Moving the code around broke this rare configuration.
Use this opportunity to finally call lapic reset from vcpu reset.
Reported-by: syzbot+fb7a33a4b6c35007a72b@syzkaller.appspotmail.com
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: 0b2e9904c1 ("KVM: x86: move LAPIC initialization after VMCS creation")
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Linux (among the others) has checks to make sure that certain features
aren't enabled on a certain family/model/stepping if the microcode version
isn't greater than or equal to a known good version.
By exposing the real microcode version, we're preventing buggy guests that
don't check that they are running virtualized (i.e., they should trust the
hypervisor) from disabling features that are effectively not buggy.
Suggested-by: Filippo Sironi <sironi@amazon.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Introduce kvm_get_msr_feature() to handle the msrs which are supported
by different vendors and sharing the same emulation logic.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
In order to determine if LFENCE is a serializing instruction on AMD
processors, MSR 0xc0011029 (MSR_F10H_DECFG) must be read and the state
of bit 1 checked. This patch will add support to allow a guest to
properly make this determination.
Add the MSR feature callback operation to svm.c and add MSR 0xc0011029
to the list of MSR-based features. If LFENCE is serializing, then the
feature is supported, allowing the hypervisor to set the value of the
MSR that guest will see. Support is also added to write (hypervisor only)
and read the MSR value for the guest. A write by the guest will result in
a #GP. A read by the guest will return the value as set by the host. In
this way, the support to expose the feature to the guest is controlled by
the hypervisor.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Provide a new KVM capability that allows bits within MSRs to be recognized
as features. Two new ioctls are added to the /dev/kvm ioctl routine to
retrieve the list of these MSRs and then retrieve their values. A kvm_x86_ops
callback is used to determine support for the listed MSR-based features.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[Tweaked documentation. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The separation of the cpu_entry_area from the fixmap missed the fact that
on 32bit non-PAE kernels the cpu_entry_area mapping might not be covered in
initial_page_table by the previous synchronizations.
This results in suspend/resume failures because 32bit utilizes initial page
table for resume. The absence of the cpu_entry_area mapping results in a
triple fault, aka. insta reboot.
With PAE enabled this works by chance because the PGD entry which covers
the fixmap and other parts incindentally provides the cpu_entry_area
mapping as well.
Synchronize the initial page table after setting up the cpu entry
area. Instead of adding yet another copy of the same code, move it to a
function and invoke it from the various places.
It needs to be investigated if the existing calls in setup_arch() and
setup_per_cpu_areas() can be replaced by the later invocation from
setup_cpu_entry_areas(), but that's beyond the scope of this fix.
Fixes: 92a0f81d89 ("x86/cpu_entry_area: Move it out of the fixmap")
Reported-by: Woody Suwalski <terraluna977@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Woody Suwalski <terraluna977@gmail.com>
Cc: William Grant <william.grant@canonical.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1802282137290.1392@nanos.tec.linutronix.de
Today the tty0 and hvc0 consoles are added as a preferred consoles for
pv domUs only. As this requires a boot parameter for getting dom0
messages per default, add them for dom0, too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
When the Intel Edison module is powered with 3.3V, the reboot command makes
the module stuck. If the module is powered at a greater voltage, like 4.4V
(as the Edison Mini Breakout board does), reboot works OK.
The official Intel Edison BSP sends the IPCMSG_COLD_RESET message to the
SCU by default. The IPCMSG_COLD_BOOT which is used by the upstream kernel
is only sent when explicitely selected on the kernel command line.
Use IPCMSG_COLD_RESET unconditionally which makes reboot work independent
of the power supply voltage.
[ tglx: Massaged changelog ]
Fixes: bda7b072de ("x86/platform/intel-mid: Implement power off sequence")
Signed-off-by: Sebastian Panceac <sebastian@resin.io>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1519810849-15131-1-git-send-email-sebastian@resin.io
Omitting suffixes from instructions in AT&T mode is bad practice when
operand size cannot be determined by the assembler from register
operands, and is likely going to be warned about by upstream gas in the
future (mine does already). Add the missing suffixes here. Note that for
64-bit this means some operations change from being 32-bit to 64-bit.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/5A93F98702000078001ABACC@prv-mh.provo.novell.com
Omitting suffixes from instructions in AT&T mode is bad practice when
operand size cannot be determined by the assembler from register
operands, and is likely going to be warned about by upstream gas in the
future (mine does already). Add the single missing suffix here.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/5A93F96902000078001ABAC8@prv-mh.provo.novell.com
As done in commit 3b3a371cc9 ("x86/debug: Use UD2 for WARN()"), this
switches to UD2 from UD0 to keep disassembly readable.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20180225165056.GA11719@beast
Unlike other archs flush_icache_range() is a noop on x64, therefore
remove the JIT's bpf_flush_icache() altogether since not needed.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull x86 fixes from Thomas Gleixner:
"Yet another pile of melted spectrum related changes:
- sanitize the array_index_nospec protection mechanism: Remove the
overengineered array_index_nospec_mask_check() magic and allow
const-qualified types as index to avoid temporary storage in a
non-const local variable.
- make the microcode loader more robust by properly propagating error
codes. Provide information about new feature bits after micro code
was updated so administrators can act upon.
- optimizations of the entry ASM code which reduce code footprint and
make the code simpler and faster.
- fix the {pmd,pud}_{set,clear}_flags() implementations to work
properly on paravirt kernels by removing the address translation
operations.
- revert the harmful vmexit_fill_RSB() optimization
- use IBRS around firmware calls
- teach objtool about retpolines and add annotations for indirect
jumps and calls.
- explicitly disable jumplabel patching in __init code and handle
patching failures properly instead of silently ignoring them.
- remove indirect paravirt calls for writing the speculation control
MSR as these calls are obviously proving the same attack vector
which is tried to be mitigated.
- a few small fixes which address build issues with recent compiler
and assembler versions"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR path as unlikely()
KVM/x86: Remove indirect MSR op calls from SPEC_CTRL
objtool, retpolines: Integrate objtool with retpoline support more closely
x86/entry/64: Simplify ENCODE_FRAME_POINTER
extable: Make init_kernel_text() global
jump_label: Warn on failed jump_label patching attempt
jump_label: Explicitly disable jump labels in __init code
x86/entry/64: Open-code switch_to_thread_stack()
x86/entry/64: Move ASM_CLAC to interrupt_entry()
x86/entry/64: Remove 'interrupt' macro
x86/entry/64: Move the switch_to_thread_stack() call to interrupt_entry()
x86/entry/64: Move ENTER_IRQ_STACK from interrupt macro to interrupt_entry
x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function
x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP
objtool: Add module specific retpoline rules
objtool: Add retpoline validation
objtool: Use existing global variables for options
x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute()
x86/boot, objtool: Annotate indirect jump in secondary_startup_64()
x86/paravirt, objtool: Annotate indirect calls
...
- optimization for the exitless interrupt support that was merged in 4.16-rc1
- improve the branch prediction blocking for nested KVM
- replace some jump tables with switch statements to improve expoline performance
- fixes for multiple epoch facility
ARM:
- fix the interaction of userspace irqchip VMs with in-kernel irqchip VMs
- make sure we can build 32-bit KVM/ARM with gcc-8.
x86:
- fixes for AMD SEV
- fixes for Intel nested VMX, emulated UMIP and a dump_stack() on VM startup
- fixes for async page fault migration
- small optimization to PV TLB flush (new in 4.16-rc1)
- syzkaller fixes
Generic:
- compiler warning fixes
- syzkaller fixes
- more improvements to the kvm_stat tool
Two more small Spectre fixes are going to reach you via Ingo.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"s390:
- optimization for the exitless interrupt support that was merged in 4.16-rc1
- improve the branch prediction blocking for nested KVM
- replace some jump tables with switch statements to improve expoline performance
- fixes for multiple epoch facility
ARM:
- fix the interaction of userspace irqchip VMs with in-kernel irqchip VMs
- make sure we can build 32-bit KVM/ARM with gcc-8.
x86:
- fixes for AMD SEV
- fixes for Intel nested VMX, emulated UMIP and a dump_stack() on VM startup
- fixes for async page fault migration
- small optimization to PV TLB flush (new in 4.16-rc1)
- syzkaller fixes
Generic:
- compiler warning fixes
- syzkaller fixes
- more improvements to the kvm_stat tool
Two more small Spectre fixes are going to reach you via Ingo"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (40 commits)
KVM: SVM: Fix SEV LAUNCH_SECRET command
KVM: SVM: install RSM intercept
KVM: SVM: no need to call access_ok() in LAUNCH_MEASURE command
include: psp-sev: Capitalize invalid length enum
crypto: ccp: Fix sparse, use plain integer as NULL pointer
KVM: X86: Avoid traversing all the cpus for pv tlb flush when steal time is disabled
x86/kvm: Make parse_no_xxx __init for kvm
KVM: x86: fix backward migration with async_PF
kvm: fix warning for non-x86 builds
kvm: fix warning for CONFIG_HAVE_KVM_EVENTFD builds
tools/kvm_stat: print 'Total' line for multiple events only
tools/kvm_stat: group child events indented after parent
tools/kvm_stat: separate drilldown and fields filtering
tools/kvm_stat: eliminate extra guest/pid selection dialog
tools/kvm_stat: mark private methods as such
tools/kvm_stat: fix debugfs handling
tools/kvm_stat: print error on invalid regex
tools/kvm_stat: fix crash when filtering out all non-child trace events
tools/kvm_stat: avoid 'is' for equality checks
tools/kvm_stat: use a more pythonic way to iterate over dictionaries
...
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-02-26
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Various improvements for BPF kselftests: i) skip unprivileged tests
when kernel.unprivileged_bpf_disabled sysctl knob is set, ii) count
the number of skipped tests from unprivileged, iii) when a test case
had an unexpected error then print the actual but also the unexpected
one for better comparison, from Joe.
2) Add a sample program for collecting CPU state statistics with regards
to how long the CPU resides in cstate and pstate levels. Based on
cpu_idle and cpu_frequency trace points, from Leo.
3) Various x64 BPF JIT optimizations to further shrink the generated
image size in order to make it more icache friendly. When tested on
the Cilium generated programs, image size reduced by approx 4-5% in
best case mainly due to how LLVM emits unsigned 32 bit constants,
from Daniel.
4) Improvements and fixes on the BPF sockmap sample programs: i) fix
the sockmap's Makefile to include nlattr.o for libbpf, ii) detach
the sock ops programs from the cgroup before exit, from Prashant.
5) Avoid including xdp.h in filter.h by just forward declaring the
struct xdp_rxq_info in filter.h, from Jesper.
6) Fix the BPF kselftests Makefile for cgroup_helpers.c by only declaring
it a dependency for test_dev_cgroup.c but not every other test case
where it is not needed, from Jesper.
7) Adjust rlimit RLIMIT_MEMLOCK for test_tcpbpf_user selftest since the
default is insufficient for creating the 'global_map' used in the
corresponding BPF program, from Yonghong.
8) Likewise, for the xdp_redirect sample, Tushar ran into the same when
invoking xdp_redirect and xdp_monitor at the same time, therefore
in order to have the sample generically work bump the limit here,
too. Fix from Tushar.
9) Avoid an unnecessary NULL check in BPF_CGROUP_RUN_PROG_INET_SOCK()
since sk is always guaranteed to be non-NULL, from Yafang.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull x86 fixes from Thomas Gleixner:
"A small set of fixes:
- UAPI data type correction for hyperv
- correct the cpu cores field in /proc/cpuinfo on CPU hotplug
- return proper error code in the resctrl file system failure path to
avoid silent subsequent failures
- correct a subtle accounting issue in the new vector allocation code
which went unnoticed for a while and caused suspend/resume
failures"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations
x86/topology: Fix function name in documentation
x86/intel_rdt: Fix incorrect returned value when creating rdgroup sub-directory in resctrl file system
x86/apic/vector: Handle vector release on CPU unplug correctly
genirq/matrix: Handle CPU offlining proper
x86/headers/UAPI: Use __u64 instead of u64 in <uapi/asm/hyperv.h>
Pull perf fix from Thomas Gleixner:
"A single commit which shuts up a bogus GCC-8 warning"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/oprofile: Fix bogus GCC-8 warning in nmi_setup()
Pull cleanup patchlet from Thomas Gleixner:
"A single commit removing a bunch of bogus double semicolons all over
the tree"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
treewide/trivial: Remove ';;$' typo noise
While it's rather cumbersome to reduce prologue for cBPF->eBPF
migrations wrt spill/fill for r15 which is callee saved register
due to bpf_error path in bpf_jit.S that is both used by migrations
as well as native eBPF, we can still trivially save 5 bytes in
prologue for the former since tail calls can never be used there.
cBPF->eBPF migrations also have their own custom prologue in BPF
asm that xors A and X reg anyway, so it's fine we skip this here.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a generic emit_mov_reg() helper in order to reuse it in BPF
multiplication to load the src into rax, we can save a few bytes
in alu32 while doing so.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Instead of unconditionally performing push/pop on rax/rdx
in case of multiplication, we can save a few bytes in case
of dest register being either BPF r0 (rax) or r3 (rdx)
since the result is written in there anyway.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
While analyzing some of the more complex BPF programs from Cilium,
I found that LLVM generally prefers to emit LD_IMM64 instead of MOV32
BPF instructions for loading unsigned 32-bit immediates into a
register. Given we cannot change the current/stable LLVM versions
that are already out there, lets optimize this case such that the
JIT prefers to emit 'mov %eax, imm32' over 'movabsq %rax, imm64'
whenever suitable in order to reduce the image size by 4-5 bytes per
such load in the typical case, reducing image size on some of the
bigger programs by up to 4%. emit_mov_imm32() and emit_mov_imm64()
have been added as helpers.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When we shift by one, we can use a different encoding where imm
is not explicitly needed, which saves 1 byte per such op.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The SEV LAUNCH_SECRET command fails with error code 'invalid param'
because we missed filling the guest and header system physical address
while issuing the command.
Fixes: 9f5b5b950a (KVM: SVM: Add support for SEV LAUNCH_SECRET command)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-kernel@vger.kernel.org
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
RSM instruction is used by the SMM handler to return from SMM mode.
Currently, rsm causes a #UD - which results in instruction fetch, decode,
and emulate. By installing the RSM intercept we can avoid the instruction
fetch since we know that #VMEXIT was due to rsm.
The patch is required for the SEV guest, because in case of SEV guest
memory is encrypted with guest-specific key and hypervisor will not
able to fetch the instruction bytes from the guest memory.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Using the access_ok() to validate the input before issuing the SEV
command does not buy us anything in this case. If userland is
giving us a garbage pointer then copy_to_user() will catch it when we try
to return the measurement.
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Fixes: 0d0736f763 (KVM: SVM: Add support for KVM_SEV_LAUNCH_MEASURE ...)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-kernel@vger.kernel.org
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Avoid traversing all the cpus for pv tlb flush when steal time
is disabled since pv tlb flush depends on the field in steal time
for shared data.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The early_param() is only called during kernel initialization, So Linux
marks the functions of it with __init macro to save memory.
But it forgot to mark the parse_no_kvmapf/stealacc/kvmclock_vsyscall,
So, Make them __init as well.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: rkrcmar@redhat.com
Cc: kvm@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: x86@kernel.org
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Guests on new hypersiors might set KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT
bit when enabling async_PF, but this bit is reserved on old hypervisors,
which results in a failure upon migration.
To avoid breaking different cases, we are checking for CPUID feature bit
before enabling the feature and nothing else.
Fixes: 52a5c155cf ("KVM: async_pf: Let guest support delivery of async_pf from guest mode")
Cc: <stable@vger.kernel.org>
Reviewed-by: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fix the following sparse warning by moving the prototype
of kvm_arch_mmu_notifier_invalidate_range() to linux/kvm_host.h .
CHECK arch/s390/kvm/../../../virt/kvm/kvm_main.c
arch/s390/kvm/../../../virt/kvm/kvm_main.c:138:13: warning: symbol 'kvm_arch_mmu_notifier_invalidate_range' was not declared. Should it be static?
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reported by syzkaller:
WARNING: CPU: 6 PID: 2434 at arch/x86/kvm/vmx.c:6660 handle_ept_misconfig+0x54/0x1e0 [kvm_intel]
CPU: 6 PID: 2434 Comm: repro_test Not tainted 4.15.0+ #4
RIP: 0010:handle_ept_misconfig+0x54/0x1e0 [kvm_intel]
Call Trace:
vmx_handle_exit+0xbd/0xe20 [kvm_intel]
kvm_arch_vcpu_ioctl_run+0xdaf/0x1d50 [kvm]
kvm_vcpu_ioctl+0x3e9/0x720 [kvm]
do_vfs_ioctl+0xa4/0x6a0
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x25/0x9c
The testcase creates a first thread to issue KVM_SMI ioctl, and then creates
a second thread to mmap and operate on the same vCPU. This triggers a race
condition when running the testcase with multiple threads. Sometimes one thread
exits with a triple fault while another thread mmaps and operates on the same
vCPU. Because CS=0x3000/IP=0x8000 is not mapped, accessing the SMI handler
results in an EPT misconfig. This patch fixes it by returning RET_PF_EMULATE
in kvm_handle_bad_page(), which will go on to cause an emulation failure and an
exit with KVM_EXIT_INTERNAL_ERROR.
Reported-by: syzbot+c1d9517cab094dae65e446c0c5b4de6c40f4dc58@syzkaller.appspotmail.com
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Although L2 is in halt state, it will be in the active state after
VM entry if the VM entry is vectoring according to SDM 26.6.2 Activity
State. Halting the vcpu here means the event won't be injected to L2
and this decision isn't reported to L1. Thus L0 drops an event that
should be injected to L2.
Cc: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On x86, special KVM memslots such as the TSS region have anonymous
memory mappings created on behalf of userspace, and these mappings are
removed when the VM is destroyed.
It is however possible for removing these mappings via vm_munmap() to
fail. This can most easily happen if the thread receives SIGKILL while
it's waiting to acquire ->mmap_sem. This triggers the 'WARN_ON(r < 0)'
in __x86_set_memory_region(). syzkaller was able to hit this, using
'exit()' to send the SIGKILL. Note that while the vm_munmap() failure
results in the mapping not being removed immediately, it is not leaked
forever but rather will be freed when the process exits.
It's not really possible to handle this failure properly, so almost
every other caller of vm_munmap() doesn't check the return value. It's
a limitation of having the kernel manage these mappings rather than
userspace.
So just remove the WARN_ON() so that users can't spam the kernel log
with this warning.
Fixes: f0d648bdf0 ("KVM: x86: map/unmap private slots in __x86_set_memory_region")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
L1 might want to use SECONDARY_EXEC_DESC, so we must not clear the VMCS
bit if UMIP is not being emulated.
We must still set the bit when emulating UMIP as the feature can be
passed to L2 where L0 will do the emulation and because L2 can change
CR4 without a VM exit, we should clear the bit if UMIP is disabled.
Fixes: 0367f205a3 ("KVM: vmx: add support for emulating UMIP")
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The initial reset of the local APIC is performed before the VMCS has been
created, but it tries to do a vmwrite:
vmwrite error: reg 810 value 4a00 (err 18944)
CPU: 54 PID: 38652 Comm: qemu-kvm Tainted: G W I 4.16.0-0.rc2.git0.1.fc28.x86_64 #1
Hardware name: Intel Corporation S2600CW/S2600CW, BIOS SE5C610.86B.01.01.0003.090520141303 09/05/2014
Call Trace:
vmx_set_rvi [kvm_intel]
vmx_hwapic_irr_update [kvm_intel]
kvm_lapic_reset [kvm]
kvm_create_lapic [kvm]
kvm_arch_vcpu_init [kvm]
kvm_vcpu_init [kvm]
vmx_create_vcpu [kvm_intel]
kvm_vm_ioctl [kvm]
Move it later, after the VMCS has been created.
Fixes: 4191db26b7 ("KVM: x86: Update APICv on APIC reset")
Cc: stable@vger.kernel.org
Cc: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull networking fixes from David Miller:
1) Fix TTL offset calculation in mac80211 mesh code, from Peter Oh.
2) Fix races with procfs in ipt_CLUSTERIP, from Cong Wang.
3) Memory leak fix in lpm_trie BPF map code, from Yonghong Song.
4) Need to use GFP_ATOMIC in BPF cpumap allocations, from Jason Wang.
5) Fix potential deadlocks in netfilter getsockopt() code paths, from
Paolo Abeni.
6) Netfilter stackpointer size checks really are needed to validate
user input, from Florian Westphal.
7) Missing timer init in x_tables, from Paolo Abeni.
8) Don't use WQ_MEM_RECLAIM in mac80211 hwsim, from Johannes Berg.
9) When an ibmvnic device is brought down then back up again, it can be
sent queue entries from a previous session, handle this properly
instead of crashing. From Thomas Falcon.
10) Fix TCP checksum on LRO buffers in mlx5e, from Gal Pressman.
11) When we are dumping filters in cls_api, the output SKB is empty, and
the filter we are dumping is too large for the space in the SKB, we
should return -EMSGSIZE like other netlink dump operations do.
Otherwise userland has no signal that is needs to increase the size
of its read buffer. From Roman Kapl.
12) Several XDP fixes for virtio_net, from Jesper Dangaard Brouer.
13) Module refcount leak in netlink when a dump start fails, from Jason
Donenfeld.
14) Handle sub-optimal GSO sizes better in TCP BBR congestion control,
from Eric Dumazet.
15) Releasing bpf per-cpu arraymaps can take a long time, add a
condtional scheduling point. From Eric Dumazet.
16) Implement retpolines for tail calls in x64 and arm64 bpf JITs. From
Daniel Borkmann.
17) Fix page leak in gianfar driver, from Andy Spencer.
18) Missed clearing of estimator scratch buffer, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
net_sched: gen_estimator: fix broken estimators based on percpu stats
gianfar: simplify FCS handling and fix memory leak
ipv6 sit: work around bogus gcc-8 -Wrestrict warning
macvlan: fix use-after-free in macvlan_common_newlink()
bpf, arm64: fix out of bounds access in tail call
bpf, x64: implement retpoline for tail call
rxrpc: Fix send in rxrpc_send_data_packet()
net: aquantia: Fix error handling in aq_pci_probe()
bpf: fix rcu lockdep warning for lpm_trie map_free callback
bpf: add schedule points in percpu arrays management
regulatory: add NUL to request alpha2
ibmvnic: Fix early release of login buffer
net/smc9194: Remove bogus CONFIG_MAC reference
net: ipv4: Set addr_type in hash_keys for forwarded case
tcp_bbr: better deal with suboptimal GSO
smsc75xx: fix smsc75xx_set_features()
netlink: put module reference if dump start fails
selftests/bpf/test_maps: exit child process without error in ENOMEM case
selftests/bpf: update gitignore with test_libbpf_open
selftests/bpf: tcpbpf_kern: use in6_* macros from glibc
..
Without this fix, /proc/cpuinfo will display an incorrect amount
of CPU cores, after bringing them offline and online again, as
exemplified below:
$ cat /proc/cpuinfo | grep cores
cpu cores : 4
cpu cores : 8
cpu cores : 8
cpu cores : 20
cpu cores : 4
cpu cores : 3
cpu cores : 2
cpu cores : 2
This patch fixes this by always zeroing the booted_cores variable
upon turning off a logical CPU.
Tested-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Samuel Neves <sneves@dei.uc.pt>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jgross@suse.com
Cc: luto@kernel.org
Cc: prarit@redhat.com
Cc: vkuznets@redhat.com
Link: http://lkml.kernel.org/r/20180221205036.5244-1-sneves@dei.uc.pt
Signed-off-by: Ingo Molnar <mingo@kernel.org>
vmx_vcpu_run() and svm_vcpu_run() are large functions, and giving
branch hints to the compiler can actually make a substantial cycle
difference by keeping the fast path contiguous in memory.
With this optimization, the retpoline-guest/retpoline-host case is
about 50 cycles faster.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: KarimAllah Ahmed <karahmed@amazon.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180222154318.20361-3-pbonzini@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Having a paravirt indirect call in the IBRS restore path is not a
good idea, since we are trying to protect from speculative execution
of bogus indirect branch targets. It is also slower, so use
native_wrmsrl() on the vmentry path too.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: KarimAllah Ahmed <karahmed@amazon.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: d28b387fb7
Link: http://lkml.kernel.org/r/20180222154318.20361-2-pbonzini@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If no monitoring feature is detected because all monitoring features are
disabled during boot time or there is no monitoring feature in hardware,
creating rdtgroup sub-directory by "mkdir" command reports error:
mkdir: cannot create directory ‘/sys/fs/resctrl/p1’: No such file or directory
But the sub-directory actually is generated and content is correct:
cpus cpus_list schemata tasks
The error is because rdtgroup_mkdir_ctrl_mon() returns non zero value after
the sub-directory is created and the returned value is reported as an error
to user.
Clear the returned value to report to user that the sub-directory is
actually created successfully.
Signed-off-by: Wang Hui <john.wanghui@huawei.com>
Signed-off-by: Zhang Yanfei <yanfei.zhang@huawei.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V Shankar <ravi.v.shankar@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vikas <vikas.shivappa@intel.com>
Cc: Xiaochen Shen <xiaochen.shen@intel.com>
Link: http://lkml.kernel.org/r/1519356363-133085-1-git-send-email-fenghua.yu@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a irq vector is replaced, then the previous vector is normally
released when the first interrupt happens on the new vector. If the target
CPU of the previous vector is already offline when the new vector is
installed, then the previous vector is silently discarded, which leads to
accounting issues causing suspend failures and other problems.
Adjust the logic so that the previous vector is freed in the underlying
matrix allocator to ensure that the accounting stays correct.
Fixes: 69cde0004a ("x86/vector: Use matrix allocator for vector assignment")
Reported-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180222112316.930791749@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Implement a retpoline [0] for the BPF tail call JIT'ing that converts
the indirect jump via jmp %rax that is used to make the long jump into
another JITed BPF image. Since this is subject to speculative execution,
we need to control the transient instruction sequence here as well
when CONFIG_RETPOLINE is set, and direct it into a pause + lfence loop.
The latter aligns also with what gcc / clang emits (e.g. [1]).
JIT dump after patch:
# bpftool p d x i 1
0: (18) r2 = map[id:1]
2: (b7) r3 = 0
3: (85) call bpf_tail_call#12
4: (b7) r0 = 2
5: (95) exit
With CONFIG_RETPOLINE:
# bpftool p d j i 1
[...]
33: cmp %edx,0x24(%rsi)
36: jbe 0x0000000000000072 |*
38: mov 0x24(%rbp),%eax
3e: cmp $0x20,%eax
41: ja 0x0000000000000072 |
43: add $0x1,%eax
46: mov %eax,0x24(%rbp)
4c: mov 0x90(%rsi,%rdx,8),%rax
54: test %rax,%rax
57: je 0x0000000000000072 |
59: mov 0x28(%rax),%rax
5d: add $0x25,%rax
61: callq 0x000000000000006d |+
66: pause |
68: lfence |
6b: jmp 0x0000000000000066 |
6d: mov %rax,(%rsp) |
71: retq |
72: mov $0x2,%eax
[...]
* relative fall-through jumps in error case
+ retpoline for indirect jump
Without CONFIG_RETPOLINE:
# bpftool p d j i 1
[...]
33: cmp %edx,0x24(%rsi)
36: jbe 0x0000000000000063 |*
38: mov 0x24(%rbp),%eax
3e: cmp $0x20,%eax
41: ja 0x0000000000000063 |
43: add $0x1,%eax
46: mov %eax,0x24(%rbp)
4c: mov 0x90(%rsi,%rdx,8),%rax
54: test %rax,%rax
57: je 0x0000000000000063 |
59: mov 0x28(%rax),%rax
5d: add $0x25,%rax
61: jmpq *%rax |-
63: mov $0x2,%eax
[...]
* relative fall-through jumps in error case
- plain indirect jump as before
[0] https://support.google.com/faqs/answer/7625886
[1] a31e654fa1
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
On i386, there are 2 types of PLTs, PIC and non-PIC. PIE and shared
objects must use PIC PLT. To use PIC PLT, you need to load
_GLOBAL_OFFSET_TABLE_ into EBX first. There is no need for that on
x86-64 since x86-64 uses PC-relative PLT.
On x86-64, for 32-bit PC-relative branches, we can generate PLT32
relocation, instead of PC32 relocation, which can also be used as
a marker for 32-bit PC-relative branches. Linker can always reduce
PLT32 relocation to PC32 if function is defined locally. Local
functions should use PC32 relocation. As far as Linux kernel is
concerned, R_X86_64_PLT32 can be treated the same as R_X86_64_PC32
since Linux kernel doesn't use PLT.
R_X86_64_PLT32 for 32-bit PC-relative branches has been enabled in
binutils master branch which will become binutils 2.31.
[ hjl is working on having better documentation on this all, but a few
more notes from him:
"PLT32 relocation is used as marker for PC-relative branches. Because
of EBX, it looks odd to generate PLT32 relocation on i386 when EBX
doesn't have GOT.
As for symbol resolution, PLT32 and PC32 relocations are almost
interchangeable. But when linker sees PLT32 relocation against a
protected symbol, it can resolved locally at link-time since it is
used on a branch instruction. Linker can't do that for PC32
relocation"
but for the kernel use, the two are basically the same, and this
commit gets things building and working with the current binutils
master - Linus ]
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On lkml suggestions were made to split up such trivial typo fixes into per subsystem
patches:
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -439,7 +439,7 @@ setup_uga32(void **uga_handle, unsigned long size, u32 *width, u32 *height)
struct efi_uga_draw_protocol *uga = NULL, *first_uga;
efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
unsigned long nr_ugas;
- u32 *handles = (u32 *)uga_handle;;
+ u32 *handles = (u32 *)uga_handle;
efi_status_t status = EFI_INVALID_PARAMETER;
int i;
This patch is the result of the following script:
$ sed -i 's/;;$/;/g' $(git grep -E ';;$' | grep "\.[ch]:" | grep -vwE 'for|ia64' | cut -d: -f1 | sort | uniq)
... followed by manual review to make sure it's all good.
Splitting this up is just crazy talk, let's get over with this and just do it.
Reported-by: Pavel Machek <pavel@ucw.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Disable retpoline validation in objtool if your compiler sucks, and otherwise
select the validation stuff for CONFIG_RETPOLINE=y (most builds would already
have it set due to ORC).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On 64-bit, the stack pointer is always aligned on interrupt, so instead
of setting the LSB of the pt_regs address, we can just add 1 to it.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180221024214.lhl5jfgw33c4vz3m@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Convert init_kernel_text() to a global function and use it in a few
places instead of manually comparing _sinittext and _einittext.
Note that kallsyms.h has a very similar function called
is_kernel_inittext(), but its end check is inclusive. I'm not sure
whether that's intentional behavior, so I didn't touch it.
Suggested-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Open-code the two instances which called switch_to_thread_stack(). This
allows us to remove the wrapper around DO_SWITCH_TO_THREAD_STACK.
While at it, update the UNWIND hint to reflect where the IRET frame is,
and update the commentary to reflect what we are actually doing here.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dan.j.williams@intel.com
Link: http://lkml.kernel.org/r/20180220210113.6725-7-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Moving ASM_CLAC to interrupt_entry means two instructions (addq / pushq
and call interrupt_entry) are not covered by it. However, it offers a
noticeable size reduction (-.2k):
text data bss dec hex filename
16882 0 0 16882 41f2 entry_64.o-orig
16623 0 0 16623 40ef entry_64.o
Suggested-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dan.j.williams@intel.com
Link: http://lkml.kernel.org/r/20180220210113.6725-6-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It is now trivial to call interrupt_entry() and then the actual worker.
Therefore, remove the interrupt macro and open code it all.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dan.j.williams@intel.com
Link: http://lkml.kernel.org/r/20180220210113.6725-5-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We can also move the CLD, SWAPGS, and the switch_to_thread_stack() call
to the interrupt_entry() helper function. As we do not want call depths
of two, convert switch_to_thread_stack() to a macro.
However, switch_to_thread_stack() has another user in entry_64_compat.S,
which currently expects it to be a function. To keep the code changes
in this patch minimal, create a wrapper function.
The switch to a macro means that there is some binary code duplication
if CONFIG_IA32_EMULATION=y is enabled. Therefore, the size reduction
differs whether CONFIG_IA32_EMULATION is enabled or not:
CONFIG_IA32_EMULATION=y (-0.13k):
text data bss dec hex filename
17158 0 0 17158 4306 entry_64.o-orig
17028 0 0 17028 4284 entry_64.o
CONFIG_IA32_EMULATION=n (-0.27k):
text data bss dec hex filename
17158 0 0 17158 4306 entry_64.o-orig
16882 0 0 16882 41f2 entry_64.o
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dan.j.williams@intel.com
Link: http://lkml.kernel.org/r/20180220210113.6725-4-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Moving the switch to IRQ stack from the interrupt macro to the helper
function requires some trickery: All ENTER_IRQ_STACK really cares about
is where the "original" stack -- meaning the GP registers etc. -- is
stored. Therefore, we need to offset the stored RSP value by 8 whenever
ENTER_IRQ_STACK is called from within a function. In such cases, and
after switching to the IRQ stack, we need to push the "original" return
address (i.e. the return address from the call to the interrupt entry
function) to the IRQ stack.
This trickery allows us to carve another .85k from the text size (it
would be more except for the additional unwind hints):
text data bss dec hex filename
18006 0 0 18006 4656 entry_64.o-orig
17158 0 0 17158 4306 entry_64.o
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dan.j.williams@intel.com
Link: http://lkml.kernel.org/r/20180220210113.6725-3-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The PUSH_AND_CLEAR_REGS macro is able to insert the GP registers
"above" the original return address. This allows us to move a sizeable
part of the interrupt entry macro to an interrupt entry helper function:
text data bss dec hex filename
21088 0 0 21088 5260 entry_64.o-orig
18006 0 0 18006 4656 entry_64.o
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dan.j.williams@intel.com
Link: http://lkml.kernel.org/r/20180220210113.6725-2-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
firmware_restrict_branch_speculation_*() recently started using
preempt_enable()/disable(), but those are relatively high level
primitives and cause build failures on some 32-bit builds.
Since we want to keep <asm/nospec-branch.h> low level, convert
them to macros to avoid header hell...
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arjan.van.de.ven@intel.com
Cc: bp@alien8.de
Cc: dave.hansen@intel.com
Cc: jmattson@google.com
Cc: karahmed@amazon.de
Cc: kvm@vger.kernel.org
Cc: pbonzini@redhat.com
Cc: rkrcmar@redhat.com
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
GCC-8 shows a warning for the x86 oprofile code that copies per-CPU
data from CPU 0 to all other CPUs, which when building a non-SMP
kernel turns into a memcpy() with identical source and destination
pointers:
arch/x86/oprofile/nmi_int.c: In function 'mux_clone':
arch/x86/oprofile/nmi_int.c:285:2: error: 'memcpy' source argument is the same as destination [-Werror=restrict]
memcpy(per_cpu(cpu_msrs, cpu).multiplex,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
per_cpu(cpu_msrs, 0).multiplex,
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sizeof(struct op_msr) * model->num_virt_counters);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/oprofile/nmi_int.c: In function 'nmi_setup':
arch/x86/oprofile/nmi_int.c:466:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict]
arch/x86/oprofile/nmi_int.c:470:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict]
I have analyzed a number of such warnings now: some are valid and the
GCC warning is welcome. Others turned out to be false-positives, and
GCC was changed to not warn about those any more. This is a corner case
that is a false-positive but the GCC developers feel it's better to keep
warning about it.
In this case, it seems best to work around it by telling GCC
a little more clearly that this code path is never hit with
an IS_ENABLED() configuration check.
Cc:stable as we also want old kernels to build cleanly with GCC-8.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Sebor <msebor@gcc.gnu.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <rric@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: oprofile-list@lists.sf.net
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180220205826.2008875-1-arnd@arndb.de
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84095
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This is boot code and thus Spectre-safe: we run this _way_ before userspace
comes along to have a chance to poison our branch predictor.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The objtool retpoline validation found this indirect jump. Seeing how
it's on CPU bringup before we run userspace it should be safe, annotate
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Paravirt emits indirect calls which get flagged by objtool retpoline
checks, annotate it away because all these indirect calls will be
patched out before we start userspace.
This patching happens through alternative_instructions() ->
apply_paravirt() -> pv_init_ops.patch() which will eventually end up
in paravirt_patch_default(). This function _will_ write direct
alternatives.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Annotate the indirect calls/jumps in the CALL_NOSPEC/JUMP_NOSPEC
alternatives.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This reverts commit 1dde7415e9. By putting
the RSB filling out of line and calling it, we waste one RSB slot for
returning from the function itself, which means one fewer actual function
call we can make if we're doing the Skylake abomination of call-depth
counting.
It also changed the number of RSB stuffings we do on vmexit from 32,
which was correct, to 16. Let's just stop with the bikeshedding; it
didn't actually *fix* anything anyway.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arjan.van.de.ven@intel.com
Cc: bp@alien8.de
Cc: dave.hansen@intel.com
Cc: jmattson@google.com
Cc: karahmed@amazon.de
Cc: kvm@vger.kernel.org
Cc: pbonzini@redhat.com
Cc: rkrcmar@redhat.com
Link: http://lkml.kernel.org/r/1519037457-7643-4-git-send-email-dwmw@amazon.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Omitting suffixes from instructions in AT&T mode is bad practice when
operand size cannot be determined by the assembler from register
operands, and is likely going to be warned about by upstream GAS in the
future (mine does already). Add the single missing suffix here.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5A8AF5F602000078001A9230@prv-mh.provo.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
BUG() doesn't always imply "no return", and hence should be followed by
a return statement even if that's obviously (to a human) unreachable.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5A8AF2AA02000078001A91E9@prv-mh.provo.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
df3405245a ("x86/asm: Add suffix macro for GEN_*_RMWcc()")
... introduced "suffix" RMWcc operations, adding bogus clobber specifiers:
For one, on x86 there's no point explicitly clobbering "cc".
In fact, with GCC properly fixed, this results in an overlap being detected by
the compiler between outputs and clobbers.
Furthermore it seems bad practice to me to have clobber specification
and use of the clobbered register(s) disconnected - it should rather be
at the invocation place of that GEN_{UN,BIN}ARY_SUFFIXED_RMWcc() macros
that the clobber is specified which this particular invocation needs.
Drop the "cc" clobber altogether and move the "cx" one to refcount.h.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5A8AF1F802000078001A91E1@prv-mh.provo.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This comment referred to a conditional call to kmemcheck_hide() that was
here until commit 4950276672 ("kmemcheck: remove annotations").
Now that kmemcheck has been removed, it doesn't make sense anymore.
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180219175039.253089-1-jannh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Just like pte_{set,clear}_flags() their PMD and PUD counterparts should
not do any address translation. This was outright wrong under Xen
(causing a dead boot with no useful output on "suitable" systems), and
produced needlessly more complicated code (even if just slightly) when
paravirt was enabled.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/5A8AF1BB02000078001A91C3@prv-mh.provo.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
... since u64 has a hidden header dependency that was not there before
using it (i.e. it breaks our VMM build).
Also, __u64 is the right way to expose data types through UAPI.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: devel@linuxdriverproject.org
Fixes: 93286261 ("x86/hyperv: Reenlightenment notifications support")
Link: http://lkml.kernel.org/r/1519112391-23773-1-git-send-email-karahmed@amazon.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 Kconfig fixes from Thomas Gleixner:
"Three patchlets to correct HIGHMEM64G and CMPXCHG64 dependencies in
Kconfig when CPU selections are explicitely set to M586 or M686"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/Kconfig: Explicitly enumerate i686-class CPUs in Kconfig
x86/Kconfig: Exclude i586-class CPUs lacking PAE support from the HIGHMEM64G Kconfig group
x86/Kconfig: Add missing i586-class CPUs to the X86_CMPXCHG64 Kconfig group
On some x86 CPU microarchitectures using 'xorq' to clear general-purpose
registers is slower than 'xorl'. As 'xorl' is sufficient to clear all
64 bits of these registers due to zero-extension [*], switch the x86
64-bit entry code to use 'xorl'.
No change in functionality and no change in code size.
[*] According to Intel 64 and IA-32 Architecture Software Developer's
Manual, section 3.4.1.1, the result of 32-bit operands are "zero-
extended to a 64-bit result in the destination general-purpose
register." The AMD64 Architecture Programmer’s Manual Volume 3,
Appendix B.1, describes the same behaviour.
Suggested-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180214175924.23065-3-linux@dominikbrodowski.net
[ Improved on the changelog a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Play a little trick in the generic PUSH_AND_CLEAR_REGS macro
to insert the GP registers "above" the original return address.
This allows us to (re-)insert the macro in error_entry() and
paranoid_entry() and to remove it from the idtentry macro. This
reduces the static footprint significantly:
text data bss dec hex filename
24307 0 0 24307 5ef3 entry_64.o-orig
20987 0 0 20987 51fb entry_64.o
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180214175924.23065-2-linux@dominikbrodowski.net
[ Small tweaks to comments. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With some microcode upgrades, new CPUID features can become visible on
the CPU. Check what the kernel has mirrored now and issue a warning
hinting at possible things the user/admin can do to make use of the
newly visible features.
Originally-by: Ashok Raj <ashok.raj@intel.com>
Tested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180216112640.11554-4-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a callback function which the microcode loader calls when microcode
has been updated to a newer revision. Do the callback only when no error
was encountered during loading.
Tested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180216112640.11554-3-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
... so that callers can know when microcode was updated and act
accordingly.
Tested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180216112640.11554-2-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The X86_P6_NOP config class leaves out many i686-class CPUs. Instead,
explicitly enumerate all these CPUs.
Using a configuration with M686 currently sets X86_MINIMUM_CPU_FAMILY=5
instead of the correct value of 6.
Booting on an i586 it will fail to generate the "This kernel
requires an i686 CPU, but only detected an i586 CPU" message and
intentional halt as expected. It will instead just silently hang
when it hits i686-specific instructions.
Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1518713696-11360-3-git-send-email-tedheadster@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
i586-class machines also lack support for Physical Address Extension (PAE),
so add them to the exclusion list.
Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1518713696-11360-2-git-send-email-tedheadster@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Several i586-class CPUs supporting this instruction are missing from
the X86_CMPXCHG64 config group.
Using a configuration with either M586TSC or M586MMX currently sets
X86_MINIMUM_CPU_FAMILY=4 instead of the correct value of 5.
Booting on an i486 it will fail to generate the "This kernel
requires an i586 CPU, but only detected an i486 CPU" message and
intentional halt as expected. It will instead just silently hang
when it hits i586-specific instructions.
The M586 CPU is not in this list because at least the Cyrix 5x86
lacks this instruction, and perhaps others.
Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1518713696-11360-1-git-send-email-tedheadster@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Ingo Molnar:
"Misc fixes all across the map:
- /proc/kcore vsyscall related fixes
- LTO fix
- build warning fix
- CPU hotplug fix
- Kconfig NR_CPUS cleanups
- cpu_has() cleanups/robustification
- .gitignore fix
- memory-failure unmapping fix
- UV platform fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pages
x86/error_inject: Make just_return_func() globally visible
x86/platform/UV: Fix GAM Range Table entries less than 1GB
x86/build: Add arch/x86/tools/insn_decoder_test to .gitignore
x86/smpboot: Fix uncore_pci_remove() indexing bug when hot-removing a physical CPU
x86/mm/kcore: Add vsyscall page to /proc/kcore conditionally
vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page
x86/Kconfig: Further simplify the NR_CPUS config
x86/Kconfig: Simplify NR_CPUS config
x86/MCE: Fix build warning introduced by "x86: do not use print_symbol()"
x86/cpufeature: Update _static_cpu_has() to use all named variables
x86/cpufeature: Reindent _static_cpu_has()
Pull x86 PTI and Spectre related fixes and updates from Ingo Molnar:
"Here's the latest set of Spectre and PTI related fixes and updates:
Spectre:
- Add entry code register clearing to reduce the Spectre attack
surface
- Update the Spectre microcode blacklist
- Inline the KVM Spectre helpers to get close to v4.14 performance
again.
- Fix indirect_branch_prediction_barrier()
- Fix/improve Spectre related kernel messages
- Fix array_index_nospec_mask() asm constraint
- KVM: fix two MSR handling bugs
PTI:
- Fix a paranoid entry PTI CR3 handling bug
- Fix comments
objtool:
- Fix paranoid_entry() frame pointer warning
- Annotate WARN()-related UD2 as reachable
- Various fixes
- Add Add Peter Zijlstra as objtool co-maintainer
Misc:
- Various x86 entry code self-test fixes
- Improve/simplify entry code stack frame generation and handling
after recent heavy-handed PTI and Spectre changes. (There's two
more WIP improvements expected here.)
- Type fix for cache entries
There's also some low risk non-fix changes I've included in this
branch to reduce backporting conflicts:
- rename a confusing x86_cpu field name
- de-obfuscate the naming of single-TLB flushing primitives"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
x86/entry/64: Fix CR3 restore in paranoid_exit()
x86/cpu: Change type of x86_cache_size variable to unsigned int
x86/spectre: Fix an error message
x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping
selftests/x86/mpx: Fix incorrect bounds with old _sigfault
x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]()
x86/speculation: Add <asm/msr-index.h> dependency
nospec: Move array_index_nospec() parameter checking into separate macro
x86/speculation: Fix up array_index_nospec_mask() asm constraint
x86/debug: Use UD2 for WARN()
x86/debug, objtool: Annotate WARN()-related UD2 as reachable
objtool: Fix segfault in ignore_unreachable_insn()
selftests/x86: Disable tests requiring 32-bit support on pure 64-bit systems
selftests/x86: Do not rely on "int $0x80" in single_step_syscall.c
selftests/x86: Do not rely on "int $0x80" in test_mremap_vdso.c
selftests/x86: Fix build bug caused by the 5lvl test which has been moved to the VM directory
selftests/x86/pkeys: Remove unused functions
selftests/x86: Clean up and document sscanf() usage
selftests/x86: Fix vDSO selftest segfault for vsyscall=none
x86/entry/64: Remove the unused 'icebp' macro
...
Josh Poimboeuf noticed the following bug:
"The paranoid exit code only restores the saved CR3 when it switches back
to the user GS. However, even in the kernel GS case, it's possible that
it needs to restore a user CR3, if for example, the paranoid exception
occurred in the syscall exit path between SWITCH_TO_USER_CR3_STACK and
SWAPGS."
Josh also confirmed via targeted testing that it's possible to hit this bug.
Fix the bug by also restoring CR3 in the paranoid_exit_no_swapgs branch.
The reason we haven't seen this bug reported by users yet is probably because
"paranoid" entry points are limited to the following cases:
idtentry double_fault do_double_fault has_error_code=1 paranoid=2
idtentry debug do_debug has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK
idtentry int3 do_int3 has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK
idtentry machine_check do_mce has_error_code=0 paranoid=1
Amongst those entry points only machine_check is one that will interrupt an
IRQS-off critical section asynchronously - and machine check events are rare.
The other main asynchronous entries are NMI entries, which can be very high-freq
with perf profiling, but they are special: they don't use the 'idtentry' macro but
are open coded and restore user CR3 unconditionally so don't have this bug.
Reported-and-tested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180214073910.boevmg65upbk3vqb@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, x86_cache_size is of type int, which makes no sense as we
will never have a valid cache size equal or less than 0. So instead of
initializing this variable to -1, it can perfectly be initialized to 0
and use it as an unsigned variable instead.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Addresses-Coverity-ID: 1464429
Link: http://lkml.kernel.org/r/20180213192208.GA26414@embeddedor.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If i == ARRAY_SIZE(mitigation_options) then we accidentally print
garbage from one space beyond the end of the mitigation_options[] array.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: KarimAllah Ahmed <karahmed@amazon.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Fixes: 9005c6834c ("x86/spectre: Simplify spectre_v2 command line parsing")
Link: http://lkml.kernel.org/r/20180214071416.GA26677@mwanda
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86_mask is a confusing name which is hard to associate with the
processor's stepping.
Additionally, correct an indent issue in lib/cpu.c.
Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com>
[ Updated it to more recent kernels. ]
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: tony.luck@intel.com
Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
flush_tlb_single() and flush_tlb_one() sound almost identical, but
they really mean "flush one user translation" and "flush one kernel
translation". Rename them to flush_tlb_one_user() and
flush_tlb_one_kernel() to make the semantics more obvious.
[ I was looking at some PTI-related code, and the flush-one-address code
is unnecessarily hard to understand because the names of the helpers are
uninformative. This came up during PTI review, but no one got around to
doing it. ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linux-MM <linux-mm@kvack.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/3303b02e3c3d049dc5235d5651e0ae6d29a34354.1517414378.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Allow the compiler to handle @size as an immediate value or memory
directly rather than allocating a register.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/151797010204.1289.1510000292250184993.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since the Intel SDM added an ModR/M byte to UD0 and binutils followed
that specification, we now cannot disassemble our kernel anymore.
This now means Intel and AMD disagree on the encoding of UD0. And instead
of playing games with additional bytes that are valid ModR/M and single
byte instructions (0xd6 for instance), simply use UD2 for both WARN() and
BUG().
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180208194406.GD25181@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
By default, objtool assumes that a UD2 is a dead end. This is mainly
because GCC 7+ sometimes inserts a UD2 when it detects a divide-by-zero
condition.
Now that WARN() is moving back to UD2, annotate the code after it as
reachable so objtool can follow the code flow.
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kbuild test robot <fengguang.wu@intel.com>
Link: http://lkml.kernel.org/r/0e483379275a42626ba8898117f918e1bf661e40.1518130694.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In the following commit:
ce0fa3e56a ("x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages")
... we added code to memory_failure() to unmap the page from the
kernel 1:1 virtual address space to avoid speculative access to the
page logging additional errors.
But memory_failure() may not always succeed in taking the page offline,
especially if the page belongs to the kernel. This can happen if
there are too many corrected errors on a page and either mcelog(8)
or drivers/ras/cec.c asks to take a page offline.
Since we remove the 1:1 mapping early in memory_failure(), we can
end up with the page unmapped, but still in use. On the next access
the kernel crashes :-(
There are also various debug paths that call memory_failure() to simulate
occurrence of an error. Since there is no actual error in memory, we
don't need to map out the page for those cases.
Revert most of the previous attempt and keep the solution local to
arch/x86/kernel/cpu/mcheck/mce.c. Unmap the page only when:
1) there is a real error
2) memory_failure() succeeds.
All of this only applies to 64-bit systems. 32-bit kernel doesn't map
all of memory into kernel space. It isn't worth adding the code to unmap
the piece that is mapped because nobody would run a 32-bit kernel on a
machine that has recoverable machine checks.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert (Persistent Memory) <elliott@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Cc: stable@vger.kernel.org #v4.14
Fixes: ce0fa3e56a ("x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With link time optimizations enabled, I get a link failure:
./ccLbOEHX.ltrans19.ltrans.o: In function `override_function_with_return':
<artificial>:(.text+0x7f3): undefined reference to `just_return_func'
Marking the symbol .globl makes it work as expected.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 540adea380 ("error-injection: Separate error-injection from kprobe")
Link: http://lkml.kernel.org/r/20180202145634.200291-3-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The latest UV platforms include the new ApachePass NVDIMMs into the
UV address space. This has introduced address ranges in the Global
Address Map Table that are less than the previous lowest range, which
was 2GB. Fix the address calculation so it accommodates address ranges
from bytes to exabytes.
Signed-off-by: Mike Travis <mike.travis@hpe.com>
Reviewed-by: Andrew Banman <andrew.banman@hpe.com>
Reviewed-by: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180205221503.190219903@stormcage.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The file was generated by make command and should not be in the source tree.
Signed-off-by: Progyan Bhattacharya <progyanb@acm.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a physical CPU is hot-removed, the following warning messages
are shown while the uncore device is removed in uncore_pci_remove():
WARNING: CPU: 120 PID: 5 at arch/x86/events/intel/uncore.c:988
uncore_pci_remove+0xf1/0x110
...
CPU: 120 PID: 5 Comm: kworker/u1024:0 Not tainted 4.15.0-rc8 #1
Workqueue: kacpi_hotplug acpi_hotplug_work_fn
...
Call Trace:
pci_device_remove+0x36/0xb0
device_release_driver_internal+0x145/0x210
pci_stop_bus_device+0x76/0xa0
pci_stop_root_bus+0x44/0x60
acpi_pci_root_remove+0x1f/0x80
acpi_bus_trim+0x54/0x90
acpi_bus_trim+0x2e/0x90
acpi_device_hotplug+0x2bc/0x4b0
acpi_hotplug_work_fn+0x1a/0x30
process_one_work+0x141/0x340
worker_thread+0x47/0x3e0
kthread+0xf5/0x130
When uncore_pci_remove() runs, it tries to get the package ID to
clear the value of uncore_extra_pci_dev[].dev[] by using
topology_phys_to_logical_pkg(). The warning messesages are
shown because topology_phys_to_logical_pkg() returns -1.
arch/x86/events/intel/uncore.c:
static void uncore_pci_remove(struct pci_dev *pdev)
{
...
phys_id = uncore_pcibus_to_physid(pdev->bus);
...
pkg = topology_phys_to_logical_pkg(phys_id); // returns -1
for (i = 0; i < UNCORE_EXTRA_PCI_DEV_MAX; i++) {
if (uncore_extra_pci_dev[pkg].dev[i] == pdev) {
uncore_extra_pci_dev[pkg].dev[i] = NULL;
break;
}
}
WARN_ON_ONCE(i >= UNCORE_EXTRA_PCI_DEV_MAX); // <=========== HERE!!
topology_phys_to_logical_pkg() tries to find
cpuinfo_x86->phys_proc_id that matches the phys_pkg argument.
arch/x86/kernel/smpboot.c:
int topology_phys_to_logical_pkg(unsigned int phys_pkg)
{
int cpu;
for_each_possible_cpu(cpu) {
struct cpuinfo_x86 *c = &cpu_data(cpu);
if (c->initialized && c->phys_proc_id == phys_pkg)
return c->logical_proc_id;
}
return -1;
}
However, the phys_proc_id was already set to 0 by remove_siblinginfo()
when the CPU was offlined.
So, topology_phys_to_logical_pkg() cannot find the correct
logical_proc_id and always returns -1.
As the result, uncore_pci_remove() calls WARN_ON_ONCE() and the warning
messages are shown.
What is worse is that the bogus 'pkg' index results in two bugs:
- We dereference uncore_extra_pci_dev[] with a negative index
- We fail to clean up a stale pointer in uncore_extra_pci_dev[][]
To fix these bugs, remove the clearing of ->phys_proc_id from remove_siblinginfo().
This should not cause any problems, because ->phys_proc_id is not
used after it is hot-removed and it is re-set while hot-adding.
Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yasu.isimatu@gmail.com
Cc: <stable@vger.kernel.org>
Fixes: 30bb981185 ("x86/topology: Avoid wasting 128k for package id array")
Link: http://lkml.kernel.org/r/ed738d54-0f01-b38b-b794-c31dc118c207@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The vsyscall page should be visible only if vsyscall=emulate/native when dumping /proc/kcore.
Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1518446694-21124-3-git-send-email-zhang.jia@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
df04abfd18 ("fs/proc/kcore.c: Add bounce buffer for ktext data")
... introduced a bounce buffer to work around CONFIG_HARDENED_USERCOPY=y.
However, accessing the vsyscall user page will cause an SMAP fault.
Replace memcpy() with copy_from_user() to fix this bug works, but adding
a common way to handle this sort of user page may be useful for future.
Currently, only vsyscall page requires KCORE_USER.
Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1518446694-21124-2-git-send-email-zhang.jia@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
That macro was touched around 2.5.8 times, judging by the full history
linux repo, but it was unused even then. Get rid of it already.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux@dominikbrodowski.net
Link: http://lkml.kernel.org/r/20180212201318.GD14640@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds