Set the min_level for the TDP iterator at the root level when zapping all
SPTEs to optimize the iterator's try_step_down(). Zapping a non-leaf
SPTE will recursively zap all its children, thus there is no need for the
iterator to attempt to step down. This avoids rereading the top-level
SPTEs after they are zapped by causing try_step_down() to short-circuit.
In most cases, optimizing try_step_down() will be in the noise as the cost
of zapping SPTEs completely dominates the overall time. The optimization
is however helpful if the zap occurs with relatively few SPTEs, e.g. if KVM
is zapping in response to multiple memslot updates when userspace is adding
and removing read-only memslots for option ROMs. In that case, the task
doing the zapping likely isn't a vCPU thread, but it still holds mmu_lock
for read and thus can be a noisy neighbor of sorts.
Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210812181414.3376143-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pass "all ones" as the end GFN to signal "zap all" for the TDP MMU and
really zap all SPTEs in this case. As is, zap_gfn_range() skips non-leaf
SPTEs whose range exceeds the range to be zapped. If shadow_phys_bits is
not aligned to the range size of top-level SPTEs, e.g. 512gb with 4-level
paging, the "zap all" flows will skip top-level SPTEs whose range extends
beyond shadow_phys_bits and leak their SPs when the VM is destroyed.
Use the current upper bound (based on host.MAXPHYADDR) to detect that the
caller wants to zap all SPTEs, e.g. instead of using the max theoretical
gfn, 1 << (52 - 12). The more precise upper bound allows the TDP iterator
to terminate its walk earlier when running on hosts with MAXPHYADDR < 52.
Add a WARN on kmv->arch.tdp_mmu_pages when the TDP MMU is destroyed to
help future debuggers should KVM decide to leak SPTEs again.
The bug is most easily reproduced by running (and unloading!) KVM in a
VM whose host.MAXPHYADDR < 39, as the SPTE for gfn=0 will be skipped.
=============================================================================
BUG kvm_mmu_page_header (Not tainted): Objects remaining in kvm_mmu_page_header on __kmem_cache_shutdown()
-----------------------------------------------------------------------------
Slab 0x000000004d8f7af1 objects=22 used=2 fp=0x00000000624d29ac flags=0x4000000000000200(slab|zone=1)
CPU: 0 PID: 1582 Comm: rmmod Not tainted 5.14.0-rc2+ #420
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
dump_stack_lvl+0x45/0x59
slab_err+0x95/0xc9
__kmem_cache_shutdown.cold+0x3c/0x158
kmem_cache_destroy+0x3d/0xf0
kvm_mmu_module_exit+0xa/0x30 [kvm]
kvm_arch_exit+0x5d/0x90 [kvm]
kvm_exit+0x78/0x90 [kvm]
vmx_exit+0x1a/0x50 [kvm_intel]
__x64_sys_delete_module+0x13f/0x220
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
Fixes: faaf05b00a ("kvm: x86/mmu: Support zapping SPTEs in the TDP MMU")
Cc: stable@vger.kernel.org
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210812181414.3376143-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Take a signed 'long' instead of an 'unsigned long' for the number of
pages to add/subtract to the total number of pages used by the MMU. This
fixes a zero-extension bug on 32-bit kernels that effectively corrupts
the per-cpu counter used by the shrinker.
Per-cpu counters take a signed 64-bit value on both 32-bit and 64-bit
kernels, whereas kvm_mod_used_mmu_pages() takes an unsigned long and thus
an unsigned 32-bit value on 32-bit kernels. As a result, the value used
to adjust the per-cpu counter is zero-extended (unsigned -> signed), not
sign-extended (signed -> signed), and so KVM's intended -1 gets morphed to
4294967295 and effectively corrupts the counter.
This was found by a staggering amount of sheer dumb luck when running
kvm-unit-tests on a 32-bit KVM build. The shrinker just happened to kick
in while running tests and do_shrink_slab() logged an error about trying
to free a negative number of objects. The truly lucky part is that the
kernel just happened to be a slightly stale build, as the shrinker no
longer yells about negative objects as of commit 18bb473e50 ("mm:
vmscan: shrink deferred objects proportional to priority").
vmscan: shrink_slab: mmu_shrink_scan+0x0/0x210 [kvm] negative objects to delete nr=-858993460
Fixes: bc8a3d8925 ("kvm: mmu: Fix overflow on kvm mmu page limit calculation")
Cc: stable@vger.kernel.org
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210804214609.1096003-1-seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM SEV code uses bitmaps to manage ASID states. ASID 0 was always skipped
because it is never used by VM. Thus, in existing code, ASID value and its
bitmap postion always has an 'offset-by-1' relationship.
Both SEV and SEV-ES shares the ASID space, thus KVM uses a dynamic range
[min_asid, max_asid] to handle SEV and SEV-ES ASIDs separately.
Existing code mixes the usage of ASID value and its bitmap position by
using the same variable called 'min_asid'.
Fix the min_asid usage: ensure that its usage is consistent with its name;
allocate extra size for ASID 0 to ensure that each ASID has the same value
with its bitmap position. Add comments on ASID bitmap allocation to clarify
the size change.
Signed-off-by: Mingwei Zhang <mizhang@google.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Marc Orr <marcorr@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Alper Gun <alpergun@google.com>
Cc: Dionna Glaze <dionnaglaze@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vipin Sharma <vipinsh@google.com>
Cc: Peter Gonda <pgonda@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Message-Id: <20210802180903.159381-1-mizhang@google.com>
[Fix up sev_asid_free to also index by ASID, as suggested by Sean
Christopherson, and use nr_asids in sev_cpu_init. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use the raw ASID, not ASID-1, when nullifying the last used VMCB when
freeing an SEV ASID. The consumer, pre_sev_run(), indexes the array by
the raw ASID, thus KVM could get a false negative when checking for a
different VMCB if KVM manages to reallocate the same ASID+VMCB combo for
a new VM.
Note, this cannot cause a functional issue _in the current code_, as
pre_sev_run() also checks which pCPU last did VMRUN for the vCPU, and
last_vmentry_cpu is initialized to -1 during vCPU creation, i.e. is
guaranteed to mismatch on the first VMRUN. However, prior to commit
8a14fe4f0c ("kvm: x86: Move last_cpu into kvm_vcpu_arch as
last_vmentry_cpu"), SVM tracked pCPU on its own and zero-initialized the
last_cpu variable. Thus it's theoretically possible that older versions
of KVM could miss a TLB flush if the first VMRUN is on pCPU0 and the ASID
and VMCB exactly match those of a prior VM.
Fixes: 70cd94e60c ("KVM: SVM: VMRUN should use associated ASID when SEV is enabled")
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
TLFS states that "Availability of the XMM fast hypercall interface is
indicated via the “Hypervisor Feature Identification” CPUID Leaf
(0x40000003, see section 2.4.4) ... Any attempt to use this interface
when the hypervisor does not indicate availability will result in a #UD
fault."
Implement the check for 'strict' mode (KVM_CAP_HYPERV_ENFORCE_CPUID).
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Siddharth Chandrasekaran <sidcha@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210730122625.112848-4-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Once an exception has been injected, any side effects related to
the exception (such as setting CR2 or DR6) have been taked place.
Therefore, once KVM sets the VM-entry interruption information
field or the AMD EVENTINJ field, the next VM-entry must deliver that
exception.
Pending interrupts are processed after injected exceptions, so
in theory it would not be a problem to use KVM_INTERRUPT when
an injected exception is present. However, DOSEMU is using
run->ready_for_interrupt_injection to detect interrupt windows
and then using KVM_SET_SREGS/KVM_SET_REGS to inject the
interrupt manually. For this to work, the interrupt window
must be delayed after the completion of the previous event
injection.
Cc: stable@vger.kernel.org
Reported-by: Stas Sergeev <stsp2@yandex.ru>
Tested-by: Stas Sergeev <stsp2@yandex.ru>
Fixes: 71cc849b70 ("KVM: x86: Fix split-irqchip vs interrupt injection window request")
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently when SVM is enabled in guest CPUID, AVIC is inhibited as soon
as the guest CPUID is set.
AVIC happens to be fully disabled on all vCPUs by the time any guest
entry starts (if after migration the entry can be nested).
The reason is that currently we disable avic right away on vCPU from which
the kvm_request_apicv_update was called and for this case, it happens to be
called on all vCPUs (by svm_vcpu_after_set_cpuid).
After we stop doing this, AVIC will end up being disabled only when
KVM_REQ_APICV_UPDATE is processed which is after we done switching to the
nested guest.
Fix this by just using vmcb01 in svm_refresh_apicv_exec_ctrl for avic
(which is a right thing to do anyway).
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210713142023.106183-4-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It is possible for AVIC inhibit and AVIC active state to be mismatched.
Currently we disable AVIC right away on vCPU which started the AVIC inhibit
request thus this warning doesn't trigger but at least in theory,
if svm_set_vintr is called at the same time on multiple vCPUs,
the warning can happen.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210713142023.106183-2-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
commit bc9e9e672d ("KVM: debugfs: Reuse binary stats descriptors")
did replace the old definitions with the binary ones. While doing that
it missed that some files are names different than the counters. This
is especially important for kvm_stat which does have special handling
for counters named instruction_*.
Fixes: commit bc9e9e672d ("KVM: debugfs: Reuse binary stats descriptors")
CC: Jing Zhang <jingzhangos@google.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20210726150108.5603-1-borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now, svm_hv_vmcb_dirty_nested_enlightenments has an incorrect
dereference of vmcb->control.reserved_sw before the vmcb is checked
for being non-NULL. The compiler is usually sinking the dereference
after the check; instead of doing this ourselves in the source,
ensure that svm_hv_vmcb_dirty_nested_enlightenments is only called
with a non-NULL VMCB.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Vineeth Pillai <viremana@linux.microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[Untested for now due to issues with my AMD machine. - Paolo]
KVM_MAX_VCPU_ID is the maximum vcpu-id of a guest, and not the number
of vcpu-ids. Fix array indexed by vcpu-id to have KVM_MAX_VCPU_ID+1
elements.
Note that this is currently no real problem, as KVM_MAX_VCPU_ID is
an odd number, resulting in always enough padding being available at
the end of those arrays.
Nevertheless this should be fixed in order to avoid rare problems in
case someone is using an even number for KVM_MAX_VCPU_ID.
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-Id: <20210701154105.23215-2-jgross@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
MSR_KVM_ASYNC_PF_ACK MSR is part of interrupt based asynchronous page fault
interface and not the original (deprecated) KVM_FEATURE_ASYNC_PF. This is
stated in Documentation/virt/kvm/msr.rst.
Fixes: 66570e966d ("kvm: x86: only provide PV features if enabled in guest's CPUID")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Message-Id: <20210722123018.260035-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
To match svm_copy_vmrun_state(), rename nested_svm_vmloadsave() to
svm_copy_vmloadsave_state().
Opportunistically add missing braces to 'else' branch in
vmload_vmsave_interception().
No functional change intended.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210716144104.465269-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM/arm64 fixes for 5.14, take #1
- Fix MTE shared page detection
- Fix selftest use of obsolete pthread_yield() in favour of sched_yield()
- Enable selftest's use of PMU registers when asked to
Pull ARM SoC fixes from Arnd Bergmann:
"Here are the patches for this week that came as the fallout of the
merge window:
- Two fixes for the NVidia memory controller driver
- multiple defconfig files get patched to turn CONFIG_FB back on
after that is no longer selected by CONFIG_DRM
- ffa and scmpi firmware drivers fixes, mostly addressing compiler
and documentation warnings
- Platform specific fixes for device tree files on ASpeed, Renesas
and NVidia SoC, mostly for recent regressions.
- A workaround for a regression on the USB PHY with devlink when the
usb-nop-xceiv driver is not available until the rootfs is mounted.
- Device tree compiler warnings in Arm Versatile-AB"
* tag 'soc-fixes-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (35 commits)
ARM: dts: versatile: Fix up interrupt controller node names
ARM: multi_v7_defconfig: Make NOP_USB_XCEIV driver built-in
ARM: configs: Update u8500_defconfig
ARM: configs: Update Vexpress defconfig
ARM: configs: Update Versatile defconfig
ARM: configs: Update RealView defconfig
ARM: configs: Update Integrator defconfig
arm: Typo s/PCI_IXP4XX_LEGACY/IXP4XX_PCI_LEGACY/
firmware: arm_scmi: Fix range check for the maximum number of pending messages
firmware: arm_scmi: Avoid padding in sensor message structure
firmware: arm_scmi: Fix kernel doc warnings about return values
firmware: arm_scpi: Fix kernel doc warnings
firmware: arm_scmi: Fix kernel doc warnings
ARM: shmobile: defconfig: Restore graphical consoles
firmware: arm_ffa: Fix a possible ffa_linux_errmap buffer overflow
firmware: arm_ffa: Fix the comment style
firmware: arm_ffa: Simplify probe function
firmware: arm_ffa: Ensure drivers provide a probe function
firmware: arm_scmi: Fix possible scmi_linux_errmap buffer overflow
firmware: arm_scmi: Ensure drivers provide a probe function
...
Pull arm64 fixes from Will Deacon:
"The bulk of the diffstat consists of changes to our uaccess routines
so that they fall back to bytewise copying prior to reporting complete
failure when the initial (multi-byte) access faults.
However, the most disappointing change here is that we've had to bump
ARCH_DMA_MINALIGN back to 128 bytes thanks to Qualcomm's "Kryo" CPU,
which ended up in the MSM8996 mobile SoC. Still, at least we're now
aware of this design and one of the hardware designers confirmed the
L2 cacheline size for us.
Summary:
- Fix instrumentation annotations for entry code
- Ensure kernel MTE state is restored correctly on resume from suspend
- Fix MTE fault from new strlen() routine
- Fallback to byte-wise accesses on initial uaccess fault
- Bump Clang requirement for BTI
- Revert ARCH_DMA_MINALIGN back to 128 bytes (shakes fist at Qualcomm)"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: entry: fix KCOV suppression
arm64: entry: add missing noinstr
arm64: mte: fix restoration of GCR_EL1 from suspend
arm64: Avoid premature usercopy failure
arm64: Restrict ARM64_BTI_KERNEL to clang 12.0.0 and newer
Revert "arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)"
arm64: Add missing header <asm/smp.h> in two files
arm64: fix strlen() with CONFIG_KASAN_HW_TAGS
Once the new schema interrupt-controller/arm,vic.yaml is added, we get
the below warnings:
arch/arm/boot/dts/versatile-ab.dt.yaml:
intc@10140000: $nodename:0: 'intc@10140000' does not match
'^interrupt-controller(@[0-9a-f,]+)*$'
arch/arm/boot/dts/versatile-ab.dt.yaml:
intc@10140000: 'clear-mask' does not match any of the regexes
Fix the node names for the interrupt controller to conform
to the standard node name interrupt-controller@.. Also drop invalid
clear-mask property.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210701132118.759454-1-sudeep.holla@arm.com'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The usage of usb-nop-xceiv PHY on Raspberry Pi boards with BCM283x has
been a "regression source" a lot of times. The last case is breakage of
USB mass storage boot has been commit e590474768 ("driver core: Set
fw_devlink=on by default") for multi_v7_defconfig. As long as
NOP_USB_XCEIV is configured as module, the dwc2 USB driver defer probing
endlessly and prevent booting from USB mass storage device. So make
the driver built-in as in bcm2835_defconfig and arm64/defconfig.
Fixes: e590474768 ("driver core: Set fw_devlink=on by default")
Reported-by: Ojaswin Mujoo <ojaswin98@gmail.com>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/1625915095-23077-1-git-send-email-stefan.wahren@i2se.com'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This updates the Versatile Express defconfig for the changes
in the v5.14-rc1 kernel:
- The Framebuffer CONFIG_FB needs to be explicitly selected
or we don't get any framebuffer anymore. DRM has stopped to
select FB because of circular dependency.
- CONFIG_CMA options were moved around.
- CONFIG_MODULES options were moved around.
- CONFIG_CRYPTO_HW was moved around.
Fixes: f611b1e762 ("drm: Avoid circular dependencies for CONFIG_FB")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20210713133708.94397-1-linus.walleij@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This updates the Versatile defconfig for the changes
in the v5.14-rc1 kernel:
- The Framebuffer CONFIG_FB needs to be explicitly selected
or we don't get any framebuffer anymore. DRM has stopped to
select FB because of circular dependency.
- The CONFIG_FB_MODE_HELPERS are not needed when using DRM
framebuffer emulation as DRM does.
- The Acorn fonts are removed, the default framebuffer font
works fine. I don't know why this was selected in the first
place or how the Kconfig was altered so it was removed.
Fixes: f611b1e762 ("drm: Avoid circular dependencies for CONFIG_FB")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210714081819.139210-1-linus.walleij@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This updates the RealView defconfig for the changes
in the v5.14-rc1 kernel:
- The Framebuffer CONFIG_FB needs to be explicitly selected
or we don't get any framebuffer anymore. DRM has stopped to
select FB because of circular dependency.
- The CONFIG_FB_MODE_HELPERS are not needed when using DRM
framebuffer emulation as DRM does.
- Drop two unused penguin logos.
Fixes: f611b1e762 ("drm: Avoid circular dependencies for CONFIG_FB")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210714090040.182381-1-linus.walleij@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This updates the Integrator defconfig for the changes
in the v5.14-rc1 kernel:
- The Framebuffer CONFIG_FB needs to be explicitly selected
or we don't get any framebuffer anymore. DRM has stopped to
select FB because of circular dependency.
- Drop the unused Matrox FB drivers that are only used with
specific PCI cards.
Fixes: f611b1e762 ("drm: Avoid circular dependencies for CONFIG_FB")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210714122703.212609-1-linus.walleij@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
arm64: tegra: Device tree fixes for v5.14-rc1
This contains two late fixes for Tegra194 device tree files to restore
USB and audio functionality after enabling system-wide IOMMU support.
* tag 'tegra-for-5.14-arm64-dt-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
arm64: tegra: Enable SMMU support for USB on Tegra194
arm64: tegra: Enable audio IOMMU support on Tegra194
Link: https://lore.kernel.org/r/20210709150220.2543875-1-thierry.reding@gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull fallthrough fixes from Gustavo Silva:
"This fixes many fall-through warnings when building with Clang and
-Wimplicit-fallthrough, and also enables -Wimplicit-fallthrough for
Clang, globally.
It's also important to notice that since we have adopted the use of
the pseudo-keyword macro fallthrough, we also want to avoid having
more /* fall through */ comments being introduced. Contrary to GCC,
Clang doesn't recognize any comments as implicit fall-through markings
when the -Wimplicit-fallthrough option is enabled.
So, in order to avoid having more comments being introduced, we use
the option -Wimplicit-fallthrough=5 for GCC, which similar to Clang,
will cause a warning in case a code comment is intended to be used as
a fall-through marking. The patch for Makefile also enforces this.
We had almost 4,000 of these issues for Clang in the beginning, and
there might be a couple more out there when building some
architectures with certain configurations. However, with the recent
fixes I think we are in good shape and it is now possible to enable
the warning for Clang"
* tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits)
Makefile: Enable -Wimplicit-fallthrough for Clang
powerpc/smp: Fix fall-through warning for Clang
dmaengine: mpc512x: Fix fall-through warning for Clang
usb: gadget: fsl_qe_udc: Fix fall-through warning for Clang
powerpc/powernv: Fix fall-through warning for Clang
MIPS: Fix unreachable code issue
MIPS: Fix fall-through warnings for Clang
ASoC: Mediatek: MT8183: Fix fall-through warning for Clang
power: supply: Fix fall-through warnings for Clang
dmaengine: ti: k3-udma: Fix fall-through warning for Clang
s390: Fix fall-through warnings for Clang
dmaengine: ipu: Fix fall-through warning for Clang
iommu/arm-smmu-v3: Fix fall-through warning for Clang
mmc: jz4740: Fix fall-through warning for Clang
PCI: Fix fall-through warning for Clang
scsi: libsas: Fix fall-through warning for Clang
video: fbdev: Fix fall-through warning for Clang
math-emu: Fix fall-through warning
cpufreq: Fix fall-through warning for Clang
drm/msm: Fix fall-through warning in msm_gem_new_impl()
...
Pull kvm fixes from Paolo Bonzini:
- Allow again loading KVM on 32-bit non-PAE builds
- Fixes for host SMIs on AMD
- Fixes for guest SMIs on AMD
- Fixes for selftests on s390 and ARM
- Fix memory leak
- Enforce no-instrumentation area on vmentry when hardware breakpoints
are in use.
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits)
KVM: selftests: smm_test: Test SMM enter from L2
KVM: nSVM: Restore nested control upon leaving SMM
KVM: nSVM: Fix L1 state corruption upon return from SMM
KVM: nSVM: Introduce svm_copy_vmrun_state()
KVM: nSVM: Check that VM_HSAVE_PA MSR was set before VMRUN
KVM: nSVM: Check the value written to MSR_VM_HSAVE_PA
KVM: SVM: Fix sev_pin_memory() error checks in SEV migration utilities
KVM: SVM: Return -EFAULT if copy_to_user() for SEV mig packet header fails
KVM: SVM: add module param to control the #SMI interception
KVM: SVM: remove INIT intercept handler
KVM: SVM: #SMI interception must not skip the instruction
KVM: VMX: Remove vmx_msr_index from vmx.h
KVM: X86: Disable hardware breakpoints unconditionally before kvm_x86->run()
KVM: selftests: Address extra memslot parameters in vm_vaddr_alloc
kvm: debugfs: fix memory leak in kvm_create_vm_debugfs
KVM: x86/pmu: Clear anythread deprecated bit when 0xa leaf is unsupported on the SVM
KVM: mmio: Fix use-after-free Read in kvm_vm_ioctl_unregister_coalesced_mmio
KVM: SVM: Revert clearing of C-bit on GPA in #NPF handler
KVM: x86/mmu: Do not apply HPA (memory encryption) mask to GPAs
KVM: x86: Use kernel's x86_phys_bits to handle reduced MAXPHYADDR
...
We suppress KCOV for entry.o rather than entry-common.o. As entry.o is
built from entry.S, this is pointless, and permits instrumentation of
entry-common.o, which is built from entry-common.c.
Fix the Makefile to suppress KCOV for entry-common.o, as we had intended
to begin with. I've verified with objdump that this is working as
expected.
Fixes: bf6fa2c0dd ("arm64: entry: don't instrument entry code with KCOV")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210715123049.9990-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
We intend that all the early exception handling code is marked as
`noinstr`, but we forgot this for __el0_error_handler_common(), which is
called before we have completed entry from user mode. If it were
instrumented, we could run into problems with RCU, lockdep, etc.
Mark it as `noinstr` to prevent this.
The few other functions in entry-common.c which do not have `noinstr` are
called once we've completed entry, and are safe to instrument.
Fixes: bb8e93a287 ("arm64: entry: convert SError handlers to C")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210714172801.16475-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Since commit:
bad1e1c663 ("arm64: mte: switch GCR_EL1 in kernel entry and exit")
we saved/restored the user GCR_EL1 value at exception boundaries, and
update_gcr_el1_excl() is no longer used for this. However it is used to
restore the kernel's GCR_EL1 value when returning from a suspend state.
Thus, the comment is misleading (and an ISB is necessary).
When restoring the kernel's GCR value, we need an ISB to ensure this is
used by subsequent instructions. We don't necessarily get an ISB by
other means (e.g. if the kernel is built without support for pointer
authentication). As __cpu_setup() initialised GCR_EL1.Exclude to 0xffff,
until a context synchronization event, allocation tag 0 may be used
rather than the desired set of tags.
This patch drops the misleading comment, adds the missing ISB, and for
clarity folds update_gcr_el1_excl() into its only user.
Fixes: bad1e1c663 ("arm64: mte: switch GCR_EL1 in kernel entry and exit")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210714143843.56537-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Al reminds us that the usercopy API must only return complete failure
if absolutely nothing could be copied. Currently, if userspace does
something silly like giving us an unaligned pointer to Device memory,
or a size which overruns MTE tag bounds, we may fail to honour that
requirement when faulting on a multi-byte access even though a smaller
access could have succeeded.
Add a mitigation to the fixup routines to fall back to a single-byte
copy if we faulted on a larger access before anything has been written
to the destination, to guarantee making *some* forward progress. We
needn't be too concerned about the overall performance since this should
only occur when callers are doing something a bit dodgy in the first
place. Particularly broken userspace might still be able to trick
generic_perform_write() into an infinite loop by targeting write() at
an mmap() of some read-only device register where the fault-in load
succeeds but any store synchronously aborts such that copy_to_user() is
genuinely unable to make progress, but, well, don't do that...
CC: stable@vger.kernel.org
Reported-by: Chen Huang <chenhuang5@huawei.com>
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/dc03d5c675731a1f24a62417dba5429ad744234e.1626098433.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
If the VM was migrated while in SMM, no nested state was saved/restored,
and therefore svm_leave_smm has to load both save and control area
of the vmcb12. Save area is already loaded from HSAVE area,
so now load the control area as well from the vmcb12.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210628104425.391276-6-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VMCB split commit 4995a3685f ("KVM: SVM: Use a separate vmcb for the
nested L2 guest") broke return from SMM when we entered there from guest
(L2) mode. Gen2 WS2016/Hyper-V is known to do this on boot. The problem
manifests itself like this:
kvm_exit: reason EXIT_RSM rip 0x7ffbb280 info 0 0
kvm_emulate_insn: 0:7ffbb280: 0f aa
kvm_smm_transition: vcpu 0: leaving SMM, smbase 0x7ffb3000
kvm_nested_vmrun: rip: 0x000000007ffbb280 vmcb: 0x0000000008224000
nrip: 0xffffffffffbbe119 int_ctl: 0x01020000 event_inj: 0x00000000
npt: on
kvm_nested_intercepts: cr_read: 0000 cr_write: 0010 excp: 40060002
intercepts: fd44bfeb 0000217f 00000000
kvm_entry: vcpu 0, rip 0xffffffffffbbe119
kvm_exit: reason EXIT_NPF rip 0xffffffffffbbe119 info
200000006 1ab000
kvm_nested_vmexit: vcpu 0 reason npf rip 0xffffffffffbbe119 info1
0x0000000200000006 info2 0x00000000001ab000 intr_info 0x00000000
error_code 0x00000000
kvm_page_fault: address 1ab000 error_code 6
kvm_nested_vmexit_inject: reason EXIT_NPF info1 200000006 info2 1ab000
int_info 0 int_info_err 0
kvm_entry: vcpu 0, rip 0x7ffbb280
kvm_exit: reason EXIT_EXCP_GP rip 0x7ffbb280 info 0 0
kvm_emulate_insn: 0:7ffbb280: 0f aa
kvm_inj_exception: #GP (0x0)
Note: return to L2 succeeded but upon first exit to L1 its RIP points to
'RSM' instruction but we're not in SMM.
The problem appears to be that VMCB01 gets irreversibly destroyed during
SMM execution. Previously, we used to have 'hsave' VMCB where regular
(pre-SMM) L1's state was saved upon nested_svm_vmexit() but now we just
switch to VMCB01 from VMCB02.
Pre-split (working) flow looked like:
- SMM is triggered during L2's execution
- L2's state is pushed to SMRAM
- nested_svm_vmexit() restores L1's state from 'hsave'
- SMM -> RSM
- enter_svm_guest_mode() switches to L2 but keeps 'hsave' intact so we have
pre-SMM (and pre L2 VMRUN) L1's state there
- L2's state is restored from SMRAM
- upon first exit L1's state is restored from L1.
This was always broken with regards to svm_get_nested_state()/
svm_set_nested_state(): 'hsave' was never a part of what's being
save and restored so migration happening during SMM triggered from L2 would
never restore L1's state correctly.
Post-split flow (broken) looks like:
- SMM is triggered during L2's execution
- L2's state is pushed to SMRAM
- nested_svm_vmexit() switches to VMCB01 from VMCB02
- SMM -> RSM
- enter_svm_guest_mode() switches from VMCB01 to VMCB02 but pre-SMM VMCB01
is already lost.
- L2's state is restored from SMRAM
- upon first exit L1's state is restored from VMCB01 but it is corrupted
(reflects the state during 'RSM' execution).
VMX doesn't have this problem because unlike VMCB, VMCS keeps both guest
and host state so when we switch back to VMCS02 L1's state is intact there.
To resolve the issue we need to save L1's state somewhere. We could've
created a third VMCB for SMM but that would require us to modify saved
state format. L1's architectural HSAVE area (pointed by MSR_VM_HSAVE_PA)
seems appropriate: L0 is free to save any (or none) of L1's state there.
Currently, KVM does 'none'.
Note, for nested state migration to succeed, both source and destination
hypervisors must have the fix. We, however, don't need to create a new
flag indicating the fact that HSAVE area is now populated as migration
during SMM triggered from L2 was always broken.
Fixes: 4995a3685f ("KVM: SVM: Use a separate vmcb for the nested L2 guest")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Separate the code setting non-VMLOAD-VMSAVE state from
svm_set_nested_state() into its own function. This is going to be
re-used from svm_enter_smm()/svm_leave_smm().
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210628104425.391276-4-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APM states that "The address written to the VM_HSAVE_PA MSR, which holds
the address of the page used to save the host state on a VMRUN, must point
to a hypervisor-owned page. If this check fails, the WRMSR will fail with
a #GP(0) exception. Note that a value of 0 is not considered valid for the
VM_HSAVE_PA MSR and a VMRUN that is attempted while the HSAVE_PA is 0 will
fail with a #GP(0) exception."
svm_set_msr() already checks that the supplied address is valid, so only
check for '0' is missing. Add it to nested_svm_vmrun().
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210628104425.391276-3-vkuznets@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APM states that #GP is raised upon write to MSR_VM_HSAVE_PA when
the supplied address is not page-aligned or is outside of "maximum
supported physical address for this implementation".
page_address_valid() check seems suitable. Also, forcefully page-align
the address when it's written from VMM.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210628104425.391276-2-vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
[Add comment about behavior for host-provided values. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In theory there are no side effects of not intercepting #SMI,
because then #SMI becomes transparent to the OS and the KVM.
Plus an observation on recent Zen2 CPUs reveals that these
CPUs ignore #SMI interception and never deliver #SMI VMexits.
This is also useful to test nested KVM to see that L1
handles #SMIs correctly in case when L1 doesn't intercept #SMI.
Finally the default remains the same, the SMI are intercepted
by default thus this patch doesn't have any effect unless
non default module param value is used.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210707125100.677203-4-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Kernel never sends real INIT even to CPUs, other than on boot.
Thus INIT interception is an error which should be caught
by a check for an unknown VMexit reason.
On top of that, the current INIT VM exit handler skips
the current instruction which is wrong.
That was added in commit 5ff3a351f6 ("KVM: x86: Move trivial
instruction-based exit handlers to common code").
Fixes: 5ff3a351f6 ("KVM: x86: Move trivial instruction-based exit handlers to common code")
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210707125100.677203-3-mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 5ff3a351f6 ("KVM: x86: Move trivial instruction-based
exit handlers to common code"), unfortunately made a mistake of
treating nop_on_interception and nop_interception in the same way.
Former does truly nothing while the latter skips the instruction.
SMI VM exit handler should do nothing.
(SMI itself is handled by the host when we do STGI)
Fixes: 5ff3a351f6 ("KVM: x86: Move trivial instruction-based exit handlers to common code")
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210707125100.677203-2-mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
vmx_msr_index was used to record the list of MSRs which can be lazily
restored when kvm returns to userspace. It is now reimplemented as
kvm_uret_msrs_list, a common x86 list which is only used inside x86.c.
So just remove the obsolete declaration in vmx.h.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Message-Id: <20210707235702.31595-1-yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When the host is using debug registers but the guest is not using them
nor is the guest in guest-debug state, the kvm code does not reset
the host debug registers before kvm_x86->run(). Rather, it relies on
the hardware vmentry instruction to automatically reset the dr7 registers
which ensures that the host breakpoints do not affect the guest.
This however violates the non-instrumentable nature around VM entry
and exit; for example, when a host breakpoint is set on vcpu->arch.cr2,
Another issue is consistency. When the guest debug registers are active,
the host breakpoints are reset before kvm_x86->run(). But when the
guest debug registers are inactive, the host breakpoints are delayed to
be disabled. The host tracing tools may see different results depending
on what the guest is doing.
To fix the problems, we clear %db7 unconditionally before kvm_x86->run()
if the host has set any breakpoints, no matter if the guest is using
them or not.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20210628172632.81029-1-jiangshanlai@gmail.com>
Cc: stable@vger.kernel.org
[Only clear %db7 instead of reloading all debug registers. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull networking fixes from Jakub Kicinski.
"Including fixes from bpf and netfilter.
Current release - regressions:
- sock: fix parameter order in sock_setsockopt()
Current release - new code bugs:
- netfilter: nft_last:
- fix incorrect arithmetic when restoring last used
- honor NFTA_LAST_SET on restoration
Previous releases - regressions:
- udp: properly flush normal packet at GRO time
- sfc: ensure correct number of XDP queues; don't allow enabling the
feature if there isn't sufficient resources to Tx from any CPU
- dsa: sja1105: fix address learning getting disabled on the CPU port
- mptcp: addresses a rmem accounting issue that could keep packets in
subflow receive buffers longer than necessary, delaying MPTCP-level
ACKs
- ip_tunnel: fix mtu calculation for ETHER tunnel devices
- do not reuse skbs allocated from skbuff_fclone_cache in the napi
skb cache, we'd try to return them to the wrong slab cache
- tcp: consistently disable header prediction for mptcp
Previous releases - always broken:
- bpf: fix subprog poke descriptor tracking use-after-free
- ipv6:
- allocate enough headroom in ip6_finish_output2() in case
iptables TEE is used
- tcp: drop silly ICMPv6 packet too big messages to avoid
expensive and pointless lookups (which may serve as a DDOS
vector)
- make sure fwmark is copied in SYNACK packets
- fix 'disable_policy' for forwarded packets (align with IPv4)
- netfilter: conntrack:
- do not renew entry stuck in tcp SYN_SENT state
- do not mark RST in the reply direction coming after SYN packet
for an out-of-sync entry
- mptcp: cleanly handle error conditions with MP_JOIN and syncookies
- mptcp: fix double free when rejecting a join due to port mismatch
- validate lwtstate->data before returning from skb_tunnel_info()
- tcp: call sk_wmem_schedule before sk_mem_charge in zerocopy path
- mt76: mt7921: continue to probe driver when fw already downloaded
- bonding: fix multiple issues with offloading IPsec to (thru?) bond
- stmmac: ptp: fix issues around Qbv support and setting time back
- bcmgenet: always clear wake-up based on energy detection
Misc:
- sctp: move 198 addresses from unusable to private scope
- ptp: support virtual clocks and timestamping
- openvswitch: optimize operation for key comparison"
* tag 'net-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (158 commits)
net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave()
sfc: add logs explaining XDP_TX/REDIRECT is not available
sfc: ensure correct number of XDP queues
sfc: fix lack of XDP TX queues - error XDP TX failed (-22)
net: fddi: fix UAF in fza_probe
net: dsa: sja1105: fix address learning getting disabled on the CPU port
net: ocelot: fix switchdev objects synced for wrong netdev with LAG offload
net: Use nlmsg_unicast() instead of netlink_unicast()
octeontx2-pf: Fix uninitialized boolean variable pps
ipv6: allocate enough headroom in ip6_finish_output2()
net: hdlc: rename 'mod_init' & 'mod_exit' functions to be module-specific
net: bridge: multicast: fix MRD advertisement router port marking race
net: bridge: multicast: fix PIM hello router port marking race
net: phy: marvell10g: fix differentiation of 88X3310 from 88X3340
dsa: fix for_each_child.cocci warnings
virtio_net: check virtqueue_add_sgs() return value
mptcp: properly account bulk freed memory
selftests: mptcp: fix case multiple subflows limited by server
mptcp: avoid processing packet if a subflow reset
mptcp: fix syncookie process if mptcp can not_accept new subflow
...
