults whenever Guest/VM access SW emulated
MMIO device or unmapped Guest RAM.
This patch implements MMIO read/write emulation by extracting MMIO
details from the trapped load/store instruction and forwarding the
MMIO read/write to user-space. The actual MMIO emulation will happen
in user-space and KVM kernel module will only take care of register
updates before resuming the trapped VCPU.
The handling for stage2 page faults for unmapped Guest RAM will be
implemeted by a separate patch later.
[jiangyifei: ioeventfd and in-kernel mmio device support] Signed-off-by: Yifei Jiang <jiangyifei@huawei.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch implements the VCPU world-switch for KVM RISC-V.
The KVM RISC-V world-switch (i.e. __kvm_riscv_switch_to()) mostly
switches general purpose registers, SSTATUS, STVEC, SSCRATCH and
HSTATUS CSRs. Other CSRs are switched via vcpu_load() and vcpu_put()
interface in kvm_arch_vcpu_load() and kvm_arch_vcpu_put() functions
respectively.
Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access
VCPU config and registers from user-space.
We have three types of VCPU registers:
1. CONFIG - these are VCPU config and capabilities
2. CORE - these are VCPU general purpose registers
3. CSR - these are VCPU control and status registers
The CONFIG register available to user-space is ISA. The ISA register is
a read and write register where user-space can only write the desired
VCPU ISA capabilities before running the VCPU.
The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7,
T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except
PC and MODE. The PC register represents program counter whereas the MODE
register represent VCPU privilege mode (i.e. S/U-mode).
The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC,
SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers.
In future, more VCPU register types will be added (such as FP) for the
KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls.
Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
RISC-V: KVM: Implement VCPU interrupts and requests handling
This patch implements VCPU interrupts and requests which are both
asynchronous events.
The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from
user-space. In future, the in-kernel IRQCHIP emulation will use
kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt()
functions to set/unset VCPU interrupts.
Important VCPU requests implemented by this patch are:
KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state
KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested
The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request
and kvm_riscv_vcpu_has_interrupt() function.
The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added
later) to power-up a VCPU in power-off state. The user-space can use
the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU.
Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
RISC-V: KVM: Implement VCPU create, init and destroy functions
This patch implements VCPU create, init and destroy functions
required by generic KVM module. We don't have much dynamic
resources in struct kvm_vcpu_arch so these functions are quite
simple for KVM RISC-V.
Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch adds initial skeletal KVM RISC-V support which has:
1. A simple implementation of arch specific VM functions
except kvm_vm_ioctl_get_dirty_log() which will implemeted
in-future as part of stage2 page loging.
2. Stubs of required arch specific VCPU functions except
kvm_arch_vcpu_ioctl_run() which is semi-complete and
extended by subsequent patches.
3. Stubs for required arch specific stage2 MMU functions.
Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
KVM: selftests: Ensure all migrations are performed when test is affined
Rework the CPU selection in the migration worker to ensure the specified
number of migrations are performed when the test iteslf is affined to a
subset of CPUs. The existing logic skips iterations if the target CPU is
not in the original set of possible CPUs, which causes the test to fail
if too many iterations are skipped.
==== Test Assertion Failure ====
rseq_test.c:228: i > (NR_TASK_MIGRATIONS / 2)
pid=10127 tid=10127 errno=4 - Interrupted system call
1 0x00000000004018e5: main at rseq_test.c:227
2 0x00007fcc8fc66bf6: ?? ??:0
3 0x0000000000401959: _start at ??:?
Only performed 4 KVM_RUNs, task stalled too much?
Calculate the min/max possible CPUs as a cheap "best effort" to avoid
high runtimes when the test is affined to a small percentage of CPUs.
Alternatively, a list or xarray of the possible CPUs could be used, but
even in a horrendously inefficient setup, such optimizations are not
needed because the runtime is completely dominated by the cost of
migrating the task, and the absolute runtime is well under a minute in
even truly absurd setups, e.g. running on a subset of vCPUs in a VM that
is heavily overcommited (16 vCPUs per pCPU).
Fixes: 162ea980739d ("KVM: selftests: Add a test for KVM_RUN+rseq to detect task migration bugs") Reported-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210929234112.1862848-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Swap order of CPUID entry "index" vs. "significant flag" checks
Check whether a CPUID entry's index is significant before checking for a
matching index to hack-a-fix an undefined behavior bug due to consuming
uninitialized data. RESET/INIT emulation uses kvm_cpuid() to retrieve
CPUID.0x1, which does _not_ have a significant index, and fails to
initialize the dummy variable that doubles as EBX/ECX/EDX output _and_
ECX, a.k.a. index, input.
Practically speaking, it's _extremely_ unlikely any compiler will yield
code that causes problems, as the compiler would need to inline the
kvm_cpuid() call to detect the uninitialized data, and intentionally hose
the kernel, e.g. insert ud2, instead of simply ignoring the result of
the index comparison.
Although the sketchy "dummy" pattern was introduced in SVM by commit 13060218d09b ("KVM: x86: Make register state after reset conform to
specification"), it wasn't actually broken until commit b6dbd9db9dbf
("KVM: x86: Remove stateful CPUID handling") arbitrarily swapped the
order of operations such that "index" was checked before the significant
flag.
Avoid consuming uninitialized data by reverting to checking the flag
before the index purely so that the fix can be easily backported; the
offending RESET/INIT code has been refactored, moved, and consolidated
from vendor code to common x86 since the bug was introduced. A future
patch will directly address the bad RESET/INIT behavior.
The undefined behavior was detected by syzbot + KernelMemorySanitizer.
Local variable ----dummy@kvm_vcpu_reset created at:
kvm_vcpu_reset+0x1fb/0x1c20 arch/x86/kvm/x86.c:10812
kvm_apic_accept_events+0x58f/0x8c0 arch/x86/kvm/lapic.c:2923
Reported-by: syzbot+f3985126b746b3d59c9d@syzkaller.appspotmail.com Reported-by: Alexander Potapenko <glider@google.com> Fixes: 2083742e4fdc ("KVM: VMX: Set EDX at INIT with CPUID.0x1, Family-Model-Stepping") Fixes: b6dbd9db9dbf ("KVM: x86: Remove stateful CPUID handling") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20210929222426.1855730-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Zelin Deng [Wed, 29 Sep 2021 05:13:49 +0000 (13:13 +0800)]
ptp: Fix ptp_kvm_getcrosststamp issue for x86 ptp_kvm
hv_clock is preallocated to have only HVC_BOOT_ARRAY_SIZE (64) elements;
if the PTP_SYS_OFFSET_PRECISE ioctl is executed on vCPUs whose index is
64 of higher, retrieving the struct pvclock_vcpu_time_info pointer with
"src = &hv_clock[cpu].pvti" will result in an out-of-bounds access and
a wild pointer. Change it to "this_cpu_pvti()" which is guaranteed to
be valid.
Fixes: e43c1f615a16 ("Switch kvmclock data to a PER_CPU variable") Signed-off-by: Zelin Deng <zelin.deng@linux.alibaba.com> Cc: <stable@vger.kernel.org>
Message-Id: <1632892429-101194-3-git-send-email-zelin.deng@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Zelin Deng [Wed, 29 Sep 2021 05:13:48 +0000 (13:13 +0800)]
x86/kvmclock: Move this_cpu_pvti into kvmclock.h
There're other modules might use hv_clock_per_cpu variable like ptp_kvm,
so move it into kvmclock.h and export the symbol to make it visiable to
other modules.
Signed-off-by: Zelin Deng <zelin.deng@linux.alibaba.com> Cc: <stable@vger.kernel.org>
Message-Id: <1632892429-101194-2-git-send-email-zelin.deng@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Janosch Frank [Fri, 10 Sep 2021 08:04:20 +0000 (08:04 +0000)]
KVM: s390: Function documentation fixes
The latest compile changes pointed us to a few instances where we use
the kernel documentation style but don't explain all variables or
don't adhere to it 100%.
It's easy to fix so let's do that.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Oliver Upton [Mon, 27 Sep 2021 22:36:21 +0000 (22:36 +0000)]
selftests: KVM: Don't clobber XMM register when read
There is no need to clobber a register that is only being read from.
Oops. Drop the XMM register from the clobbers list.
Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20210927223621.50178-1-oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: VMX: Fix a TSX_CTRL_CPUID_CLEAR field mask issue
When updating the host's mask for its MSR_IA32_TSX_CTRL user return entry,
clear the mask in the found uret MSR instead of vmx->guest_uret_msrs[i].
Modifying guest_uret_msrs directly is completely broken as 'i' does not
point at the MSR_IA32_TSX_CTRL entry. In fact, it's guaranteed to be an
out-of-bounds accesses as is always set to kvm_nr_uret_msrs in a prior
loop. By sheer dumb luck, the fallout is limited to "only" failing to
preserve the host's TSX_CTRL_CPUID_CLEAR. The out-of-bounds access is
benign as it's guaranteed to clear a bit in a guest MSR value, which are
always zero at vCPU creation on both x86-64 and i386.
Cc: stable@vger.kernel.org Fixes: 55e923613be9 ("KVM: VMX: Use common x86's uret MSR list as the one true list") Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210926015545.281083-1-zhenzhong.duan@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Oliver Upton [Fri, 24 Sep 2021 00:51:47 +0000 (00:51 +0000)]
selftests: KVM: Explicitly use movq to read xmm registers
Compiling the KVM selftests with clang emits the following warning:
>> include/x86_64/processor.h:297:25: error: variable 'xmm0' is uninitialized when used here [-Werror,-Wuninitialized]
>> return (unsigned long)xmm0;
where xmm0 is accessed via an uninitialized register variable.
Indeed, this is a misuse of register variables, which really should only
be used for specifying register constraints on variables passed to
inline assembly. Rather than attempting to read xmm registers via
register variables, just explicitly perform the movq from the desired
xmm register.
Fixes: 150755a8b7d8 ("kvm: selftests: add API testing infrastructure") Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20210924005147.1122357-1-oupton@google.com> Reviewed-by: Ricardo Koller <ricarkol@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Oliver Upton [Thu, 23 Sep 2021 22:00:33 +0000 (22:00 +0000)]
selftests: KVM: Call ucall_init when setting up in rseq_test
While x86 does not require any additional setup to use the ucall
infrastructure, arm64 needs to set up the MMIO address used to signal a
ucall to userspace. rseq_test does not initialize the MMIO address,
resulting in the test spinning indefinitely.
Fix the issue by calling ucall_init() during setup.
Fixes: 162ea980739d ("KVM: selftests: Add a test for KVM_RUN+rseq to detect task migration bugs") Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20210923220033.4172362-1-oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Lai Jiangshan [Sat, 18 Sep 2021 00:56:29 +0000 (08:56 +0800)]
KVM: Remove tlbs_dirty
There is no user of tlbs_dirty.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210918005636.3675-4-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Lai Jiangshan [Sat, 18 Sep 2021 00:56:28 +0000 (08:56 +0800)]
KVM: X86: Synchronize the shadow pagetable before link it
If gpte is changed from non-present to present, the guest doesn't need
to flush tlb per SDM. So the host must synchronze sp before
link it. Otherwise the guest might use a wrong mapping.
For example: the guest first changes a level-1 pagetable, and then
links its parent to a new place where the original gpte is non-present.
Finally the guest can access the remapped area without flushing
the tlb. The guest's behavior should be allowed per SDM, but the host
kvm mmu makes it wrong.
Fixes: f77b71643299 ("KVM: MMU: out of sync shadow core") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210918005636.3675-3-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Lai Jiangshan [Sat, 18 Sep 2021 00:56:27 +0000 (08:56 +0800)]
KVM: X86: Fix missed remote tlb flush in rmap_write_protect()
When kvm->tlbs_dirty > 0, some rmaps might have been deleted
without flushing tlb remotely after kvm_sync_page(). If @gfn
was writable before and it's rmaps was deleted in kvm_sync_page(),
and if the tlb entry is still in a remote running VCPU, the @gfn
is not safely protected.
To fix the problem, kvm_sync_page() does the remote flush when
needed to avoid the problem.
Fixes: a5201c6bafef ("KVM: MMU: delay flush all tlbs on sync_page path") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210918005636.3675-2-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These field correspond to features that we don't expose yet to L2
While currently there are no CVE worthy features in this field,
if AMD adds more features to this field, that could allow guest
escapes similar to CVE-2021-3653 and CVE-2021-3656.
KVM: x86: nSVM: test eax for 4K alignment for GP errata workaround
GP SVM errata workaround made the #GP handler always emulate
the SVM instructions.
However these instructions #GP in case the operand is not 4K aligned,
but the workaround code didn't check this and we ended up
emulating these instructions anyway.
This is only an emulation accuracy check bug as there is no harm for
KVM to read/write unaligned vmcb images.
Fixes: 99d9f6552bc0 ("KVM: SVM: Add emulation support for #GP triggered by SVM instructions") Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210914154825.104886-4-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: selftests: test simultaneous uses of V_IRQ from L1 and L0
Test that if:
* L1 disables virtual interrupt masking, and INTR intercept.
* L1 setups a virtual interrupt to be injected to L2 and enters L2 with
interrupts disabled, thus the virtual interrupt is pending.
* Now an external interrupt arrives in L1 and since
L1 doesn't intercept it, it should be delivered to L2 when
it enables interrupts.
to do this L0 (abuses) V_IRQ to setup an
interrupt window, and returns to L2.
* L2 enables interrupts.
This should trigger the interrupt window,
injection of the external interrupt and delivery
of the virtual interrupt that can now be done.
* Test that now L2 gets those interrupts.
This is the test that demonstrates the issue that was
fixed in the previous patch.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210914154825.104886-3-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Intel PMU MSRs is in msrs_to_save_all[], so add AMD PMU MSRs to have a
consistent behavior between Intel and AMD when using KVM_GET_MSRS,
KVM_SET_MSRS or KVM_GET_MSR_INDEX_LIST.
We have to add legacy and new MSRs to handle guests running without
X86_FEATURE_PERFCTR_CORE.
Signed-off-by: Fares Mehanna <faresx@amazon.de>
Message-Id: <20210915133951.22389-1-faresx@amazon.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: nVMX: re-evaluate emulation_required on nested VM exit
If L1 had invalid state on VM entry (can happen on SMM transactions
when we enter from real mode, straight to nested guest),
then after we load 'host' state from VMCS12, the state has to become
valid again, but since we load the segment registers with
__vmx_set_segment we weren't always updating emulation_required.
Update emulation_required explicitly at end of load_vmcs12_host_state.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210913140954.165665-8-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: nVMX: don't fail nested VM entry on invalid guest state if !from_vmentry
It is possible that when non root mode is entered via special entry
(!from_vmentry), that is from SMM or from loading the nested state,
the L2 state could be invalid in regard to non unrestricted guest mode,
but later it can become valid.
(for example when RSM emulation restores segment registers from SMRAM)
Thus delay the check to VM entry, where we will check this and fail.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210913140954.165665-7-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: SVM: call KVM_REQ_GET_NESTED_STATE_PAGES on exit from SMM mode
Currently the KVM_REQ_GET_NESTED_STATE_PAGES on SVM only reloads PDPTRs,
and MSR bitmap, with former not really needed for SMM as SMM exit code
reloads them again from SMRAM'S CR3, and later happens to work
since MSR bitmap isn't modified while in SMM.
Still it is better to be consistient with VMX.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210913140954.165665-5-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: reset pdptrs_from_userspace when exiting smm
When exiting SMM, pdpts are loaded again from the guest memory.
This fixes a theoretical bug, when exit from SMM triggers entry to the
nested guest which re-uses some of the migration
code which uses this flag as a workaround for a legacy userspace.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210913140954.165665-4-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: nVMX: Filter out all unsupported controls when eVMCS was activated
Windows Server 2022 with Hyper-V role enabled failed to boot on KVM when
enlightened VMCS is advertised. Debugging revealed there are two exposed
secondary controls it is not happy with: SECONDARY_EXEC_ENABLE_VMFUNC and
SECONDARY_EXEC_SHADOW_VMCS. These controls are known to be unsupported,
as there are no corresponding fields in eVMCSv1 (see the comment above
EVMCS1_UNSUPPORTED_2NDEXEC definition).
Previously, commit f946e45b3bf1 ("x86/kvm/hyper-v: move VMX controls
sanitization out of nested_enable_evmcs()") introduced the required
filtering mechanism for VMX MSRs but for some reason put only known
to be problematic (and not full EVMCS1_UNSUPPORTED_* lists) controls
there.
Note, Windows Server 2022 seems to have gained some sanity check for VMX
MSRs: it doesn't even try to launch a guest when there's something it
doesn't like, nested_evmcs_check_controls() mechanism can't catch the
problem.
Let's be bold this time and instead of playing whack-a-mole just filter out
all unsupported controls from VMX MSRs.
Fixes: f946e45b3bf1 ("x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210907163530.110066-1-vkuznets@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: KVM: Use cpumask_available() to check for NULL cpumask when kicking vCPUs
Check for a NULL cpumask_var_t when kicking multiple vCPUs via
cpumask_available(), which performs a !NULL check if and only if cpumasks
are configured to be allocated off-stack. This is a meaningless
optimization, e.g. avoids a TEST+Jcc and TEST+CMOV on x86, but more
importantly helps document that the NULL check is necessary even though
all callers pass in a local variable.
No functional change intended.
Cc: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210827092516.1027264-3-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: Clean up benign vcpu->cpu data races when kicking vCPUs
Fix a benign data race reported by syzbot+KCSAN[*] by ensuring vcpu->cpu
is read exactly once, and by ensuring the vCPU is booted from guest mode
if kvm_arch_vcpu_should_kick() returns true. Fix a similar race in
kvm_make_vcpus_request_mask() by ensuring the vCPU is interrupted if
kvm_request_needs_ipi() returns true.
Reading vcpu->cpu before vcpu->mode (via kvm_arch_vcpu_should_kick() or
kvm_request_needs_ipi()) means the target vCPU could get migrated (change
vcpu->cpu) and enter !OUTSIDE_GUEST_MODE between reading vcpu->cpud and
reading vcpu->mode. If that happens, the kick/IPI will be sent to the
old pCPU, not the new pCPU that is now running the vCPU or reading SPTEs.
Although failing to kick the vCPU is not exactly ideal, practically
speaking it cannot cause a functional issue unless there is also a bug in
the caller, and any such bug would exist regardless of kvm_vcpu_kick()'s
behavior.
The purpose of sending an IPI is purely to get a vCPU into the host (or
out of reading SPTEs) so that the vCPU can recognize a change in state,
e.g. a KVM_REQ_* request. If vCPU's handling of the state change is
required for correctness, KVM must ensure either the vCPU sees the change
before entering the guest, or that the sender sees the vCPU as running in
guest mode. All architectures handle this by (a) sending the request
before calling kvm_vcpu_kick() and (b) checking for requests _after_
setting vcpu->mode.
x86's READING_SHADOW_PAGE_TABLES has similar requirements; KVM needs to
ensure it kicks and waits for vCPUs that started reading SPTEs _before_
MMU changes were finalized, but any vCPU that starts reading after MMU
changes were finalized will see the new state and can continue on
uninterrupted.
For uses of kvm_vcpu_kick() that are not paired with a KVM_REQ_*, e.g.
x86's kvm_arch_sync_dirty_log(), the order of the kick must not be relied
upon for functional correctness, e.g. in the dirty log case, userspace
cannot assume it has a 100% complete log if vCPUs are still running.
All that said, eliminate the benign race since the cost of doing so is an
"extra" atomic cmpxchg() in the case where the target vCPU is loaded by
the current pCPU or is not loaded at all. I.e. the kick will be skipped
due to kvm_vcpu_exiting_guest_mode() seeing a compatible vcpu->mode as
opposed to the kick being skipped because of the cpu checks.
Keep the "cpu != me" checks even though they appear useless/impossible at
first glance. x86 processes guest IPI writes in a fast path that runs in
IN_GUEST_MODE, i.e. can call kvm_vcpu_kick() from IN_GUEST_MODE. And
calling kvm_vm_bugged()->kvm_make_vcpus_request_mask() from IN_GUEST or
READING_SHADOW_PAGE_TABLES is perfectly reasonable.
Note, a race with the cpu_online() check in kvm_vcpu_kick() likely
persists, e.g. the vCPU could exit guest mode and get offlined between
the cpu_online() check and the sending of smp_send_reschedule(). But,
the online check appears to exist only to avoid a WARN in x86's
native_smp_send_reschedule() that fires if the target CPU is not online.
The reschedule WARN exists because CPU offlining takes the CPU out of the
scheduling pool, i.e. the WARN is intended to detect the case where the
kernel attempts to schedule a task on an offline CPU. The actual sending
of the IPI is a non-issue as at worst it will simpy be dropped on the
floor. In other words, KVM's usurping of the reschedule IPI could
theoretically trigger a WARN if the stars align, but there will be no
loss of functionality.
The problem appears to be that 'vcpu_bitmap' is allocated as a single long
on stack and it should really be KVM_MAX_VCPUS long. We also seem to clear
the lower 16 bits of it with bitmap_zero() for no particular reason (my
guess would be that 'bitmap' and 'vcpu_bitmap' variables in
kvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed
16-bit long, the later should accommodate all possible vCPUs).
Fixes: 8b921683d239 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs") Fixes: 7eb9a980acfc ("KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap") Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210827092516.1027264-7-vkuznets@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
David Matlack [Fri, 17 Sep 2021 17:36:57 +0000 (17:36 +0000)]
KVM: selftests: Create a separate dirty bitmap per slot
The calculation to get the per-slot dirty bitmap was incorrect leading
to a buffer overrun. Fix it by splitting out the dirty bitmap into a
separate bitmap per slot.
Fixes: 33e51d157dba ("KVM: selftests: Support multiple slots in dirty_log_perf_test") Signed-off-by: David Matlack <dmatlack@google.com> Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20210917173657.44011-4-dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
David Matlack [Fri, 17 Sep 2021 17:36:56 +0000 (17:36 +0000)]
KVM: selftests: Refactor help message for -s backing_src
All selftests that support the backing_src option were printing their
own description of the flag and then calling backing_src_help() to dump
the list of available backing sources. Consolidate the flag printing in
backing_src_help() to align indentation, reduce duplicated strings, and
improve consistency across tests.
Note: Passing "-s" to backing_src_help is unnecessary since every test
uses the same flag. However I decided to keep it for code readability
at the call sites.
While here this opportunistically fixes the incorrectly interleaved
printing -x help message and list of backing source types in
dirty_log_perf_test.
Fixes: 33e51d157dba ("KVM: selftests: Support multiple slots in dirty_log_perf_test") Reviewed-by: Ben Gardon <bgardon@google.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210917173657.44011-3-dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
David Matlack [Fri, 17 Sep 2021 17:36:55 +0000 (17:36 +0000)]
KVM: selftests: Change backing_src flag to -s in demand_paging_test
Every other KVM selftest uses -s for the backing_src, so switch
demand_paging_test to match.
Reviewed-by: Ben Gardon <bgardon@google.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210917173657.44011-2-dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Peter Gonda [Tue, 21 Sep 2021 15:03:45 +0000 (08:03 -0700)]
KVM: SEV: Allow some commands for mirror VM
A mirrored SEV-ES VM will need to call KVM_SEV_LAUNCH_UPDATE_VMSA to
setup its vCPUs and have them measured, and their VMSAs encrypted. Without
this change, it is impossible to have mirror VMs as part of SEV-ES VMs.
Also allow the guest status check and debugging commands since they do
not change any guest state.
Signed-off-by: Peter Gonda <pgonda@google.com> Cc: Marc Orr <marcorr@google.com> Cc: Nathan Tempelman <natet@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steve Rutherford <srutherford@google.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 90d0c700aaf0 ("KVM: x86: Support KVM VMs sharing SEV context", 2021-04-21)
Message-Id: <20210921150345.2221634-3-pgonda@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Peter Gonda [Tue, 21 Sep 2021 15:03:44 +0000 (08:03 -0700)]
KVM: SEV: Update svm_vm_copy_asid_from for SEV-ES
For mirroring SEV-ES the mirror VM will need more then just the ASID.
The FD and the handle are required to all the mirror to call psp
commands. The mirror VM will need to call KVM_SEV_LAUNCH_UPDATE_VMSA to
setup its vCPUs' VMSAs for SEV-ES.
Signed-off-by: Peter Gonda <pgonda@google.com> Cc: Marc Orr <marcorr@google.com> Cc: Nathan Tempelman <natet@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steve Rutherford <srutherford@google.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 90d0c700aaf0 ("KVM: x86: Support KVM VMs sharing SEV context", 2021-04-21)
Message-Id: <20210921150345.2221634-2-pgonda@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nested bus lock VM exits are not supported yet. If L2 triggers bus lock
VM exit, it will be directed to L1 VMM, which would cause unexpected
behavior. Therefore, handle L2's bus lock VM exits in L0 directly.
Fixes: f79dabbd7827 ("KVM: VMX: Enable bus lock VM exit") Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20210914095041.29764-1-chenyi.qiang@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Identify vCPU0 by its vcpu_idx instead of its vCPUs array entry
Use vcpu_idx to identify vCPU0 when updating HyperV's TSC page, which is
shared by all vCPUs and "owned" by vCPU0 (because vCPU0 is the only vCPU
that's guaranteed to exist). Using kvm_get_vcpu() to find vCPU works,
but it's a rather odd and suboptimal method to check the index of a given
vCPU.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210910183220.2397812-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Query vcpu->vcpu_idx directly and drop its accessor
Read vcpu->vcpu_idx directly instead of bouncing through the one-line
wrapper, kvm_vcpu_get_idx(), and drop the wrapper. The wrapper is a
remnant of the original implementation and serves no purpose; remove it
before it gains more users.
Back when kvm_vcpu_get_idx() was added by commit 4e1b31ba5187 ("KVM: Add
kvm_vcpu_get_idx to get vcpu index in kvm->vcpus"), the implementation
was more than just a simple wrapper as vcpu->vcpu_idx did not exist and
retrieving the index meant walking over the vCPU array to find the given
vCPU.
When vcpu_idx was introduced by commit 3bce264c3fa4 ("KVM: remember
position in kvm->vcpus array"), the helper was left behind, likely to
avoid extra thrash (but even then there were only two users, the original
arm usage having been removed at some point in the past).
KVM: SVM: fix missing sev_decommission in sev_receive_start
DECOMMISSION the current SEV context if binding an ASID fails after
RECEIVE_START. Per AMD's SEV API, RECEIVE_START generates a new guest
context and thus needs to be paired with DECOMMISSION:
The RECEIVE_START command is the only command other than the LAUNCH_START
command that generates a new guest context and guest handle.
The missing DECOMMISSION can result in subsequent SEV launch failures,
as the firmware leaks memory and might not able to allocate more SEV
guest contexts in the future.
Note, LAUNCH_START suffered the same bug, but was previously fixed by
commit e1d30bb0fe9f ("KVM: SVM: Call SEV Guest Decommission if ASID
binding fails").
Cc: Alper Gun <alpergun@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: David Rienjes <rientjes@google.com> Cc: Marc Orr <marcorr@google.com> Cc: John Allen <john.allen@amd.com> Cc: Peter Gonda <pgonda@google.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Vipin Sharma <vipinsh@google.com> Cc: stable@vger.kernel.org Reviewed-by: Marc Orr <marcorr@google.com> Acked-by: Brijesh Singh <brijesh.singh@amd.com> Fixes: 53a263e73751 ("KVM: SVM: Add support for KVM_SEV_RECEIVE_START command") Signed-off-by: Mingwei Zhang <mizhang@google.com> Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210912181815.3899316-1-mizhang@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Peter Gonda [Wed, 15 Sep 2021 17:17:55 +0000 (10:17 -0700)]
KVM: SEV: Acquire vcpu mutex when updating VMSA
The update-VMSA ioctl touches data stored in struct kvm_vcpu, and
therefore should not be performed concurrently with any VCPU ioctl
that might cause KVM or the processor to use the same data.
Adds vcpu mutex guard to the VMSA updating code. Refactors out
__sev_launch_update_vmsa() function to deal with per vCPU parts
of sev_launch_update_vmsa().
Fixes: af0c2261c7b3 ("KVM: SVM: Provide support to launch and run an SEV-ES guest") Signed-off-by: Peter Gonda <pgonda@google.com> Cc: Marc Orr <marcorr@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org
Message-Id: <20210915171755.3773766-1-pgonda@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
grow_halt_poll_ns() ignores values between 0 and
halt_poll_ns_grow_start (10000 by default). However,
when we shrink halt_poll_ns we may fall way below
halt_poll_ns_grow_start and endup with halt_poll_ns
values that don't make a lot of sense: like 1 or 9,
or 19.
"VMXON pointer" is saved in vmx->nested.vmxon_ptr since
commit c9ccb14eae60 ("KVM: nVMX: additional checks on
vmxon region"). Also, handle_vmptrld() & handle_vmclear()
now have logic to check the VMCS pointer against the VMXON
pointer.
So just remove the obsolete comments of handle_vmon().
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Message-Id: <20210908171731.18885-1-yu.c.zhang@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Handle SRCU initialization failure during page track init
Check the return of init_srcu_struct(), which can fail due to OOM, when
initializing the page track mechanism. Lack of checking leads to a NULL
pointer deref found by a modified syzkaller.
Reported-by: TCS Robot <tcs_robot@tencent.com> Signed-off-by: Haimin Zhang <tcs_kernel@tencent.com>
Message-Id: <1630636626-12262-1-git-send-email-tcs_kernel@tencent.com>
[Move the call towards the beginning of kvm_arch_init_vm. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: VMX: Remove defunct "nr_active_uret_msrs" field
Remove vcpu_vmx.nr_active_uret_msrs and its associated comment, which are
both defunct now that KVM keeps the list constant and instead explicitly
tracks which entries need to be loaded into hardware.
No functional change intended.
Fixes: 0cbfa920a383 ("KVM: VMX: Use flag to indicate "active" uret MSRs instead of sorting list") Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210908002401.1947049-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Oliver Upton [Tue, 21 Sep 2021 17:11:21 +0000 (17:11 +0000)]
selftests: KVM: Align SMCCC call with the spec in steal_time
The SMC64 calling convention passes a function identifier in w0 and its
parameters in x1-x17. Given this, there are two deviations in the
SMC64 call performed by the steal_time test: the function identifier is
assigned to a 64 bit register and the parameter is only 32 bits wide.
Align the call with the SMCCC by using a 32 bit register to handle the
function identifier and increasing the parameter width to 64 bits.
Suggested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Oliver Upton <oupton@google.com> Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20210921171121.2148982-3-oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Oliver Upton [Tue, 21 Sep 2021 17:11:20 +0000 (17:11 +0000)]
selftests: KVM: Fix check for !POLLIN in demand_paging_test
The logical not operator applies only to the left hand side of a bitwise
operator. As such, the check for POLLIN not being set in revents wrong.
Fix it by adding parentheses around the bitwise expression.
Fixes: e4ff92617a06 ("KVM: selftests: Add demand paging content to the demand paging test") Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20210921171121.2148982-2-oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Clear KVM's cached guest CR3 at RESET/INIT
Explicitly zero the guest's CR3 and mark it available+dirty at RESET/INIT.
Per Intel's SDM and AMD's APM, CR3 is zeroed at both RESET and INIT. For
RESET, this is a nop as vcpu is zero-allocated. For INIT, the bug has
likely escaped notice because no firmware/kernel puts its page tables root
at PA=0, let alone relies on INIT to get the desired CR3 for such page
tables.
Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210921000303.400537-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Mark all registers as avail/dirty at vCPU creation
Mark all registers as available and dirty at vCPU creation, as the vCPU has
obviously not been loaded into hardware, let alone been given the chance to
be modified in hardware. On SVM, reading from "uninitialized" hardware is
a non-issue as VMCBs are zero allocated (thus not truly uninitialized) and
hardware does not allow for arbitrary field encoding schemes.
On VMX, backing memory for VMCSes is also zero allocated, but true
initialization of the VMCS _technically_ requires VMWRITEs, as the VMX
architectural specification technically allows CPU implementations to
encode fields with arbitrary schemes. E.g. a CPU could theoretically store
the inverted value of every field, which would result in VMREAD to a
zero-allocated field returns all ones.
In practice, only the AR_BYTES fields are known to be manipulated by
hardware during VMREAD/VMREAD; no known hardware or VMM (for nested VMX)
does fancy encoding of cacheable field values (CR0, CR3, CR4, etc...). In
other words, this is technically a bug fix, but practically speakings it's
a glorified nop.
Failure to mark registers as available has been a lurking bug for quite
some time. The original register caching supported only GPRs (+RIP, which
is kinda sorta a GPR), with the masks initialized at ->vcpu_reset(). That
worked because the two cacheable registers, RIP and RSP, are generally
speaking not read as side effects in other flows.
Arguably, commit ebebf0744702 ("KVM: Fetch guest cr3 from hardware on
demand") was the first instance of failure to mark regs available. While
_just_ marking CR3 available during vCPU creation wouldn't have fixed the
VMREAD from an uninitialized VMCS bug because ept_update_paging_mode_cr0()
unconditionally read vmcs.GUEST_CR3, marking CR3 _and_ intentionally not
reading GUEST_CR3 when it's available would have avoided VMREAD to a
technically-uninitialized VMCS.
Fixes: ebebf0744702 ("KVM: Fetch guest cr3 from hardware on demand") Fixes: d1b4ffa65829 ("KVM: Cache pdptrs") Fixes: f0c59ce9c100 ("KVM: VMX: Optimize vmx_get_rflags()") Fixes: 0f6052e4735f ("KVM: VMX: Cache vmcs segment fields") Fixes: d295c68065dd ("KVM: VMX: Add proper cache tracking for CR0") Fixes: cc67afbf9f8d ("KVM: VMX: Add proper cache tracking for CR4") Fixes: 712524f469cf ("KVM: VMX: Cache vmcs.EXIT_QUALIFICATION using arch avail_reg flags") Fixes: 4df01047ae13 ("KVM: VMX: Cache vmcs.EXIT_INTR_INFO using arch avail_reg flags") Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210921000303.400537-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Revert the __NR_userfaultfd syscall fallback added for KVM selftests now
that x86's unistd_{32,63}.h overrides are under uapi/ and thus not in
KVM selftests' search path, i.e. now that KVM gets x86 syscall numbers
from the installed kernel headers.
No functional change intended.
Reviewed-by: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210901203030.1292304-6-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: selftests: Add a test for KVM_RUN+rseq to detect task migration bugs
Add a test to verify an rseq's CPU ID is updated correctly if the task is
migrated while the kernel is handling KVM_RUN. This is a regression test
for a bug introduced by commit e50b70b37325 ("x86/kvm: Use generic xfer
to guest work function"), where TIF_NOTIFY_RESUME would be cleared by KVM
without updating rseq, leading to a stale CPU ID and other badness.
Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Message-Id: <20210901203030.1292304-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
tools: Move x86 syscall number fallbacks to .../uapi/
Move unistd_{32,64}.h from x86/include/asm to x86/include/uapi/asm so
that tools/selftests that install kernel headers, e.g. KVM selftests, can
include non-uapi tools headers, e.g. to get 'struct list_head', without
effectively overriding the installed non-tool uapi headers.
Swapping KVM's search order, e.g. to search the kernel headers before
tool headers, is not a viable option as doing results in linux/type.h and
other core headers getting pulled from the kernel headers, which do not
have the kernel-internal typedefs that are used through tools, including
many files outside of selftests/kvm's control.
Prior to commit c4e924e6d6c4 ("perf tools: Move syscall number fallbacks
from perf-sys.h to tools/arch/x86/include/asm/"), the handcoded numbers
were actual fallbacks, i.e. overriding unistd_{32,64}.h from the kernel
headers was unintentional.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210901203030.1292304-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume()
Invoke rseq_handle_notify_resume() from tracehook_notify_resume() now
that the two function are always called back-to-back by architectures
that have rseq. The rseq helper is stubbed out for architectures that
don't support rseq, i.e. this is a nop across the board.
Note, tracehook_notify_resume() is horribly named and arguably does not
belong in tracehook.h as literally every line of code in it has nothing
to do with tracing. But, that's been true since commit 82589b1eab4c
("move key_repace_session_keyring() into tracehook_notify_resume()")
first usurped tracehook_notify_resume() back in 2012. Punt cleaning that
mess up to future patches.
No functional change intended.
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210901203030.1292304-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: rseq: Update rseq when processing NOTIFY_RESUME on xfer to KVM guest
Invoke rseq's NOTIFY_RESUME handler when processing the flag prior to
transferring to a KVM guest, which is roughly equivalent to an exit to
userspace and processes many of the same pending actions. While the task
cannot be in an rseq critical section as the KVM path is reachable only
by via ioctl(KVM_RUN), the side effects that apply to rseq outside of a
critical section still apply, e.g. the current CPU needs to be updated if
the task is migrated.
Clearing TIF_NOTIFY_RESUME without informing rseq can lead to segfaults
and other badness in userspace VMMs that use rseq in combination with KVM,
e.g. due to the CPU ID being stale after task migration.
Fixes: e50b70b37325 ("x86/kvm: Use generic xfer to guest work function") Reported-by: Peter Foley <pefoley@google.com> Bisected-by: Doug Evans <dje@google.com> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210901203030.1292304-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Marc Zyngier [Sun, 19 Sep 2021 13:09:49 +0000 (14:09 +0100)]
KVM: arm64: Fix PMU probe ordering
Russell reported that since 5.13, KVM's probing of the PMU has
started to fail on his HW. As it turns out, there is an implicit
ordering dependency between the architectural PMU probing code and
and KVM's own probing. If, due to probe ordering reasons, KVM probes
before the PMU driver, it will fail to detect the PMU and prevent it
from being advertised to guests as well as the VMM.
Obviously, this is one probing too many, and we should be able to
deal with any ordering.
Add a callback from the PMU code into KVM to advertise the registration
of a host CPU PMU, allowing for any probing order.
Fixes: 346fe85f2b61 ("KVM: arm64: Divorce the perf code from oprofile helpers") Reported-by: "Russell King (Oracle)" <linux@armlinux.org.uk> Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/YUYRKVflRtUytzy5@shell.armlinux.org.uk Cc: stable@vger.kernel.org
pci_iounmap'2: Electric Boogaloo: try to make sense of it all
Nathan Chancellor reports that the recent change to pci_iounmap in
commit 1b1b69464a26 ("parisc: Declare pci_iounmap() parisc version only
when CONFIG_PCI enabled") causes build errors on arm64.
It took me about two hours to convince myself that I think I know what
the logic of that mess of #ifdef's in the <asm-generic/io.h> header file
really aim to do, and rewrite it to be easier to follow.
Famous last words.
Anyway, the code has now been lifted from that grotty header file into
lib/pci_iomap.c, and has fairly extensive comments about what the logic
is. It also avoids indirecting through another confusing (and badly
named) helper function that has other preprocessor config conditionals.
Let's see what odd architecture did something else strange in this area
to break things. But my arm64 cross build is clean.
Fixes: 1b1b69464a26 ("parisc: Declare pci_iounmap() parisc version only when CONFIG_PCI enabled") Reported-by: Nathan Chancellor <nathan@kernel.org> Cc: Helge Deller <deller@gmx.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Ulrich Teichert <krypton@ulrich-teichert.org> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'x86_urgent_for_v5.15_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- Prevent a infinite loop in the MCE recovery on return to user space,
which was caused by a second MCE queueing work for the same page and
thereby creating a circular work list.
- Make kern_addr_valid() handle existing PMD entries, which are marked
not present in the higher level page table, correctly instead of
blindly dereferencing them.
- Pass a valid address to sanitize_phys(). This was caused by the
mixture of inclusive and exclusive ranges. memtype_reserve() expect
'end' being exclusive, but sanitize_phys() wants it inclusive. This
worked so far, but with end being the end of the physical address
space the fail is exposed.
- Increase the maximum supported GPIO numbers for 64bit. Newer SoCs
exceed the previous maximum.
* tag 'x86_urgent_for_v5.15_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Avoid infinite loop for copy from user recovery
x86/mm: Fix kern_addr_valid() to cope with existing but not present entries
x86/platform: Increase maximum GPIO number for X86_64
x86/pat: Pass valid address to sanitize_phys()
Merge tag 'perf-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf event fix from Thomas Gleixner:
"A single fix for the perf core where a value read with READ_ONCE() was
checked and then reread which makes all the checks invalid. Reuse the
already read value instead"
* tag 'perf-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
events: Reuse value read using READ_ONCE instead of re-reading it
Merge tag 'locking-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Thomas Gleixner:
"A set of updates for the RT specific reader/writer locking base code:
- Make the fast path reader ordering guarantees correct.
- Code reshuffling to make the fix simpler"
[ This plays ugly games with atomic_add_return_release() because we
don't have a plain atomic_add_release(), and should really be cleaned
up, I think - Linus ]
* tag 'locking-urgent-2021-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rwbase: Take care of ordering guarantee for fastpath reader
locking/rwbase: Extract __rwbase_write_trylock()
locking/rwbase: Properly match set_and_save_state() to restore_state()
Merge tag 'powerpc-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Fix crashes when scv (System Call Vectored) is used to make a syscall
when a transaction is active, on Power9 or later.
- Fix bad interactions between rfscv (Return-from scv) and Power9
fake-suspend mode.
- Fix crashes when handling machine checks in LPARs using the Hash MMU.
- Partly revert a recent change to our XICS interrupt controller code,
which broke the recently added Microwatt support.
Thanks to Cédric Le Goater, Eirik Fuller, Ganesh Goudar, Gustavo Romero,
Joel Stanley, Nicholas Piggin.
* tag 'powerpc-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/xics: Set the IRQ chip data for the ICS native backend
powerpc/mce: Fix access error in mce handler
KVM: PPC: Book3S HV: Tolerate treclaim. in fake-suspend mode changing registers
powerpc/64s: system call rfscv workaround for TM bugs
selftests/powerpc: Add scv versions of the basic TM syscall tests
powerpc/64s: system call scv tabort fix for corrupt irq soft-mask state
Merge tag 'kbuild-fixes-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- Fix bugs in checkkconfigsymbols.py
- Fix missing sys import in gen_compile_commands.py
- Fix missing FORCE warning for ARCH=sh builds
- Fix -Wignored-optimization-argument warnings for Clang builds
- Turn -Wignored-optimization-argument into an error in order to stop
building instead of sprinkling warnings
* tag 'kbuild-fixes-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: Add -Werror=ignored-optimization-argument to CLANG_FLAGS
x86/build: Do not add -falign flags unconditionally for clang
kbuild: Fix comment typo in scripts/Makefile.modpost
sh: Add missing FORCE prerequisites in Makefile
gen_compile_commands: fix missing 'sys' package
checkkconfigsymbols.py: Remove skipping of help lines in parse_kconfig_file
checkkconfigsymbols.py: Forbid passing 'HEAD' to --commit
Merge tag 'perf-tools-fixes-for-v5.15-2021-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix ip display in 'perf script' when output type != attr->type.
- Ignore deprecation warning when using libbpf'sg btf__get_from_id(),
fixing the build with libbpf v0.6+.
- Make use of FD() robust in libperf, fixing a segfault with 'perf stat
--iostat list'.
- Initialize addr_location:srcline pointer to NULL when resolving
callchain addresses.
- Fix fused instruction logic for assembly functions in 'perf
annotate'.
* tag 'perf-tools-fixes-for-v5.15-2021-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf bpf: Ignore deprecation warning when using libbpf's btf__get_from_id()
libperf evsel: Make use of FD robust.
perf machine: Initialize srcline string member in add_location struct
perf script: Fix ip display when type != attr->type
perf annotate: Fix fused instr logic for assembly functions
dmascc: use proper 'virt_to_bus()' rather than casting to 'int'
The old dmascc driver depends on the legacy ISA_DMA_API, and blindly
just casts the kernel virtual address to 'int' for set_dma_addr().
That works only incidentally, and because the high bits of the address
will be ignored anyway. And on 64-bit architectures it causes warnings.
Admittedly, 64-bit architectures with ISA are basically dead - I think
the only example of this is alpha, and nobody would ever use the dmascc
driver there. But hey, the fix is easy enough, the end result is
cleaner, and it's yet another configuration that now builds without
warnings.
If somebody actually uses this driver on an alpha and this fixes it for
you, please email me. Because that is just incredibly bizarre.
With the previous commit (1b1b69464a26: "parisc: Declare pci_iounmap()
parisc version only when CONFIG_PCI enabled") we can now enable
GENERIC_PCI_IOMAP unconditionally on alpha, and if PCI is not enabled we
will just get the nice empty helper functions that allow mixed-bus
drivers to build.
Example driver: the old 3com/3c59x.c driver works with either the PCI or
the EISA version of the 3x59x card, but wouldn't build in an EISA-only
configuration because of missing pci_iomap() and pci_iounmap() dummy
wrappers.
Most of the other PCI infrastructure just becomes empty wrappers even
without GENERIC_PCI_IOMAP, and it's not obvious that the pci_iomap
functionality shouldn't do the same, but this works.
parisc: Declare pci_iounmap() parisc version only when CONFIG_PCI enabled
Linus noticed odd declaration rules for pci_iounmap() in iomap.h and
pci_iomap.h, where it dependend on either NO_GENERIC_PCI_IOPORT_MAP or
GENERIC_IOMAP when CONFIG_PCI was disabled.
Testing on parisc seems to indicate that we need pci_iounmap() only when
CONFIG_PCI is enabled, so the declaration of pci_iounmap() can be moved
cleanly into pci_iomap.h in sync with the declarations of pci_iomap().
Sudip Mukherjee reports that this broke pulseaudio with a NULL pointer
dereference in vc4_hdmi_audio_prepare(), bisected it to this commit, and
confirmed that a revert fixed the problem.
2fc59b879d73 ("drm/vc4: hdmi: Make sure the controller is powered in detect") 7460d0fdf66b ("drm/vc4: hdmi: Move the HSM clock enable to runtime_pm")
as Michael Stapelberg reports that the new runtime PM changes cause his
Raspberry Pi 3 to hang on boot, probably due to interactions with other
changes in the DRM tree (because a bisect points to the merge in commit 6e3215a56709: "Merge tag 'drm-next-2021-07-01' of git://.../drm").
Revert these two commits until it's been resolved.
kbuild: Add -Werror=ignored-optimization-argument to CLANG_FLAGS
Similar to commit 8c585b8df2d2 ("kbuild: Add
-Werror=unknown-warning-option to CLANG_FLAGS").
Clang ignores certain GCC flags that it has not implemented, only
emitting a warning:
$ echo | clang -fsyntax-only -falign-jumps -x c -
clang-14: warning: optimization flag '-falign-jumps' is not supported
[-Wignored-optimization-argument]
When one of these flags gets added to KBUILD_CFLAGS unconditionally, all
subsequent cc-{disable-warning,option} calls fail because -Werror was
added to these invocations to turn the above warning and the equivalent
-W flag warning into errors.
To catch the presence of these flags earlier, turn
-Wignored-optimization-argument into an error so that the flags can
either be implemented or ignored via cc-option and there are no more
weird errors.
x86/build: Do not add -falign flags unconditionally for clang
clang does not support -falign-jumps and only recently gained support
for -falign-loops. When one of the configuration options that adds these
flags is enabled, clang warns and all cc-{disable-warning,option} that
follow fail because -Werror gets added to test for the presence of this
warning:
clang-14: warning: optimization flag '-falign-jumps=0' is not supported
[-Wignored-optimization-argument]
To resolve this, add a couple of cc-option calls when building with
clang; gcc has supported these options since 3.2 so there is no point in
testing for their support. -falign-functions was implemented in clang-7,
-falign-loops was implemented in clang-14, and -falign-jumps has not
been implemented yet.
arch/sh/boot/Makefile:87: FORCE prerequisite is missing
Add the missing FORCE prerequisites for all build targets identified by
"make help".
Fixes: df71cd8b301565cb ("kbuild: warn if FORCE is missing for if_changed(_dep,_rule) and filechk") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
checkkconfigsymbols.py: Remove skipping of help lines in parse_kconfig_file
When parsing Kconfig files to find symbol definitions and references,
lines after a 'help' line are skipped until a new config definition
starts.
However, Kconfig statements can actually be after a help section, as
long as these have shallower indentation. These are skipped by the
parser.
This means that symbols referenced in this kind of statements are
ignored by this function and thus are not considered undefined
references in case the symbol is not defined.
Remove the 'skip' logic entirely, as it is not needed if we just use the
STMT regex to find the end of help lines.
However, this means that keywords that appear as part of the help
message (i.e. with the same indentation as the help lines) it will be
considered as a reference/definition. This can happen now as well, but
only with REGEX_KCONFIG_DEF lines. Also, the keyword must have a SYMBOL
after it, which probably means that someone referenced a config in the
help so it seems like a bonus :)
The real solution is to keep track of the indentation when a the first
help line in encountered and then handle DEF and STMT lines only if the
indentation is shallower.
checkkconfigsymbols.py: Forbid passing 'HEAD' to --commit
As opposed to the --diff option, --commit can get ref names instead of
commit hashes.
When using the --commit option, the script resets the working directory
to the commit before the given ref, by adding '~' to the end of the ref.
However, the 'HEAD' ref is relative, and so when the working directory
is reset to 'HEAD~', 'HEAD' points to what was 'HEAD~'. Then when the
script resets to 'HEAD' it actually stays in the same commit. In this
case, the script won't report any cases because there is no diff between
the cases of the two refs.
Prevent the user from using HEAD refs.
A better solution might be to resolve the refs before doing the
reset, but for now just disallow such refs.
alpha: move __udiv_qrnnd library function to arch/alpha/lib/
We already had the implementation for __udiv_qrnnd (unsigned divide for
multi-precision arithmetic) as part of the alpha math emulation code.
But you can disable the math emulation code - even if you shouldn't -
and then the MPI code that actually wants this functionality (and is
needed by various crypto functions) will fail to build.
So move the extended-precision divide code to be a regular library
function, just like all the regular division code is. That way ie is
available regardless of math-emulation.
Ok, it almost certainly is still broken on actual hardware, but the
immediate reason for it having been marked BROKEN was a build error that
is fixed by just making sure the low-level IO header file is included
sufficiently early that the __EXTERN_INLINE hackery takes effect.
This was marked broken back in 2017 by commit 9dabf17959f4 ("alpha: mark
jensen as broken"), but Ulrich Teichert made me look at it as part of my
cross-build work to make sure -Werror actually does the right thing.
There are lots of alpha configurations that do not build cleanly, but
now it's no longer because Jensen wouldn't be buildable. That said,
because the Jensen platform doesn't force PCI to be enabled (Jensen only
had EISA), it ends up being somewhat interesting as a source of odd
configs.
perf bpf: Ignore deprecation warning when using libbpf's btf__get_from_id()
Perf code re-implements libbpf's btf__load_from_kernel_by_id() API as
a weak function, presumably to dynamically link against old version of
libbpf shared library. Unfortunately this causes compilation warning
when perf is compiled against libbpf v0.6+.
For now, just ignore deprecation warning, but there might be a better
solution, depending on perf's needs.
Ian Rogers [Sat, 18 Sep 2021 05:44:40 +0000 (22:44 -0700)]
libperf evsel: Make use of FD robust.
FD uses xyarray__entry that may return NULL if an index is out of
bounds. If NULL is returned then a segv happens as FD unconditionally
dereferences the pointer. This was happening in a case of with perf
iostat as shown below. The fix is to make FD an "int*" rather than an
int and handle the NULL case as either invalid input or a closed fd.
$ sudo gdb --args perf stat --iostat list
...
Breakpoint 1, perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
50 {
(gdb) bt
#0 perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
#1 0x000055555585c188 in evsel__open_cpu (evsel=0x5555560951a0, cpus=0x555556093410,
threads=0x555556086fb0, start_cpu=0, end_cpu=1) at util/evsel.c:1792
#2 0x000055555585cfb2 in evsel__open (evsel=0x5555560951a0, cpus=0x0, threads=0x555556086fb0)
at util/evsel.c:2045
#3 0x000055555585d0db in evsel__open_per_thread (evsel=0x5555560951a0, threads=0x555556086fb0)
at util/evsel.c:2065
#4 0x00005555558ece64 in create_perf_stat_counter (evsel=0x5555560951a0,
config=0x555555c34700 <stat_config>, target=0x555555c2f1c0 <target>, cpu=0) at util/stat.c:590
#5 0x000055555578e927 in __run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
at builtin-stat.c:833
#6 0x000055555578f3c6 in run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
at builtin-stat.c:1048
#7 0x0000555555792ee5 in cmd_stat (argc=1, argv=0x7fffffffe4a0) at builtin-stat.c:2534
#8 0x0000555555835ed3 in run_builtin (p=0x555555c3f540 <commands+288>, argc=3,
argv=0x7fffffffe4a0) at perf.c:313
#9 0x0000555555836154 in handle_internal_command (argc=3, argv=0x7fffffffe4a0) at perf.c:365
#10 0x000055555583629f in run_argv (argcp=0x7fffffffe2ec, argv=0x7fffffffe2e0) at perf.c:409
#11 0x0000555555836692 in main (argc=3, argv=0x7fffffffe4a0) at perf.c:539
...
(gdb) c
Continuing.
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_iio_0/event=0x83,umask=0x04,ch_mask=0xF,fc_mask=0x07/).
/bin/dmesg | grep -i perf may provide additional information.
Program received signal SIGSEGV, Segmentation fault.
0x00005555559b03ea in perf_evsel__close_fd_cpu (evsel=0x5555560951a0, cpu=1) at evsel.c:166
166 if (FD(evsel, cpu, thread) >= 0)
v3. fixes a bug in perf_evsel__run_ioctl where the sense of a branch was
backward.
Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20210918054440.2350466-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Michael Petlan [Mon, 19 Jul 2021 14:53:32 +0000 (16:53 +0200)]
perf machine: Initialize srcline string member in add_location struct
It's later supposed to be either a correct address or NULL. Without the
initialization, it may contain an undefined value which results in the
following segmentation fault:
# perf top --sort comm -g --ignore-callees=do_idle
terminates with:
#0 0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6
#1 0x00007ffff55e3802 in strdup () from /lib64/libc.so.6
#2 0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489
#3 hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564
#4 0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420,
sample_self=sample_self@entry=true) at util/hist.c:657
#5 0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0,
sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288
#6 0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38)
at util/hist.c:1056
#7 iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056
#8 0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0)
at util/hist.c:1231
#9 0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0)
at builtin-top.c:842
#10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202
#11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244
#12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323
#13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339
#14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341
#15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339
#16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114
#17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0
#18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6
If you look at the frame #2, the code is:
488 if (he->srcline) {
489 he->srcline = strdup(he->srcline);
490 if (he->srcline == NULL)
491 goto err_rawdata;
492 }
If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish),
it gets strdupped and strdupping a rubbish random string causes the problem.
Also, if you look at the commit d0f4c6d67a41, it adds the srcline property
into the struct, but not initializing it everywhere needed.
Committer notes:
Now I see, when using --ignore-callees=do_idle we end up here at line
2189 in add_callchain_ip():
2181 if (al.sym != NULL) {
2182 if (perf_hpp_list.parent && !*parent &&
2183 symbol__match_regex(al.sym, &parent_regex))
2184 *parent = al.sym;
2185 else if (have_ignore_callees && root_al &&
2186 symbol__match_regex(al.sym, &ignore_callees_regex)) {
2187 /* Treat this symbol as the root,
2188 forgetting its callees. */
2189 *root_al = al;
2190 callchain_cursor_reset(cursor);
2191 }
2192 }
And the al that doesn't have the ->srcline field initialized will be
copied to the root_al, so then, back to:
Adrian Hunter [Sat, 11 Sep 2021 13:30:53 +0000 (16:30 +0300)]
perf script: Fix ip display when type != attr->type
set_print_ip_opts() was not being called when type != attr->type
because there is not a one-to-one relationship between output types
and attr->type. That resulted in ip not printing.
The attr_type() function is removed, and the match of attr->type to
output type is corrected.
Example on ADL using taskset to select an atom cpu:
# perf record -e cpu_atom/cpu-cycles/ taskset 0x1000 uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.003 MB perf.data (7 samples) ]
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lore.kernel.org/lkml/20210911133053.15682-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ravi Bangoria [Sat, 11 Sep 2021 04:38:53 +0000 (10:08 +0530)]
perf annotate: Fix fused instr logic for assembly functions
Some x86 microarchitectures fuse a subset of cmp/test/ALU instructions
with branch instructions, and thus perf annotate highlight such valid
pairs as fused.
When annotated with source, perf uses struct disasm_line to contain
either source or instruction line from objdump output. Usually, a C
statement generates multiple instructions which include such
cmp/test/ALU + branch instruction pairs. But in case of assembly
function, each individual assembly source line generate one
instruction.
The 'perf annotate' instruction fusion logic assumes the previous
disasm_line as the previous instruction line, which is wrong because,
for assembly function, previous disasm_line contains source line. And
thus perf fails to highlight valid fused instruction pairs for assembly
functions.
Fix it by searching backward until we find an instruction line and
consider that disasm_line as fused with current branch instruction.
Before:
│ cmpq %rcx, RIP+8(%rsp)
0.00 │ cmp %rcx,0x88(%rsp)
│ je .Lerror_bad_iret <--- Source line
0.14 │ ┌──je b4 <--- Instruction line
│ │movl %ecx, %eax
Reviewed-by: Jin Yao <yao.jin@linux.intel.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kim Phillips <kim.phillips@amd.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org>
Link: https //lore.kernel.org/r/20210911043854.8373-1-ravi.bangoria@amd.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
projects / kernel.git / log