The kvm_pmu_refresh() may be called repeatedly (e.g. configure guest
CPUID repeatedly or update MSR_IA32_PERF_CAPABILITIES) and each
call will use the last pmu->all_valid_pmc_idx value, with the residual
bits introducing additional overhead later in the vPMU emulation.
Fixes: b35e5548b4 ("KVM: x86/vPMU: Add lazy mechanism to release perf_event per vPMC")
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Like Xu <likexu@tencent.com>
Link: https://lore.kernel.org/r/20230404071759.75376-1-likexu@tencent.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM functions use "long" return values for functions that are wired up
to "struct file_operations", but otherwise use "int" return values for
functions that can return 0/-errno in order to avoid unintentional
divergences between 32-bit and 64-bit kernels.
Some code still uses "long" in unnecessary spots, though, which can
cause a little bit of confusion and unnecessary size casts. Let's
change these spots to use "int" types, too.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230208140105.655814-6-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In case of success, this function returns the amount of handled bytes.
However, this does not work for large values: The function is called
from kvm_arch_vm_ioctl() (which still returns a long), which in turn
is called from kvm_vm_ioctl() in virt/kvm/kvm_main.c. And that function
stores the return value in an "int r" variable. So the upper 32-bits
of the "long" return value are lost there.
KVM ioctl functions should only return "int" values, so let's limit
the amount of bytes that can be requested here to INT_MAX to avoid
the problem with the truncated return value. We can then also change
the return type of the function to "int" to make it clearer that it
is not possible to return a "long" here.
Fixes: f0376edb1d ("KVM: arm64: Add ioctl to fetch/store tags in a guest")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Message-Id: <20230208140105.655814-5-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The KVM_GET_NR_MMU_PAGES ioctl is quite questionable on 64-bit hosts
since it fails to return the full 64 bits of the value that can be
set with the corresponding KVM_SET_NR_MMU_PAGES call. Its "long" return
value is truncated into an "int" in the kvm_arch_vm_ioctl() function.
Since this ioctl also never has been used by userspace applications
(QEMU, Google's internal VMM, kvmtool and CrosVM have been checked),
it's likely the best if we remove this badly designed ioctl before
anybody really tries to use it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230208140105.655814-4-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Most functions that are related to kvm_arch_vm_ioctl() already use
"int" as return type to pass error values back to the caller. Some
outlier functions use "long" instead for no good reason (they do not
really require long values here). Let's standardize on "int" here to
avoid casting the values back and forth between the two types.
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230208140105.655814-2-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
FLUSH_L1D was already added in 11e34e64e4, but the feature is not
visible to userspace yet.
The bit definition:
CPUID.(EAX=7,ECX=0):EDX[bit 28]
If the feature is supported by the host, kvm should support it too so
that userspace can choose whether to expose it to the guest or not.
One disadvantage of not exposing it is that the guest will report
a non existing vulnerability in
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
because the mitigation is present only if the guest supports
(FLUSH_L1D and MD_CLEAR) or FB_CLEAR.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201132905.549148-4-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Expose IA32_FLUSH_CMD to the guest if the guest CPUID enumerates
support for this MSR. As with IA32_PRED_CMD, permission for
unintercepted writes to this MSR will be granted to the guest after
the first non-zero write.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201132905.549148-3-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Expose IA32_FLUSH_CMD to the guest if the guest CPUID enumerates
support for this MSR. As with IA32_PRED_CMD, permission for
unintercepted writes to this MSR will be granted to the guest after
the first non-zero write.
Co-developed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201132905.549148-2-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Rename enable_evmcs to __kvm_is_using_evmcs to match its wrapper, and to
avoid confusion with enabling eVMCS for nested virtualization, i.e. have
"enable eVMCS" be reserved for "enable eVMCS support for L1".
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230211003534.564198-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Wrap enable_evmcs in a helper and stub it out when CONFIG_HYPERV=n in
order to eliminate the static branch nop placeholders. clang-14 is clever
enough to elide the nop, but gcc-12 is not. Stubbing out the key reduces
the size of kvm-intel.ko by ~7.5% (200KiB) when compiled with gcc-12
(there are a _lot_ of VMCS accesses throughout KVM).
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230211003534.564198-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the macros that define the set of VMCS controls that are supported
by eVMCS1 from hyperv.h to hyperv.c, i.e. make them "private". The
macros should never be consumed directly by KVM at-large since the "final"
set of supported controls depends on guest CPUID.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230211003534.564198-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Drop FNAME(is_self_change_mapping) and instead rely on
kvm_mmu_hugepage_adjust() to adjust the hugepage accordingly. Prior to
commit 4cd071d13c ("KVM: x86/mmu: Move calls to thp_adjust() down a
level"), the hugepage adjustment was done before allocating new shadow
pages, i.e. failed to restrict the hugepage sizes if a new shadow page
resulted in account_shadowed() changing the disallowed hugepage tracking.
Removing FNAME(is_self_change_mapping) fixes a bug reported by Huang Hang
where KVM unnecessarily forces a 4KiB page. FNAME(is_self_change_mapping)
has a defect in that it blindly disables _all_ hugepage mappings rather
than trying to reduce the size of the hugepage. If the guest is writing
to a 1GiB page and the 1GiB is self-referential but a 2MiB page is not,
then KVM can and should create a 2MiB mapping.
Add a comment above the call to kvm_mmu_hugepage_adjust() to call out the
new dependency on adjusting the hugepage size after walking indirect PTEs.
Reported-by: Huang Hang <hhuang@linux.alibaba.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Link: https://lore.kernel.org/r/20221213125538.81209-1-jiangshanlai@gmail.com
[sean: rework changelog after separating out the emulator change]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230202182817.407394-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the detection of write #PF to shadow pages, i.e. a fault on a write
to a page table that is being shadowed by KVM that is used to translate
the write itself, from FNAME(is_self_change_mapping) to FNAME(fetch).
There is no need to detect the self-referential write before
kvm_faultin_pfn() as KVM does not consume EMULTYPE_WRITE_PF_TO_SP for
accesses that resolve to "error or no-slot" pfns, i.e. KVM doesn't allow
retrying MMIO accesses or writes to read-only memslots.
Detecting the EMULTYPE_WRITE_PF_TO_SP scenario in FNAME(fetch) will allow
dropping FNAME(is_self_change_mapping) entirely, as the hugepage
interaction can be deferred to kvm_mmu_hugepage_adjust().
Cc: Huang Hang <hhuang@linux.alibaba.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Link: https://lore.kernel.org/r/20221213125538.81209-1-jiangshanlai@gmail.com
[sean: split to separate patch, write changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230202182817.407394-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use a new EMULTYPE flag, EMULTYPE_WRITE_PF_TO_SP, to track page faults
on self-changing writes to shadowed page tables instead of propagating
that information to the emulator via a semi-persistent vCPU flag. Using
a flag in "struct kvm_vcpu_arch" is confusing, especially as implemented,
as it's not at all obvious that clearing the flag only when emulation
actually occurs is correct.
E.g. if KVM sets the flag and then retries the fault without ever getting
to the emulator, the flag will be left set for future calls into the
emulator. But because the flag is consumed if and only if both
EMULTYPE_PF and EMULTYPE_ALLOW_RETRY_PF are set, and because
EMULTYPE_ALLOW_RETRY_PF is deliberately not set for direct MMUs, emulated
MMIO, or while L2 is active, KVM avoids false positives on a stale flag
since FNAME(page_fault) is guaranteed to be run and refresh the flag
before it's ultimately consumed by the tail end of reexecute_instruction().
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230202182817.407394-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The xen_shinfo_test started off with very few iterations, and the numbers
we used in GUEST_SYNC() were precisely mapped to the RUNSTATE_xxx values
anyway to start with.
It has since grown quite a few more tests, and it's kind of awful to be
handling them all as bare numbers. Especially when I want to add a new
test in the middle. Define an enum for the test stages, and use it both
in the guest code and the host switch statement.
No functional change, if I can count to 24.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230204024151.1373296-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add wrappers to do hypercalls using VMCALL/VMMCALL and Xen's register ABI
(as opposed to full Xen-style hypercalls through a hypervisor provided
page). Using the common helpers dedups a pile of code, and uses the
native hypercall instruction when running on AMD.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230204024151.1373296-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Extract the guts of kvm_hypercall() to a macro so that Xen hypercalls,
which have a different register ABI, can reuse the VMCALL vs. VMMCALL
logic.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230204024151.1373296-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
WARN if generating a GATag given a VM ID and vCPU ID doesn't yield the
same IDs when pulling the IDs back out of the tag. Don't bother adding
error handling to callers, this is very much a paranoid sanity check as
KVM fully controls the VM ID and is supposed to reject too-big vCPU IDs.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20230207002156.521736-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Define AVIC_VCPU_ID_MASK based on AVIC_PHYSICAL_MAX_INDEX, i.e. the mask
that effectively controls the largest guest physical APIC ID supported by
x2AVIC, instead of hardcoding the number of bits to 8 (and the number of
VM bits to 24).
The AVIC GATag is programmed into the AMD IOMMU IRTE to provide a
reference back to KVM in case the IOMMU cannot inject an interrupt into a
non-running vCPU. In such a case, the IOMMU notifies software by creating
a GALog entry with the corresponded GATag, and KVM then uses the GATag to
find the correct VM+vCPU to kick. Dropping bit 8 from the GATag results
in kicking the wrong vCPU when targeting vCPUs with x2APIC ID > 255.
Fixes: 4d1d7942e3 ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode")
Cc: stable@vger.kernel.org
Reported-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20230207002156.521736-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Define the "physical table max index mask" as bits 8:0, not 9:0. x2AVIC
currently supports a max of 512 entries, i.e. the max index is 511, and
the inputs to GENMASK_ULL() are inclusive. The bug is benign as bit 9 is
reserved and never set by KVM, i.e. KVM is just clearing bits that are
guaranteed to be zero.
Note, as of this writing, APM "Rev. 3.39-October 2022" incorrectly states
that bits 11:8 are reserved in Table B-1. VMCB Layout, Control Area. I.e.
that table wasn't updated when x2AVIC support was added.
Opportunistically fix the comment for the max AVIC ID to align with the
code, and clean up comment formatting too.
Fixes: 4d1d7942e3 ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode")
Cc: stable@vger.kernel.org
Cc: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20230207002156.521736-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now, if KVM memory stress tests are run with hugetlb sources but hugetlb is
not available (either in the kernel or because /proc/sys/vm/nr_hugepages is 0)
the test will fail with a memory allocation error.
This makes it impossible to add tests that default to hugetlb-backed memory,
because on a machine with a default configuration they will fail. Therefore,
check HugePages_Total as well and, if zero, direct the user to enable hugepages
in procfs. Furthermore, return KSFT_SKIP whenever hugetlb is not available.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
nested_vmx_check_controls() has already run by the time KVM checks host state,
so the "host address space size" exit control can only be set on x86-64 hosts.
Simplify the condition at the cost of adding some dead code to 32-bit kernels.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The effective values of the guest CR0 and CR4 registers may differ from
those included in the VMCS12. In particular, disabling EPT forces
CR4.PAE=1 and disabling unrestricted guest mode forces CR0.PG=CR0.PE=1.
Therefore, checks on these bits cannot be delegated to the processor
and must be performed by KVM.
Reported-by: Reima ISHII <ishiir@g.ecc.u-tokyo.ac.jp>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM/arm64 fixes for 6.3, part #1
A single patch to address a rather annoying bug w.r.t. guest timer
offsetting. Effectively the synchronization of timer offsets between
vCPUs was broken, leading to inconsistent timer reads within the VM.
Pull tpm fixes from Jarkko Sakkinen:
"Two additional bug fixes for v6.3"
* tag 'tpm-v6.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
tpm: disable hwrng for fTPM on some AMD designs
tpm/eventlog: Don't abort tpm_read_log on faulty ACPI address
AMD has issued an advisory indicating that having fTPM enabled in
BIOS can cause "stuttering" in the OS. This issue has been fixed
in newer versions of the fTPM firmware, but it's up to system
designers to decide whether to distribute it.
This issue has existed for a while, but is more prevalent starting
with kernel 6.1 because commit b006c439d5 ("hwrng: core - start
hwrng kthread also for untrusted sources") started to use the fTPM
for hwrng by default. However, all uses of /dev/hwrng result in
unacceptable stuttering.
So, simply disable registration of the defective hwrng when detecting
these faulty fTPM versions. As this is caused by faulty firmware, it
is plausible that such a problem could also be reproduced by other TPM
interactions, but this hasn't been shown by any user's testing or reports.
It is hypothesized to be triggered more frequently by the use of the RNG
because userspace software will fetch random numbers regularly.
Intentionally continue to register other TPM functionality so that users
that rely upon PCR measurements or any storage of data will still have
access to it. If it's found later that another TPM functionality is
exacerbating this problem a module parameter it can be turned off entirely
and a module parameter can be introduced to allow users who rely upon
fTPM functionality to turn it on even though this problem is present.
Link: https://www.amd.com/en/support/kb/faq/pa-410
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216989
Link: https://lore.kernel.org/all/20230209153120.261904-1-Jason@zx2c4.com/
Fixes: b006c439d5 ("hwrng: core - start hwrng kthread also for untrusted sources")
Cc: stable@vger.kernel.org
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Tested-by: reach622@mailcuk.com
Tested-by: Bell <1138267643@qq.com>
Co-developed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Pull xfs fixes from Darrick Wong:
- Fix a crash if mount time quotacheck fails when there are inodes
queued for garbage collection.
- Fix an off by one error when discarding folios after writeback
failure.
* tag 'xfs-6.3-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix off-by-one-block in xfs_discard_folio()
xfs: quotacheck failure can race with background inode inactivation
Pull staging driver fixes and removal from Greg KH:
"Here are four small staging driver fixes, and one big staging driver
deletion for 6.3-rc2.
The fixes are:
- rtl8192e driver fixes for where the driver was attempting to
execute various programs directly from the disk for unknown reasons
- rtl8723bs driver fixes for issues found by Hans in testing
The deleted driver is the removal of the r8188eu wireless driver as
now in 6.3-rc1 we have a "real" wifi driver for one that includes
support for many many more devices than this old driver did. So it's
time to remove it as it is no longer needed. The maintainers of this
driver all have acked its removal. Many thanks to them over the years
for working to clean it up and keep it working while the real driver
was being developed.
All of these have been in linux-next this week with no reported
problems"
* tag 'staging-6.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: r8188eu: delete driver
staging: rtl8723bs: Pass correct parameters to cfg80211_get_bss()
staging: rtl8723bs: Fix key-store index handling
staging: rtl8192e: Remove call_usermodehelper starting RadioPower.sh
staging: rtl8192e: Remove function ..dm_check_ac_dc_power calling a script
Pull x86 fix from Borislav Petkov:
"A single erratum fix for AMD machines:
- Disable XSAVES on AMD Zen1 and Zen2 machines due to an erratum. No
impact to anything as those machines will fallback to XSAVEC which
is equivalent there"
* tag 'x86_urgent_for_v6.3_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU/AMD: Disable XSAVES on AMD family 0x17
Pull clone3 fix from Christian Brauner:
"A simple fix for the clone3() system call.
The CLONE_NEWTIME allows the creation of time namespaces. The flag
reuses a bit from the CSIGNAL bits that are used in the legacy clone()
system call to set the signal that gets sent to the parent after the
child exits.
The clone3() system call doesn't rely on CSIGNAL anymore as it uses a
dedicated .exit_signal field in struct clone_args. So we blocked all
CSIGNAL bits in clone3_args_valid(). When CLONE_NEWTIME was introduced
and reused a CSIGNAL bit we forgot to adapt clone3_args_valid()
causing CLONE_NEWTIME with clone3() to be rejected. Fix this"
* tag 'kernel.fork.v6.3-rc2' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux:
selftests/clone3: test clone3 with CLONE_NEWTIME
fork: allow CLONE_NEWTIME in clone3 flags
Pull vfs fixes from Christian Brauner:
- When allocating pages for a watch queue failed, we didn't return an
error causing userspace to proceed even though all subsequent
notifcations would be lost. Make sure to return an error.
- Fix a misformed tree entry for the idmapping maintainers entry.
- When setting file leases from an idmapped mount via
generic_setlease() we need to take the idmapping into account
otherwise taking a lease would fail from an idmapped mount.
- Remove two redundant assignments, one in splice code and the other in
locks code, that static checkers complained about.
* tag 'vfs.misc.v6.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping:
filelocks: use mount idmapping for setlease permission check
fs/locks: Remove redundant assignment to cmd
splice: Remove redundant assignment to ret
MAINTAINERS: repair a malformed T: entry in IDMAPPED MOUNTS
watch_queue: fix IOC_WATCH_QUEUE_SET_SIZE alloc error paths
Pull ext4 fixes from Ted Ts'o:
"Bug fixes and regressions for ext4, the most serious of which is a
potential deadlock during directory renames that was introduced during
the merge window discovered by a combination of syzbot and lockdep"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: zero i_disksize when initializing the bootloader inode
ext4: make sure fs error flag setted before clear journal error
ext4: commit super block if fs record error when journal record without error
ext4, jbd2: add an optimized bmap for the journal inode
ext4: fix WARNING in ext4_update_inline_data
ext4: move where set the MAY_INLINE_DATA flag is set
ext4: Fix deadlock during directory rename
ext4: Fix comment about the 64BIT feature
docs: ext4: modify the group desc size to 64
ext4: fix another off-by-one fsmap error on 1k block filesystems
ext4: fix RENAME_WHITEOUT handling for inline directories
ext4: make kobj_type structures constant
ext4: fix cgroup writeback accounting with fs-layer encryption
The cpumask_check() was unnecessarily tight, and causes problems for the
users of cpumask_next().
We have a number of users that take the previous return value of one of
the bit scanning functions and subtract one to keep it in "range". But
since the scanning functions end up returning up to 'small_cpumask_bits'
instead of the tighter 'nr_cpumask_bits', the range really needs to be
using that widened form.
[ This "previous-1" behavior is also the reason we have all those
comments about /* -1 is a legal arg here. */ and separate checks for
that being ok. So we could have just made "small_cpumask_bits-1"
be a similar special "don't check this" value.
Tetsuo Handa even suggested a patch that only does that for
cpumask_next(), since that seems to be the only actual case that
triggers, but that all makes it even _more_ magical and special. So
just relax the check ]
One example of this kind of pattern being the 'c_start()' function in
arch/x86/kernel/cpu/proc.c, but also duplicated in various forms on
other architectures.
Reported-by: syzbot+96cae094d90877641f32@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=96cae094d90877641f32
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Link: https://lore.kernel.org/lkml/c1f4cc16-feea-b83c-82cf-1a1f007b7eb9@I-love.SAKURA.ne.jp/
Fixes: 596ff4a09b ("cpumask: re-introduce constant-sized cpumask optimizations")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull i2c updates from Wolfram Sang:
"This marks the end of a transition to let I2C have the same probe
semantics as other subsystems. Uwe took care that no drivers in the
current tree nor in -next use the deprecated .probe call. So, it is a
good time to switch to the new, standard semantics now.
There is also a regression fix:
- regression fix for the notifier handling of the I2C core
- final coversions of drivers away from deprecated .probe
- make .probe_new the standard probe and convert I2C core to use it
* tag 'i2c-for-6.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: dev: Fix bus callback return values
i2c: Convert drivers to new .probe() callback
i2c: mux: Convert all drivers to new .probe() callback
i2c: Switch .probe() to not take an id parameter
media: i2c: ov2685: convert to i2c's .probe_new()
media: i2c: ov5695: convert to i2c's .probe_new()
w1: ds2482: Convert to i2c's .probe_new()
serial: sc16is7xx: Convert to i2c's .probe_new()
mtd: maps: pismo: Convert to i2c's .probe_new()
misc: ad525x_dpot-i2c: Convert to i2c's .probe_new()