The kvmppc_tce_to_ua() helper is called from real and virtual modes
and it works fine as long as CONFIG_DEBUG_LOCKDEP is not enabled.
However if the lockdep debugging is on, the lockdep will most likely break
in kvm_memslots() because of srcu_dereference_check() so we need to use
PPC-own kvm_memslots_raw() which uses realmode safe
rcu_dereference_raw_notrace().
This creates a realmode copy of kvmppc_tce_to_ua() which replaces
kvm_memslots() with kvm_memslots_raw().
Since kvmppc_rm_tce_to_ua() becomes static and can only be used inside
HV KVM, this moves it earlier under CONFIG_KVM_BOOK3S_HV_POSSIBLE.
This moves truly virtual-mode kvmppc_tce_to_ua() to where it belongs and
drops the prmap parameter which was never used in the virtual mode.
Fixes: d3695aa4f4 ("KVM: PPC: Add support for multiple-TCE hcalls", 2016-02-15)
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
The trace_hardirqs_on() sets current->hardirqs_enabled and from here
the lockdep assumes interrupts are enabled although they are remain
disabled until the context switches to the guest. Consequent
srcu_read_lock() checks the flags in rcu_lock_acquire(), observes
disabled interrupts and prints a warning (see below).
This moves trace_hardirqs_on/off closer to __kvmppc_vcore_entry to
prevent lockdep from being confused.
DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
WARNING: CPU: 16 PID: 8038 at kernel/locking/lockdep.c:4128 check_flags.part.25+0x224/0x280
[...]
NIP [c000000000185b84] check_flags.part.25+0x224/0x280
LR [c000000000185b80] check_flags.part.25+0x220/0x280
Call Trace:
[c000003fec253710] [c000000000185b80] check_flags.part.25+0x220/0x280 (unreliable)
[c000003fec253780] [c000000000187ea4] lock_acquire+0x94/0x260
[c000003fec253840] [c00800001a1e9768] kvmppc_run_core+0xa60/0x1ab0 [kvm_hv]
[c000003fec253a10] [c00800001a1ed944] kvmppc_vcpu_run_hv+0x73c/0xec0 [kvm_hv]
[c000003fec253ae0] [c00800001a1095dc] kvmppc_vcpu_run+0x34/0x48 [kvm]
[c000003fec253b00] [c00800001a1056bc] kvm_arch_vcpu_ioctl_run+0x2f4/0x400 [kvm]
[c000003fec253b90] [c00800001a0f3618] kvm_vcpu_ioctl+0x460/0x850 [kvm]
[c000003fec253d00] [c00000000041c4f4] do_vfs_ioctl+0xe4/0x930
[c000003fec253db0] [c00000000041ce04] ksys_ioctl+0xc4/0x110
[c000003fec253e00] [c00000000041ce78] sys_ioctl+0x28/0x80
[c000003fec253e20] [c00000000000b5a4] system_call+0x5c/0x70
Instruction dump:
419e0034 3d220004 39291730 81290000 2f890000 409e0020 3c82ffc6 3c62ffc5
3884be70 386329c0 4bf6ea71 60000000 <0fe00000> 3c62ffc6 3863be90 4801273d
irq event stamp: 1025
hardirqs last enabled at (1025): [<c00800001a1e9728>] kvmppc_run_core+0xa20/0x1ab0 [kvm_hv]
hardirqs last disabled at (1024): [<c00800001a1e9358>] kvmppc_run_core+0x650/0x1ab0 [kvm_hv]
softirqs last enabled at (0): [<c0000000000f1210>] copy_process.isra.4.part.5+0x5f0/0x1d00
softirqs last disabled at (0): [<0000000000000000>] (null)
---[ end trace 31180adcc848993e ]---
possible reason: unannotated irqs-off.
irq event stamp: 1025
hardirqs last enabled at (1025): [<c00800001a1e9728>] kvmppc_run_core+0xa20/0x1ab0 [kvm_hv]
hardirqs last disabled at (1024): [<c00800001a1e9358>] kvmppc_run_core+0x650/0x1ab0 [kvm_hv]
softirqs last enabled at (0): [<c0000000000f1210>] copy_process.isra.4.part.5+0x5f0/0x1d00
softirqs last disabled at (0): [<0000000000000000>] (null)
Fixes: 8b24e69fc4 ("KVM: PPC: Book3S HV: Close race with testing for signals on guest entry", 2017-06-26)
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Implement a real mode handler for the H_CALL H_PAGE_INIT which can be
used to zero or copy a guest page. The page is defined to be 4k and must
be 4k aligned.
The in-kernel real mode handler halves the time to handle this H_CALL
compared to handling it in userspace for a hash guest.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Implement a virtual mode handler for the H_CALL H_PAGE_INIT which can be
used to zero or copy a guest page. The page is defined to be 4k and must
be 4k aligned.
The in-kernel handler halves the time to handle this H_CALL compared to
handling it in userspace for a radix guest.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
There is a hardware bug in some POWER9 processors where a treclaim in
fake suspend mode can cause an inconsistency in the XER[SO] bit across
the threads of a core, the workaround being to force the core into SMT4
when doing the treclaim.
The FAKE_SUSPEND bit (bit 10) in the PSSCR is used to control whether a
thread is in fake suspend or real suspend. The important difference here
being that thread reconfiguration is blocked in real suspend but not
fake suspend mode.
When we exit a guest which was in fake suspend mode, we force the core
into SMT4 while we do the treclaim in kvmppc_save_tm_hv().
However on the new exit path introduced with the function
kvmhv_run_single_vcpu() we restore the host PSSCR before calling
kvmppc_save_tm_hv() which means that if we were in fake suspend mode we
put the thread into real suspend mode when we clear the
PSSCR[FAKE_SUSPEND] bit. This means that we block thread reconfiguration
and the thread which is trying to get the core into SMT4 before it can
do the treclaim spins forever since it itself is blocking thread
reconfiguration. The result is that that core is essentially lost.
This results in a trace such as:
[ 93.512904] CPU: 7 PID: 13352 Comm: qemu-system-ppc Not tainted 5.0.0 #4
[ 93.512905] NIP: c000000000098a04 LR: c0000000000cc59c CTR: 0000000000000000
[ 93.512908] REGS: c000003fffd2bd70 TRAP: 0100 Not tainted (5.0.0)
[ 93.512908] MSR: 9000000302883033 <SF,HV,VEC,VSX,FP,ME,IR,DR,RI,LE,TM[SE]> CR: 22222444 XER: 00000000
[ 93.512914] CFAR: c000000000098a5c IRQMASK: 3
[ 93.512915] PACATMSCRATCH: 0000000000000001
[ 93.512916] GPR00: 0000000000000001 c000003f6cc1b830 c000000001033100 0000000000000004
[ 93.512928] GPR04: 0000000000000004 0000000000000002 0000000000000004 0000000000000007
[ 93.512930] GPR08: 0000000000000000 0000000000000004 0000000000000000 0000000000000004
[ 93.512932] GPR12: c000203fff7fc000 c000003fffff9500 0000000000000000 0000000000000000
[ 93.512935] GPR16: 2000000000300375 000000000000059f 0000000000000000 0000000000000000
[ 93.512951] GPR20: 0000000000000000 0000000000080053 004000000256f41f c000003f6aa88ef0
[ 93.512953] GPR24: c000003f6aa89100 0000000000000010 0000000000000000 0000000000000000
[ 93.512956] GPR28: c000003f9e9a0800 0000000000000000 0000000000000001 c000203fff7fc000
[ 93.512959] NIP [c000000000098a04] pnv_power9_force_smt4_catch+0x1b4/0x2c0
[ 93.512960] LR [c0000000000cc59c] kvmppc_save_tm_hv+0x40/0x88
[ 93.512960] Call Trace:
[ 93.512961] [c000003f6cc1b830] [0000000000080053] 0x80053 (unreliable)
[ 93.512965] [c000003f6cc1b8a0] [c00800001e9cb030] kvmhv_p9_guest_entry+0x508/0x6b0 [kvm_hv]
[ 93.512967] [c000003f6cc1b940] [c00800001e9cba44] kvmhv_run_single_vcpu+0x2dc/0xb90 [kvm_hv]
[ 93.512968] [c000003f6cc1ba10] [c00800001e9cc948] kvmppc_vcpu_run_hv+0x650/0xb90 [kvm_hv]
[ 93.512969] [c000003f6cc1bae0] [c00800001e8f620c] kvmppc_vcpu_run+0x34/0x48 [kvm]
[ 93.512971] [c000003f6cc1bb00] [c00800001e8f2d4c] kvm_arch_vcpu_ioctl_run+0x2f4/0x400 [kvm]
[ 93.512972] [c000003f6cc1bb90] [c00800001e8e3918] kvm_vcpu_ioctl+0x460/0x7d0 [kvm]
[ 93.512974] [c000003f6cc1bd00] [c0000000003ae2c0] do_vfs_ioctl+0xe0/0x8e0
[ 93.512975] [c000003f6cc1bdb0] [c0000000003aeb24] ksys_ioctl+0x64/0xe0
[ 93.512978] [c000003f6cc1be00] [c0000000003aebc8] sys_ioctl+0x28/0x80
[ 93.512981] [c000003f6cc1be20] [c00000000000b3a4] system_call+0x5c/0x70
[ 93.512983] Instruction dump:
[ 93.512986] 419dffbc e98c0000 2e8b0000 38000001 60000000 60000000 60000000 40950068
[ 93.512993] 392bffff 39400000 79290020 39290001 <7d2903a6> 60000000 60000000 7d235214
To fix this we preserve the PSSCR[FAKE_SUSPEND] bit until we call
kvmppc_save_tm_hv() which will mean the core can get into SMT4 and
perform the treclaim. Note kvmppc_save_tm_hv() clears the
PSSCR[FAKE_SUSPEND] bit again so there is no need to explicitly do that.
Fixes: 95a6432ce9 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests")
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
- Fix THP handling in the presence of pre-existing PTEs
- Honor request for PTE mappings even when THPs are available
- GICv4 performance improvement
- Take the srcu lock when writing to guest-controlled ITS data structures
- Reset the virtual PMU in preemptible context
- Various cleanups
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Merge tag 'kvmarm-fixes-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master
KVM/ARM fixes for 5.1
- Fix THP handling in the presence of pre-existing PTEs
- Honor request for PTE mappings even when THPs are available
- GICv4 performance improvement
- Take the srcu lock when writing to guest-controlled ITS data structures
- Reset the virtual PMU in preemptible context
- Various cleanups
Most (all?) x86 platforms provide a port IO based reset mechanism, e.g.
OUT 92h or CF9h. Userspace may emulate said mechanism, i.e. reset a
vCPU in response to KVM_EXIT_IO, without explicitly announcing to KVM
that it is doing a reset, e.g. Qemu jams vCPU state and resumes running.
To avoid corruping %rip after such a reset, commit 0967b7bf1c ("KVM:
Skip pio instruction when it is emulated, not executed") changed the
behavior of PIO handlers, i.e. today's "fast" PIO handling to skip the
instruction prior to exiting to userspace. Full emulation doesn't need
such tricks becase re-emulating the instruction will naturally handle
%rip being changed to point at the reset vector.
Updating %rip prior to executing to userspace has several drawbacks:
- Userspace sees the wrong %rip on the exit, e.g. if PIO emulation
fails it will likely yell about the wrong address.
- Single step exits to userspace for are effectively dropped as
KVM_EXIT_DEBUG is overwritten with KVM_EXIT_IO.
- Behavior of PIO emulation is different depending on whether it
goes down the fast path or the slow path.
Rather than skip the PIO instruction before exiting to userspace,
snapshot the linear %rip and cancel PIO completion if the current
value does not match the snapshot. For a 64-bit vCPU, i.e. the most
common scenario, the snapshot and comparison has negligible overhead
as VMCS.GUEST_RIP will be cached regardless, i.e. there is no extra
VMREAD in this case.
All other alternatives to snapshotting the linear %rip that don't
rely on an explicit reset announcenment suffer from one corner case
or another. For example, canceling PIO completion on any write to
%rip fails if userspace does a save/restore of %rip, and attempting to
avoid that issue by canceling PIO only if %rip changed then fails if PIO
collides with the reset %rip. Attempting to zero in on the exact reset
vector won't work for APs, which means adding more hooks such as the
vCPU's MP_STATE, and so on and so forth.
Checking for a linear %rip match technically suffers from corner cases,
e.g. userspace could theoretically rewrite the underlying code page and
expect a different instruction to execute, or the guest hardcodes a PIO
reset at 0xfffffff0, but those are far, far outside of what can be
considered normal operation.
Fixes: 432baf60ee ("KVM: VMX: use kvm_fast_pio_in for handling IN I/O")
Cc: <stable@vger.kernel.org>
Reported-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When userspace initializes guest vCPUs it may want to zero all supported
MSRs including Hyper-V related ones including HV_X64_MSR_STIMERn_CONFIG/
HV_X64_MSR_STIMERn_COUNT. With commit f3b138c5d8 ("kvm/x86: Update SynIC
timers on guest entry only") we began doing stimer_mark_pending()
unconditionally on every config change.
The issue I'm observing manifests itself as following:
- Qemu writes 0 to STIMERn_{CONFIG,COUNT} MSRs and marks all stimers as
pending in stimer_pending_bitmap, arms KVM_REQ_HV_STIMER;
- kvm_hv_has_stimer_pending() starts returning true;
- kvm_vcpu_has_events() starts returning true;
- kvm_arch_vcpu_runnable() starts returning true;
- when kvm_arch_vcpu_ioctl_run() gets into
(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED) case:
- kvm_vcpu_block() gets in 'kvm_vcpu_check_block(vcpu) < 0' and returns
immediately, avoiding normal wait path;
- -EAGAIN is returned from kvm_arch_vcpu_ioctl_run() immediately forcing
userspace to retry.
So instead of normal wait path we get a busy loop on all secondary vCPUs
before they get INIT signal. This seems to be undesirable, especially given
that this happens even when Hyper-V extensions are not used.
Generally, it seems to be pointless to mark an stimer as pending in
stimer_pending_bitmap and arm KVM_REQ_HV_STIMER as the only thing
kvm_hv_process_stimers() will do is clear the corresponding bit. We may
just not mark disabled timers as pending instead.
Fixes: f3b138c5d8 ("kvm/x86: Update SynIC timers on guest entry only")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since MSR_IA32_ARCH_CAPABILITIES is emualted unconditionally even if
host doesn't suppot it. We should move it to array emulated_msrs from
arry msrs_to_save, to report to userspace that guest support this msr.
Signed-off-by: Xiaoyao Li <xiaoyao.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The CPUID flag ARCH_CAPABILITIES is unconditioinally exposed to host
userspace for all x86 hosts, i.e. KVM advertises ARCH_CAPABILITIES
regardless of hardware support under the pretense that KVM fully
emulates MSR_IA32_ARCH_CAPABILITIES. Unfortunately, only VMX hosts
handle accesses to MSR_IA32_ARCH_CAPABILITIES (despite KVM_GET_MSRS
also reporting MSR_IA32_ARCH_CAPABILITIES for all hosts).
Move the MSR_IA32_ARCH_CAPABILITIES handling to common x86 code so
that it's emulated on AMD hosts.
Fixes: 1eaafe91a0 ("kvm: x86: IA32_ARCH_CAPABILITIES is always supported")
Cc: stable@vger.kernel.org
Reported-by: Xiaoyao Li <xiaoyao.li@linux.intel.com>
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Replace kvm_flush_remote_tlbs with kvm_flush_remote_tlbs_with_address
in slot_handle_level_range. When range based flushes are not enabled
kvm_flush_remote_tlbs_with_address falls back to kvm_flush_remote_tlbs.
This changes the behavior of many functions that indirectly use
slot_handle_level_range, iff the range based flushes are enabled. The
only potential problem I see with this is that kvm->tlbs_dirty will be
cleared less often, however the only caller of slot_handle_level_range that
checks tlbs_dirty is kvm_mmu_notifier_invalidate_range_start which
checks it and does a kvm_flush_remote_tlbs after calling
kvm_unmap_hva_range anyway.
Tested: Ran all kvm-unit-tests on a Intel Haswell machine with and
without this patch. The patch introduced no new failures.
Signed-off-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
I do not see any consistency about headers_install of <linux/kvm_para.h>
and <asm/kvm_para.h>.
According to my analysis of Linux 5.1-rc1, there are 3 groups:
[1] Both <linux/kvm_para.h> and <asm/kvm_para.h> are exported
alpha, arm, hexagon, mips, powerpc, s390, sparc, x86
[2] <asm/kvm_para.h> is exported, but <linux/kvm_para.h> is not
arc, arm64, c6x, h8300, ia64, m68k, microblaze, nios2, openrisc,
parisc, sh, unicore32, xtensa
[3] Neither <linux/kvm_para.h> nor <asm/kvm_para.h> is exported
csky, nds32, riscv
This does not match to the actual KVM support. At least, [2] is
half-baked.
Nor do arch maintainers look like they care about this. For example,
commit 0add53713b ("microblaze: Add missing kvm_para.h to Kbuild")
exported <asm/kvm_para.h> to user-space in order to fix an in-kernel
build error.
We have two ways to make this consistent:
[A] export both <linux/kvm_para.h> and <asm/kvm_para.h> for all
architectures, irrespective of the KVM support
[B] Match the header export of <linux/kvm_para.h> and <asm/kvm_para.h>
to the KVM support
My first attempt was [A] because the code looks cleaner, but Paolo
suggested [B].
So, this commit goes with [B].
For most architectures, <asm/kvm_para.h> was moved to the kernel-space.
I changed include/uapi/linux/Kbuild so that it checks generated
asm/kvm_para.h as well as check-in ones.
After this commit, there will be two groups:
[1] Both <linux/kvm_para.h> and <asm/kvm_para.h> are exported
arm, arm64, mips, powerpc, s390, x86
[2] Neither <linux/kvm_para.h> nor <asm/kvm_para.h> is exported
alpha, arc, c6x, csky, h8300, hexagon, ia64, m68k, microblaze,
nds32, nios2, openrisc, parisc, riscv, sh, sparc, unicore32, xtensa
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* nr_mmu_pages would be non-zero only if kvm->arch.n_requested_mmu_pages is
non-zero.
* nr_mmu_pages is always non-zero, since kvm_mmu_calculate_mmu_pages()
never return zero.
Based on these two reasons, we can merge the two *if* clause and use the
return value from kvm_mmu_calculate_mmu_pages() directly. This simplify
the code and also eliminate the possibility for reader to believe
nr_mmu_pages would be zero.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
According to section "Checks on VMX Controls" in Intel SDM vol 3C, the
following check is performed on vmentry of L2 guests:
On processors that support Intel 64 architecture, the IA32_SYSENTER_ESP
field and the IA32_SYSENTER_EIP field must each contain a canonical
address.
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Errata#1096:
On a nested data page fault when CR.SMAP=1 and the guest data read
generates a SMAP violation, GuestInstrBytes field of the VMCB on a
VMEXIT will incorrectly return 0h instead the correct guest
instruction bytes .
Recommend Workaround:
To determine what instruction the guest was executing the hypervisor
will have to decode the instruction at the instruction pointer.
The recommended workaround can not be implemented for the SEV
guest because guest memory is encrypted with the guest specific key,
and instruction decoder will not be able to decode the instruction
bytes. If we hit this errata in the SEV guest then log the message
and request a guest shutdown.
Reported-by: Venkatesh Srinivas <venkateshs@google.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The cr4_pae flag is a bit of a misnomer, its purpose is really to track
whether the guest PTE that is being shadowed is a 4-byte entry or an
8-byte entry. Prior to supporting nested EPT, the size of the gpte was
reflected purely by CR4.PAE. KVM fudged things a bit for direct sptes,
but it was mostly harmless since the size of the gpte never mattered.
Now that a spte may be tracking an indirect EPT entry, relying on
CR4.PAE is wrong and ill-named.
For direct shadow pages, force the gpte_size to '1' as they are always
8-byte entries; EPT entries can only be 8-bytes and KVM always uses
8-byte entries for NPT and its identity map (when running with EPT but
not unrestricted guest).
Likewise, nested EPT entries are always 8-bytes. Nested EPT presents a
unique scenario as the size of the entries are not dictated by CR4.PAE,
but neither is the shadow page a direct map. To handle this scenario,
set cr0_wp=1 and smap_andnot_wp=1, an otherwise impossible combination,
to denote a nested EPT shadow page. Use the information to avoid
incorrectly zapping an unsync'd indirect page in __kvm_sync_page().
Providing a consistent and accurate gpte_size fixes a bug reported by
Vitaly where fast_cr3_switch() always fails when switching from L2 to
L1 as kvm_mmu_get_page() would force role.cr4_pae=0 for direct pages,
whereas kvm_calc_mmu_role_common() would set it according to CR4.PAE.
Fixes: 7dcd575520 ("x86/kvm/mmu: check if tdp/shadow MMU reconfiguration is needed")
Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Explicitly zero out quadrant and invalid instead of inheriting them from
the root_mmu. Functionally, this patch is a nop as we (should) never
set quadrant for a direct mapped (EPT) root_mmu and nested EPT is only
allowed if EPT is used for L1, and the root_mmu will never be invalid at
this point.
Explicitly setting flags sets the stage for repurposing the legacy
paging bits in role, e.g. nxe, cr0_wp, and sm{a,e}p_andnot_wp, at which
point 'smm' would be the only flag to be inherited from root_mmu.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull x86 fixes from Thomas Gleixner:
"A set of x86 fixes:
- Prevent potential NULL pointer dereferences in the HPET and HyperV
code
- Exclude the GART aperture from /proc/kcore to prevent kernel
crashes on access
- Use the correct macros for Cyrix I/O on Geode processors
- Remove yet another kernel address printk leak
- Announce microcode reload completion as requested by quite some
people. Microcode loading has become popular recently.
- Some 'Make Clang' happy fixlets
- A few cleanups for recently added code"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/gart: Exclude GART aperture from kcore
x86/hw_breakpoints: Make default case in hw_breakpoint_arch_parse() return an error
x86/mm/pti: Make local symbols static
x86/cpu/cyrix: Remove {get,set}Cx86_old macros used for Cyrix processors
x86/cpu/cyrix: Use correct macros for Cyrix calls on Geode processors
x86/microcode: Announce reload operation's completion
x86/hyperv: Prevent potential NULL pointer dereference
x86/hpet: Prevent potential NULL pointer dereference
x86/lib: Fix indentation issue, remove extra tab
x86/boot: Restrict header scope to make Clang happy
x86/mm: Don't leak kernel addresses
x86/cpufeature: Fix various quality problems in the <asm/cpu_device_hd.h> header
Pull irq fixes from Thomas Gleixner:
"A set of fixes for the interrupt subsystem:
- Remove secondary GIC support on systems w/o device-tree support
- A set of small fixlets in various irqchip drivers
- static and fall-through annotations
- Kernel doc and typo fixes"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Mark expected switch case fall-through
genirq/devres: Remove excess parameter from kernel doc
irqchip/irq-mvebu-sei: Make mvebu_sei_ap806_caps static
irqchip/mbigen: Don't clear eventid when freeing an MSI
irqchip/stm32: Don't set rising configuration registers at init
irqchip/stm32: Don't clear rising/falling config registers at init
dt-bindings: irqchip: renesas-irqc: Document r8a774c0 support
irqchip/mmp: Make mmp_irq_domain_ops static
irqchip/brcmstb-l2: Make two init functions static
genirq: Fix typo in comment of IRQD_MOVE_PCNTXT
irqchip/gic-v3-its: Fix comparison logic in lpi_range_cmp
irqchip/gic: Drop support for secondary GIC in non-DT systems
irqchip/imx-irqsteer: Fix of_property_read_u32() error handling
On machines where the GART aperture is mapped over physical RAM,
/proc/kcore contains the GART aperture range. Accessing the GART range via
/proc/kcore results in a kernel crash.
vmcore used to have the same issue, until it was fixed with commit
2a3e83c6f9 ("x86/gart: Exclude GART aperture from vmcore")', leveraging
existing hook infrastructure in vmcore to let /proc/vmcore return zeroes
when attempting to read the aperture region, and so it won't read from the
actual memory.
Apply the same workaround for kcore. First implement the same hook
infrastructure for kcore, then reuse the hook functions introduced in the
previous vmcore fix. Just with some minor adjustment, rename some functions
for more general usage, and simplify the hook infrastructure a bit as there
is no module usage yet.
Suggested-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jiri Bohac <jbohac@suse.cz>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Dave Young <dyoung@redhat.com>
Link: https://lkml.kernel.org/r/20190308030508.13548-1-kasong@redhat.com
One fix for a boot failure on 32-bit, introduced during the merge window.
A fix for our handling of CLOCK_MONOTONIC in the 64-bit VDSO. Changing the wall
clock across the Y2038 boundary could cause CLOCK_MONOTONIC to jump forward and
backward.
Our spectre_v2 reporting was a bit confusing due to a bug I introduced. On some
systems it was reporting that the count cache was disabled and also that we were
flushing the count cache on context switch. Only the former is true, and given
that the count cache is disabled it doesn't make any sense to flush it. No one
reported it, so presumably the presence of any mitigation is all people check
for.
Finally a small build fix for zsmalloc on 32-bit.
Thanks to:
Ben Hutchings, Christophe Leroy, Diana Craciun, Guenter Roeck, Michael Neuling.
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Merge tag 'powerpc-5.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"One fix for a boot failure on 32-bit, introduced during the merge
window.
A fix for our handling of CLOCK_MONOTONIC in the 64-bit VDSO. Changing
the wall clock across the Y2038 boundary could cause CLOCK_MONOTONIC
to jump forward and backward.
Our spectre_v2 reporting was a bit confusing due to a bug I
introduced. On some systems it was reporting that the count cache was
disabled and also that we were flushing the count cache on context
switch. Only the former is true, and given that the count cache is
disabled it doesn't make any sense to flush it. No one reported it, so
presumably the presence of any mitigation is all people check for.
Finally a small build fix for zsmalloc on 32-bit.
Thanks to: Ben Hutchings, Christophe Leroy, Diana Craciun, Guenter
Roeck, Michael Neuling"
* tag 'powerpc-5.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/security: Fix spectre_v2 reporting
powerpc/mm: Only define MAX_PHYSMEM_BITS in SPARSEMEM configurations
powerpc/6xx: fix setup and use of SPRN_SPRG_PGDIR for hash32
powerpc/vdso64: Fix CLOCK_MONOTONIC inconsistencies across Y2038
When building with -Wsometimes-uninitialized, Clang warns:
arch/x86/kernel/hw_breakpoint.c:355:2: warning: variable 'align' is used
uninitialized whenever switch default is taken
[-Wsometimes-uninitialized]
The default cannot be reached because arch_build_bp_info() initializes
hw->len to one of the specified cases. Nevertheless the warning is valid
and returning -EINVAL makes sure that this cannot be broken by future
modifications.
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: clang-built-linux@googlegroups.com
Link: https://github.com/ClangBuiltLinux/linux/issues/392
Link: https://lkml.kernel.org/r/20190307212756.4648-1-natechancellor@gmail.com
With 'make C=2 W=1', sparse and gcc both complain:
CHECK arch/x86/mm/pti.c
arch/x86/mm/pti.c:84:3: warning: symbol 'pti_mode' was not declared. Should it be static?
arch/x86/mm/pti.c:605:6: warning: symbol 'pti_set_kernel_image_nonglobal' was not declared. Should it be static?
CC arch/x86/mm/pti.o
arch/x86/mm/pti.c:605:6: warning: no previous prototype for 'pti_set_kernel_image_nonglobal' [-Wmissing-prototypes]
605 | void pti_set_kernel_image_nonglobal(void)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pti_set_kernel_image_nonglobal() is only used locally. 'pti_mode' exists in
drivers/hwtracing/intel_th/pti.c as well, but it's a completely unrelated
local (static) symbol.
Make both static.
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/27680.1552376873@turing-police
be queued during the merging window but, due to conflicts, it was
deferred post -rc1
- Extend the Fujitsu erratum 010001 workaround to A64FX v1r0
- Whitelist HiSilicon Taishan v110 CPUs as not susceptible to Meltdown
- Export save_stack_trace_regs()
- Remove obsolete selection of MULTI_IRQ_HANDLER
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
"Mostly fixes apart from the kprobe blacklist checking which was
deferred because of conflicting with a fix merged after I pinned the
arm64 for-next/core branch (f2b3d8566d "arm64: kprobe: Always
blacklist the KVM world-switch code").
Summary:
- Update the kprobe blacklist checking for arm64. This was supposed
to be queued during the merging window but, due to conflicts, it
was deferred post -rc1
- Extend the Fujitsu erratum 010001 workaround to A64FX v1r0
- Whitelist HiSilicon Taishan v110 CPUs as not susceptible to
Meltdown
- Export save_stack_trace_regs()
- Remove obsolete selection of MULTI_IRQ_HANDLER"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: remove obsolete selection of MULTI_IRQ_HANDLER
arm64: kpti: Whitelist HiSilicon Taishan v110 CPUs
arm64: Add MIDR encoding for HiSilicon Taishan CPUs
arm64/stacktrace: Export save_stack_trace_regs()
arm64: apply workaround on A64FX v1r0
arm64: kprobes: Use arch_populate_kprobe_blacklist()
arm64: kprobes: Move exception_text check in blacklist
arm64: kprobes: Remove unneeded RODATA check
arm64: kprobes: Move extable address check into arch_prepare_kprobe()
There are comments in processor-cyrix.h advising you to _not_ make calls
using the deprecated macros in this style:
setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);
This is because it expands the macro into a non-functioning calling
sequence. The calling order must be:
outb(CX86_CCR2, 0x22);
inb(0x23);
From the comments:
* When using the old macros a line like
* setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
* gets expanded to:
* do {
* outb((CX86_CCR2), 0x22);
* outb((({
* outb((CX86_CCR2), 0x22);
* inb(0x23);
* }) | 0x88), 0x23);
* } while (0);
The new macros fix this problem, so use them instead. Tested on an
actual Geode processor.
Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: luto@kernel.org
Link: https://lkml.kernel.org/r/1552596361-8967-2-git-send-email-tedheadster@gmail.com
By popular demand, issue a single line to dmesg after the reload
operation completes to let the user know that a reload has at least been
attempted.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190313110022.8229-1-bp@alien8.de
The page allocation in hv_cpu_init() can fail, but the code does not
have a check for that.
Add a check and return -ENOMEM when the allocation fails.
[ tglx: Massaged changelog ]
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Acked-by: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: pakki001@umn.edu
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-hyperv@vger.kernel.org
Link: https://lkml.kernel.org/r/20190314054651.1315-1-kjlu@umn.edu
hpet_virt_address may be NULL when ioremap_nocache fail, but the code lacks
a check.
Add a check to prevent NULL pointer dereference.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kjlu@umn.edu
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Roland Dreier <roland@purestorage.com>
Link: https://lkml.kernel.org/r/20190319021958.17275-1-pakki001@umn.edu
The inclusion of <linux/kernel.h> was causing issue as the definition of
__arch_hweight64 from arch/x86/include/asm/arch_hweight.h eventually gets
included. The definition is problematic when compiled with -m16 (all code
in arch/x86/boot/ is) as the "D" inline assembly constraint is rejected
by both compilers when passed an argument of type long long (regardless
of signedness, anything smaller is fine).
Because GCC performs inlining before semantic analysis, and
__arch_hweight64 is dead in this translation unit, GCC does not report
any issues at compile time. Clang does the semantic analysis in the
front end, before inlining (run in the middle) can determine the code is
dead. I consider this another case of PR33587, which I think we can do
more work to solve.
It turns out that arch/x86/boot/string.c doesn't actually need
linux/kernel.h, simply linux/limits.h and linux/compiler.h.
Suggested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: bp@alien8.de
Cc: niravd@google.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Link: https://bugs.llvm.org/show_bug.cgi?id=33587
Link: https://github.com/ClangBuiltLinux/linux/issues/347
Link: https://lkml.kernel.org/r/20190314221458.83047-1-ndesaulniers@google.com
When I updated the spectre_v2 reporting to handle software count cache
flush I got the logic wrong when there's no software count cache
enabled at all.
The result is that on systems with the software count cache flush
disabled we print:
Mitigation: Indirect branch cache disabled, Software count cache flush
Which correctly indicates that the count cache is disabled, but
incorrectly says the software count cache flush is enabled.
The root of the problem is that we are trying to handle all
combinations of options. But we know now that we only expect to see
the software count cache flush enabled if the other options are false.
So split the two cases, which simplifies the logic and fixes the bug.
We were also missing a space before "(hardware accelerated)".
The result is we see one of:
Mitigation: Indirect branch serialisation (kernel only)
Mitigation: Indirect branch cache disabled
Mitigation: Software count cache flush
Mitigation: Software count cache flush (hardware accelerated)
Fixes: ee13cb249f ("powerpc/64s: Add support for software count cache flush")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The arm64 config selects MULTI_IRQ_HANDLER, which was renamed to
GENERIC_IRQ_MULTI_HANDLER by commit 4c301f9b6a ("ARM: Convert
to GENERIC_IRQ_MULTI_HANDLER"). The 'new' option is already
selected, so just remove the obsolete entry.
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We rely on the mmu_notifier call backs to handle the split/merge
of huge pages and thus we are guaranteed that, while creating a
block mapping, either the entire block is unmapped at stage2 or it
is missing permission.
However, we miss a case where the block mapping is split for dirty
logging case and then could later be made block mapping, if we cancel the
dirty logging. This not only creates inconsistent TLB entries for
the pages in the the block, but also leakes the table pages for
PMD level.
Handle this corner case for the huge mappings at stage2 by
unmapping the non-huge mapping for the block. This could potentially
release the upper level table. So we need to restart the table walk
once we unmap the range.
Fixes : ad361f093c ("KVM: ARM: Support hugetlbfs backed huge pages")
Reported-by: Zheng Xiang <zhengxiang9@huawei.com>
Cc: Zheng Xiang <zhengxiang9@huawei.com>
Cc: Zenghui Yu <yuzenghui@huawei.com>
Cc: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
MAX_PHYSMEM_BITS only needs to be defined if CONFIG_SPARSEMEM is
enabled, and that was the case before commit 4ffe713b75
("powerpc/mm: Increase the max addressable memory to 2PB").
On 32-bit systems, where CONFIG_SPARSEMEM is not enabled, we now
define it as 46. That is larger than the real number of physical
address bits, and breaks calculations in zsmalloc:
mm/zsmalloc.c:130:49: warning: right shift count is negative
MAX(32, (ZS_MAX_PAGES_PER_ZSPAGE << PAGE_SHIFT >> OBJ_INDEX_BITS))
^~
...
mm/zsmalloc.c:253:21: error: variably modified 'size_class' at file scope
struct size_class *size_class[ZS_SIZE_CLASSES];
^~~~~~~~~~
Fixes: 4ffe713b75 ("powerpc/mm: Increase the max addressable memory to 2PB")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When halting a guest, QEMU flushes the virtual ITS caches, which
amounts to writing to the various tables that the guest has allocated.
When doing this, we fail to take the srcu lock, and the kernel
shouts loudly if running a lockdep kernel:
[ 69.680416] =============================
[ 69.680819] WARNING: suspicious RCU usage
[ 69.681526] 5.1.0-rc1-00008-g600025238f51-dirty #18 Not tainted
[ 69.682096] -----------------------------
[ 69.682501] ./include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage!
[ 69.683225]
[ 69.683225] other info that might help us debug this:
[ 69.683225]
[ 69.683975]
[ 69.683975] rcu_scheduler_active = 2, debug_locks = 1
[ 69.684598] 6 locks held by qemu-system-aar/4097:
[ 69.685059] #0: 0000000034196013 (&kvm->lock){+.+.}, at: vgic_its_set_attr+0x244/0x3a0
[ 69.686087] #1: 00000000f2ed935e (&its->its_lock){+.+.}, at: vgic_its_set_attr+0x250/0x3a0
[ 69.686919] #2: 000000005e71ea54 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[ 69.687698] #3: 00000000c17e548d (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[ 69.688475] #4: 00000000ba386017 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[ 69.689978] #5: 00000000c2c3c335 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[ 69.690729]
[ 69.690729] stack backtrace:
[ 69.691151] CPU: 2 PID: 4097 Comm: qemu-system-aar Not tainted 5.1.0-rc1-00008-g600025238f51-dirty #18
[ 69.691984] Hardware name: rockchip evb_rk3399/evb_rk3399, BIOS 2019.04-rc3-00124-g2feec69fb1 03/15/2019
[ 69.692831] Call trace:
[ 69.694072] lockdep_rcu_suspicious+0xcc/0x110
[ 69.694490] gfn_to_memslot+0x174/0x190
[ 69.694853] kvm_write_guest+0x50/0xb0
[ 69.695209] vgic_its_save_tables_v0+0x248/0x330
[ 69.695639] vgic_its_set_attr+0x298/0x3a0
[ 69.696024] kvm_device_ioctl_attr+0x9c/0xd8
[ 69.696424] kvm_device_ioctl+0x8c/0xf8
[ 69.696788] do_vfs_ioctl+0xc8/0x960
[ 69.697128] ksys_ioctl+0x8c/0xa0
[ 69.697445] __arm64_sys_ioctl+0x28/0x38
[ 69.697817] el0_svc_common+0xd8/0x138
[ 69.698173] el0_svc_handler+0x38/0x78
[ 69.698528] el0_svc+0x8/0xc
The fix is to obviously take the srcu lock, just like we do on the
read side of things since bf308242ab. One wonders why this wasn't
fixed at the same time, but hey...
Fixes: bf308242ab ("KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
We've become very cautious to now always reset the vcpu when nothing
is loaded on the physical CPU. To do so, we now disable preemption
and do a kvm_arch_vcpu_put() to make sure we have all the state
in memory (and that it won't be loaded behind out back).
This now causes issues with resetting the PMU, which calls into perf.
Perf itself uses mutexes, which clashes with the lack of preemption.
It is worth realizing that the PMU is fully emulated, and that
no PMU state is ever loaded on the physical CPU. This means we can
perfectly reset the PMU outside of the non-preemptible section.
Fixes: e761a927bc ("KVM: arm/arm64: Reset the VCPU without preemption and vcpu state loaded")
Reported-by: Julien Grall <julien.grall@arm.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
- An interrupt masking fix for Loongson-based Lemote 2F systems (fixing
a regression from v3.19).
- A relocation fix for configurations in which the devicetree is stored
in an ELF section (fixing a regression from v4.7).
- Fix jump labels for MIPSr6 kernels where they previously could
inadvertently place a control transfer instruction in a forbidden slot
& take unexpected exceptions (fixing MIPSr6 support added in v4.0).
- Extend an existing USB power workaround for the Netgear WNDR3400 to v2
boards in addition to the v3 ones that already used it.
- Remove the custom MIPS32 definition of __kernel_fsid_t to make it
consistent with MIPS64 & every other architecture, in particular
resolving issues for code which tries to print the val field whose
type previously differed (though had identical memory layout).
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Merge tag 'mips_fixes_5.1_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS fixes from Paul Burton:
"A small batch of MIPS fixes for 5.1:
- An interrupt masking fix for Loongson-based Lemote 2F systems
(fixing a regression from v3.19)
- A relocation fix for configurations in which the devicetree is
stored in an ELF section (fixing a regression from v4.7)
- Fix jump labels for MIPSr6 kernels where they previously could
inadvertently place a control transfer instruction in a forbidden
slot & take unexpected exceptions (fixing MIPSr6 support added in
v4.0)
- Extend an existing USB power workaround for the Netgear WNDR3400 to
v2 boards in addition to the v3 ones that already used it
- Remove the custom MIPS32 definition of __kernel_fsid_t to make it
consistent with MIPS64 & every other architecture, in particular
resolving issues for code which tries to print the val field whose
type previously differed (though had identical memory layout)"
* tag 'mips_fixes_5.1_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: Remove custom MIPS32 __kernel_fsid_t type
mips: bcm47xx: Enable USB power on Netgear WNDR3400v2
MIPS: Fix kernel crash for R6 in jump label branch function
MIPS: Ensure ELF appended dtb is relocated
mips: loongson64: lemote-2f: Add IRQF_NO_SUSPEND to "cascade" irqaction.
HiSilicon Taishan v110 CPUs didn't implement CSV3 field of the
ID_AA64PFR0_EL1 and are not susceptible to Meltdown, so whitelist
the MIDR in kpti_safe_list[] table.
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Zhangshaokun <zhangshaokun@hisilicon.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Adding the MIDR encodings for HiSilicon Taishan v110 CPUs,
which is used in Kunpeng ARM64 server SoCs. TSV110 is the
abbreviation of Taishan v110.
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Zhangshaokun <zhangshaokun@hisilicon.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The ARM64 implements the save_stack_trace_regs function, but it is
unusable for any diagnostic tooling compiled as a kernel module due
the missing EXPORT_SYMBOL_GPL for the function. Export
save_stack_trace_regs() to align with other architectures such as
s390, openrisc, and powerpc. This is similar to the ARM64 export of
save_stack_trace_tsk() added in git commit e27c7fa015.
Signed-off-by: William Cohen <wcohen@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Fujitsu erratum 010001 applies to A64FX v0r0 and v1r0, and we try to
handle either by masking MIDR with MIDR_FUJITSU_ERRATUM_010001_MASK
before comparing it to MIDR_FUJITSU_ERRATUM_010001.
Unfortunately, MIDR_FUJITSU_ERRATUM_010001 is constructed incorrectly
using MIDR_VARIANT(), which is intended to extract the variant field
from MIDR_EL1, rather than generate the field in-place. This results in
MIDR_FUJITSU_ERRATUM_010001 being all-ones, and we only match A64FX
v0r0.
This patch uses MIDR_CPU_VAR_REV() to generate an in-place mask for the
variant field, ensuring the we match both v0r0 and v1r0.
Fixes: 3e32131abc ("arm64: Add workaround for Fujitsu A64FX erratum 010001")
Reported-by: "Okamoto, Takayuki" <tokamoto@jp.fujitsu.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[catalin.marinas@arm.com: fixed the patch author]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Use arch_populate_kprobe_blacklist() instead of
arch_within_kprobe_blacklist() so that we can see the full
blacklisted symbols under the debugfs.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: Add arch_populate_kprobe_blacklist() comment]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Move exception/irqentry text address check in blacklist,
since those are symbol based rejection.
If we prohibit probing on the symbols in exception_text,
those should be blacklisted.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Remove unneeded RODATA check from arch_prepare_kprobe().
Since check_kprobe_address_safe() already ensured that
the probe address is in kernel text, we don't need to
check whether the address in RODATA or not. That must
be always false.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Move extable address check into arch_prepare_kprobe() from
arch_within_kprobe_blacklist().
The blacklist is exposed via debugfs as a list of symbols.
The extable entries are smaller, so must be filtered out
by arch_prepare_kprobe().
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
