New conflicts in sched/core due to the following upstream fixes:
44585f7bc0 ("psi: fix "defined but not used" warnings when CONFIG_PROC_FS=n")
a06247c680 ("psi: Fix uaf issue when psi trigger is destroyed while being polled")
Conflicts:
include/linux/psi_types.h
kernel/sched/psi.c
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With unprivileged eBPF enabled, eIBRS (without retpoline) is vulnerable
to Spectre v2 BHB-based attacks.
When both are enabled, print a warning message and report it in the
'spectre_v2' sysfs vulnerabilities file.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Thanks to the chaps at VUsec it is now clear that eIBRS is not
sufficient, therefore allow enabling of retpolines along with eIBRS.
Add spectre_v2=eibrs, spectre_v2=eibrs,lfence and
spectre_v2=eibrs,retpoline options to explicitly pick your preferred
means of mitigation.
Since there's new mitigations there's also user visible changes in
/sys/devices/system/cpu/vulnerabilities/spectre_v2 to reflect these
new mitigations.
[ bp: Massage commit message, trim error messages,
do more precise eIBRS mode checking. ]
Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Patrick Colp <patrick.colp@oracle.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
The RETPOLINE_AMD name is unfortunate since it isn't necessarily
AMD only, in fact Hygon also uses it. Furthermore it will likely be
sufficient for some Intel processors. Therefore rename the thing to
RETPOLINE_LFENCE to better describe what it is.
Add the spectre_v2=retpoline,lfence option as an alias to
spectre_v2=retpoline,amd to preserve existing setups. However, the output
of /sys/devices/system/cpu/vulnerabilities/spectre_v2 will be changed.
[ bp: Fix typos, massage. ]
Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Pull x86 fixes from Borislav Petkov:
- Fix the ptrace regset xfpregs_set() callback to behave according to
the ABI
- Handle poisoned pages properly in the SGX reclaimer code
* tag 'x86_urgent_for_v5.17_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ptrace: Fix xfpregs_set()'s incorrect xmm clearing
x86/sgx: Fix missing poison handling in reclaimer
A rare kernel panic scenario can happen when the following conditions
are met due to an erratum on fast string copy instructions:
1) An uncorrected error.
2) That error must be in first cache line of a page.
3) Kernel must execute page_copy from the page immediately before that
page.
The fast string copy instructions ("REP; MOVS*") could consume an
uncorrectable memory error in the cache line _right after_ the desired
region to copy and raise an MCE.
Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string
copy and will avoid such spurious machine checks. However, that is less
preferable due to the permanent performance impact. Considering memory
poison is rare, it's desirable to keep fast string copy enabled until an
MCE is seen.
Intel has confirmed the following:
1. The CPU erratum of fast string copy only applies to Skylake,
Cascade Lake and Cooper Lake generations.
Directly return from the MCE handler:
2. Will result in complete execution of the "REP; MOVS*" with no data
loss or corruption.
3. Will not result in another MCE firing on the next poisoned cache line
due to "REP; MOVS*".
4. Will resume execution from a correct point in code.
5. Will result in the same instruction that triggered the MCE firing a
second MCE immediately for any other software recoverable data fetch
errors.
6. Is not safe without disabling the fast string copy, as the next fast
string copy of the same buffer on the same CPU would result in a PANIC
MCE.
This should mitigate the erratum completely with the only caveat that
the fast string copy is disabled on the affected hyper thread thus
performance degradation.
This is still better than the OS crashing on MCEs raised on an
irrelevant process due to "REP; MOVS*' accesses in a kernel context,
e.g., copy_page.
Tested:
Injected errors on 1st cache line of 8 anonymous pages of process
'proc1' and observed MCE consumption from 'proc2' with no panic
(directly returned).
Without the fix, the host panicked within a few minutes on a
random 'proc2' process due to kernel access from copy_page.
[ bp: Fix comment style + touch ups, zap an unlikely(), improve the
quirk function's readability. ]
Signed-off-by: Jue Wang <juew@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20220218013209.2436006-1-juew@google.com
Where an architecture selects HAVE_STATIC_CALL but not
HAVE_STATIC_CALL_INLINE, each static call has an out-of-line trampoline
which will either branch to a callee or return to the caller.
On such architectures, a number of constraints can conspire to make
those trampolines more complicated and potentially less useful than we'd
like. For example:
* Hardware and software control flow integrity schemes can require the
addition of "landing pad" instructions (e.g. `BTI` for arm64), which
will also be present at the "real" callee.
* Limited branch ranges can require that trampolines generate or load an
address into a register and perform an indirect branch (or at least
have a slow path that does so). This loses some of the benefits of
having a direct branch.
* Interaction with SW CFI schemes can be complicated and fragile, e.g.
requiring that we can recognise idiomatic codegen and remove
indirections understand, at least until clang proves more helpful
mechanisms for dealing with this.
For PREEMPT_DYNAMIC, we don't need the full power of static calls, as we
really only need to enable/disable specific preemption functions. We can
achieve the same effect without a number of the pain points above by
using static keys to fold early returns into the preemption functions
themselves rather than in an out-of-line trampoline, effectively
inlining the trampoline into the start of the function.
For arm64, this results in good code generation. For example, the
dynamic_cond_resched() wrapper looks as follows when enabled. When
disabled, the first `B` is replaced with a `NOP`, resulting in an early
return.
| <dynamic_cond_resched>:
| bti c
| b <dynamic_cond_resched+0x10> // or `nop`
| mov w0, #0x0
| ret
| mrs x0, sp_el0
| ldr x0, [x0, #8]
| cbnz x0, <dynamic_cond_resched+0x8>
| paciasp
| stp x29, x30, [sp, #-16]!
| mov x29, sp
| bl <preempt_schedule_common>
| mov w0, #0x1
| ldp x29, x30, [sp], #16
| autiasp
| ret
... compared to the regular form of the function:
| <__cond_resched>:
| bti c
| mrs x0, sp_el0
| ldr x1, [x0, #8]
| cbz x1, <__cond_resched+0x18>
| mov w0, #0x0
| ret
| paciasp
| stp x29, x30, [sp, #-16]!
| mov x29, sp
| bl <preempt_schedule_common>
| mov w0, #0x1
| ldp x29, x30, [sp], #16
| autiasp
| ret
Any architecture which implements static keys should be able to use this
to implement PREEMPT_DYNAMIC with similar cost to non-inlined static
calls. Since this is likely to have greater overhead than (inlined)
static calls, PREEMPT_DYNAMIC is only defaulted to enabled when
HAVE_PREEMPT_DYNAMIC_CALL is selected.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20220214165216.2231574-6-mark.rutland@arm.com
Currently sched_dynamic_update needs to open-code the enabled/disabled
function names for each preemption model it supports, when in practice
this is a boolean enabled/disabled state for each function.
Make this clearer and avoid repetition by defining the enabled/disabled
states at the function definition, and using helper macros to perform the
static_call_update(). Where x86 currently overrides the enabled
function, it is made to provide both the enabled and disabled states for
consistency, with defaults provided by the core code otherwise.
In subsequent patches this will allow us to support PREEMPT_DYNAMIC
without static calls.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20220214165216.2231574-3-mark.rutland@arm.com
Remove mmu_audit.c and all its collateral, the auditing code has suffered
severe bitrot, ironically partly due to shadow paging being more stable
and thus not benefiting as much from auditing, but mostly due to TDP
supplanting shadow paging for non-nested guests and shadowing of nested
TDP not heavily stressing the logic that is being audited.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A few vendor callbacks are only used by VMX, but they return an integer
or bool value. Introduce KVM_X86_OP_OPTIONAL_RET0 for them: if a func is
NULL in struct kvm_x86_ops, it will be changed to __static_call_return0
when updating static calls.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
All their invocations are conditional on vcpu->arch.apicv_active,
meaning that they need not be implemented by vendor code: even
though at the moment both vendors implement APIC virtualization,
all of them can be optional. In fact SVM does not need many of
them, and their implementation can be deleted now.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use the newly corrected KVM_X86_OP annotations to warn about possible
NULL pointer dereferences as soon as the vendor module is loaded.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The original use of KVM_X86_OP_NULL, which was to mark calls
that do not follow a specific naming convention, is not in use
anymore. Instead, let's mark calls that are optional because
they are always invoked within conditionals or with static_call_cond.
Those that are _not_, i.e. those that are defined with KVM_X86_OP,
must be defined by both vendor modules or some kind of NULL pointer
dereference is bound to happen at runtime.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SVM implements neither update_emulated_instruction nor
set_apic_access_page_addr. Remove an "if" by calling them
with static_call_cond().
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The two ioctls used to implement userspace-accelerated TPR,
KVM_TPR_ACCESS_REPORTING and KVM_SET_VAPIC_ADDR, are available
even if hardware-accelerated TPR can be used. So there is
no reason not to report KVM_CAP_VAPIC.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
xfpregs_set() handles 32-bit REGSET_XFP and 64-bit REGSET_FP. The actual
code treats these regsets as modern FX state (i.e. the beginning part of
XSTATE). The declarations of the regsets thought they were the legacy
i387 format. The code thought they were the 32-bit (no xmm8..15) variant
of XSTATE and, for good measure, made the high bits disappear by zeroing
the wrong part of the buffer. The latter broke ptrace, and everything
else confused anyone trying to understand the code. In particular, the
nonsense definitions of the regsets confused me when I wrote this code.
Clean this all up. Change the declarations to match reality (which
shouldn't change the generated code, let alone the ABI) and fix
xfpregs_set() to clear the correct bits and to only do so for 32-bit
callers.
Fixes: 6164331d15 ("x86/fpu: Rewrite xfpregs_set()")
Reported-by: Luís Ferreira <contact@lsferreira.net>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215524
Link: https://lore.kernel.org/r/YgpFnZpF01WwR8wU@zn.tnic
For SEV-ES VMs with mirrors to be intra-host migrated they need to be
able to migrate with the mirror. This is due to that fact that all VMSAs
need to be added into the VM with LAUNCH_UPDATE_VMSA before
lAUNCH_FINISH. Allowing migration with mirrors allows users of SEV-ES to
keep the mirror VMs VMSAs during migration.
Adds a list of mirror VMs for the original VM iterate through during its
migration. During the iteration the owner pointers can be updated from
the source to the destination. This fixes the ASID leaking issue which
caused the blocking of migration of VMs with mirrors.
Signed-off-by: Peter Gonda <pgonda@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Marc Orr <marcorr@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Message-Id: <20220211193634.3183388-1-pgonda@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On non-x86_64 builds, helpers gtod_is_based_on_tsc() and
kvm_guest_supported_xfd() are defined but never used. Because these are
static inline but are in a .c file, some compilers do warn for them with
-Wunused-function, which becomes an error if -Werror is present.
Add #ifdef so they are only defined in x86_64 builds.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Message-Id: <20220218034100.115702-1-leobras@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The SGX reclaimer code lacks page poison handling in its main
free path. This can lead to avoidable machine checks if a
poisoned page is freed and reallocated instead of being
isolated.
A troublesome scenario is:
1. Machine check (#MC) occurs (asynchronous, !MF_ACTION_REQUIRED)
2. arch_memory_failure() is eventually called
3. (SGX) page->poison set to 1
4. Page is reclaimed
5. Page added to normal free lists by sgx_reclaim_pages()
^ This is the bug (poison pages should be isolated on the
sgx_poison_page_list instead)
6. Page is reallocated by some innocent enclave, a second (synchronous)
in-kernel #MC is induced, probably during EADD instruction.
^ This is the fallout from the bug
(6) is unfortunate and can be avoided by replacing the open coded
enclave page freeing code in the reclaimer with sgx_free_epc_page()
to obtain support for poison page handling that includes placing the
poisoned page on the correct list.
Fixes: d6d261bded ("x86/sgx: Add new sgx_epc_page flag bit to mark free pages")
Fixes: 992801ae92 ("x86/sgx: Initial poison handling for dirty and free pages")
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/dcc95eb2aaefb042527ac50d0a50738c7c160dac.1643830353.git.reinette.chatre@intel.com
kvm_vcpu_arch currently contains the guest supported features in both
guest_supported_xcr0 and guest_fpu.fpstate->user_xfeatures field.
Currently both fields are set to the same value in
kvm_vcpu_after_set_cpuid() and are not changed anywhere else after that.
Since it's not good to keep duplicated data, remove guest_supported_xcr0.
To keep the code more readable, introduce kvm_guest_supported_xcr()
and kvm_guest_supported_xfd() to replace the previous usages of
guest_supported_xcr0.
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Message-Id: <20220217053028.96432-3-leobras@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
During host/guest switch (like in kvm_arch_vcpu_ioctl_run()), the kernel
swaps the fpu between host/guest contexts, by using fpu_swap_kvm_fpstate().
When xsave feature is available, the fpu swap is done by:
- xsave(s) instruction, with guest's fpstate->xfeatures as mask, is used
to store the current state of the fpu registers to a buffer.
- xrstor(s) instruction, with (fpu_kernel_cfg.max_features &
XFEATURE_MASK_FPSTATE) as mask, is used to put the buffer into fpu regs.
For xsave(s) the mask is used to limit what parts of the fpu regs will
be copied to the buffer. Likewise on xrstor(s), the mask is used to
limit what parts of the fpu regs will be changed.
The mask for xsave(s), the guest's fpstate->xfeatures, is defined on
kvm_arch_vcpu_create(), which (in summary) sets it to all features
supported by the cpu which are enabled on kernel config.
This means that xsave(s) will save to guest buffer all the fpu regs
contents the cpu has enabled when the guest is paused, even if they
are not used.
This would not be an issue, if xrstor(s) would also do that.
xrstor(s)'s mask for host/guest swap is basically every valid feature
contained in kernel config, except XFEATURE_MASK_PKRU.
Accordingto kernel src, it is instead switched in switch_to() and
flush_thread().
Then, the following happens with a host supporting PKRU starts a
guest that does not support it:
1 - Host has XFEATURE_MASK_PKRU set. 1st switch to guest,
2 - xsave(s) fpu regs to host fpustate (buffer has XFEATURE_MASK_PKRU)
3 - xrstor(s) guest fpustate to fpu regs (fpu regs have XFEATURE_MASK_PKRU)
4 - guest runs, then switch back to host,
5 - xsave(s) fpu regs to guest fpstate (buffer now have XFEATURE_MASK_PKRU)
6 - xrstor(s) host fpstate to fpu regs.
7 - kvm_vcpu_ioctl_x86_get_xsave() copy guest fpstate to userspace (with
XFEATURE_MASK_PKRU, which should not be supported by guest vcpu)
On 5, even though the guest does not support PKRU, it does have the flag
set on guest fpstate, which is transferred to userspace via vcpu ioctl
KVM_GET_XSAVE.
This becomes a problem when the user decides on migrating the above guest
to another machine that does not support PKRU: the new host restores
guest's fpu regs to as they were before (xrstor(s)), but since the new
host don't support PKRU, a general-protection exception ocurs in xrstor(s)
and that crashes the guest.
This can be solved by making the guest's fpstate->user_xfeatures hold
a copy of guest_supported_xcr0. This way, on 7 the only flags copied to
userspace will be the ones compatible to guest requirements, and thus
there will be no issue during migration.
As a bonus, it will also fail if userspace tries to set fpu features
(with the KVM_SET_XSAVE ioctl) that are not compatible to the guest
configuration. Such features will never be returned by KVM_GET_XSAVE
or KVM_GET_XSAVE2.
Also, since kvm_vcpu_after_set_cpuid() now sets fpstate->user_xfeatures,
there is not need to set it in kvm_check_cpuid(). So, change
fpstate_realloc() so it does not touch fpstate->user_xfeatures if a
non-NULL guest_fpu is passed, which is the case when kvm_check_cpuid()
calls it.
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Message-Id: <20220217053028.96432-2-leobras@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If vcpu has tsc_always_catchup set each request updates pvclock data.
KVM_HC_CLOCK_PAIRING consumers such as ptp_kvm_x86 rely on tsc read on
host's side and do hypercall inside pvclock_read_retry loop leading to
infinite loop in such situation.
v3:
Removed warn
Changed return code to KVM_EFAULT
v2:
Added warn
Signed-off-by: Anton Romanov <romanton@google.com>
Message-Id: <20220216182653.506850-1-romanton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Follow the precedent set by other architectures that support the VCPU
ioctl, KVM_ENABLE_CAP, and advertise the VM extension, KVM_CAP_ENABLE_CAP.
This way, userspace can ensure that KVM_ENABLE_CAP is available on a
vcpu before using it.
Fixes: 5c919412fe ("kvm/x86: Hyper-V synthetic interrupt controller")
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Message-Id: <20220214212950.1776943-1-aaronlewis@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].
This code was transformed with the help of Coccinelle:
(next-20220214$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)
@@
identifier S, member, array;
type T1, T2;
@@
struct S {
...
T1 member;
T2 array[
- 0
];
};
UAPI and wireless changes were intentionally excluded from this patch
and will be sent out separately.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://github.com/KSPP/linux/issues/78
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
asm/shmbuf.h is currently excluded from the UAPI compile-test because of
the errors like follows:
HDRTEST usr/include/asm/shmbuf.h
In file included from ./usr/include/asm/shmbuf.h:6,
from <command-line>:
./usr/include/asm-generic/shmbuf.h:26:33: error: field ‘shm_perm’ has incomplete type
26 | struct ipc64_perm shm_perm; /* operation perms */
| ^~~~~~~~
./usr/include/asm-generic/shmbuf.h:27:9: error: unknown type name ‘size_t’
27 | size_t shm_segsz; /* size of segment (bytes) */
| ^~~~~~
./usr/include/asm-generic/shmbuf.h:40:9: error: unknown type name ‘__kernel_pid_t’
40 | __kernel_pid_t shm_cpid; /* pid of creator */
| ^~~~~~~~~~~~~~
./usr/include/asm-generic/shmbuf.h:41:9: error: unknown type name ‘__kernel_pid_t’
41 | __kernel_pid_t shm_lpid; /* pid of last operator */
| ^~~~~~~~~~~~~~
The errors can be fixed by replacing size_t with __kernel_size_t and by
including proper headers.
Then, remove the no-header-test entry from user/include/Makefile.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
linux/signal.h and asm/signal.h are currently excluded from the UAPI
compile-test because of the errors like follows:
HDRTEST usr/include/asm/signal.h
In file included from <command-line>:
./usr/include/asm/signal.h:103:9: error: unknown type name ‘size_t’
103 | size_t ss_size;
| ^~~~~~
The errors can be fixed by replacing size_t with __kernel_size_t.
Then, remove the no-header-test entries from user/include/Makefile.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Currently, the SME CPU feature flag is reflective of whether the CPU
supports the feature but not whether it has been activated by the
kernel.
Change this around to clear the SME feature flag if the kernel is not
using it so userspace can determine if it is available and in use
from /proc/cpuinfo.
As the feature flag is cleared on systems where SME isn't active, use
CPUID 0x8000001f to confirm SME availability before calling
native_wbinvd().
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20220216034446.2430634-1-mario.limonciello@amd.com
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Read HW interrupt pending state from the HW
x86:
- Don't truncate the performance event mask on AMD
- Fix Xen runstate updates to be atomic when preempting vCPU
- Fix for AMD AVIC interrupt injection race
- Several other AMD fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86/pmu: Use AMD64_RAW_EVENT_MASK for PERF_TYPE_RAW
KVM: x86/pmu: Don't truncate the PerfEvtSeln MSR when creating a perf event
KVM: SVM: fix race between interrupt delivery and AVIC inhibition
KVM: SVM: set IRR in svm_deliver_interrupt
KVM: SVM: extract avic_ring_doorbell
selftests: kvm: Remove absent target file
KVM: arm64: vgic: Read HW interrupt pending state from the HW
KVM: x86/xen: Fix runstate updates to be atomic when preempting vCPU
KVM: x86: SVM: move avic definitions from AMD's spec to svm.h
KVM: x86: lapic: don't touch irr_pending in kvm_apic_update_apicv when inhibiting it
KVM: x86: nSVM: deal with L1 hypervisor that intercepts interrupts but lets L2 control them
KVM: x86: nSVM: expose clean bit support to the guest
KVM: x86: nSVM/nVMX: set nested_run_pending on VM entry which is a result of RSM
KVM: x86: nSVM: mark vmcb01 as dirty when restoring SMM saved state
KVM: x86: nSVM: fix potential NULL derefernce on nested migration
KVM: x86: SVM: don't passthrough SMAP/SMEP/PKE bits in !NPT && !gCR0.PG case
Revert "svm: Add warning message for AVIC IPI invalid target"
All tasks start with PASID state disabled. This means that the first
time they execute an ENQCMD instruction they will take a #GP fault.
Modify the #GP fault handler to check if the "mm" for the task has
already been allocated a PASID. If so, try to fix the #GP fault by
loading the IA32_PASID MSR.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220207230254.3342514-9-fenghua.yu@intel.com
The kernel must allocate a Process Address Space ID (PASID) on behalf of
each process which will use ENQCMD and program it into the new MSR to
communicate the process identity to platform hardware. ENQCMD uses the
PASID stored in this MSR to tag requests from this process.
The PASID state must be cleared on fork() since fork creates a
new address space.
For clone(), it would be functionally OK to copy the PASID. However,
clearing it is _also_ functionally OK since any PASID use will trigger
the #GP handler to populate the MSR.
Copying the PASID state has two main downsides:
* It requires differentiating fork() and clone() in the code,
both in the FPU code and keeping tsk->pasid_activated consistent.
* It guarantees that the PASID is out of its init state, which
incurs small but non-zero cost on every XSAVE/XRSTOR.
The main downside of clearing the PASID at fpstate copy is the future,
one-time #GP for the thread.
Use the simplest approach: clear the PASID state both on clone() and
fork(). Rely on the #GP handler for MSR population in children.
Also, just clear the PASID bit from xfeatures if XSAVE is supported.
This will have no effect on systems that do not have PASID support. It
is virtually zero overhead because 'dst_fpu' was just written and
the whole thing is cache hot.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220207230254.3342514-7-fenghua.yu@intel.com
Use "avic" instead of "svm" for SVM's all of APICv hooks and make a few
additional funciton name tweaks so that the AVIC functions conform to
their associated kvm_x86_ops hooks.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-19-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AMD's event select is 3 nybbles, with the high nybble in bits 35:32 of
a PerfEvtSeln MSR. Don't drop the high nybble when setting up the
config field of a perf_event_attr structure for a call to
perf_event_create_kernel_counter().
Fixes: ca724305a2 ("KVM: x86/vPMU: Implement AMD vPMU code for KVM")
Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Message-Id: <20220203014813.2130559-1-jmattson@google.com>
Reviewed-by: David Dunn <daviddunn@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As done for memcpy(), also update memmove() to use the same tightened
compile-time checks under CONFIG_FORTIFY_SOURCE.
Signed-off-by: Kees Cook <keescook@chromium.org>
Explicitly zero select fields in the emulator's decode cache instead of
zeroing the fields via a gross memset() that spans six fields. gcc and
clang are both clever enough to batch the first five fields into a single
quadword MOV, i.e. memset() and individually zeroing generate identical
code.
Removing the wart also prepares KVM for FORTIFY_SOURCE performing
compile-time and run-time field bounds checking for memset().
No functional change intended.
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/lkml/YR0jIEzEcUom/7rd@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
The arch helpers do not have explicit KASAN instrumentation. Use them in
noinstr code.
Inline a couple more functions with single call sites, while at it:
mce_severity_amd_smca() has a single call-site which is noinstr so force
the inlining and fix:
vmlinux.o: warning: objtool: mce_severity_amd.constprop.0()+0xca: call to \
mce_severity_amd_smca() leaves .noinstr.text section
Always inline mca_msr_reg():
text data bss dec hex filename
16065240 128031326 36405368 180501934 ac23dae vmlinux.before
16065240 128031294 36405368 180501902 ac23d8e vmlinux.after
and mce_no_way_out() as the latter one is used only once, to fix:
vmlinux.o: warning: objtool: mce_read_aux()+0x53: call to mca_msr_reg() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_machine_check()+0xc9: call to mce_no_way_out() leaves .noinstr.text section
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20220204083015.17317-4-bp@alien8.de
Pull objtool fix from Borislav Petkov:
"Fix a case where objtool would mistakenly warn about instructions
being unreachable"
* tag 'objtool_urgent_for_v5.17_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/bug: Merge annotate_reachable() into _BUG_FLAGS() asm
Pull x86 fix from Borislav Petkov:
"Prevent softlockups when tearing down large SGX enclaves"
* tag 'x86_urgent_for_v5.17_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/sgx: Silence softlockup detection when releasing large enclaves
Instrumentation glue like KASAN causes the following warning:
vmlinux.o: warning: objtool: mce_gather_info()+0x5f: call to v8086_mode.constprop.0() leaves .noinstr.text section
due to gcc creating a function call for that oneliner. Force-inline it
and even save some vmlinux bytes (.config is close to an allmodconfig):
text data bss dec hex filename
209431677 208257651 34411048 452100376 1af28118 vmlinux.before
209431519 208257615 34411048 452100182 1af28056 vmlinux.after
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20220204083015.17317-3-bp@alien8.de
Add a x86-specific cpumask_clear_cpu() helper which will be used in
places where the explicit KASAN-instrumentation in the *_bit() helpers
is unwanted.
Also, always inline two more cpumask generic helpers.
allyesconfig:
text data bss dec hex filename
190553143 159425889 32076404 382055436 16c5b40c vmlinux.before
190551812 159424945 32076404 382053161 16c5ab29 vmlinux.after
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20220204083015.17317-2-bp@alien8.de
