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Linux kernel
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Streamline the PID.PIR check and change its call sites to use
the newly added helper.
Suggested-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When vCPU enters block phase, pi_pre_block() inserts vCPU to a per pCPU
linked list of all vCPUs that are blocked on this pCPU. Afterwards, it
changes PID.NV to POSTED_INTR_WAKEUP_VECTOR which its handler
(wakeup_handler()) is responsible to kick (unblock) any vCPU on that
linked list that now has pending posted interrupts.
While vCPU is blocked (in kvm_vcpu_block()), it may be preempted which
will cause vmx_vcpu_pi_put() to set PID.SN. If later the vCPU will be
scheduled to run on a different pCPU, vmx_vcpu_pi_load() will clear
PID.SN but will also *overwrite PID.NDST to this different pCPU*.
Instead of keeping it with original pCPU which vCPU had entered block
phase on.
This results in an issue because when a posted interrupt is delivered, as
the wakeup_handler() will be executed and fail to find blocked vCPU on
its per pCPU linked list of all vCPUs that are blocked on this pCPU.
Which is due to the vCPU being placed on a *different* per pCPU
linked list i.e. the original pCPU in which it entered block phase.
The regression is introduced by commit c112b5f50232 ("KVM: x86:
Recompute PID.ON when clearing PID.SN"). Therefore, partially revert
it and reintroduce the condition in vmx_vcpu_pi_load() responsible for
avoiding changing PID.NDST when loading a blocked vCPU.
Fixes: c112b5f50232 ("KVM: x86: Recompute PID.ON when clearing PID.SN")
Tested-by: Nathan Ni <nathan.ni@oracle.com>
Co-developed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 17e433b54393 ("KVM: Fix leak vCPU's VMCS value into other pCPU")
introduced vmx_dy_apicv_has_pending_interrupt() in order to determine
if a vCPU have a pending posted interrupt. This routine is used by
kvm_vcpu_on_spin() when searching for a a new runnable vCPU to schedule
on pCPU instead of a vCPU doing busy loop.
vmx_dy_apicv_has_pending_interrupt() determines if a
vCPU has a pending posted interrupt solely based on PID.ON. However,
when a vCPU is preempted, vmx_vcpu_pi_put() sets PID.SN which cause
raised posted interrupts to only set bit in PID.PIR without setting
PID.ON (and without sending notification vector), as depicted in VT-d
manual section 5.2.3 "Interrupt-Posting Hardware Operation".
Therefore, checking PID.ON is insufficient to determine if a vCPU has
pending posted interrupts and instead we should also check if there is
some bit set on PID.PIR if PID.SN=1.
Fixes: 17e433b54393 ("KVM: Fix leak vCPU's VMCS value into other pCPU")
Reviewed-by: Jagannathan Raman <jag.raman@oracle.com>
Co-developed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The Outstanding Notification (ON) bit is part of the Posted Interrupt
Descriptor (PID) as opposed to the Posted Interrupts Register (PIR).
The latter is a bitmap for pending vectors.
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The three MSR lists(msrs_to_save[], emulated_msrs[] and
msr_based_features[]) are global arrays of kvm.ko, which are
adjusted (copy supported MSRs forward to override the unsupported MSRs)
when insmod kvm-{intel,amd}.ko, but it doesn't reset these three arrays
to their initial value when rmmod kvm-{intel,amd}.ko. Thus, at the next
installation, kvm-{intel,amd}.ko will do operations on the modified
arrays with some MSRs lost and some MSRs duplicated.
So define three constant arrays to hold the initial MSR lists and
initialize msrs_to_save[], emulated_msrs[] and msr_based_features[]
based on the constant arrays.
Cc: stable@vger.kernel.org
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
[Remove now useless conditionals. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reported by syzkaller:
=============================
WARNING: suspicious RCU usage
-----------------------------
./include/linux/kvm_host.h:536 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
no locks held by repro_11/12688.
stack backtrace:
Call Trace:
dump_stack+0x7d/0xc5
lockdep_rcu_suspicious+0x123/0x170
kvm_dev_ioctl+0x9a9/0x1260 [kvm]
do_vfs_ioctl+0x1a1/0xfb0
ksys_ioctl+0x6d/0x80
__x64_sys_ioctl+0x73/0xb0
do_syscall_64+0x108/0xaa0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Commit a97b0e773e4 (kvm: call kvm_arch_destroy_vm if vm creation fails)
sets users_count to 1 before kvm_arch_init_vm(), however, if kvm_arch_init_vm()
fails, we need to decrease this count. By moving it earlier, we can push
the decrease to out_err_no_arch_destroy_vm without introducing yet another
error label.
syzkaller source: https://syzkaller.appspot.com/x/repro.c?x=15209b84e00000
Reported-by: syzbot+75475908cd0910f141ee@syzkaller.appspotmail.com
Fixes: a97b0e773e49 ("kvm: call kvm_arch_destroy_vm if vm creation fails")
Cc: Jim Mattson <jmattson@google.com>
Analyzed-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reported by syzkaller:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 14727 Comm: syz-executor.3 Not tainted 5.4.0-rc4+ #0
RIP: 0010:kvm_coalesced_mmio_init+0x5d/0x110 arch/x86/kvm/../../../virt/kvm/coalesced_mmio.c:121
Call Trace:
kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3446 [inline]
kvm_dev_ioctl+0x781/0x1490 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3494
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0x196/0x1150 fs/ioctl.c:696
ksys_ioctl+0x62/0x90 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:718
do_syscall_64+0xca/0x5d0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Commit 9121923c457d ("kvm: Allocate memslots and buses before calling kvm_arch_init_vm")
moves memslots and buses allocations around, however, if kvm->srcu/irq_srcu fails
initialization, NULL will be returned instead of error code, NULL will not be intercepted
in kvm_dev_ioctl_create_vm() and be dereferenced by kvm_coalesced_mmio_init(), this patch
fixes it.
Moving the initialization is required anyway to avoid an incorrect synchronize_srcu that
was also reported by syzkaller:
wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136
__synchronize_srcu+0x197/0x250 kernel/rcu/srcutree.c:921
synchronize_srcu_expedited kernel/rcu/srcutree.c:946 [inline]
synchronize_srcu+0x239/0x3e8 kernel/rcu/srcutree.c:997
kvm_page_track_unregister_notifier+0xe7/0x130 arch/x86/kvm/page_track.c:212
kvm_mmu_uninit_vm+0x1e/0x30 arch/x86/kvm/mmu.c:5828
kvm_arch_destroy_vm+0x4a2/0x5f0 arch/x86/kvm/x86.c:9579
kvm_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:702 [inline]
so do it.
Reported-by: syzbot+89a8060879fa0bd2db4f@syzkaller.appspotmail.com
Reported-by: syzbot+e27e7027eb2b80e44225@syzkaller.appspotmail.com
Fixes: 9121923c457d ("kvm: Allocate memslots and buses before calling kvm_arch_init_vm")
Cc: Jim Mattson <jmattson@google.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull ARM SoC fixes from Olof Johansson:
"A set of fixes that have trickled in over the last couple of weeks:
- MAINTAINER update for Cavium/Marvell ThunderX2
- stm32 tweaks to pinmux for Joystick/Camera, and RAM allocation for
CAN interfaces
- i.MX fixes for voltage regulator GPIO mappings, fixes voltage
scaling issues
- More i.MX fixes for various issues on i.MX eval boards: interrupt
storm due to u-boot leaving pins in new states, fixing power button
config, a couple of compatible-string corrections.
- Powerdown and Suspend/Resume fixes for Allwinner A83-based tablets
- A few documentation tweaks and a fix of a memory leak in the reset
subsystem"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
MAINTAINERS: update Cavium ThunderX2 maintainers
ARM: dts: stm32: change joystick pinctrl definition on stm32mp157c-ev1
ARM: dts: stm32: remove OV5640 pinctrl definition on stm32mp157c-ev1
ARM: dts: stm32: Fix CAN RAM mapping on stm32mp157c
ARM: dts: stm32: relax qspi pins slew-rate for stm32mp157
arm64: dts: zii-ultra: fix ARM regulator GPIO handle
ARM: sunxi: Fix CPU powerdown on A83T
ARM: dts: sun8i-a83t-tbs-a711: Fix WiFi resume from suspend
arm64: dts: imx8mn: fix compatible string for sdma
arm64: dts: imx8mm: fix compatible string for sdma
reset: fix reset_control_ops kerneldoc comment
ARM: dts: imx6-logicpd: Re-enable SNVS power key
soc: imx: gpc: fix initialiser format
ARM: dts: imx6qdl-sabreauto: Fix storm of accelerometer interrupts
arm64: dts: ls1028a: fix a compatible issue
reset: fix reset_control_get_exclusive kerneldoc comment
reset: fix reset_control_lookup kerneldoc comment
reset: fix of_reset_control_get_count kerneldoc comment
reset: fix of_reset_simple_xlate kerneldoc comment
reset: Fix memory leak in reset_control_array_put()
Pull IIO fixes and staging driver from Greg KH:
"Here is a mix of a number of IIO driver fixes for 5.4-rc7, and a whole
new staging driver.
The IIO fixes resolve some reported issues, all are tiny.
The staging driver addition is the vboxsf filesystem, which is the
VirtualBox guest shared folder code. Hans has been trying to get
filesystem reviewers to review the code for many months now, and
Christoph finally said to just merge it in staging now as it is
stand-alone and the filesystem people can review it easier over time
that way.
I know it's late for this big of an addition, but it is stand-alone.
The code has been in linux-next for a while, long enough to pick up a
few tiny fixes for it already so people are looking at it.
All of these have been in linux-next with no reported issues"
* tag 'staging-5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: Fix error return code in vboxsf_fill_super()
staging: vboxsf: fix dereference of pointer dentry before it is null checked
staging: vboxsf: Remove unused including <linux/version.h>
staging: Add VirtualBox guest shared folder (vboxsf) support
iio: adc: stm32-adc: fix stopping dma
iio: imu: inv_mpu6050: fix no data on MPU6050
iio: srf04: fix wrong limitation in distance measuring
iio: imu: adis16480: make sure provided frequency is positive
jnair is no longer at caviumnetworks.com (or at marvell.com). This also
means that Cavium ThunderX2 will now be maintained by Robert.
This is probably a good time to map various email addresses used for
my patches to my personal email ID, update .mailmap to do this.
Link: https://lore.kernel.org/r/20191106035203.5389-1-c.jayachandran@gmail.com
Signed-off-by: Jayachandran C <c.jayachandran@gmail.com>
Acked-by: Robert Richter <rrichter@marvell.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Pull char/misc driver fixes from Greg KH:
"Here are a number of late-arrival driver fixes for issues reported for
some char/misc drivers for 5.4-rc7
These all come from the different subsystem/driver maintainers as
things that they had reports for and wanted to see fixed.
All of these have been in linux-next with no reported issues"
* tag 'char-misc-5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
intel_th: pci: Add Jasper Lake PCH support
intel_th: pci: Add Comet Lake PCH support
intel_th: msu: Fix possible memory leak in mode_store()
intel_th: msu: Fix overflow in shift of an unsigned int
intel_th: msu: Fix missing allocation failure check on a kstrndup
intel_th: msu: Fix an uninitialized mutex
intel_th: gth: Fix the window switching sequence
soundwire: slave: fix scanf format
soundwire: intel: fix intel_register_dai PDI offsets and numbers
interconnect: Add locking in icc_set_tag()
interconnect: qcom: Fix icc_onecell_data allocation
soundwire: depend on ACPI || OF
soundwire: depend on ACPI
thunderbolt: Drop unnecessary read when writing LC command in Ice Lake
thunderbolt: Fix lockdep circular locking depedency warning
thunderbolt: Read DP IN adapter first two dwords in one go
Fix to return negative error code -ENOMEM from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: df4028658f9d ("staging: Add VirtualBox guest shared folder (vboxsf) support")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20191106115954.114678-1-weiyongjun1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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