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Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Pull kvm fixes from Paolo Bonzini:
"ARM64:
- Fix pKVM error path on init, making sure we do not change critical
system registers as we're about to fail
- Make sure that the host's vector length is at capped by a value
common to all CPUs
- Fix kvm_has_feat*() handling of "negative" features, as the current
code is pretty broken
- Promote Joey to the status of official reviewer, while James steps
down -- hopefully only temporarly
x86:
- Fix compilation with KVM_INTEL=KVM_AMD=n
- Fix disabling KVM_X86_QUIRK_SLOT_ZAP_ALL when shadow MMU is in use
Selftests:
- Fix compilation on non-x86 architectures"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
x86/reboot: emergency callbacks are now registered by common KVM code
KVM: x86: leave kvm.ko out of the build if no vendor module is requested
KVM: x86/mmu: fix KVM_X86_QUIRK_SLOT_ZAP_ALL for shadow MMU
KVM: arm64: Fix kvm_has_feat*() handling of negative features
KVM: selftests: Fix build on architectures other than x86_64
KVM: arm64: Another reviewer reshuffle
KVM: arm64: Constrain the host to the maximum shared SVE VL with pKVM
KVM: arm64: Fix __pkvm_init_vcpu cptr_el2 error path
Pull powerpc fix from Michael Ellerman:
- Allow r30 to be used in vDSO code generation of getrandom
Thanks to Jason A. Donenfeld
* tag 'powerpc-6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/vdso: allow r30 in vDSO code generation of getrandom
KVM/arm64 fixes for 6.12, take #1
- Fix pKVM error path on init, making sure we do not change critical
system registers as we're about to fail
- Make sure that the host's vector length is at capped by a value
common to all CPUs
- Fix kvm_has_feat*() handling of "negative" features, as the current
code is pretty broken
- Promote Joey to the status of official reviewer, while James steps
down -- hopefully only temporarly
Pull bcachefs fixes from Kent Overstreet:
"A lot of little fixes, bigger ones include:
- bcachefs's __wait_on_freeing_inode() was broken in rc1 due to vfs
changes, now fixed along with another lost wakeup
- fragmentation LRU fixes; fsck now repairs successfully (this is the
data structure copygc uses); along with some nice simplification.
- Rework logged op error handling, so that if logged op replay errors
(due to another filesystem error) we delete the logged op instead
of going into an infinite loop)
- Various small filesystem connectivitity repair fixes"
* tag 'bcachefs-2024-10-05' of git://evilpiepirate.org/bcachefs:
bcachefs: Rework logged op error handling
bcachefs: Add warn param to subvol_get_snapshot, peek_inode
bcachefs: Kill snapshot arg to fsck_write_inode()
bcachefs: Check for unlinked, non-empty dirs in check_inode()
bcachefs: Check for unlinked inodes with dirents
bcachefs: Check for directories with no backpointers
bcachefs: Kill alloc_v4.fragmentation_lru
bcachefs: minor lru fsck fixes
bcachefs: Mark more errors AUTOFIX
bcachefs: Make sure we print error that causes fsck to bail out
bcachefs: bkey errors are only AUTOFIX during read
bcachefs: Create lost+found in correct snapshot
bcachefs: Fix reattach_inode()
bcachefs: Add missing wakeup to bch2_inode_hash_remove()
bcachefs: Fix trans_commit disk accounting revert
bcachefs: Fix bch2_inode_is_open() check
bcachefs: Fix return type of dirent_points_to_inode_nowarn()
bcachefs: Fix bad shift in bch2_read_flag_list()
For gettimeofday, -ffixed-r30 was passed to work around a bug in Go
code, where the vDSO trampoline forgot to save and restore this register
across function calls. But Go requires a different trampoline for every
call, and there's no reason that new Go code needs to be broken and add
more bugs. So remove -ffixed-r30 for getrandom.
Fixes: 8072b39c3a75 ("powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO64")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240925175021.1526936-2-Jason@zx2c4.com
Guard them with CONFIG_KVM_X86_COMMON rather than the two vendor modules.
In practice this has no functional change, because CONFIG_KVM_X86_COMMON
is set if and only if at least one vendor-specific module is being built.
However, it is cleaner to specify CONFIG_KVM_X86_COMMON for functions that
are used in kvm.ko.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
Fixes: 6d55a94222db ("x86/reboot: Unconditionally define cpu_emergency_virt_cb typedef")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Oliver reports that the kvm_has_feat() helper is not behaviing as
expected for negative feature. On investigation, the main issue
seems to be caused by the following construct:
#define get_idreg_field(kvm, id, fld) \
(id##_##fld##_SIGNED ? \
get_idreg_field_signed(kvm, id, fld) : \
get_idreg_field_unsigned(kvm, id, fld))
where one side of the expression evaluates as something signed,
and the other as something unsigned. In retrospect, this is totally
braindead, as the compiler converts this into an unsigned expression.
When compared to something that is 0, the test is simply elided.
Epic fail. Similar issue exists in the expand_field_sign() macro.
The correct way to handle this is to chose between signed and unsigned
comparisons, so that both sides of the ternary expression are of the
same type (bool).
In order to keep the code readable (sort of), we introduce new
comparison primitives taking an operator as a parameter, and
rewrite the kvm_has_feat*() helpers in terms of these primitives.
Fixes: c62d7a23b947 ("KVM: arm64: Add feature checking helpers")
Reported-by: Oliver Upton <oliver.upton@linux.dev>
Tested-by: Oliver Upton <oliver.upton@linux.dev>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20241002204239.2051637-1-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Pull xen fix from Juergen Gross:
"Fix Xen config issue introduced in the merge window"
* tag 'for-linus-6.12a-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: Fix config option reference in XEN_PRIVCMD definition
Initially it was thought that we just wanted to ignore errors from
logged op replay, but it turns out we do need to catch -EROFS, or we'll
go into an infinite loop.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
kvm.ko is nothing but library code shared by kvm-intel.ko and kvm-amd.ko.
It provides no functionality on its own and it is unnecessary unless one
of the vendor-specific module is compiled. In particular, /dev/kvm is
not created until one of kvm-intel.ko or kvm-amd.ko is loaded.
Use CONFIG_KVM to decide if it is built-in or a module, but use the
vendor-specific modules for the actual decision on whether to build it.
This also fixes a build failure when CONFIG_KVM_INTEL and CONFIG_KVM_AMD
are both disabled. The cpu_emergency_register_virt_callback() function
is called from kvm.ko, but it is only defined if at least one of
CONFIG_KVM_INTEL and CONFIG_KVM_AMD is provided.
Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It has been a while since James had any significant bandwidth to
review KVM/arm64 patches. But in the meantime, Joey has stepped up
and did a really good job reviewing some terrifying patch series.
Having talked with the interested parties, it appears that James
is unlikely to have time for KVM in the near future, and that Joey
is willing to take more responsibilities.
So let's appoint Joey as an official reviewer, and give James some
breathing space, as well as my personal thanks. I'm sure he will
be back one way or another!
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Zenghui Yu <yuzenghui@huawei.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Acked-by: Joey Gouly <joey.gouly@arm.com>
Acked-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20240927104956.1223658-1-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Pull ext4 fixes from Ted Ts'o:
"Fix some ext4 bugs and regressions relating to oneline resize and fast
commits"
* tag 'ext4_for_linus-5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix off by one issue in alloc_flex_gd()
ext4: mark fc as ineligible using an handle in ext4_xattr_set()
ext4: use handle to mark fc as ineligible in __track_dentry_update()
Commit 2fae6bb7be32 ("xen/privcmd: Add new syscall to get gsi from dev")
adds a weak reverse dependency to the config XEN_PRIVCMD definition,
referring to CONFIG_XEN_PCIDEV_BACKEND. In Kconfig files, one refers to
config options without the CONFIG prefix, though. So in its current form,
this does not create the reverse dependency as intended, but is an
attribute with no effect.
Refer to the intended config option XEN_PCIDEV_BACKEND in the XEN_PRIVCMD
definition.
Fixes: 2fae6bb7be32 ("xen/privcmd: Add new syscall to get gsi from dev")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Message-ID: <20240930090650.429813-1-lukas.bulwahn@redhat.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
These shouldn't always be fatal errors - logged op resume, in
particular, and we want it as a parameter there.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The cpu_emergency_register_virt_callback() function is used
unconditionally by the x86 kvm code, but it is declared (and defined)
conditionally:
#if IS_ENABLED(CONFIG_KVM_INTEL) || IS_ENABLED(CONFIG_KVM_AMD)
void cpu_emergency_register_virt_callback(cpu_emergency_virt_cb *callback);
...
leading to a build error when neither KVM_INTEL nor KVM_AMD support is
enabled:
arch/x86/kvm/x86.c: In function ‘kvm_arch_enable_virtualization’:
arch/x86/kvm/x86.c:12517:9: error: implicit declaration of function ‘cpu_emergency_register_virt_callback’ [-Wimplicit-function-declaration]
12517 | cpu_emergency_register_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/kvm/x86.c: In function ‘kvm_arch_disable_virtualization’:
arch/x86/kvm/x86.c:12522:9: error: implicit declaration of function ‘cpu_emergency_unregister_virt_callback’ [-Wimplicit-function-declaration]
12522 | cpu_emergency_unregister_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix the build by defining empty helper functions the same way the old
cpu_emergency_disable_virtualization() function was dealt with for the
same situation.
Maybe we could instead have made the call sites conditional, since the
callers (kvm_arch_{en,dis}able_virtualization()) have an empty weak
fallback. I'll leave that to the kvm people to argue about, this at
least gets the build going for that particular config.
Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Kai Huang <kai.huang@intel.com>
Cc: Chao Gao <chao.gao@intel.com>
Cc: Farrah Chen <farrah.chen@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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