This is the next upgrade to the Rust toolchain, from 1.77.1 to 1.78.0
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
It is much smaller than previous upgrades, since the `alloc` fork was
dropped in commit 9d0441bab7 ("rust: alloc: remove our fork of the
`alloc` crate") [3].
# Unstable features
There have been no changes to the set of unstable features used in
our own code. Therefore, the only unstable features allowed to be used
outside the `kernel` crate is still `new_uninit`.
However, since we finally dropped our `alloc` fork [3], all the unstable
features used by `alloc` (~30 language ones, ~60 library ones) are not
a concern anymore. This reduces the maintenance burden, increases the
chances of new compiler versions working without changes and gets us
closer to the goal of supporting several compiler versions.
It also means that, ignoring non-language/library features, we are
currently left with just the few language features needed to implement the
kernel `Arc`, the `new_uninit` library feature, the `compiler_builtins`
marker and the few `no_*` `cfg`s we pass when compiling `core`/`alloc`.
Please see [4] for details.
# Required changes
## LLVM's data layout
Rust 1.77.0 (i.e. the previous upgrade) introduced a check for matching
LLVM data layouts [5]. Then, Rust 1.78.0 upgraded LLVM's bundled major
version from 17 to 18 [6], which changed the data layout in x86 [7]. Thus
update the data layout in our custom target specification for x86 so
that the compiler does not complain about the mismatch:
error: data-layout for target `target-5559158138856098584`,
`e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128`,
differs from LLVM target's `x86_64-linux-gnu` default layout,
`e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128`
In the future, the goal is to drop the custom target specifications.
Meanwhile, if we want to support other LLVM versions used in `rustc`
(e.g. for LTO), we will need to add some extra logic (e.g. conditional on
LLVM's version, or extracting the data layout from an existing built-in
target specification).
## `unused_imports`
Rust's `unused_imports` lint covers both unused and redundant imports.
Now, in 1.78.0, the lint detects more cases of redundant imports [8].
Thus one of the previous patches cleaned them up.
## Clippy's `new_without_default`
Clippy now suggests to implement `Default` even when `new()` is `const`,
since `Default::default()` may call `const` functions even if it is not
`const` itself [9]. Thus one of the previous patches implemented it.
# Other changes in Rust
Rust 1.78.0 introduced `feature(asm_goto)` [10] [11]. This feature was
discussed in the past [12].
Rust 1.78.0 introduced `feature(const_refs_to_static)` [13] to allow
referencing statics in constants and extended `feature(const_mut_refs)`
to allow raw mutable pointers in constants. Together, this should cover
the kernel's `VTABLE` use case. In fact, the implementation [14] in
upstream Rust added a test case for it [15].
Rust 1.78.0 with debug assertions enabled (i.e. `-Cdebug-assertions=y`,
kernel's `CONFIG_RUST_DEBUG_ASSERTIONS=y`) now always checks all unsafe
preconditions, though without a way to opt-out for particular cases [16].
It would be ideal to have a way to selectively disable certain checks
per-call site for this one (i.e. not just per check but for particular
instances of a check), even if the vast majority of the checks remain
in place [17].
Rust 1.78.0 also improved a couple issues we reported when giving feedback
for the new `--check-cfg` feature [18] [19].
# `alloc` upgrade and reviewing
As mentioned above, compiler upgrades will not update `alloc` anymore,
since we dropped our `alloc` fork [3].
Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1780-2024-05-02 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://lore.kernel.org/rust-for-linux/20240328013603.206764-1-wedsonaf@gmail.com/ [3]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [4]
Link: https://github.com/rust-lang/rust/pull/120062 [5]
Link: https://github.com/rust-lang/rust/pull/120055 [6]
Link: https://reviews.llvm.org/D86310 [7]
Link: https://github.com/rust-lang/rust/pull/117772 [8]
Link: https://github.com/rust-lang/rust-clippy/pull/10903 [9]
Link: https://github.com/rust-lang/rust/pull/119365 [10]
Link: https://github.com/rust-lang/rust/issues/119364 [11]
Link: https://lore.kernel.org/rust-for-linux/ZWipTZysC2YL7qsq@Boquns-Mac-mini.home/ [12]
Link: https://github.com/rust-lang/rust/issues/119618 [13]
Link: https://github.com/rust-lang/rust/pull/120932 [14]
Link: https://github.com/rust-lang/rust/pull/120932/files#diff-e6fc1622c46054cd46b1d225c5386c5554564b3b0fa8a03c2dc2d8627a1079d9 [15]
Link: https://github.com/rust-lang/rust/issues/120969 [16]
Link: https://github.com/Rust-for-Linux/linux/issues/354 [17]
Link: https://github.com/rust-lang/rust/pull/121202 [18]
Link: https://github.com/rust-lang/rust/pull/121237 [19]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240401212303.537355-4-ojeda@kernel.org
[ Added a few more details and links I mentioned in the list. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is the next upgrade to the Rust toolchain, from 1.76.0 to 1.77.1
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
The `offset_of` feature (single-field `offset_of!`) that we were using
got stabilized in Rust 1.77.0 [3].
Therefore, now the only unstable features allowed to be used outside the
`kernel` crate is `new_uninit`, though other code to be upstreamed may
increase the list.
Please see [4] for details.
# Required changes
Rust 1.77.0 merged the `unused_tuple_struct_fields` lint into `dead_code`,
thus upgrading it from `allow` to `warn` [5]. In turn, this made `rustc`
complain about the `ThisModule`'s pointer field being never read, but
the previous patch adds the `as_ptr` method to it, needed by Binder [6],
so that we do not need to locally `allow` it.
# Other changes
Rust 1.77.0 introduces the `--check-cfg` feature [7], for which there
is a Call for Testing going on [8]. We were requested to test it and
we found it useful [9] -- we will likely enable it in the future.
# `alloc` upgrade and reviewing
The vast majority of changes 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://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1770-2024-03-21 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/rust-lang/rust/pull/118799 [3]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [4]
Link: https://github.com/rust-lang/rust/pull/118297 [5]
Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-2-08ba9197f637@google.com/#Z31rust:kernel:lib.rs [6]
Link: https://doc.rust-lang.org/nightly/unstable-book/compiler-flags/check-cfg.html [7]
Link: https://github.com/rust-lang/rfcs/pull/3013#issuecomment-1936648479 [8]
Link: https://github.com/rust-lang/rust/issues/82450#issuecomment-1947462977 [9]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240217002717.57507-1-ojeda@kernel.org
[ Upgraded to 1.77.1. Removed `allow(dead_code)` thanks to the previous
patch. Reworded accordingly. No changes to `alloc` during the beta. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
heap optimizations".
- Kuan-Wei Chiu has also sped up the library sorting code in the series
"lib/sort: Optimize the number of swaps and comparisons".
- Alexey Gladkov has added the ability for code running within an IPC
namespace to alter its IPC and MQ limits. The series is "Allow to
change ipc/mq sysctls inside ipc namespace".
- Geert Uytterhoeven has contributed some dhrystone maintenance work in
the series "lib: dhry: miscellaneous cleanups".
- Ryusuke Konishi continues nilfs2 maintenance work in the series
"nilfs2: eliminate kmap and kmap_atomic calls"
"nilfs2: fix kernel bug at submit_bh_wbc()"
- Nathan Chancellor has updated our build tools requirements in the
series "Bump the minimum supported version of LLVM to 13.0.1".
- Muhammad Usama Anjum continues with the selftests maintenance work in
the series "selftests/mm: Improve run_vmtests.sh".
- Oleg Nesterov has done some maintenance work against the signal code
in the series "get_signal: minor cleanups and fix".
Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.
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Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
- Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
heap optimizations".
- Kuan-Wei Chiu has also sped up the library sorting code in the series
"lib/sort: Optimize the number of swaps and comparisons".
- Alexey Gladkov has added the ability for code running within an IPC
namespace to alter its IPC and MQ limits. The series is "Allow to
change ipc/mq sysctls inside ipc namespace".
- Geert Uytterhoeven has contributed some dhrystone maintenance work in
the series "lib: dhry: miscellaneous cleanups".
- Ryusuke Konishi continues nilfs2 maintenance work in the series
"nilfs2: eliminate kmap and kmap_atomic calls"
"nilfs2: fix kernel bug at submit_bh_wbc()"
- Nathan Chancellor has updated our build tools requirements in the
series "Bump the minimum supported version of LLVM to 13.0.1".
- Muhammad Usama Anjum continues with the selftests maintenance work in
the series "selftests/mm: Improve run_vmtests.sh".
- Oleg Nesterov has done some maintenance work against the signal code
in the series "get_signal: minor cleanups and fix".
Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.
* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
nilfs2: prevent kernel bug at submit_bh_wbc()
nilfs2: fix failure to detect DAT corruption in btree and direct mappings
ocfs2: enable ocfs2_listxattr for special files
ocfs2: remove SLAB_MEM_SPREAD flag usage
assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
buildid: use kmap_local_page()
watchdog/core: remove sysctl handlers from public header
nilfs2: use div64_ul() instead of do_div()
mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
kexec: copy only happens before uchunk goes to zero
get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
get_signal: don't abuse ksig->info.si_signo and ksig->sig
const_structs.checkpatch: add device_type
Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>"
dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
list: leverage list_is_head() for list_entry_is_head()
nilfs2: MAINTAINERS: drop unreachable project mirror site
smp: make __smp_processor_id() 0-argument macro
fat: fix uninitialized field in nostale filehandles
...
This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
No unstable features that we use were stabilized in Rust 1.76.0.
The only unstable features allowed to be used outside the `kernel` crate
are still `new_uninit,offset_of`, though other code to be upstreamed
may increase the list.
Please see [3] for details.
# Required changes
`rustc` (and others) now warns when it cannot connect to the Make
jobserver, thus mark those invocations as recursive as needed. Please
see the previous commit for details.
# Other changes
Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore
for DWARFv4 [4][5]. For instance, in the uncompressed debug info case,
this debug information took:
samples/rust/rust_minimal.o ~64 KiB (~18% of total object size)
rust/kernel.o ~92 KiB (~15%)
rust/core.o ~114 KiB ( ~5%)
In the compressed debug info (zlib) case:
samples/rust/rust_minimal.o ~11 KiB (~6%)
rust/kernel.o ~17 KiB (~5%)
rust/core.o ~21 KiB (~1.5%)
In addition, the `rustc_codegen_gcc` backend now does not emit the
`.eh_frame` section when compiling under `-Cpanic=abort` [6], thus
removing the need for the patch in the CI to compile the kernel [7].
Moreover, it also now emits the `.comment` section too [6].
# `alloc` upgrade and reviewing
The vast majority of changes 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://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [3]
Link: https://github.com/rust-lang/compiler-team/issues/688 [4]
Link: https://github.com/rust-lang/rust/pull/117962 [5]
Link: https://github.com/rust-lang/rust/pull/118068 [6]
Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7]
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Patch series "Bump the minimum supported version of LLVM to 13.0.1".
This series bumps the minimum supported version of LLVM for building the
kernel to 13.0.1. The first patch does the bump and all subsequent
patches clean up all the various workarounds and checks for earlier
versions.
Quoting the first patch's commit message for those that were only on CC
for the clean ups:
When __builtin_mul_overflow() has arguments that differ in terms of
signedness and width, LLVM may generate a libcall to __muloti4 because
it performs the checks in terms of 65-bit multiplication. This issue
becomes harder to hit (but still possible) after LLVM 12.0.0, which
includes a special case for matching widths but different signs.
To gain access to this special case, which the kernel can take advantage
of when calls to __muloti4 appear, bump the minimum supported version of
LLVM for building the kernel to 13.0.1. 13.0.1 was chosen because there
is minimal impact to distribution support while allowing a few more
workarounds to be dropped in the kernel source than if 12.0.0 were
chosen. Looking at container images of up to date distribution versions:
archlinux:latest clang version 16.0.6
debian:oldoldstable-slim clang version 7.0.1-8+deb10u2 (tags/RELEASE_701/final)
debian:oldstable-slim Debian clang version 11.0.1-2
debian:stable-slim Debian clang version 14.0.6
debian:testing-slim Debian clang version 16.0.6 (19)
debian:unstable-slim Debian clang version 16.0.6 (19)
fedora:38 clang version 16.0.6 (Fedora 16.0.6-3.fc38)
fedora:latest clang version 17.0.6 (Fedora 17.0.6-1.fc39)
fedora:rawhide clang version 17.0.6 (Fedora 17.0.6-1.fc40)
opensuse/leap:latest clang version 15.0.7
opensuse/tumbleweed:latest clang version 17.0.6
ubuntu:focal clang version 10.0.0-4ubuntu1
ubuntu:latest Ubuntu clang version 14.0.0-1ubuntu1.1
ubuntu:rolling Ubuntu clang version 16.0.6 (15)
ubuntu:devel Ubuntu clang version 17.0.6 (3)
The only distribution that gets left behind is Debian Bullseye, as the
default version is 11.0.1; other distributions either have a newer
version than 13.0.1 or one older than the current minimum of 11.0.0.
Debian has easy access to more recent LLVM versions through
apt.llvm.org, so this is not as much of a concern. There are also the
kernel.org LLVM toolchains, which should work with distributions with
glibc 2.28 and newer.
Another benefit of slimming up the number of supported versions of LLVM
for building the kernel is reducing the build capacity needed to support
a matrix that builds with each supported version, which allows a matrix
to reallocate the freed up build capacity towards something else, such
as more configuration combinations.
This passes my build matrix with all supported versions.
This is based on Andrew's mm-nonmm-unstable to avoid trivial conflicts
with my series to update the LLVM links across the repository [1] but I
can easily rebase it to linux-kbuild if Masahiro would rather these
patches go through there (and defer the conflict resolution to the merge
window).
[1]: https://lore.kernel.org/20240109-update-llvm-links-v1-0-eb09b59db071@kernel.org/
This patch (of 11):
When __builtin_mul_overflow() has arguments that differ in terms of
signedness and width, LLVM may generate a libcall to __muloti4 because it
performs the checks in terms of 65-bit multiplication. This issue becomes
harder to hit (but still possible) after LLVM 12.0.0, which includes a
special case for matching widths but different signs.
To gain access to this special case, which the kernel can take advantage
of when calls to __muloti4 appear, bump the minimum supported version of
LLVM for building the kernel to 13.0.1. 13.0.1 was chosen because there
is minimal impact to distribution support while allowing a few more
workarounds to be dropped in the kernel source than if 12.0.0 were chosen.
Looking at container images of up to date distribution versions:
archlinux:latest clang version 16.0.6
debian:oldoldstable-slim clang version 7.0.1-8+deb10u2 (tags/RELEASE_701/final)
debian:oldstable-slim Debian clang version 11.0.1-2
debian:stable-slim Debian clang version 14.0.6
debian:testing-slim Debian clang version 16.0.6 (19)
debian:unstable-slim Debian clang version 16.0.6 (19)
fedora:38 clang version 16.0.6 (Fedora 16.0.6-3.fc38)
fedora:latest clang version 17.0.6 (Fedora 17.0.6-1.fc39)
fedora:rawhide clang version 17.0.6 (Fedora 17.0.6-1.fc40)
opensuse/leap:latest clang version 15.0.7
opensuse/tumbleweed:latest clang version 17.0.6
ubuntu:focal clang version 10.0.0-4ubuntu1
ubuntu:latest Ubuntu clang version 14.0.0-1ubuntu1.1
ubuntu:rolling Ubuntu clang version 16.0.6 (15)
ubuntu:devel Ubuntu clang version 17.0.6 (3)
The only distribution that gets left behind is Debian Bullseye, as the
default version is 11.0.1; other distributions either have a newer version
than 13.0.1 or one older than the current minimum of 11.0.0. Debian has
easy access to more recent LLVM versions through apt.llvm.org, so this is
not as much of a concern. There are also the kernel.org LLVM toolchains,
which should work with distributions with glibc 2.28 and newer.
Another benefit of slimming up the number of supported versions of LLVM
for building the kernel is reducing the build capacity needed to support a
matrix that builds with each supported version, which allows a matrix to
reallocate the freed up build capacity towards something else, such as
more configuration combinations.
Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-0-f5ff9bda41c5@kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1975
Link: https://github.com/llvm/llvm-project/issues/38013
Link: 3203143f13
Link: https://mirrors.edge.kernel.org/pub/tools/llvm/
Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-1-f5ff9bda41c5@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Conor Dooley <conor@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This is the next upgrade to the Rust toolchain, from 1.74.1 to 1.75.0
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
The `const_maybe_uninit_zeroed` unstable feature [3] was stabilized in
Rust 1.75.0, which we were using in the PHYLIB abstractions.
The only unstable features allowed to be used outside the `kernel` crate
are still `new_uninit,offset_of`, though other code to be upstreamed
may increase the list.
Please see [4] for details.
# Other improvements
Rust 1.75.0 stabilized `pointer_byte_offsets` [5] which we could
potentially use as an alternative for `ptr_metadata` in the future.
# Required changes
For this upgrade, no changes were required (i.e. on our side).
# `alloc` upgrade and reviewing
The vast majority of changes 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://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1750-2023-12-28 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/rust-lang/rust/issues/91850 [3]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [4]
Link: https://github.com/rust-lang/rust/issues/96283 [5]
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20231224172128.271447-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
1, Raise minimum clang version to 18.0.0;
2, Enable initial Rust support for LoongArch;
3, Add built-in dtb support for LoongArch;
4, Use generic interface to support crashkernel=X,[high,low];
5, Some bug fixes and other small changes;
6, Update the default config file.
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Merge tag 'loongarch-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch updates from Huacai Chen:
- Raise minimum clang version to 18.0.0
- Enable initial Rust support for LoongArch
- Add built-in dtb support for LoongArch
- Use generic interface to support crashkernel=X,[high,low]
- Some bug fixes and other small changes
- Update the default config file.
* tag 'loongarch-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (22 commits)
MAINTAINERS: Add BPF JIT for LOONGARCH entry
LoongArch: Update Loongson-3 default config file
LoongArch: BPF: Prevent out-of-bounds memory access
LoongArch: BPF: Support 64-bit pointers to kfuncs
LoongArch: Fix definition of ftrace_regs_set_instruction_pointer()
LoongArch: Use generic interface to support crashkernel=X,[high,low]
LoongArch: Fix and simplify fcsr initialization on execve()
LoongArch: Let cores_io_master cover the largest NR_CPUS
LoongArch: Change SHMLBA from SZ_64K to PAGE_SIZE
LoongArch: Add a missing call to efi_esrt_init()
LoongArch: Parsing CPU-related information from DTS
LoongArch: dts: DeviceTree for Loongson-2K2000
LoongArch: dts: DeviceTree for Loongson-2K1000
LoongArch: dts: DeviceTree for Loongson-2K0500
LoongArch: Allow device trees be built into the kernel
dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for interrupt-names
dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for reg-names
dt-bindings: loongarch: Add Loongson SoC boards compatibles
dt-bindings: loongarch: Add CPU bindings for LoongArch
LoongArch: Enable initial Rust support
...
The existing mainline clang development version encounters difficulties
compiling the LoongArch kernel module. It is anticipated that this issue
will be resolved in the upcoming 18.0.0 release. To prevent user
confusion arising from broken builds, it is advisable to raise the
minimum required clang version for LoongArch to 18.0.0.
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1941
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
This is the next upgrade to the Rust toolchain, from 1.73.0 to 1.74.1
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
No unstable features (that we use) were stabilized.
Therefore, the only unstable features allowed to be used outside the
`kernel` crate are still `new_uninit,offset_of`, though other code to
be upstreamed may increase the list (e.g. `offset_of` was added recently).
Please see [3] for details.
# Other improvements
Rust 1.74.0 allows to use `#[repr(Rust)]` explicitly [4], which can be
useful to be explicit about particular cases that would normally use
e.g. the C representation, such as silencing lints like the upcoming
additions we requested [5] to the `no_mangle_with_rust_abi` Clippy lint
(which in turn triggered the `#[repr(Rust)]` addition).
Rust 1.74.0 includes a fix for one of the false negative cases we reported
in Clippy's `disallowed_macros` lint [6] that we would like to use in
the future.
Rust 1.74.1 fixes an ICE that the Apple AGX GPU driver was hitting [7].
# Required changes
For this upgrade, no changes were required (i.e. on our side).
# `alloc` upgrade and reviewing
The vast majority of changes 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://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1741-2023-12-07 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [3]
Link: https://github.com/rust-lang/rust/pull/114201 [4]
Link: https://github.com/rust-lang/rust-clippy/issues/11219 [5]
Link: https://github.com/rust-lang/rust-clippy/issues/11431 [6]
Link: https://github.com/rust-lang/rust/issues/117976#issuecomment-1822225691 [7]
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/r/20231214092958.377061-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is the next upgrade to the Rust toolchain, from 1.72.1 to 1.73.0
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
No unstable features (that we use) were stabilized.
Therefore, the only unstable feature allowed to be used outside
the `kernel` crate is still `new_uninit`, though other code to be
upstreamed may increase the list.
Please see [3] for details.
# Required changes
For the upgrade, the following changes are required:
- Allow `internal_features` for `feature(compiler_builtins)` since
now Rust warns about using internal compiler and standard library
features (similar to how it also warns about incomplete ones) [4].
- A cleanup for a documentation link thanks to a new `rustdoc` lint.
See previous commits for details.
- A need to make an intra-doc link to a macro explicit, due to a
change in behavior in `rustdoc`. See previous commits for details.
# `alloc` upgrade and reviewing
The vast majority of changes 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://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1730-2023-10-05 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [3]
Link: https://github.com/rust-lang/compiler-team/issues/596 [4]
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20231005210556.466856-4-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is the third upgrade to the Rust toolchain, from 1.71.1 to 1.72.1
(i.e. the latest) [1].
See the upgrade policy [2] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
No unstable features (that we use) were stabilized.
Therefore, the only unstable feature allowed to be used outside
the `kernel` crate is still `new_uninit`, though other code to be
upstreamed may increase the list.
Please see [3] for details.
# Other improvements
Previously, the compiler could incorrectly generate a `.eh_frame`
section under `-Cpanic=abort`. We were hitting this bug when debug
assertions were enabled (`CONFIG_RUST_DEBUG_ASSERTIONS=y`) [4]:
LD .tmp_vmlinux.kallsyms1
ld.lld: error: <internal>:(.eh_frame) is being placed in '.eh_frame'
Gary fixed the issue in Rust 1.72.0 [5].
# Required changes
For the upgrade, the following changes are required:
- A call to `Box::from_raw` in `rust/kernel/sync/arc.rs` now requires
an explicit `drop()` call. See previous patch for details.
# `alloc` upgrade and reviewing
The vast majority of changes 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://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1721-2023-09-19 [1]
Link: https://rust-for-linux.com/rust-version-policy [2]
Link: https://github.com/Rust-for-Linux/linux/issues/2 [3]
Closes: https://github.com/Rust-for-Linux/linux/issues/1012 [4]
Link: https://github.com/rust-lang/rust/pull/112403 [5]
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Link: https://lore.kernel.org/r/20230823160244.188033-3-ojeda@kernel.org
[ Used 1.72.1 instead of .0 (no changes in `alloc`) and reworded
to mention that we hit the `.eh_frame` bug under debug assertions. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In LLVM 16, anonymous items may return names like `(unnamed union at ..)`
rather than empty names [1], which breaks Rust-enabled builds because
bindgen assumed an empty name instead of detecting them via
`clang_Cursor_isAnonymous` [2]:
$ make rustdoc LLVM=1 CLIPPY=1 -j$(nproc)
RUSTC L rust/core.o
BINDGEN rust/bindings/bindings_generated.rs
BINDGEN rust/bindings/bindings_helpers_generated.rs
BINDGEN rust/uapi/uapi_generated.rs
thread 'main' panicked at '"ftrace_branch_data_union_(anonymous_at__/_/include/linux/compiler_types_h_146_2)" is not a valid Ident', .../proc-macro2-1.0.24/src/fallback.rs:693:9
...
thread 'main' panicked at '"ftrace_branch_data_union_(anonymous_at__/_/include/linux/compiler_types_h_146_2)" is not a valid Ident', .../proc-macro2-1.0.24/src/fallback.rs:693:9
...
This was fixed in bindgen 0.62.0. Therefore, upgrade bindgen to
a more recent version, 0.65.1, to support LLVM 16.
Since bindgen 0.58.0 changed the `--{white,black}list-*` flags to
`--{allow,block}list-*` [3], update them on our side too.
In addition, bindgen 0.61.0 moved its CLI utility into a binary crate
called `bindgen-cli` [4]. Thus update the installation command in the
Quick Start guide.
Moreover, bindgen 0.61.0 changed the default functionality to bind
`size_t` to `usize` [5] and added the `--no-size_t-is-usize` flag
to not bind `size_t` as `usize`. Then bindgen 0.65.0 removed
the `--size_t-is-usize` flag [6]. Thus stop passing the flag to bindgen.
Finally, bindgen 0.61.0 added support for the `noreturn` attribute (in
its different forms) [7]. Thus remove the infinite loop in our Rust
panic handler after calling `BUG()`, since bindgen now correctly
generates a `BUG()` binding that returns `!` instead of `()`.
Link: 19e984ef8f [1]
Link: https://github.com/rust-lang/rust-bindgen/pull/2319 [2]
Link: https://github.com/rust-lang/rust-bindgen/pull/1990 [3]
Link: https://github.com/rust-lang/rust-bindgen/pull/2284 [4]
Link: cc78b6fdb6 [5]
Link: https://github.com/rust-lang/rust-bindgen/pull/2408 [6]
Link: https://github.com/rust-lang/rust-bindgen/issues/2094 [7]
Signed-off-by: Aakash Sen Sharma <aakashsensharma@gmail.com>
Closes: https://github.com/Rust-for-Linux/linux/issues/1013
Tested-by: Ariel Miculas <amiculas@cisco.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20230612194311.24826-1-aakashsensharma@gmail.com
[ Reworded commit message. Mentioned the `bindgen-cli` binary crate
change, linked to it and updated the Quick Start guide. Re-added a
deleted "as" word in a code comment and reflowed comment to respect
the maximum length. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This is the second upgrade to the Rust toolchain, from 1.68.2 to 1.71.1
(i.e. the latest).
See the upgrade policy [1] and the comments on the first upgrade in
commit 3ed03f4da0 ("rust: upgrade to Rust 1.68.2").
# Unstable features
No unstable features (that we use) were stabilized.
Therefore, the only unstable feature allowed to be used outside
the `kernel` crate is still `new_uninit`, though other code to be
upstreamed may increase the list.
Please see [2] for details.
# Required changes
For the upgrade, this patch requires the following changes:
- Removal of the `__rust_*` allocator functions, together with
the addition of the `__rust_no_alloc_shim_is_unstable` static.
See [3] for details.
- Some more compiler builtins added due to `<f{32,64}>::midpoint()`
that got added in Rust 1.71 [4].
# `alloc` upgrade and reviewing
The vast majority of changes 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://github.com/rust-lang/rust/pull/86844 [3]
Link: https://github.com/rust-lang/rust/pull/92048 [4]
Closes: https://github.com/Rust-for-Linux/linux/issues/68
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Link: https://lore.kernel.org/r/20230729220317.416771-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Raise the minimum gcc version for parisc64 to 12.0.0 (for __int128 type)
and keep 5.1.0 as minimum for 32-bit parisc target.
Fixes: 8664645ade ("parisc: Raise minimal GCC version")
Signed-off-by: Helge Deller <deller@gmx.de>
- Introduce cmpxchg128() -- aka. the demise of cmpxchg_double().
The cmpxchg128() family of functions is basically & functionally
the same as cmpxchg_double(), but with a saner interface: instead
of a 6-parameter horror that forced u128 - u64/u64-halves layout
details on the interface and exposed users to complexity,
fragility & bugs, use a natural 3-parameter interface with u128 types.
- Restructure the generated atomic headers, and add
kerneldoc comments for all of the generic atomic{,64,_long}_t
operations. Generated definitions are much cleaner now,
and come with documentation.
- Implement lock_set_cmp_fn() on lockdep, for defining an ordering
when taking multiple locks of the same type. This gets rid of
one use of lockdep_set_novalidate_class() in the bcache code.
- Fix raw_cpu_generic_try_cmpxchg() bug due to an unintended
variable shadowing generating garbage code on Clang on certain
ARM builds.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
- Introduce cmpxchg128() -- aka. the demise of cmpxchg_double()
The cmpxchg128() family of functions is basically & functionally the
same as cmpxchg_double(), but with a saner interface.
Instead of a 6-parameter horror that forced u128 - u64/u64-halves
layout details on the interface and exposed users to complexity,
fragility & bugs, use a natural 3-parameter interface with u128
types.
- Restructure the generated atomic headers, and add kerneldoc comments
for all of the generic atomic{,64,_long}_t operations.
The generated definitions are much cleaner now, and come with
documentation.
- Implement lock_set_cmp_fn() on lockdep, for defining an ordering when
taking multiple locks of the same type.
This gets rid of one use of lockdep_set_novalidate_class() in the
bcache code.
- Fix raw_cpu_generic_try_cmpxchg() bug due to an unintended variable
shadowing generating garbage code on Clang on certain ARM builds.
* tag 'locking-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
locking/atomic: scripts: fix ${atomic}_dec_if_positive() kerneldoc
percpu: Fix self-assignment of __old in raw_cpu_generic_try_cmpxchg()
locking/atomic: treewide: delete arch_atomic_*() kerneldoc
locking/atomic: docs: Add atomic operations to the driver basic API documentation
locking/atomic: scripts: generate kerneldoc comments
docs: scripts: kernel-doc: accept bitwise negation like ~@var
locking/atomic: scripts: simplify raw_atomic*() definitions
locking/atomic: scripts: simplify raw_atomic_long*() definitions
locking/atomic: scripts: split pfx/name/sfx/order
locking/atomic: scripts: restructure fallback ifdeffery
locking/atomic: scripts: build raw_atomic_long*() directly
locking/atomic: treewide: use raw_atomic*_<op>()
locking/atomic: scripts: add trivial raw_atomic*_<op>()
locking/atomic: scripts: factor out order template generation
locking/atomic: scripts: remove leftover "${mult}"
locking/atomic: scripts: remove bogus order parameter
locking/atomic: xtensa: add preprocessor symbols
locking/atomic: x86: add preprocessor symbols
locking/atomic: sparc: add preprocessor symbols
locking/atomic: sh: add preprocessor symbols
...
64-bit targets need the __int128 type, which for pa-risc means raising
the minimum gcc version to 11.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Helge Deller <deller@gmx.de>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20230602143912.GI620383%40hirez.programming.kicks-ass.net
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>
include/linux/compiler-intel.h had no update in the past 3 years.
We often forget about the third C compiler to build the kernel.
For example, commit a0a12c3ed0 ("asm goto: eradicate CC_HAS_ASM_GOTO")
only mentioned GCC and Clang.
init/Kconfig defines CC_IS_GCC and CC_IS_CLANG but not CC_IS_ICC,
and nobody has reported any issue.
I guess the Intel Compiler support is broken, and nobody is caring
about it.
Harald Arnesen pointed out ICC (classic Intel C/C++ compiler) is
deprecated:
$ icc -v
icc: remark #10441: The Intel(R) C++ Compiler Classic (ICC) is
deprecated and will be removed from product release in the second half
of 2023. The Intel(R) oneAPI DPC++/C++ Compiler (ICX) is the recommended
compiler moving forward. Please transition to use this compiler. Use
'-diag-disable=10441' to disable this message.
icc version 2021.7.0 (gcc version 12.1.0 compatibility)
Arnd Bergmann provided a link to the article, "Intel C/C++ compilers
complete adoption of LLVM".
lib/zstd/common/compiler.h and lib/zstd/compress/zstd_fast.c were kept
untouched for better sync with https://github.com/facebook/zstd
Link: https://www.intel.com/content/www/us/en/developer/articles/technical/adoption-of-llvm-complete-icx.html
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Binutils 2.23 was released in 2012. Almost 10 years old.
We already require GCC 5.1, released in 2015.
Bump the binutils version to 2.25, which was released some months
before GCC 5.1.
With this applied, some subsystems can start to clean up code.
Examples:
arch/arm/Kconfig.assembler
arch/mips/vdso/Kconfig
arch/powerpc/Makefile
arch/x86/Kconfig.assembler
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Before version 15.0.0 llvm's integrated assembler may silently
generate corrupted code on s390. See e.g. commit e9953b729b
("s390/boot: workaround llvm IAS bug") for further details.
While there have been workarounds applied for all known existing
locations, there is nothing that prevents that new code with
problematic patterns will be added.
Therefore raise the minimum clang version to 15.0.0. Note that llvm
commit e547b04d5b2c ("[SystemZ] Bugfix for symbolic displacements."),
which is included in 15.0.0, fixes the broken code generation.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20221031123456.3872220-1-hca@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
This script tests whether the Rust toolchain requirements are in place
to enable Rust support. It uses `min-tool-version.sh` to fetch
the version numbers.
The build system will call it to set `CONFIG_RUST_IS_AVAILABLE` in
a later patch.
It also has an option (`-v`) to explain what is missing, which is
useful to set up the development environment. This is used via
the `make rustavailable` target added in a later patch.
Reviewed-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Finn Behrens <me@kloenk.de>
Signed-off-by: Finn Behrens <me@kloenk.de>
Co-developed-by: Miguel Cano <macanroj@gmail.com>
Signed-off-by: Miguel Cano <macanroj@gmail.com>
Co-developed-by: Tiago Lam <tiagolam@gmail.com>
Signed-off-by: Tiago Lam <tiagolam@gmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Before version 14.0.0 llvm's integrated assembler fails to handle some
displacement variants:
arch/s390/purgatory/head.S:108:10: error: invalid operand for instruction
lg %r11,kernel_type-.base_crash(%r13)
Instead of working around this and given that this is already fixed
raise the minimum clang version from 13.0.0 to 14.0.0.
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://reviews.llvm.org/D113341
Link: https://lore.kernel.org/r/20220511120532.2228616-9-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
LLVM versions prior to 11.0.0 have a harder time with dead code
elimination, which can cause issues with commonly used expressions such
as BUILD_BUG_ON and the bitmask functions/macros in bitfield.h (see the
first two issues links below).
Whenever there is an issue within LLVM that has been resolved in a later
release, the only course of action is to gate the problematic
configuration or source code on the toolchain verson or raise the
minimum supported version of LLVM for building the kernel, as LLVM has a
limited support lifetime compared to GCC. GCC major releases will
typically see a few point releases across a two year period on average
whereas LLVM major releases are only supported until the next major
release and will only see one or two point releases within that
timeframe. For example, GCC 8.1 was released in May 2018 and GCC 8.5 was
released in May 2021, whereas LLVM 12.0.0 was released in April 2021 and
its only point release, 12.0.1, was released in July 2021, giving a
minimal window for fixes to be backported.
To resolve these build errors around improper dead code elimination,
raise the minimum supported version of LLVM for building the kernel to
11.0.0. Doing so is a more proper solution than mucking around with core
kernel macros that have always worked with GCC or disabling drivers for
using these macros in a proper manner. This type of issue may continue
to crop up and require patching, which creates more debt for bumping the
minimum supported version in the future.
This should have a minimal impact to distributions. Using a script to
pull several different Docker images and check the output of
'clang --version':
archlinux:latest: clang version 13.0.0
debian:oldoldstable-slim: clang version 3.8.1-24 (tags/RELEASE_381/final)
debian:oldstable-slim: clang version 7.0.1-8+deb10u2 (tags/RELEASE_701/final)
debian:stable-slim: Debian clang version 11.0.1-2
debian:testing-slim: Debian clang version 11.1.0-4
debian:unstable-slim: Debian clang version 11.1.0-4
fedora:34: clang version 12.0.1 (Fedora 12.0.1-1.fc34)
fedora:latest: clang version 13.0.0 (Fedora 13.0.0-3.fc35)
fedora:rawhide: clang version 13.0.0 (Fedora 13.0.0-5.fc36)
opensuse/leap:15.2: clang version 9.0.1
opensuse/leap:latest: clang version 11.0.1
opensuse/tumbleweed:latest: clang version 13.0.0
ubuntu:bionic: clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final)
ubuntu:latest: clang version 10.0.0-4ubuntu1
ubuntu:hirsute: Ubuntu clang version 12.0.0-3ubuntu1~21.04.2
ubuntu:rolling: Ubuntu clang version 13.0.0-2
ubuntu:devel: Ubuntu clang version 13.0.0-9
In every case, the distribution's version of clang is either older than
the current minimum supported version of LLVM 10.0.1 or equal to or
greater than the proposed 11.0.0 so nothing should change.
Another benefit of this change is LLVM=1 works better with arm64 and
x86_64 since commit f12b034afe ("scripts/Makefile.clang: default to
LLVM_IAS=1") enabled the integrated assembler by default, which only
works well with clang 11+ (clang-10 required it to be disabled to
successfully build a kernel).
Link: https://github.com/ClangBuiltLinux/linux/issues/1293
Link: https://github.com/ClangBuiltLinux/linux/issues/1506
Link: https://github.com/ClangBuiltLinux/linux/issues/1511
Link: fa496ce3c6
Link: https://groups.google.com/g/clang-built-linux/c/mPQb9_ZWW0s/m/W7o6S-QTBAAJ
Link: https://github.com/ClangBuiltLinux/misc-scripts
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
commit fad7cd3310 ("nbd: add the check to prevent overflow in
__nbd_ioctl()") raised an issue from the fallback helpers added in
commit f0907827a8 ("compiler.h: enable builtin overflow checkers and
add fallback code")
Specifically, the helpers for checking whether the results of a
multiplication overflowed (__unsigned_mul_overflow,
__signed_add_overflow) use the division operator when
!COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW. This is problematic for 64b
operands on 32b hosts.
Also, because the macro is type agnostic, it is very difficult to write
a similarly type generic macro that dispatches to one of:
* div64_s64
* div64_u64
* div_s64
* div_u64
Raising the minimum supported versions allows us to remove all of the
fallback helpers for !COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW, instead
dispatching the compiler builtins.
arm64 has already raised the minimum supported GCC version to 5.1, do
this for all targets now. See the link below for the previous
discussion.
Link: https://lore.kernel.org/all/20210909182525.372ee687@canb.auug.org.au/
Link: https://lore.kernel.org/lkml/CAK7LNASs6dvU6D3jL2GG3jW58fXfaj6VNOe55NJnTB8UPuk2pA@mail.gmail.com/
Link: https://github.com/ClangBuiltLinux/linux/issues/1438
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
clang versions prior to the current development version of 13.0.0 cannot
compile s390 after commit 3abbdfde5a65 ("s390/bitops: use register pair
instead of register asm") and the s390 maintainers do not intend to work
around this in the kernel. Codify this in scripts/min-tool-version.sh
similar to arm64 with GCC 5.1.0 so that there are no reports of broken
builds.
[hca@linux.ibm.com: breaking compatibility with older clang compilers
is intended to finally make use of a feature which allows the
compiler to allocate even/odd register pairs. This is possible since
a very long time with gcc, but only since llvm-project commit
d058262b1471 ("[SystemZ] Support i128 inline asm operands.") with
clang. Using that feature allows to get rid of error prone register
asm statements, of which the above named kernel commit is only the
first of a larger not yet complete series.]
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20210617193139.856957-1-nathan@kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The kernel build uses various tools, many of which are provided by the
same software suite, for example, LLVM and Binutils.
When you raise the minimum version of Clang/LLVM, you need to update
clang_min_version in scripts/cc-version.sh and also lld_min_version in
scripts/ld-version.sh.
Kbuild can handle CC=clang and LD=ld.lld independently, but it does not
make much sense to maintain their versions separately.
Let's create a central place of minimum tool versions so you do not need
to touch multiple files. scripts/min-tool-version.sh prints the minimum
version of the given tool.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Miguel Ojeda
Linus Torvalds
Nathan Chancellor
WANG Rui
Aakash Sen Sharma
Helge Deller
Peter Zijlstra
Masahiro Yamada
Heiko Carstens
Nick Desaulniers