Git supports a builtin Rust diff driver [1] since v2.23.0 (2019).
It improves the choice of hunk headers in some cases, such as
diffs within methods, since those are indented in Rust within
an `impl` block, and therefore the default diff driver would
pick the outer `impl` block instead (rather than the method
where the changed code is).
For instance, with the default diff driver:
@@ -455,6 +455,8 @@ impl fmt::Write for RawFormatter {
// Amount that we can copy. `saturating_sub` ensures we get 0 if `pos` goes past `end`.
let len_to_copy = core::cmp::min(pos_new, self.end).saturating_sub(self.pos);
+ test_diff_driver();
+
if len_to_copy > 0 {
// SAFETY: If `len_to_copy` is non-zero, then we know `pos` has not gone past `end`
// yet, so it is valid for write per the type invariants.
With the Rust diff driver:
@@ -455,6 +455,8 @@ fn write_str(&mut self, s: &str) -> fmt::Result {
// Amount that we can copy. `saturating_sub` ensures we get 0 if `pos` goes past `end`.
let len_to_copy = core::cmp::min(pos_new, self.end).saturating_sub(self.pos);
+ test_diff_driver();
+
if len_to_copy > 0 {
// SAFETY: If `len_to_copy` is non-zero, then we know `pos` has not gone past `end`
// yet, so it is valid for write per the type invariants.
Thus set the `rust` diff driver for `*.rs` source files.
The Rust repository also does so since 2020 [2].
Link: https://git-scm.com/docs/gitattributes#_defining_a_custom_hunk_header [1]
Link: https://github.com/rust-lang/rust/pull/78882 [2]
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20230418233048.335281-1-ojeda@kernel.org
[ Added link to Rust repository ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is the first upgrade to the Rust toolchain since the initial Rust
merge, from 1.62.0 to 1.68.2 (i.e. the latest).
# Context
The kernel currently supports only a single Rust version [1] (rather
than a minimum) given our usage of some "unstable" Rust features [2]
which do not promise backwards compatibility.
The goal is to reach a point where we can declare a minimum version for
the toolchain. For instance, by waiting for some of the features to be
stabilized. Therefore, the first minimum Rust version that the kernel
will support is "in the future".
# Upgrade policy
Given we will eventually need to reach that minimum version, it would be
ideal to upgrade the compiler from time to time to be as close as
possible to that goal and find any issues sooner. In the extreme, we
could upgrade as soon as a new Rust release is out. Of course, upgrading
so often is in stark contrast to what one normally would need for GCC
and LLVM, especially given the release schedule: 6 weeks for Rust vs.
half a year for LLVM and a year for GCC.
Having said that, there is no particular advantage to updating slowly
either: kernel developers in "stable" distributions are unlikely to be
able to use their distribution-provided Rust toolchain for the kernel
anyway [3]. Instead, by routinely upgrading to the latest instead,
kernel developers using Linux distributions that track the latest Rust
release may be able to use those rather than Rust-provided ones,
especially if their package manager allows to pin / hold back /
downgrade the version for some days during windows where the version may
not match. For instance, Arch, Fedora, Gentoo and openSUSE all provide
and track the latest version of Rust as they get released every 6 weeks.
Then, when the minimum version is reached, we will stop upgrading and
decide how wide the window of support will be. For instance, a year of
Rust versions. We will probably want to start small, and then widen it
over time, just like the kernel did originally for LLVM, see commit
3519c4d6e0 ("Documentation: add minimum clang/llvm version").
# Unstable features stabilized
This upgrade allows us to remove the following unstable features since
they were stabilized:
- `feature(explicit_generic_args_with_impl_trait)` (1.63).
- `feature(core_ffi_c)` (1.64).
- `feature(generic_associated_types)` (1.65).
- `feature(const_ptr_offset_from)` (1.65, *).
- `feature(bench_black_box)` (1.66, *).
- `feature(pin_macro)` (1.68).
The ones marked with `*` apply only to our old `rust` branch, not
mainline yet, i.e. only for code that we may potentially upstream.
With this patch applied, the only unstable feature allowed to be used
outside the `kernel` crate is `new_uninit`, though other code to be
upstreamed may increase the list.
Please see [2] for details.
# Other required changes
Since 1.63, `rustdoc` triggers the `broken_intra_doc_links` lint for
links pointing to exported (`#[macro_export]`) `macro_rules`. An issue
was opened upstream [4], but it turns out it is intended behavior. For
the moment, just add an explicit reference for each link. Later we can
revisit this if `rustdoc` removes the compatibility measure.
Nevertheless, this was helpful to discover a link that was pointing to
the wrong place unintentionally. Since that one was actually wrong, it
is fixed in a previous commit independently.
Another change was the addition of `cfg(no_rc)` and `cfg(no_sync)` in
upstream [5], thus remove our original changes for that.
Similarly, upstream now tests that it compiles successfully with
`#[cfg(not(no_global_oom_handling))]` [6], which allow us to get rid
of some changes, such as an `#[allow(dead_code)]`.
In addition, remove another `#[allow(dead_code)]` due to new uses
within the standard library.
Finally, add `try_extend_trusted` and move the code in `spec_extend.rs`
since upstream moved it for the infallible version.
# `alloc` upgrade and reviewing
There are a large amount of changes, but the vast majority of them are
due to our `alloc` fork being upgraded at once.
There are two kinds of changes to be aware of: the ones coming from
upstream, which we should follow as closely as possible, and the updates
needed in our added fallible APIs to keep them matching the newer
infallible APIs coming from upstream.
Instead of taking a look at the diff of this patch, an alternative
approach is reviewing a diff of the changes between upstream `alloc` and
the kernel's. This allows to easily inspect the kernel additions only,
especially to check if the fallible methods we already have still match
the infallible ones in the new version coming from upstream.
Another approach is reviewing the changes introduced in the additions in
the kernel fork between the two versions. This is useful to spot
potentially unintended changes to our additions.
To apply these approaches, one may follow steps similar to the following
to generate a pair of patches that show the differences between upstream
Rust and the kernel (for the subset of `alloc` we use) before and after
applying this patch:
# Get the difference with respect to the old version.
git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
cut -d/ -f3- |
grep -Fv README.md |
xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
git -C linux diff --patch-with-stat --summary -R > old.patch
git -C linux restore rust/alloc
# Apply this patch.
git -C linux am rust-upgrade.patch
# Get the difference with respect to the new version.
git -C rust checkout $(linux/scripts/min-tool-version.sh rustc)
git -C linux ls-tree -r --name-only HEAD -- rust/alloc |
cut -d/ -f3- |
grep -Fv README.md |
xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH
git -C linux diff --patch-with-stat --summary -R > new.patch
git -C linux restore rust/alloc
Now one may check the `new.patch` to take a look at the additions (first
approach) or at the difference between those two patches (second
approach). For the latter, a side-by-side tool is recommended.
Link: https://rust-for-linux.com/rust-version-policy [1]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [2]
Link: https://lore.kernel.org/rust-for-linux/CANiq72mT3bVDKdHgaea-6WiZazd8Mvurqmqegbe5JZxVyLR8Yg@mail.gmail.com/ [3]
Link: https://github.com/rust-lang/rust/issues/106142 [4]
Link: https://github.com/rust-lang/rust/pull/89891 [5]
Link: https://github.com/rust-lang/rust/pull/98652 [6]
Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-By: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Tested-by: Ariel Miculas <amiculas@cisco.com>
Tested-by: David Gow <davidgow@google.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20230418214347.324156-4-ojeda@kernel.org
[ Removed `feature(core_ffi_c)` from `uapi` ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`Arc<T>::init` refers to `Arc<T>::pin_init` via an intra-doc link
using the text `pin_init`, rather than more explicitly, which makes
`rustdoc` point it to the `pin_init!` macro instead.
This is required for the compiler upgrade since the newer `rustdoc`
would trigger the `broken_intra_doc_links` lint [1], but in this case
the macro was not the intended target to begin with, and so the actual
fix is to make it point to the right place, regardless of the upgrade.
Thus make it more explicit.
Fixes: 92c4a1e7e8 ("rust: init/sync: add `InPlaceInit` trait to pin-initialize smart pointers")
Link: https://github.com/rust-lang/rust/issues/106142 [1]
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Tested-by: Ariel Miculas <amiculas@cisco.com>
Tested-by: David Gow <davidgow@google.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20230418214347.324156-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Pull x86 cpu fix from Thomas Gleixner:
"A single fix for x86:
- Prevent a bogus setting for the number of HT siblings, which is
caused by the CPUID evaluation trainwreck of X86. That recomputes
the value for each CPU, so the last CPU "wins". That can cause
completely bogus sibling values"
* tag 'x86-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology: Fix erroneous smp_num_siblings on Intel Hybrid platforms
Pull perf fixes from Thomas Gleixner:
"A small set of perf fixes:
- Make the MSR-readout based CHA discovery work around broken
discovery tables in some SPR firmwares.
- Prevent saving PEBS configuration which has software bits set that
cause a crash when restored into the relevant MSR"
* tag 'perf-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/uncore: Correct the number of CHAs on SPR
perf/x86/intel: Save/restore cpuc->active_pebs_data_cfg when using guest PEBS
Pull unwinder fixes from Thomas Gleixner:
"A set of unwinder and tooling fixes:
- Ensure that the stack pointer on x86 is aligned again so that the
unwinder does not read past the end of the stack
- Discard .note.gnu.property section which has a pointlessly
different alignment than the other note sections. That confuses
tooling of all sorts including readelf, libbpf and pahole"
* tag 'objtool-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/show_trace_log_lvl: Ensure stack pointer is aligned, again
vmlinux.lds.h: Discard .note.gnu.property section
Pull debugobjects fixes from Thomas Gleixner:
"Two fixes for debugobjects:
- Prevent the allocation path from waking up kswapd.
That's a long standing issue due to the GFP_ATOMIC allocation flag.
As debug objects can be invoked from pretty much any context waking
kswapd can end up in arbitrary lock chains versus the waitqueue
lock
- Correct the explicit lockdep wait-type violation in
debug_object_fill_pool()"
* tag 'core-debugobjects-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
debugobjects: Don't wake up kswapd from fill_pool()
debugobjects,locking: Annotate debug_object_fill_pool() wait type violation
Pull irq fixes from Thomas Gleixner:
"A set of fixes for interrupt chip drivers:
- Prevent loss of state in the MIPS GIC interrupt controller
- Disable pseudo NMIs on Mediatek based Chromebooks as they have
firmware issues which cause instantenous chrashes and freezes wen
pseudo NMIs are used
- Fix the error handling path in the MBIGEN driver and a defined but
not used warning in the meson-gpio interrupt chip driver"
* tag 'irq-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/mbigen: Unify the error handling in mbigen_of_create_domain()
irqchip/meson-gpio: Mark OF related data as maybe unused
irqchip/mips-gic: Use raw spinlock for gic_lock
irqchip/mips-gic: Don't touch vl_map if a local interrupt is not routable
irqchip/gic-v3: Disable pseudo NMIs on Mediatek devices w/ firmware issues
dt-bindings: interrupt-controller: arm,gic-v3: Add quirk for Mediatek SoCs w/ broken FW
Pull MIPS fixes from Thomas Bogendoerfer:
- fixes to get alchemy platform back in shape
- fix for initrd detection
* tag 'mips-fixes_6.4_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
mips: Move initrd_start check after initrd address sanitisation.
MIPS: Alchemy: fix dbdma2
MIPS: Restore Au1300 support
MIPS: unhide PATA_PLATFORM
Pull powerpc fix from Michael Ellerman:
- Reinstate ARCH_FORCE_MAX_ORDER ranges to fix various breakage
* tag 'powerpc-6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm: Reinstate ARCH_FORCE_MAX_ORDER ranges
Pull xen fixes from Juergen Gross:
- a double free fix in the Xen pvcalls backend driver
- a fix for a regression causing the MSI related sysfs entries to not
being created in Xen PV guests
- a fix in the Xen blkfront driver for handling insane input data
better
* tag 'for-linus-6.4-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/pci/xen: populate MSI sysfs entries
xen/pvcalls-back: fix double frees with pvcalls_new_active_socket()
xen/blkfront: Only check REQ_FUA for writes
Pull char/misc fixes from Greg KH:
"Here are some small driver fixes for 6.4-rc4. They are just two
different types:
- binder fixes and reverts for reported problems and regressions in
the binder "driver".
- coresight driver fixes for reported problems.
All of these have been in linux-next for over a week with no reported
problems"
* tag 'char-misc-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
binder: fix UAF of alloc->vma in race with munmap()
binder: add lockless binder_alloc_(set|get)_vma()
Revert "android: binder: stop saving a pointer to the VMA"
Revert "binder_alloc: add missing mmap_lock calls when using the VMA"
binder: fix UAF caused by faulty buffer cleanup
coresight: perf: Release Coresight path when alloc trace id failed
coresight: Fix signedness bug in tmc_etr_buf_insert_barrier_packet()
Pull compute express link fixes from Dan Williams:
"The 'media ready' series prevents the driver from acting on bad
capacity information, and it moves some checks earlier in the init
sequence which impacts topics in the queue for 6.5.
Additional hotplug testing uncovered a missing enable for memory
decode. A debug crash fix is also included.
Summary:
- Stop trusting capacity data before the "media ready" indication
- Add missing HDM decoder capability enable for the cold-plug case
- Fix a debug message induced crash"
* tag 'cxl-fixes-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl: Explicitly initialize resources when media is not ready
cxl/port: Fix NULL pointer access in devm_cxl_add_port()
cxl: Move cxl_await_media_ready() to before capacity info retrieval
cxl: Wait Memory_Info_Valid before access memory related info
cxl/port: Enable the HDM decoder capability for switch ports
Pull ARM SoC fixes from Arnd Bergmann:
"There have not been a lot of fixes for for the soc tree in 6.4, but
these have been sitting here for too long.
For the devicetree side, there is one minor warning fix for vexpress,
the rest all all for the the NXP i.MX platforms: SoC specific bugfixes
for the iMX8 clocks and its USB-3.0 gadget device, as well as board
specific fixes for regulators and the phy on some of the i.MX boards.
The microchip risc-v and arm32 maintainers now also add a shared
maintainer file entry for the arm64 parts.
The remaining fixes are all for firmware drivers, addressing mistakes
in the optee, scmi and ff-a firmware driver implementation, mostly in
the error handling code, incorrect use of the alloc_workqueue()
interface in SCMI, and compatibility with corner cases of the firmware
implementation"
* tag 'arm-fixes-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
MAINTAINERS: update arm64 Microchip entries
arm64: dts: imx8: fix USB 3.0 Gadget Failure in QM & QXPB0 at super speed
dt-binding: cdns,usb3: Fix cdns,on-chip-buff-size type
arm64: dts: colibri-imx8x: delete adc1 and dsp
arm64: dts: colibri-imx8x: fix iris pinctrl configuration
arm64: dts: colibri-imx8x: move pinctrl property from SoM to eval board
arm64: dts: colibri-imx8x: fix eval board pin configuration
arm64: dts: imx8mp: Fix video clock parents
ARM: dts: imx6qdl-mba6: Add missing pvcie-supply regulator
ARM: dts: imx6ull-dhcor: Set and limit the mode for PMIC buck 1, 2 and 3
arm64: dts: imx8mn-var-som: fix PHY detection bug by adding deassert delay
arm64: dts: imx8mn: Fix video clock parents
firmware: arm_ffa: Set reserved/MBZ fields to zero in the memory descriptors
firmware: arm_ffa: Fix FFA device names for logical partitions
firmware: arm_ffa: Fix usage of partition info get count flag
firmware: arm_ffa: Check if ffa_driver remove is present before executing
arm64: dts: arm: add missing cache properties
ARM: dts: vexpress: add missing cache properties
firmware: arm_scmi: Fix incorrect alloc_workqueue() invocation
optee: fix uninited async notif value
Pull PCI fix from Bjorn Helgaas:
- Quirk Ice Lake Root Ports to work around DPC log size issue (Mika
Westerberg)
* tag 'pci-v6.4-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
PCI/DPC: Quirk PIO log size for Intel Ice Lake Root Ports
Pull VFIO fix from Alex Williamson:
- Test for and return error for invalid pfns through the pin pages
interface (Yan Zhao)
* tag 'vfio-v6.4-rc4' of https://github.com/awilliam/linux-vfio:
vfio/type1: check pfn valid before converting to struct page
Pull block fixes from Jens Axboe:
"A few fixes for the storage side of things:
- Fix bio caching condition for passthrough IO (Anuj)
- end-of-device check fix for zero sized devices (Christoph)
- Update Paolo's email address
- NVMe pull request via Keith with a single quirk addition
- Fix regression in how wbt enablement is done (Yu)
- Fix race in active queue accounting (Tian)"
* tag 'block-6.4-2023-05-26' of git://git.kernel.dk/linux:
NVMe: Add MAXIO 1602 to bogus nid list.
block: make bio_check_eod work for zero sized devices
block: fix bio-cache for passthru IO
block, bfq: update Paolo's address in maintainer list
blk-mq: fix race condition in active queue accounting
blk-wbt: fix that wbt can't be disabled by default
Pull io_uring fix from Jens Axboe:
"Just a single fix for the conditional schedule with the SQPOLL thread,
dropping the uring_lock if we do need to reschedule"
* tag 'io_uring-6.4-2023-05-26' of git://git.kernel.dk/linux:
io_uring: unlock sqd->lock before sq thread release CPU
Pull thermal control fix from Rafael Wysocki:
"Fix a regression introduced inadvertently during the 6.3 cycle by a
commit making the Intel int340x thermal driver use sysfs_emit_at()
instead of scnprintf() (Srinivas Pandruvada)"
* tag 'thermal-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
thermal: intel: int340x: Add new line for UUID display
Pull power management fixes from Rafael Wysocki:
"Fix three issues related to the ->fast_switch callback in the AMD
P-state cpufreq driver (Gautham R. Shenoy and Wyes Karny)"
* tag 'pm-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: amd-pstate: Update policy->cur in amd_pstate_adjust_perf()
cpufreq: amd-pstate: Remove fast_switch_possible flag from active driver
cpufreq: amd-pstate: Add ->fast_switch() callback
When media is not ready do not assume that the capacity information from
the identify command is valid, i.e. ->total_bytes
->partition_align_bytes ->{volatile,persistent}_only_bytes. Explicitly
zero out the capacity resources and exit early.
Given zero-init of those fields this patch is functionally equivalent to
the prior state, but it improves readability and robustness going
forward.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168506118166.3004974.13523455340007852589.stgit@djiang5-mobl3
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull gpio fixes from Bartosz Golaszewski:
- fix incorrect output in in-tree gpio tools
- fix a shell coding issue in gpio-sim selftests
- correctly set the permissions for debugfs attributes exposed by
gpio-mockup
- fix chip name and pin count in gpio-f7188x for one of the supported
models
- fix numberspace pollution when using dynamically and statically
allocated GPIOs together
* tag 'gpio-fixes-for-v6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio-f7188x: fix chip name and pin count on Nuvoton chip
gpiolib: fix allocation of mixed dynamic/static GPIOs
gpio: mockup: Fix mode of debugfs files
selftests: gpio: gpio-sim: Fix BUG: test FAILED due to recent change
tools: gpio: fix debounce_period_us output of lsgpio
Pull btrfs fixes from David Sterba:
- handle memory allocation error in checksumming helper (reported by
syzbot)
- fix lockdep splat when aborting a transaction, add NOFS protection
around invalidate_inode_pages2 that could allocate with GFP_KERNEL
- reduce chances to hit an ENOSPC during scrub with RAID56 profiles
* tag 'for-6.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: use nofs when cleaning up aborted transactions
btrfs: handle memory allocation failure in btrfs_csum_one_bio
btrfs: scrub: try harder to mark RAID56 block groups read-only
