Recent gcc compilers (gcc 9.1) generate warnings about an out of bounds
memset, if the memset goes accross several fields of a struct. This
generated a couple of warnings on x86_64 builds in sanitize_boot_params().
Fix this by explicitly saving the fields in struct boot_params
that are intended to be preserved, and zeroing all the rest.
[ tglx: Tagged for stable as it breaks the warning free build there as well ]
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190731054627.5627-2-jhubbard@nvidia.com
Pull kvm fixes from Paolo Bonzini:
"Bugfixes (arm and x86) and cleanups"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
selftests: kvm: Adding config fragments
KVM: selftests: Update gitignore file for latest changes
kvm: remove unnecessary PageReserved check
KVM: arm/arm64: vgic: Reevaluate level sensitive interrupts on enable
KVM: arm: Don't write junk to CP15 registers on reset
KVM: arm64: Don't write junk to sysregs on reset
KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block
x86: kvm: remove useless calls to kvm_para_available
KVM: no need to check return value of debugfs_create functions
KVM: remove kvm_arch_has_vcpu_debugfs()
KVM: Fix leak vCPU's VMCS value into other pCPU
KVM: Check preempted_in_kernel for involuntary preemption
KVM: LAPIC: Don't need to wakeup vCPU twice afer timer fire
arm64: KVM: hyp: debug-sr: Mark expected switch fall-through
KVM: arm64: Update kvm_arm_exception_class and esr_class_str for new EC
KVM: arm: vgic-v3: Mark expected switch fall-through
arm64: KVM: regmap: Fix unexpected switch fall-through
KVM: arm/arm64: Introduce kvm_pmu_vcpu_init() to setup PMU counter index
KVM/arm fixes for 5.3
- A bunch of switch/case fall-through annotation, fixing one actual bug
- Fix PMU reset bug
- Add missing exception class debug strings
Now that generic code doesn't reference them, move sme_active() and
sme_me_mask to x86's <asm/mem_encrypt.h>.
Also remove the export for sme_active() since it's only used in files that
won't be built as modules. sme_me_mask on the other hand is used in
arch/x86/kvm/svm.c (via __sme_set() and __psp_pa()) which can be built as a
module so its export needs to stay.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190806044919.10622-5-bauerman@linux.ibm.com
The SGI UV UEFI machines are tightly coupled to the x86 architecture
so there is no need to keep any awareness of its existence in the
generic EFI layer, especially since we already have the infrastructure
to handle arch-specific configuration tables, and were even already
using it to some extent.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
The function efi_is_table_address() and the associated array of table
pointers is specific to x86. Since we will be adding some more x86
specific tables, let's move this code out of the generic code first.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
The function override_function_with_return() is defined separately for
each architecture and every architecture's definition is almost same
with each other. E.g. x86 and powerpc both define function in its own
asm/error-injection.h header and override_function_with_return() has
the same definition, the only difference is that x86 defines an extra
function just_return_func() but it is specific for x86 and is only used
by x86's override_function_with_return(), so don't need to export this
function.
This patch consolidates override_function_with_return() definition into
asm-generic/error-injection.h header, thus all architectures can use the
common definition. As result, the architecture specific headers are
removed; the include/linux/error-injection.h header also changes to
include asm-generic/error-injection.h header rather than architecture
header, furthermore, it includes linux/compiler.h for successful
compilation.
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Pull pti updates from Thomas Gleixner:
"The performance deterioration departement is not proud at all to
present yet another set of speculation fences to mitigate the next
chapter in the 'what could possibly go wrong' story.
The new vulnerability belongs to the Spectre class and affects GS
based data accesses and has therefore been dubbed 'Grand Schemozzle'
for secret communication purposes. It's officially listed as
CVE-2019-1125.
Conditional branches in the entry paths which contain a SWAPGS
instruction (interrupts and exceptions) can be mis-speculated which
results in speculative accesses with a wrong GS base.
This can happen on entry from user mode through a mis-speculated
branch which takes the entry from kernel mode path and therefore does
not execute the SWAPGS instruction. The following speculative accesses
are done with user GS base.
On entry from kernel mode the mis-speculated branch executes the
SWAPGS instruction in the entry from user mode path which has the same
effect that the following GS based accesses are done with user GS
base.
If there is a disclosure gadget available in these code paths the
mis-speculated data access can be leaked through the usual side
channels.
The entry from user mode issue affects all CPUs which have speculative
execution. The entry from kernel mode issue affects only Intel CPUs
which can speculate through SWAPGS. On CPUs from other vendors SWAPGS
has semantics which prevent that.
SMAP migitates both problems but only when the CPU is not affected by
the Meltdown vulnerability.
The mitigation is to issue LFENCE instructions in the entry from
kernel mode path for all affected CPUs and on the affected Intel CPUs
also in the entry from user mode path unless PTI is enabled because
the CR3 write is serializing.
The fences are as usual enabled conditionally and can be completely
disabled on the kernel command line. The Spectre V1 documentation is
updated accordingly.
A big "Thank You!" goes to Josh for doing the heavy lifting for this
round of hardware misfeature 'repair'. Of course also "Thank You!" to
everybody else who contributed in one way or the other"
* 'x86/grand-schemozzle' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Documentation: Add swapgs description to the Spectre v1 documentation
x86/speculation/swapgs: Exclude ATOMs from speculation through SWAPGS
x86/entry/64: Use JMP instead of JMPQ
x86/speculation: Enable Spectre v1 swapgs mitigations
x86/speculation: Prepare entry code for Spectre v1 swapgs mitigations
There is no need for this function as all arches have to implement
kvm_arch_create_vcpu_debugfs() no matter what. A #define symbol
let us actually simplify the code.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
After commit d73eb57b80 (KVM: Boost vCPUs that are delivering interrupts), a
five years old bug is exposed. Running ebizzy benchmark in three 80 vCPUs VMs
on one 80 pCPUs Skylake server, a lot of rcu_sched stall warning splatting
in the VMs after stress testing:
INFO: rcu_sched detected stalls on CPUs/tasks: { 4 41 57 62 77} (detected by 15, t=60004 jiffies, g=899, c=898, q=15073)
Call Trace:
flush_tlb_mm_range+0x68/0x140
tlb_flush_mmu.part.75+0x37/0xe0
tlb_finish_mmu+0x55/0x60
zap_page_range+0x142/0x190
SyS_madvise+0x3cd/0x9c0
system_call_fastpath+0x1c/0x21
swait_active() sustains to be true before finish_swait() is called in
kvm_vcpu_block(), voluntarily preempted vCPUs are taken into account
by kvm_vcpu_on_spin() loop greatly increases the probability condition
kvm_arch_vcpu_runnable(vcpu) is checked and can be true, when APICv
is enabled the yield-candidate vCPU's VMCS RVI field leaks(by
vmx_sync_pir_to_irr()) into spinning-on-a-taken-lock vCPU's current
VMCS.
This patch fixes it by checking conservatively a subset of events.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Cc: stable@vger.kernel.org
Fixes: 98f4a1467 (KVM: add kvm_arch_vcpu_runnable() test to kvm_vcpu_on_spin() loop)
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The generic VDSO implementation uses the Y2038 safe clock_gettime64() and
clock_getres_time64() syscalls as fallback for 32bit VDSO. This breaks
seccomp setups because these syscalls might be not (yet) allowed.
Implement the 32bit variants which use the legacy syscalls and select the
variant in the core library.
The 64bit time variants are not removed because they are required for the
time64 based vdso accessors.
Fixes: 7ac8707479 ("x86/vdso: Switch to generic vDSO implementation")
Reported-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20190728131648.879156507@linutronix.de
When performing guest side polling, it is not necessary to
also perform host side polling.
So disable host side polling, via the new MSR interface,
when loading cpuidle-haltpoll driver.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Intel provided the following information:
On all current Atom processors, instructions that use a segment register
value (e.g. a load or store) will not speculatively execute before the
last writer of that segment retires. Thus they will not use a
speculatively written segment value.
That means on ATOMs there is no speculation through SWAPGS, so the SWAPGS
entry paths can be excluded from the extra LFENCE if PTI is disabled.
Create a separate bug flag for the through SWAPGS speculation and mark all
out-of-order ATOMs and AMD/HYGON CPUs as not affected. The in-order ATOMs
are excluded from the whole mitigation mess anyway.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
The AES-NI code contains fallbacks for invocations that occur from a
context where the SIMD unit is unavailable, which really only occurs
when running in softirq context that was entered from a hard IRQ that
was taken while running kernel code that was already using the FPU.
That means performance is not really a consideration, and we can just
use the new library code for this use case, which has a smaller
footprint and is believed to be time invariant. This will allow us to
drop the non-SIMD asm routines in a subsequent patch.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
All callers of apic->send_IPI_all() and apic->send_IPI_allbutself() contain
the decision logic for shorthand invocation already and invoke
send_IPI_mask() if the prereqisites are not satisfied.
Remove the now redundant decision logic in the APIC code and the duplicate
helper in probe_64.c.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105221.042964120@linutronix.de
The IPI shorthand functionality delivers IPI/NMI broadcasts to all CPUs in
the system. This can have similar side effects as the MCE broadcasting when
CPUs are waiting in the BIOS or are offlined.
The kernel tracks already the state of offlined CPUs whether they have been
brought up at least once so that the CR4 MCE bit is set to make sure that
MCE broadcasts can't brick the machine.
Utilize that information and compare it to the cpu_present_mask. If all
present CPUs have been brought up at least once then the broadcast side
effect is mitigated by disabling regular interrupt/IPI delivery in the APIC
itself and by the cpu offline check at the begin of the NMI handler.
Use a static key to switch between broadcasting via shorthands or sending
the IPI/NMI one by one.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105220.386410643@linutronix.de
In order to support IPI/NMI broadcasting via the shorthand mechanism side
effects of shorthands need to be mitigated:
Shorthand IPIs and NMIs hit all CPUs including unplugged CPUs
Neither of those can be handled on unplugged CPUs for obvious reasons.
It would be trivial to just fully disable the APIC via the enable bit in
MSR_APICBASE. But that's not possible because clearing that bit on systems
based on the 3 wire APIC bus would require a hardware reset to bring it
back as the APIC would lose track of bus arbitration. On systems with FSB
delivery APICBASE could be disabled, but it has to be guaranteed that no
interrupt is sent to the APIC while in that state and it's not clear from
the SDM whether it still responds to INIT/SIPI messages.
Therefore stay on the safe side and switch the APIC into soft disabled mode
so it won't deliver any regular vector to the CPU.
NMIs are still propagated to the 'dead' CPUs. To mitigate that add a check
for the CPU being offline on early nmi entry and if so bail.
Note, this cannot use the stop/restart_nmi() magic which is used in the
alternatives code. A dead CPU cannot invoke nmi_enter() or anything else
due to RCU and other reasons.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1907241723290.1791@nanos.tec.linutronix.de
arch_smt_update() will be used to control IPI/NMI broadcasting via the
shorthand mechanism. Keeping it in the bugs file and calling the apic
function from there is possible, but not really intuitive.
Move it to a neutral place and invoke the bugs function from there.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105219.910317273@linutronix.de
Pull KVM fixes from Paolo Bonzini:
"Bugfixes, a pvspinlock optimization, and documentation moving"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: X86: Boost queue head vCPU to mitigate lock waiter preemption
Documentation: move Documentation/virtual to Documentation/virt
KVM: nVMX: Set cached_vmcs12 and cached_shadow_vmcs12 NULL after free
KVM: X86: Dynamically allocate user_fpu
KVM: X86: Fix fpu state crash in kvm guest
Revert "kvm: x86: Use task structs fpu field for user"
KVM: nVMX: Clear pending KVM_REQ_GET_VMCS12_PAGES when leaving nested
load_mm_cr4() is always called with interrupts disabled from:
- switch_mm_irqs_off()
- refresh_pce(), which is a on_each_cpu() callback
Thus, disabling interrupts in cr4_set/clear_bits() is redundant.
Implement cr4_set/clear_bits_irqsoff() helpers, rename load_mm_cr4() to
load_mm_cr4_irqsoff() and use the new helpers. The new helpers do not need
a lockdep assert as __cr4_set() has one already.
The renaming in combination with the checks in __cr4_set() ensure that any
changes in the boundary conditions at the call sites will be detected.
[ tglx: Massaged change log ]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/0fbbcb64-5f26-4ffb-1bb9-4f5f48426893@siemens.com
After reverting commit 240c35a378 (kvm: x86: Use task structs fpu field
for user), struct kvm_vcpu is 19456 bytes on my server, PAGE_ALLOC_COSTLY_ORDER(3)
is the order at which allocations are deemed costly to service. In serveless
scenario, one host can service hundreds/thoudands firecracker/kata-container
instances, howerver, new instance will fail to launch after memory is too
fragmented to allocate kvm_vcpu struct on host, this was observed in some
cloud provider product environments.
This patch dynamically allocates user_fpu, kvm_vcpu is 15168 bytes now on my
Skylake server.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This reverts commit 240c35a378
("kvm: x86: Use task structs fpu field for user", 2018-11-06).
The commit is broken and causes QEMU's FPU state to be destroyed
when KVM_RUN is preempted.
Fixes: 240c35a378 ("kvm: x86: Use task structs fpu field for user")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AMD and Intel both have serializing lfence (X86_FEATURE_LFENCE_RDTSC).
They've both had it for a long time, and AMD has had it enabled in Linux
since Spectre v1 was announced.
Back then, there was a proposal to remove the serializing mfence feature
bit (X86_FEATURE_MFENCE_RDTSC), since both AMD and Intel have
serializing lfence. At the time, it was (ahem) speculated that some
hypervisors might not yet support its removal, so it remained for the
time being.
Now a year-and-a-half later, it should be safe to remove.
I asked Andrew Cooper about whether it's still needed:
So if you're virtualised, you've got no choice in the matter. lfence
is either dispatch-serialising or not on AMD, and you won't be able to
change it.
Furthermore, you can't accurately tell what state the bit is in, because
the MSR might not be virtualised at all, or may not reflect the true
state in hardware. Worse still, attempting to set the bit may not be
successful even if there isn't a fault for doing so.
Xen sets the DE_CFG bit unconditionally, as does Linux by the looks of
things (see MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT). ISTR other hypervisor
vendors saying the same, but I don't have any information to hand.
If you are running under a hypervisor which has been updated, then
lfence will almost certainly be dispatch-serialising in practice, and
you'll almost certainly see the bit already set in DE_CFG. If you're
running under a hypervisor which hasn't been patched since Spectre,
you've already lost in many more ways.
I'd argue that X86_FEATURE_MFENCE_RDTSC is not worth keeping.
So remove it. This will reduce some code rot, and also make it easier
to hook barrier_nospec() up to a cmdline disable for performance
raisins, without having to need an alternative_3() macro.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/d990aa51e40063acb9888e8c1b688e41355a9588.1562255067.git.jpoimboe@redhat.com
For unfortunate historical reasons, the x32 syscalls and the x86_64
syscalls are not all numbered the same. As an example, ioctl() is nr 16 on
x86_64 but 514 on x32.
This has potentially nasty consequences, since it means that there are two
valid RAX values to do ioctl(2) and two invalid RAX values. The valid
values are 16 (i.e. ioctl(2) using the x86_64 ABI) and (514 | 0x40000000)
(i.e. ioctl(2) using the x32 ABI).
The invalid values are 514 and (16 | 0x40000000). 514 will enter the
"COMPAT_SYSCALL_DEFINE3(ioctl, ...)" entry point with in_compat_syscall()
and in_x32_syscall() returning false, whereas (16 | 0x40000000) will enter
the native entry point with in_compat_syscall() and in_x32_syscall()
returning true. Both are bogus, and both will exercise code paths in the
kernel and in any running seccomp filters that really ought to be
unreachable.
Splitting out the x32 syscalls into their own tables, allows both bogus
invocations to return -ENOSYS. I've checked glibc, musl, and Bionic, and
all of them appear to call syscalls with their correct numbers, so this
change should have no effect on them.
There is an added benefit going forward: new syscalls that need special
handling on x32 can share the same number on x32 and x86_64. This means
that the special syscall range 512-547 can be treated as a legacy wart
instead of something that may need to be extended in the future.
Also add a selftest to verify the new behavior.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/208024256b764312598f014ebfb0a42472c19354.1562185330.git.luto@kernel.org
There is a lot of infrastructure for functionality which is used
exclusively in __{save,restore}_processor_state() on the suspend/resume
path.
cr8 is an alias of APIC_TASKPRI, and APIC_TASKPRI is saved/restored by
lapic_{suspend,resume}(). Saving and restoring cr8 independently of the
rest of the Local APIC state isn't a clever thing to be doing.
Delete the suspend/resume cr8 handling, which shrinks the size of struct
saved_context, and allows for the removal of both PVOPS.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20190715151641.29210-1-andrew.cooper3@citrix.com
Pull x86 fixes from Thomas Gleixner:
"A set of x86 specific fixes and updates:
- The CR2 corruption fixes which store CR2 early in the entry code
and hand the stored address to the fault handlers.
- Revert a forgotten leftover of the dropped FSGSBASE series.
- Plug a memory leak in the boot code.
- Make the Hyper-V assist functionality robust by zeroing the shadow
page.
- Remove a useless check for dead processes with LDT
- Update paravirt and VMware maintainers entries.
- A few cleanup patches addressing various compiler warnings"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry/64: Prevent clobbering of saved CR2 value
x86/hyper-v: Zero out the VP ASSIST PAGE on allocation
x86, boot: Remove multiple copy of static function sanitize_boot_params()
x86/boot/compressed/64: Remove unused variable
x86/boot/efi: Remove unused variables
x86/mm, tracing: Fix CR2 corruption
x86/entry/64: Update comments and sanity tests for create_gap
x86/entry/64: Simplify idtentry a little
x86/entry/32: Simplify common_exception
x86/paravirt: Make read_cr2() CALLEE_SAVE
MAINTAINERS: Update PARAVIRT_OPS_INTERFACE and VMWARE_HYPERVISOR_INTERFACE
x86/process: Delete useless check for dead process with LDT
x86: math-emu: Hide clang warnings for 16-bit overflow
x86/e820: Use proper booleans instead of 0/1
x86/apic: Silence -Wtype-limits compiler warnings
x86/mm: Free sme_early_buffer after init
x86/boot: Fix memory leak in default_get_smp_config()
Revert "x86/ptrace: Prevent ptrace from clearing the FS/GS selector" and fix the test
Pull core fixes from Thomas Gleixner:
- A collection of objtool fixes which address recent fallout partially
exposed by newer toolchains, clang, BPF and general code changes.
- Force USER_DS for user stack traces
[ Note: the "objtool fixes" are not all to objtool itself, but for
kernel code that triggers objtool warnings.
Things like missing function size annotations, or code that confuses
the unwinder etc. - Linus]
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
objtool: Support conditional retpolines
objtool: Convert insn type to enum
objtool: Fix seg fault on bad switch table entry
objtool: Support repeated uses of the same C jump table
objtool: Refactor jump table code
objtool: Refactor sibling call detection logic
objtool: Do frame pointer check before dead end check
objtool: Change dead_end_function() to return boolean
objtool: Warn on zero-length functions
objtool: Refactor function alias logic
objtool: Track original function across branches
objtool: Add mcsafe_handle_tail() to the uaccess safe list
bpf: Disable GCC -fgcse optimization for ___bpf_prog_run()
x86/uaccess: Remove redundant CLACs in getuser/putuser error paths
x86/uaccess: Don't leak AC flag into fentry from mcsafe_handle_tail()
x86/uaccess: Remove ELF function annotation from copy_user_handle_tail()
x86/head/64: Annotate start_cpu0() as non-callable
x86/entry: Fix thunk function ELF sizes
x86/kvm: Don't call kvm_spurious_fault() from .fixup
x86/kvm: Replace vmx_vmenter()'s call to kvm_spurious_fault() with UD2
...
Pull xen updates from Juergen Gross:
"Fixes and features:
- A series to introduce a common command line parameter for disabling
paravirtual extensions when running as a guest in virtualized
environment
- A fix for int3 handling in Xen pv guests
- Removal of the Xen-specific tmem driver as support of tmem in Xen
has been dropped (and it was experimental only)
- A security fix for running as Xen dom0 (XSA-300)
- A fix for IRQ handling when offlining cpus in Xen guests
- Some small cleanups"
* tag 'for-linus-5.3a-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: let alloc_xenballooned_pages() fail if not enough memory free
xen/pv: Fix a boot up hang revealed by int3 self test
x86/xen: Add "nopv" support for HVM guest
x86/paravirt: Remove const mark from x86_hyper_xen_hvm variable
xen: Map "xen_nopv" parameter to "nopv" and mark it obsolete
x86: Add "nopv" parameter to disable PV extensions
x86/xen: Mark xen_hvm_need_lapic() and xen_x2apic_para_available() as __init
xen: remove tmem driver
Revert "x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized"
xen/events: fix binding user event channels to cpus
After making a change to improve objtool's sibling call detection, it
started showing the following warning:
arch/x86/kvm/vmx/nested.o: warning: objtool: .fixup+0x15: sibling call from callable instruction with modified stack frame
The problem is the ____kvm_handle_fault_on_reboot() macro. It does a
fake call by pushing a fake RIP and doing a jump. That tricks the
unwinder into printing the function which triggered the exception,
rather than the .fixup code.
Instead of the hack to make it look like the original function made the
call, just change the macro so that the original function actually does
make the call. This allows removal of the hack, and also makes objtool
happy.
I triggered a vmx instruction exception and verified that the stack
trace is still sane:
kernel BUG at arch/x86/kvm/x86.c:358!
invalid opcode: 0000 [#1] SMP PTI
CPU: 28 PID: 4096 Comm: qemu-kvm Not tainted 5.2.0+ #16
Hardware name: Lenovo THINKSYSTEM SD530 -[7X2106Z000]-/-[7X2106Z000]-, BIOS -[TEE113Z-1.00]- 07/17/2017
RIP: 0010:kvm_spurious_fault+0x5/0x10
Code: 00 00 00 00 00 8b 44 24 10 89 d2 45 89 c9 48 89 44 24 10 8b 44 24 08 48 89 44 24 08 e9 d4 40 22 00 0f 1f 40 00 0f 1f 44 00 00 <0f> 0b 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 55 49 89 fd 41
RSP: 0018:ffffbf91c683bd00 EFLAGS: 00010246
RAX: 000061f040000000 RBX: ffff9e159c77bba0 RCX: ffff9e15a5c87000
RDX: 0000000665c87000 RSI: ffff9e15a5c87000 RDI: ffff9e159c77bba0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffff9e15a5c87000
R10: 0000000000000000 R11: fffff8f2d99721c0 R12: ffff9e159c77bba0
R13: ffffbf91c671d960 R14: ffff9e159c778000 R15: 0000000000000000
FS: 00007fa341cbe700(0000) GS:ffff9e15b7400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdd38356804 CR3: 00000006759de003 CR4: 00000000007606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
loaded_vmcs_init+0x4f/0xe0
alloc_loaded_vmcs+0x38/0xd0
vmx_create_vcpu+0xf7/0x600
kvm_vm_ioctl+0x5e9/0x980
? __switch_to_asm+0x40/0x70
? __switch_to_asm+0x34/0x70
? __switch_to_asm+0x40/0x70
? __switch_to_asm+0x34/0x70
? free_one_page+0x13f/0x4e0
do_vfs_ioctl+0xa4/0x630
ksys_ioctl+0x60/0x90
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x55/0x1c0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fa349b1ee5b
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/64a9b64d127e87b6920a97afde8e96ea76f6524e.1563413318.git.jpoimboe@redhat.com
The __raw_callee_save_*() functions have an ELF symbol size of zero,
which confuses objtool and other tools.
Fixes a bunch of warnings like the following:
arch/x86/xen/mmu_pv.o: warning: objtool: __raw_callee_save_xen_pte_val() is missing an ELF size annotation
arch/x86/xen/mmu_pv.o: warning: objtool: __raw_callee_save_xen_pgd_val() is missing an ELF size annotation
arch/x86/xen/mmu_pv.o: warning: objtool: __raw_callee_save_xen_make_pte() is missing an ELF size annotation
arch/x86/xen/mmu_pv.o: warning: objtool: __raw_callee_save_xen_make_pgd() is missing an ELF size annotation
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/afa6d49bb07497ca62e4fc3b27a2d0cece545b4e.1563413318.git.jpoimboe@redhat.com
Pull tracing updates from Steven Rostedt:
"The main changes in this release include:
- Add user space specific memory reading for kprobes
- Allow kprobes to be executed earlier in boot
The rest are mostly just various clean ups and small fixes"
* tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
tracing: Make trace_get_fields() global
tracing: Let filter_assign_type() detect FILTER_PTR_STRING
tracing: Pass type into tracing_generic_entry_update()
ftrace/selftest: Test if set_event/ftrace_pid exists before writing
ftrace/selftests: Return the skip code when tracing directory not configured in kernel
tracing/kprobe: Check registered state using kprobe
tracing/probe: Add trace_event_call accesses APIs
tracing/probe: Add probe event name and group name accesses APIs
tracing/probe: Add trace flag access APIs for trace_probe
tracing/probe: Add trace_event_file access APIs for trace_probe
tracing/probe: Add trace_event_call register API for trace_probe
tracing/probe: Add trace_probe init and free functions
tracing/uprobe: Set print format when parsing command
tracing/kprobe: Set print format right after parsed command
kprobes: Fix to init kprobes in subsys_initcall
tracepoint: Use struct_size() in kmalloc()
ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS
ftrace: Enable trampoline when rec count returns back to one
tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline
tracing: Make a separate config for trace event self tests
...
