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448 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Linus Torvalds
|
88b29f3f57 |
Modules changes for v7.1-rc1
Kernel symbol flags:
- Replace the separate *_gpl symbol sections (__ksymtab_gpl and
__kcrctab_gpl) with a unified symbol table and a new
__kflagstab section. This section stores symbol flags, such as
the GPL-only flag, as an 8-bit bitset for each exported symbol.
This is a cleanup that simplifies symbol lookup in the module
loader by avoiding table fragmentation and will allow a cleaner
way to add more flags later if needed.
Module signature UAPI:
- Move struct module_signature to the UAPI headers to allow reuse
by tools outside the kernel proper, such as kmod and
scripts/sign-file. This also renames a few constants for clarity
and drops unused signature types as preparation for hash-based
module integrity checking work that's in progress.
Sysfs:
- Add a /sys/module/<module>/import_ns sysfs attribute to show
the symbol namespaces imported by loaded modules. This makes it
easier to verify driver API access at runtime on systems that
care about such things (e.g. Android).
Cleanups and fixes:
- Force sh_addr to 0 for all sections in module.lds. This prevents
non-zero section addresses when linking modules with ld.bfd -r,
which confused elfutils.
- Fix a memory leak of charp module parameters on module unload
when the kernel is configured with CONFIG_SYSFS=n.
- Override the -EEXIST error code returned by module_init() to
userspace. This prevents confusion with the errno reserved by
the module loader to indicate that a module is already loaded.
- Simplify the warning message and drop the stack dump on positive
returns from module_init().
- Drop unnecessary extern keywords from function declarations and
synchronize parse_args() arguments with their implementation.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
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Merge tag 'modules-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux
Pull module updates from Sami Tolvanen:
"Kernel symbol flags:
- Replace the separate *_gpl symbol sections (__ksymtab_gpl and
__kcrctab_gpl) with a unified symbol table and a new __kflagstab
section.
This section stores symbol flags, such as the GPL-only flag, as an
8-bit bitset for each exported symbol. This is a cleanup that
simplifies symbol lookup in the module loader by avoiding table
fragmentation and will allow a cleaner way to add more flags later
if needed.
Module signature UAPI:
- Move struct module_signature to the UAPI headers to allow reuse by
tools outside the kernel proper, such as kmod and
scripts/sign-file.
This also renames a few constants for clarity and drops unused
signature types as preparation for hash-based module integrity
checking work that's in progress.
Sysfs:
- Add a /sys/module/<module>/import_ns sysfs attribute to show the
symbol namespaces imported by loaded modules.
This makes it easier to verify driver API access at runtime on
systems that care about such things (e.g. Android).
Cleanups and fixes:
- Force sh_addr to 0 for all sections in module.lds. This prevents
non-zero section addresses when linking modules with 'ld.bfd -r',
which confused elfutils.
- Fix a memory leak of charp module parameters on module unload when
the kernel is configured with CONFIG_SYSFS=n.
- Override the -EEXIST error code returned by module_init() to
userspace. This prevents confusion with the errno reserved by the
module loader to indicate that a module is already loaded.
- Simplify the warning message and drop the stack dump on positive
returns from module_init().
- Drop unnecessary extern keywords from function declarations and
synchronize parse_args() arguments with their implementation"
* tag 'modules-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: (23 commits)
module: Simplify warning on positive returns from module_init()
module: Override -EEXIST module return
documentation: remove references to *_gpl sections
module: remove *_gpl sections from vmlinux and modules
module: deprecate usage of *_gpl sections in module loader
module: use kflagstab instead of *_gpl sections
module: populate kflagstab in modpost
module: add kflagstab section to vmlinux and modules
module: define ksym_flags enumeration to represent kernel symbol flags
selftests/bpf: verify_pkcs7_sig: Use 'struct module_signature' from the UAPI headers
sign-file: use 'struct module_signature' from the UAPI headers
tools uapi headers: add linux/module_signature.h
module: Move 'struct module_signature' to UAPI
module: Give MODULE_SIG_STRING a more descriptive name
module: Give 'enum pkey_id_type' a more specific name
module: Drop unused signature types
extract-cert: drop unused definition of PKEY_ID_PKCS7
docs: symbol-namespaces: mention sysfs attribute
module: expose imported namespaces via sysfs
module: Remove extern keyword from param prototypes
...
|
||
|
Linus Torvalds
|
ef3da345cc |
vfs-7.1-rc1.misc
Please consider pulling these changes from the signed vfs-7.1-rc1.misc tag.
Thanks!
Christian
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Merge tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
"Features:
- coredump: add tracepoint for coredump events
- fs: hide file and bfile caches behind runtime const machinery
Fixes:
- fix architecture-specific compat_ftruncate64 implementations
- dcache: Limit the minimal number of bucket to two
- fs/omfs: reject s_sys_blocksize smaller than OMFS_DIR_START
- fs/mbcache: cancel shrink work before destroying the cache
- dcache: permit dynamic_dname()s up to NAME_MAX
Cleanups:
- remove or unexport unused fs_context infrastructure
- trivial ->setattr cleanups
- selftests/filesystems: Assume that TIOCGPTPEER is defined
- writeback: fix kernel-doc function name mismatch for wb_put_many()
- autofs: replace manual symlink buffer allocation in autofs_dir_symlink
- init/initramfs.c: trivial fix: FSM -> Finite-state machine
- fs: remove stale and duplicate forward declarations
- readdir: Introduce dirent_size()
- fs: Replace user_access_{begin/end} by scoped user access
- kernel: acct: fix duplicate word in comment
- fs: write a better comment in step_into() concerning .mnt assignment
- fs: attr: fix comment formatting and spelling issues"
* tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits)
dcache: permit dynamic_dname()s up to NAME_MAX
fs: attr: fix comment formatting and spelling issues
fs: hide file and bfile caches behind runtime const machinery
fs: write a better comment in step_into() concerning .mnt assignment
proc: rename proc_notify_change to proc_setattr
proc: rename proc_setattr to proc_nochmod_setattr
affs: rename affs_notify_change to affs_setattr
adfs: rename adfs_notify_change to adfs_setattr
hfs: update comments on hfs_inode_setattr
kernel: acct: fix duplicate word in comment
fs: Replace user_access_{begin/end} by scoped user access
readdir: Introduce dirent_size()
coredump: add tracepoint for coredump events
fs: remove do_sys_truncate
fs: pass on FTRUNCATE_* flags to do_truncate
fs: fix archiecture-specific compat_ftruncate64
fs: remove stale and duplicate forward declarations
init/initramfs.c: trivial fix: FSM -> Finite-state machine
autofs: replace manual symlink buffer allocation in autofs_dir_symlink
fs/mbcache: cancel shrink work before destroying the cache
...
|
||
|
Siddharth Nayyar
|
f18540256b |
module: remove *_gpl sections from vmlinux and modules
These sections are not used anymore and can be removed from vmlinux and modules during linking. Signed-off-by: Siddharth Nayyar <sidnayyar@google.com> Reviewed-by: Petr Pavlu <petr.pavlu@suse.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> |
||
|
Siddharth Nayyar
|
9743311b45 |
module: add kflagstab section to vmlinux and modules
This patch introduces a __kflagstab section to store symbol flags in a
dedicated data structure, similar to how CRCs are handled in the
__kcrctab.
The flags for a given symbol in __kflagstab will be located at the same
index as the symbol's entry in __ksymtab and its CRC in __kcrctab. This
design decouples the flags from the symbol table itself, allowing us to
maintain a single, sorted __ksymtab. As a result, the symbol search
remains an efficient, single lookup, regardless of the number of flags
we add in the future.
The motivation for this change comes from the Android kernel, which uses
an additional symbol flag to restrict the use of certain exported
symbols by unsigned modules, thereby enhancing kernel security. This
__kflagstab can be implemented as a bitmap to efficiently manage which
symbols are available for general use versus those restricted to signed
modules only.
This section will contain read-only data for values of kernel symbol
flags in the form of an 8-bit bitsets for each kernel symbol. Each bit
in the bitset represents a flag value defined by ksym_flags enumeration.
Petr Pavlu ran a small test to get a better understanding of the
different section sizes resulting from this patch series. He used
v6.17-rc6 together with the openSUSE x86_64 config [1], which is fairly
large. The resulting vmlinux.bin (no debuginfo) had an on-disk size of
58 MiB, and included 5937 + 6589 (GPL-only) exported symbols.
The following table summarizes his measurements and calculations
regarding the sizes of all sections related to exported symbols:
| HAVE_ARCH_PREL32_RELOCATIONS | !HAVE_ARCH_PREL32_RELOCATIONS
Section | Base [B] | Ext. [B] | Sep. [B] | Base [B] | Ext. [B] | Sep. [B]
----------------------------------------------------------------------------------------
__ksymtab | 71244 | 200416 | 150312 | 142488 | 400832 | 300624
__ksymtab_gpl | 79068 | NA | NA | 158136 | NA | NA
__kcrctab | 23748 | 50104 | 50104 | 23748 | 50104 | 50104
__kcrctab_gpl | 26356 | NA | NA | 26356 | NA | NA
__ksymtab_strings | 253628 | 253628 | 253628 | 253628 | 253628 | 253628
__kflagstab | NA | NA | 12526 | NA | NA | 12526
----------------------------------------------------------------------------------------
Total | 454044 | 504148 | 466570 | 604356 | 704564 | 616882
Increase to base [%] | NA | 11.0 | 2.8 | NA | 16.6 | 2.1
The column "HAVE_ARCH_PREL32_RELOCATIONS -> Base" contains the measured
numbers. The rest of the values are calculated. The "Ext." column
represents an alternative approach of extending __ksymtab to include a
bitset of symbol flags, and the "Sep." column represents the approach of
having a separate __kflagstab. With HAVE_ARCH_PREL32_RELOCATIONS, each
kernel_symbol is 12 B in size and is extended to 16 B. With
!HAVE_ARCH_PREL32_RELOCATIONS, it is 24 B, extended to 32 B. Note that
this does not include the metadata needed to relocate __ksymtab*, which
is freed after the initial processing.
Adding __kflagstab as a separate section has a negligible impact, as
expected. When extending __ksymtab (kernel_symbol) instead, the worst
case with !HAVE_ARCH_PREL32_RELOCATIONS increases the export data size
by 16.6%. Note that the larger increase in size for the latter approach
is due to 4-byte alignment of kernel_symbol data structure, instead of
1-byte alignment for the flags bitset in __kflagstab in the former
approach.
Based on the above, it was concluded that introducing __kflagstab makes
sense, as the added complexity is minimal over extending kernel_symbol,
and there is overall simplification of symbol finding logic in the
module loader.
Signed-off-by: Siddharth Nayyar <sidnayyar@google.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
[Sami: Updated commit message to include details from the cover letter.]
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
|
||
|
Mateusz Guzik
|
1f1651d6dc
|
fs: hide file and bfile caches behind runtime const machinery
s/cachep/cache/ for consistency with namei and dentry caches. Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://patch.msgid.link/20260328173728.3388070-1-mjguzik@gmail.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Nathan Chancellor
|
8678591b47
|
kbuild: Split .modinfo out from ELF_DETAILS
Commit |
||
|
Mateusz Guzik
|
7ca83f8ebe |
fs: hide names_cache behind runtime const machinery
s/names_cachep/names_cache/ for consistency with dentry cache. Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> |
||
|
Linus Torvalds
|
36492b7141 |
Detect unused tracepoints for v6.19:
If a tracepoint is defined but never used (TRACE_EVENT() created but no
trace_<tracepoint>() called), it can take up to or more than 5K of memory
each. This can add up as there are around a hundred unused tracepoints with
various configs. That is 500K of wasted memory.
Add a make build parameter of "UT=1" to have the build warn if an unused
tracepoint is detected in the build. This allows detection of unused
tracepoints to be upstream so that outreachy and the mentoring project can
have new developers look for fixing them, without having these warnings
suddenly show up when someone upgrades their kernel. When all known unused
tracepoints are removed, then the "UT=1" build parameter can be removed and
unused tracepoints will always warn. This will catch new unused tracepoints
after the current ones have been removed.
- Separate out elf functions from sorttable.c
Move out the ELF parsing functions from sorttable.c so that the tracing
tooling can use it.
- Add a tracepoint verifier tool to the build process
If "UT=1" is added to the kernel command line, any unused tracepoints will
trigger a warning at build time.
- Do not warn about unused tracepoints for tracepoints that are exported
There are sever cases where a tracepoint is created by the kernel and used
by modules. Since there's no easy way to detect if these are truly unused
since the users are in modules, if a tracepoint is exported, assume it
will eventually be used by a module. Note, there's not many exported
tracepoints so this should not be a problem to ignore them.
- Have building of modules also detect unused tracepoints
Do not only check the main vmlinux for unused tracepoints, also check
modules. If a module is defining a tracepoint it should be using it.
- Add the tracepoint-update program to the ignore file
The new tracepoint-update program needs to be ignored by git.
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Merge tag 'tracepoints-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull unused tracepoints update from Steven Rostedt:
"Detect unused tracepoints.
If a tracepoint is defined but never used (TRACE_EVENT() created but
no trace_<tracepoint>() called), it can take up to or more than 5K of
memory each. This can add up as there are around a hundred unused
tracepoints with various configs. That is 500K of wasted memory.
Add a make build parameter of "UT=1" to have the build warn if an
unused tracepoint is detected in the build. This allows detection of
unused tracepoints to be upstream so that outreachy and the mentoring
project can have new developers look for fixing them, without having
these warnings suddenly show up when someone upgrades their kernel.
When all known unused tracepoints are removed, then the "UT=1" build
parameter can be removed and unused tracepoints will always warn. This
will catch new unused tracepoints after the current ones have been
removed.
Summary:
- Separate out elf functions from sorttable.c
Move out the ELF parsing functions from sorttable.c so that the
tracing tooling can use it.
- Add a tracepoint verifier tool to the build process
If "UT=1" is added to the kernel command line, any unused
tracepoints will trigger a warning at build time.
- Do not warn about unused tracepoints for tracepoints that are
exported
There are sever cases where a tracepoint is created by the kernel
and used by modules. Since there's no easy way to detect if these
are truly unused since the users are in modules, if a tracepoint is
exported, assume it will eventually be used by a module. Note,
there's not many exported tracepoints so this should not be a
problem to ignore them.
- Have building of modules also detect unused tracepoints
Do not only check the main vmlinux for unused tracepoints, also
check modules. If a module is defining a tracepoint it should be
using it.
- Add the tracepoint-update program to the ignore file
The new tracepoint-update program needs to be ignored by git"
* tag 'tracepoints-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
scripts: add tracepoint-update to the list of ignores files
tracing: Add warnings for unused tracepoints for modules
tracing: Allow tracepoint-update.c to work with modules
tracepoint: Do not warn for unused event that is exported
tracing: Add a tracepoint verification check at build time
sorttable: Move ELF parsing into scripts/elf-parse.[ch]
|
||
|
Linus Torvalds
|
63e6995005 |
objtool updates for v6.19:
- klp-build livepatch module generation (Josh Poimboeuf)
Introduce new objtool features and a klp-build
script to generate livepatch modules using a
source .patch as input.
This builds on concepts from the longstanding out-of-tree
kpatch project which began in 2012 and has been used for
many years to generate livepatch modules for production kernels.
However, this is a complete rewrite which incorporates
hard-earned lessons from 12+ years of maintaining kpatch.
Key improvements compared to kpatch-build:
- Integrated with objtool: Leverages objtool's existing control-flow
graph analysis to help detect changed functions.
- Works on vmlinux.o: Supports late-linked objects, making it
compatible with LTO, IBT, and similar.
- Simplified code base: ~3k fewer lines of code.
- Upstream: No more out-of-tree #ifdef hacks, far less cruft.
- Cleaner internals: Vastly simplified logic for symbol/section/reloc
inclusion and special section extraction.
- Robust __LINE__ macro handling: Avoids false positive binary diffs
caused by the __LINE__ macro by introducing a fix-patch-lines script
which injects #line directives into the source .patch to preserve
the original line numbers at compile time.
- Disassemble code with libopcodes instead of running objdump
(Alexandre Chartre)
- Disassemble support (-d option to objtool) by Alexandre Chartre,
which supports the decoding of various Linux kernel code generation
specials such as alternatives:
17ef: sched_balance_find_dst_group+0x62f mov 0x34(%r9),%edx
17f3: sched_balance_find_dst_group+0x633 | <alternative.17f3> | X86_FEATURE_POPCNT
17f3: sched_balance_find_dst_group+0x633 | call 0x17f8 <__sw_hweight64> | popcnt %rdi,%rax
17f8: sched_balance_find_dst_group+0x638 cmp %eax,%edx
... jump table alternatives:
1895: sched_use_asym_prio+0x5 test $0x8,%ch
1898: sched_use_asym_prio+0x8 je 0x18a9 <sched_use_asym_prio+0x19>
189a: sched_use_asym_prio+0xa | <jump_table.189a> | JUMP
189a: sched_use_asym_prio+0xa | jmp 0x18ae <sched_use_asym_prio+0x1e> | nop2
189c: sched_use_asym_prio+0xc mov $0x1,%eax
18a1: sched_use_asym_prio+0x11 and $0x80,%ecx
... exception table alternatives:
native_read_msr:
5b80: native_read_msr+0x0 mov %edi,%ecx
5b82: native_read_msr+0x2 | <ex_table.5b82> | EXCEPTION
5b82: native_read_msr+0x2 | rdmsr | resume at 0x5b84 <native_read_msr+0x4>
5b84: native_read_msr+0x4 shl $0x20,%rdx
.... x86 feature flag decoding (also see the X86_FEATURE_POPCNT
example in sched_balance_find_dst_group() above):
2faaf: start_thread_common.constprop.0+0x1f jne 0x2fba4 <start_thread_common.constprop.0+0x114>
2fab5: start_thread_common.constprop.0+0x25 | <alternative.2fab5> | X86_FEATURE_ALWAYS | X86_BUG_NULL_SEG
2fab5: start_thread_common.constprop.0+0x25 | jmp 0x2faba <.altinstr_aux+0x2f4> | jmp 0x4b0 <start_thread_common.constprop.0+0x3f> | nop5
2faba: start_thread_common.constprop.0+0x2a mov $0x2b,%eax
... NOP sequence shortening:
1048e2: snapshot_write_finalize+0xc2 je 0x104917 <snapshot_write_finalize+0xf7>
1048e4: snapshot_write_finalize+0xc4 nop6
1048ea: snapshot_write_finalize+0xca nop11
1048f5: snapshot_write_finalize+0xd5 nop11
104900: snapshot_write_finalize+0xe0 mov %rax,%rcx
104903: snapshot_write_finalize+0xe3 mov 0x10(%rdx),%rax
... and much more.
- Function validation tracing support (Alexandre Chartre)
- Various -ffunction-sections fixes (Josh Poimboeuf)
- Clang AutoFDO (Automated Feedback-Directed Optimizations) support (Josh Poimboeuf)
- Misc fixes and cleanups (Borislav Petkov, Chen Ni,
Dylan Hatch, Ingo Molnar, John Wang, Josh Poimboeuf,
Pankaj Raghav, Peter Zijlstra, Thorsten Blum)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- klp-build livepatch module generation (Josh Poimboeuf)
Introduce new objtool features and a klp-build script to generate
livepatch modules using a source .patch as input.
This builds on concepts from the longstanding out-of-tree kpatch
project which began in 2012 and has been used for many years to
generate livepatch modules for production kernels. However, this is a
complete rewrite which incorporates hard-earned lessons from 12+
years of maintaining kpatch.
Key improvements compared to kpatch-build:
- Integrated with objtool: Leverages objtool's existing control-flow
graph analysis to help detect changed functions.
- Works on vmlinux.o: Supports late-linked objects, making it
compatible with LTO, IBT, and similar.
- Simplified code base: ~3k fewer lines of code.
- Upstream: No more out-of-tree #ifdef hacks, far less cruft.
- Cleaner internals: Vastly simplified logic for
symbol/section/reloc inclusion and special section extraction.
- Robust __LINE__ macro handling: Avoids false positive binary diffs
caused by the __LINE__ macro by introducing a fix-patch-lines
script which injects #line directives into the source .patch to
preserve the original line numbers at compile time.
- Disassemble code with libopcodes instead of running objdump
(Alexandre Chartre)
- Disassemble support (-d option to objtool) by Alexandre Chartre,
which supports the decoding of various Linux kernel code generation
specials such as alternatives:
17ef: sched_balance_find_dst_group+0x62f mov 0x34(%r9),%edx
17f3: sched_balance_find_dst_group+0x633 | <alternative.17f3> | X86_FEATURE_POPCNT
17f3: sched_balance_find_dst_group+0x633 | call 0x17f8 <__sw_hweight64> | popcnt %rdi,%rax
17f8: sched_balance_find_dst_group+0x638 cmp %eax,%edx
... jump table alternatives:
1895: sched_use_asym_prio+0x5 test $0x8,%ch
1898: sched_use_asym_prio+0x8 je 0x18a9 <sched_use_asym_prio+0x19>
189a: sched_use_asym_prio+0xa | <jump_table.189a> | JUMP
189a: sched_use_asym_prio+0xa | jmp 0x18ae <sched_use_asym_prio+0x1e> | nop2
189c: sched_use_asym_prio+0xc mov $0x1,%eax
18a1: sched_use_asym_prio+0x11 and $0x80,%ecx
... exception table alternatives:
native_read_msr:
5b80: native_read_msr+0x0 mov %edi,%ecx
5b82: native_read_msr+0x2 | <ex_table.5b82> | EXCEPTION
5b82: native_read_msr+0x2 | rdmsr | resume at 0x5b84 <native_read_msr+0x4>
5b84: native_read_msr+0x4 shl $0x20,%rdx
.... x86 feature flag decoding (also see the X86_FEATURE_POPCNT
example in sched_balance_find_dst_group() above):
2faaf: start_thread_common.constprop.0+0x1f jne 0x2fba4 <start_thread_common.constprop.0+0x114>
2fab5: start_thread_common.constprop.0+0x25 | <alternative.2fab5> | X86_FEATURE_ALWAYS | X86_BUG_NULL_SEG
2fab5: start_thread_common.constprop.0+0x25 | jmp 0x2faba <.altinstr_aux+0x2f4> | jmp 0x4b0 <start_thread_common.constprop.0+0x3f> | nop5
2faba: start_thread_common.constprop.0+0x2a mov $0x2b,%eax
... NOP sequence shortening:
1048e2: snapshot_write_finalize+0xc2 je 0x104917 <snapshot_write_finalize+0xf7>
1048e4: snapshot_write_finalize+0xc4 nop6
1048ea: snapshot_write_finalize+0xca nop11
1048f5: snapshot_write_finalize+0xd5 nop11
104900: snapshot_write_finalize+0xe0 mov %rax,%rcx
104903: snapshot_write_finalize+0xe3 mov 0x10(%rdx),%rax
... and much more.
- Function validation tracing support (Alexandre Chartre)
- Various -ffunction-sections fixes (Josh Poimboeuf)
- Clang AutoFDO (Automated Feedback-Directed Optimizations) support
(Josh Poimboeuf)
- Misc fixes and cleanups (Borislav Petkov, Chen Ni, Dylan Hatch, Ingo
Molnar, John Wang, Josh Poimboeuf, Pankaj Raghav, Peter Zijlstra,
Thorsten Blum)
* tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
objtool: Fix segfault on unknown alternatives
objtool: Build with disassembly can fail when including bdf.h
objtool: Trim trailing NOPs in alternative
objtool: Add wide output for disassembly
objtool: Compact output for alternatives with one instruction
objtool: Improve naming of group alternatives
objtool: Add Function to get the name of a CPU feature
objtool: Provide access to feature and flags of group alternatives
objtool: Fix address references in alternatives
objtool: Disassemble jump table alternatives
objtool: Disassemble exception table alternatives
objtool: Print addresses with alternative instructions
objtool: Disassemble group alternatives
objtool: Print headers for alternatives
objtool: Preserve alternatives order
objtool: Add the --disas=<function-pattern> action
objtool: Do not validate IBT for .return_sites and .call_sites
objtool: Improve tracing of alternative instructions
objtool: Add functions to better name alternatives
objtool: Identify the different types of alternatives
...
|
||
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Linus Torvalds
|
b04b2e7a61 |
vfs-6.19-rc1.misc
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Merge tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
"Features:
- Cheaper MAY_EXEC handling for path lookup. This elides MAY_WRITE
permission checks during path lookup and adds the
IOP_FASTPERM_MAY_EXEC flag so filesystems like btrfs can avoid
expensive permission work.
- Hide dentry_cache behind runtime const machinery.
- Add German Maglione as virtiofs co-maintainer.
Cleanups:
- Tidy up and inline step_into() and walk_component() for improved
code generation.
- Re-enable IOCB_NOWAIT writes to files. This refactors file
timestamp update logic, fixing a layering bypass in btrfs when
updating timestamps on device files and improving FMODE_NOCMTIME
handling in VFS now that nfsd started using it.
- Path lookup optimizations extracting slowpaths into dedicated
routines and adding branch prediction hints for mntput_no_expire(),
fd_install(), lookup_slow(), and various other hot paths.
- Enable clang's -fms-extensions flag, requiring a JFS rename to
avoid conflicts.
- Remove spurious exports in fs/file_attr.c.
- Stop duplicating union pipe_index declaration. This depends on the
shared kbuild branch that brings in -fms-extensions support which
is merged into this branch.
- Use MD5 library instead of crypto_shash in ecryptfs.
- Use largest_zero_folio() in iomap_dio_zero().
- Replace simple_strtol/strtoul with kstrtoint/kstrtouint in init and
initrd code.
- Various typo fixes.
Fixes:
- Fix emergency sync for btrfs. Btrfs requires an explicit sync_fs()
call with wait == 1 to commit super blocks. The emergency sync path
never passed this, leaving btrfs data uncommitted during emergency
sync.
- Use local kmap in watch_queue's post_one_notification().
- Add hint prints in sb_set_blocksize() for LBS dependency on THP"
* tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits)
MAINTAINERS: add German Maglione as virtiofs co-maintainer
fs: inline step_into() and walk_component()
fs: tidy up step_into() & friends before inlining
orangefs: use inode_update_timestamps directly
btrfs: fix the comment on btrfs_update_time
btrfs: use vfs_utimes to update file timestamps
fs: export vfs_utimes
fs: lift the FMODE_NOCMTIME check into file_update_time_flags
fs: refactor file timestamp update logic
include/linux/fs.h: trivial fix: regualr -> regular
fs/splice.c: trivial fix: pipes -> pipe's
fs: mark lookup_slow() as noinline
fs: add predicts based on nd->depth
fs: move mntput_no_expire() slowpath into a dedicated routine
fs: remove spurious exports in fs/file_attr.c
watch_queue: Use local kmap in post_one_notification()
fs: touch up predicts in path lookup
fs: move fd_install() slowpath into a dedicated routine and provide commentary
fs: hide dentry_cache behind runtime const machinery
fs: touch predicts in do_dentry_open()
...
|
||
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Josh Poimboeuf
|
93863f3f85 |
kbuild: Check for functions with ambiguous -ffunction-sections section names
Commit
|
||
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Josh Poimboeuf
|
9c7dc1dd89 |
objtool: Warn on functions with ambiguous -ffunction-sections section names
When compiled with -ffunction-sections, a function named startup() will
be placed in .text.startup. However, .text.startup is also used by the
compiler for functions with __attribute__((constructor)).
That creates an ambiguity for the vmlinux linker script, which needs to
differentiate those two cases.
Similar naming conflicts exist for functions named exit(), split(),
unlikely(), hot() and unknown().
One potential solution would be to use '#ifdef CC_USING_FUNCTION_SECTIONS'
to create two distinct implementations of the TEXT_MAIN macro. However,
-ffunction-sections can be (and is) enabled or disabled on a per-object
basis (for example via ccflags-y or AUTOFDO_PROFILE).
So the recently unified TEXT_MAIN macro (commit
|
||
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Josh Poimboeuf
|
f6a8919d61 |
vmlinux.lds: Fix TEXT_MAIN to include .text.start and friends
Since: |
||
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Ingo Molnar
|
d851f2b2b2 |
Linux 6.18-rc5
-----BEGIN PGP SIGNATURE----- iQFSBAABCgA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmkRH1seHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGUCgH/j+fMbEg618ajVS2 SWdAXZKEDVtCqN6bq9VT3g3rwk/zNgvppjMdCBqyXFpjvkGGIxlZnNgiTVuTLzvR cjl0c5C1a38lJ+DzmLjTF1TJ3t0CcA/8l2iWKu3Dm1ch2yuxm5ZcM2b9ujBholf7 pYd7jZ7JhVm5eXD7U5X03AkZPUWAIx/Nip37cO7RLGzlkRSGLB7OXq3TB2u4e2ti gDpP4O+cgOqSuS71Hz0/8T6KIVQ9IZ/qzANWAYeHZD2DQwI3OZXI1WRnc1iw401o QaMaV21NirKwAANKetvbj7FgtmpdfQs/7FA+yR7YW2ARTpkc1EXrxgMZ6NuphGKE kYQo55g= =QaZ2 -----END PGP SIGNATURE----- Merge tag 'v6.18-rc5' into objtool/core, to pick up fixes Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
|
Mateusz Guzik
|
21b561dab1
|
fs: hide dentry_cache behind runtime const machinery
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://patch.msgid.link/20251105153622.758836-1-mjguzik@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
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Josh Poimboeuf
|
6568f14cb5 |
vmlinux.lds: Exclude .text.startup and .text.exit from TEXT_MAIN
An ftrace warning was reported in ftrace_init_ool_stub(): WARNING: arch/powerpc/kernel/trace/ftrace.c:234 at ftrace_init_ool_stub+0x188/0x3f4, CPU#0: swapper/0 The problem is that the linker script is placing .text.startup in .text rather than in .init.text, due to an inadvertent match of the TEXT_MAIN '.text.[0-9a-zA-Z_]*' pattern. This bug existed for some configurations before, but is only now coming to light due to the TEXT_MAIN macro unification in commit |
||
|
Dimitri John Ledkov
|
d50f210913
|
kbuild: align modinfo section for Secureboot Authenticode EDK2 compat
Previously linker scripts would always generate vmlinuz that has sections aligned. And thus padded (correct Authenticode calculation) and unpadded calculation would be same. As in https://github.com/rhboot/pesign userspace tool would produce the same authenticode digest for both of the following commands: pesign --padding --hash --in ./arch/x86_64/boot/bzImage pesign --nopadding --hash --in ./arch/x86_64/boot/bzImage The commit |
||
|
Steven Rostedt
|
e30f8e61e2 |
tracing: Add a tracepoint verification check at build time
If a tracepoint is defined via DECLARE_TRACE() or TRACE_EVENT() but never called (via the trace_<tracepoint>() function), its metadata is still around in memory and not discarded. When created via TRACE_EVENT() the situation is worse because the TRACE_EVENT() creates metadata that can be around 5k per trace event. Having unused trace events causes several thousand of wasted bytes. Add a verifier that injects a string of the name of the tracepoint it calls that is added to the discarded section "__tracepoint_check". For every builtin tracepoint, its name (which is saved in the in-memory section "__tracepoint_strings") will have its name also in the "__tracepoint_check" section if it is used. Add a new program that is run on build called tracepoint-update. This is executed on the vmlinux.o before the __tracepoint_check section is discarded (the section is discarded before vmlinux is created). This program will create an array of each string in the __tracepoint_check section and then sort it. Then it will walk the strings in the __tracepoint_strings section and do a binary search to check if its name is in the __tracepoint_check section. If it is not, then it is unused and a warning is printed. Note, this currently only handles tracepoints that are builtin and not in modules. Enabling this currently with a given config produces: warning: tracepoint 'sched_move_numa' is unused. warning: tracepoint 'sched_stick_numa' is unused. warning: tracepoint 'sched_swap_numa' is unused. warning: tracepoint 'pelt_hw_tp' is unused. warning: tracepoint 'pelt_irq_tp' is unused. warning: tracepoint 'rcu_preempt_task' is unused. warning: tracepoint 'rcu_unlock_preempted_task' is unused. warning: tracepoint 'xdp_bulk_tx' is unused. warning: tracepoint 'xdp_redirect_map' is unused. warning: tracepoint 'xdp_redirect_map_err' is unused. warning: tracepoint 'vma_mas_szero' is unused. warning: tracepoint 'vma_store' is unused. warning: tracepoint 'hugepage_set_pmd' is unused. warning: tracepoint 'hugepage_set_pud' is unused. warning: tracepoint 'hugepage_update_pmd' is unused. warning: tracepoint 'hugepage_update_pud' is unused. warning: tracepoint 'block_rq_remap' is unused. warning: tracepoint 'xhci_dbc_handle_event' is unused. warning: tracepoint 'xhci_dbc_handle_transfer' is unused. warning: tracepoint 'xhci_dbc_gadget_ep_queue' is unused. warning: tracepoint 'xhci_dbc_alloc_request' is unused. warning: tracepoint 'xhci_dbc_free_request' is unused. warning: tracepoint 'xhci_dbc_queue_request' is unused. warning: tracepoint 'xhci_dbc_giveback_request' is unused. warning: tracepoint 'tcp_ao_wrong_maclen' is unused. warning: tracepoint 'tcp_ao_mismatch' is unused. warning: tracepoint 'tcp_ao_key_not_found' is unused. warning: tracepoint 'tcp_ao_rnext_request' is unused. warning: tracepoint 'tcp_ao_synack_no_key' is unused. warning: tracepoint 'tcp_ao_snd_sne_update' is unused. warning: tracepoint 'tcp_ao_rcv_sne_update' is unused. Some of the above is totally unused but others are not used due to their "trace_" functions being inside configs, in which case, the defined tracepoints should also be inside those same configs. Others are architecture specific but defined in generic code, where they should either be moved to the architecture or be surrounded by #ifdef for the architectures they are for. This tool could be updated to process modules in the future. I'd like to thank Mathieu Desnoyers for suggesting using strings instead of pointers, as using pointers in vmlinux.o required handling relocations and it required implementing almost a full feature linker to do so. To enable this check, run the build with: make UT=1 Note, when all the existing unused tracepoints are removed from the build, the "UT=1" will be removed and this will always be enabled when tracepoints are configured to warn on any new tracepoints. The reason this isn't always enabled now is because it will introduce a lot of warnings for the current unused tracepoints, and all bisects would end at this commit for those warnings. Link: https://lore.kernel.org/all/20250528114549.4d8a5e03@gandalf.local.home/ Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nicolas Schier <nicolas.schier@linux.dev> Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/20251022004452.920728129@kernel.org Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> # for using strings instead of pointers Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> |
||
|
Josh Poimboeuf
|
1ba9f89794 |
vmlinux.lds: Unify TEXT_MAIN, DATA_MAIN, and related macros
TEXT_MAIN, DATA_MAIN and friends are defined differently depending on whether certain config options enable -ffunction-sections and/or -fdata-sections. There's no technical reason for that beyond voodoo coding. Keeping the separate implementations adds unnecessary complexity, fragments the logic, and increases the risk of subtle bugs. Unify the macros by using the same input section patterns across all configs. This is a prerequisite for the upcoming livepatch klp-build tooling which will manually enable -ffunction-sections and -fdata-sections via KCFLAGS. Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Acked-by: Petr Mladek <pmladek@suse.com> Tested-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> |
||
|
Linus Torvalds
|
7f70725741 |
Kbuild updates for 6.18
- Extend modules.builtin.modinfo to include module aliases from MODULE_DEVICE_TABLE for builtin modules so that userspace tools (such as kmod) can verify that a particular module alias will be handled by a builtin module. - Bump the minimum version of LLVM for building the kernel to 15.0.0. - Upgrade several userspace API checks in headers_check.pl to errors. - Unify and consolidate CONFIG_WERROR / W=e handling. - Turn assembler and linker warnings into errors with CONFIG_WERROR / W=e. - Respect CONFIG_WERROR / W=e when building userspace programs (userprogs). - Enable -Werror unconditionally when building host programs (hostprogs). - Support copy_file_range() and data segment alignment in gen_init_cpio to improve performance on filesystems that support reflinks such as btrfs and XFS. - Miscellaneous small changes to scripts and configuration files. Signed-off-by: Nathan Chancellor <nathan@kernel.org> -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQR74yXHMTGczQHYypIdayaRccAalgUCaNrp6QAKCRAdayaRccAa ljxRAP4hYocKXeWsiJzkTB199P4QUGWf220a9elBmtdJEed07gD/VBnCbSOxG3RO vS8qbJHwxUFL7a+mDV8RIVXSt99NpAg= =psG/ -----END PGP SIGNATURE----- Merge tag 'kbuild-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux Pull Kbuild updates from Nathan Chancellor: - Extend modules.builtin.modinfo to include module aliases from MODULE_DEVICE_TABLE for builtin modules so that userspace tools (such as kmod) can verify that a particular module alias will be handled by a builtin module - Bump the minimum version of LLVM for building the kernel to 15.0.0 - Upgrade several userspace API checks in headers_check.pl to errors - Unify and consolidate CONFIG_WERROR / W=e handling - Turn assembler and linker warnings into errors with CONFIG_WERROR / W=e - Respect CONFIG_WERROR / W=e when building userspace programs (userprogs) - Enable -Werror unconditionally when building host programs (hostprogs) - Support copy_file_range() and data segment alignment in gen_init_cpio to improve performance on filesystems that support reflinks such as btrfs and XFS - Miscellaneous small changes to scripts and configuration files * tag 'kbuild-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (47 commits) modpost: Initialize builtin_modname to stop SIGSEGVs Documentation: kbuild: note CONFIG_DEBUG_EFI in reproducible builds kbuild: vmlinux.unstripped should always depend on .vmlinux.export.o modpost: Create modalias for builtin modules modpost: Add modname to mod_device_table alias scsi: Always define blogic_pci_tbl structure kbuild: extract modules.builtin.modinfo from vmlinux.unstripped kbuild: keep .modinfo section in vmlinux.unstripped kbuild: always create intermediate vmlinux.unstripped s390: vmlinux.lds.S: Reorder sections KMSAN: Remove tautological checks objtool: Drop noinstr hack for KCSAN_WEAK_MEMORY lib/Kconfig.debug: Drop CLANG_VERSION check from DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT riscv: Remove ld.lld version checks from many TOOLCHAIN_HAS configs riscv: Unconditionally use linker relaxation riscv: Remove version check for LTO_CLANG selects powerpc: Drop unnecessary initializations in __copy_inst_from_kernel_nofault() mips: Unconditionally select ARCH_HAS_CURRENT_STACK_POINTER arm64: Remove tautological LLVM Kconfig conditions ARM: Clean up definition of ARM_HAS_GROUP_RELOCS ... |
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Linus Torvalds
|
d2b2fea350 |
asm-generic: updates for 6.18
Two small patches for the asm-generic header files: Varad Gautam improves the MMIO tracing to be faster when the tracepoints are built into the kernel but disabled, while Qi Xi updates the DO_ONCE logic so that clearing the WARN_ONCE() flags does not change the other DO_ONCE users. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEo6/YBQwIrVS28WGKmmx57+YAGNkFAmjdrC0ACgkQmmx57+YA GNmOuQ//XvHAW5q/kBgoIxNaEAwEJn+6AnjGE/HWkyIPDEBJGOIAo02h/1BIXsIX PRGVYL/WOnhMMYAjPAGqFXF7kYjFmZx1/thFVsjVnPtkqR7AapEamLjSSmjXQTmp N0kUseD6Uv1X2IxVHcuTvFoZ/Z+fuz7RvmLtNhZ5DFnFJ4cHX2l8gEvOc1po5SX6 +Q6fwtwMhMWa57N+E90UcWJFPetZ6UUN6dIidAdDYp+lBwP2HHsvm0tzr95Rw3a1 ugAkcdSj67UyucNf3ECQ/JTtckPJBoxGSAOOpbT1f+SdO4zIHCY3TsOM7bt7Vvqp 58GbyJ4f8sKN2LwjvBrvn8qNRRzuHfTYYK66D4ahy9zvPgYYWkTKJRLSI6HEkv1j cbSWUkV0C/e1CBbTQLoGzpjKEFPHefODU0n35sG60Tf8nG2fue2wCMCCjMnbyeEP eA+dEDxM7xvXPcNDdEKqKCLCV+zm2D+CqlfdIcwvrjF2x5dt/P+zFoLO0qIN8DE7 GAMrKfjw5X5o4pe/9SD8E0hyVZnjWrZ0oc7IGT2zdAFNm/vlJ/xBuOlC8ZNNtnaJ DcAkADUKiudd5HYlC3bTThBVhEITfTacfF1qBy4T/jFzbk1l5yfQjwn+O9o71CkL j5blsdlrLOTkWfFaOq4Z2IBGWUif2K3cd/ata7J4+FX/MN2TLVM= =Vx5p -----END PGP SIGNATURE----- Merge tag 'asm-generic-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "Two small patches for the asm-generic header files: Varad Gautam improves the MMIO tracing to be faster when the tracepoints are built into the kernel but disabled, while Qi Xi updates the DO_ONCE logic so that clearing the WARN_ONCE() flags does not change the other DO_ONCE users" * tag 'asm-generic-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: once: fix race by moving DO_ONCE to separate section asm-generic/io.h: Skip trace helpers if rwmmio events are disabled |
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Qi Xi
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edcc8a38b5
|
once: fix race by moving DO_ONCE to separate section
The commit |
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Kees Cook
|
23ef9d4397 |
kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
The kernel's CFI implementation uses the KCFI ABI specifically, and is not strictly tied to a particular compiler. In preparation for GCC supporting KCFI, rename CONFIG_CFI_CLANG to CONFIG_CFI (along with associated options). Use new "transitional" Kconfig option for old CONFIG_CFI_CLANG that will enable CONFIG_CFI during olddefconfig. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20250923213422.1105654-3-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org> |
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Masahiro Yamada
|
3e86e4d74c
|
kbuild: keep .modinfo section in vmlinux.unstripped
Keep the .modinfo section during linking, but strip it from the final vmlinux. Adjust scripts/mksysmap to exclude modinfo symbols from kallsyms. This change will allow the next commit to extract the .modinfo section from the vmlinux.unstripped intermediate. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Alexey Gladkov <legion@kernel.org> Reviewed-by: Nicolas Schier <nsc@kernel.org> Link: https://patch.msgid.link/aaf67c07447215463300fccaa758904bac42f992.1758182101.git.legion@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org> |
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Steven Rostedt
|
4d6d0a6263 |
tracing: Remove redundant config HAVE_FTRACE_MCOUNT_RECORD
Ftrace is tightly coupled with architecture specific code because it requires the use of trampolines written in assembly. This means that when a new feature or optimization is made, it must be done for all architectures. To simplify the approach, CONFIG_HAVE_FTRACE_* configs are added to denote which architecture has the new enhancement so that other architectures can still function until they too have been updated. The CONFIG_HAVE_FTRACE_MCOUNT was added to help simplify the DYNAMIC_FTRACE work, but now every architecture that implements DYNAMIC_FTRACE also has HAVE_FTRACE_MCOUNT set too, making it redundant with the HAVE_DYNAMIC_FTRACE. Remove the HAVE_FTRACE_MCOUNT config and use DYNAMIC_FTRACE directly where applicable. Link: https://lore.kernel.org/all/20250703154916.48e3ada7@gandalf.local.home/ Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/20250704104838.27a18690@gandalf.local.home Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> |
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Linus Torvalds
|
90b83efa67 |
bpf-next-6.16
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Merge tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Fix and improve BTF deduplication of identical BTF types (Alan
Maguire and Andrii Nakryiko)
- Support up to 12 arguments in BPF trampoline on arm64 (Xu Kuohai and
Alexis Lothoré)
- Support load-acquire and store-release instructions in BPF JIT on
riscv64 (Andrea Parri)
- Fix uninitialized values in BPF_{CORE,PROBE}_READ macros (Anton
Protopopov)
- Streamline allowed helpers across program types (Feng Yang)
- Support atomic update for hashtab of BPF maps (Hou Tao)
- Implement json output for BPF helpers (Ihor Solodrai)
- Several s390 JIT fixes (Ilya Leoshkevich)
- Various sockmap fixes (Jiayuan Chen)
- Support mmap of vmlinux BTF data (Lorenz Bauer)
- Support BPF rbtree traversal and list peeking (Martin KaFai Lau)
- Tests for sockmap/sockhash redirection (Michal Luczaj)
- Introduce kfuncs for memory reads into dynptrs (Mykyta Yatsenko)
- Add support for dma-buf iterators in BPF (T.J. Mercier)
- The verifier support for __bpf_trap() (Yonghong Song)
* tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (135 commits)
bpf, arm64: Remove unused-but-set function and variable.
selftests/bpf: Add tests with stack ptr register in conditional jmp
bpf: Do not include stack ptr register in precision backtracking bookkeeping
selftests/bpf: enable many-args tests for arm64
bpf, arm64: Support up to 12 function arguments
bpf: Check rcu_read_lock_trace_held() in bpf_map_lookup_percpu_elem()
bpf: Avoid __bpf_prog_ret0_warn when jit fails
bpftool: Add support for custom BTF path in prog load/loadall
selftests/bpf: Add unit tests with __bpf_trap() kfunc
bpf: Warn with __bpf_trap() kfunc maybe due to uninitialized variable
bpf: Remove special_kfunc_set from verifier
selftests/bpf: Add test for open coded dmabuf_iter
selftests/bpf: Add test for dmabuf_iter
bpf: Add open coded dmabuf iterator
bpf: Add dmabuf iterator
dma-buf: Rename debugfs symbols
bpf: Fix error return value in bpf_copy_from_user_dynptr
libbpf: Use mmap to parse vmlinux BTF from sysfs
selftests: bpf: Add a test for mmapable vmlinux BTF
btf: Allow mmap of vmlinux btf
...
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Lorenz Bauer
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a539e2a6d5 |
btf: Allow mmap of vmlinux btf
User space needs access to kernel BTF for many modern features of BPF. Right now each process needs to read the BTF blob either in pieces or as a whole. Allow mmaping the sysfs file so that processes can directly access the memory allocated for it in the kernel. remap_pfn_range is used instead of vm_insert_page due to aarch64 compatibility issues. Signed-off-by: Lorenz Bauer <lmb@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Link: https://lore.kernel.org/bpf/20250520-vmlinux-mmap-v5-1-e8c941acc414@isovalent.com |
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Ard Biesheuvel
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092071e0f6 |
vmlinux.lds: Include .data.rel[.local] into .data section
When running in -fPIC mode, the compiler may decide to emit statically initialized data objects into .data.rel or .data.rel.local if they contain absolute references to global or local objects, respectively, which require fixing up at load time. This distinction is irrelevant for the kernel, so fold .data.rel and .data.rel.local into .data. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Dionna Amalie Glaze <dionnaglaze@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Loughlin <kevinloughlin@google.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250418141253.2601348-9-ardb+git@google.com |
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Linus Torvalds
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71b639af06 |
x86/fpu updates for v6.15:
- Improve crypto performance by making kernel-mode FPU reliably usable
in softirqs ((Eric Biggers)
- Fully optimize out WARN_ON_FPU() (Eric Biggers)
- Initial steps to support Support Intel APX (Advanced Performance Extensions)
(Chang S. Bae)
- Fix KASAN for arch_dup_task_struct() (Benjamin Berg)
- Refine and simplify the FPU magic number check during signal return
(Chang S. Bae)
- Fix inconsistencies in guest FPU xfeatures (Chao Gao, Stanislav Spassov)
- selftests/x86/xstate: Introduce common code for testing extended states
(Chang S. Bae)
- Misc fixes and cleanups (Borislav Petkov, Colin Ian King, Uros Bizjak)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'x86-fpu-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/fpu updates from Ingo Molnar:
- Improve crypto performance by making kernel-mode FPU reliably usable
in softirqs ((Eric Biggers)
- Fully optimize out WARN_ON_FPU() (Eric Biggers)
- Initial steps to support Support Intel APX (Advanced Performance
Extensions) (Chang S. Bae)
- Fix KASAN for arch_dup_task_struct() (Benjamin Berg)
- Refine and simplify the FPU magic number check during signal return
(Chang S. Bae)
- Fix inconsistencies in guest FPU xfeatures (Chao Gao, Stanislav
Spassov)
- selftests/x86/xstate: Introduce common code for testing extended
states (Chang S. Bae)
- Misc fixes and cleanups (Borislav Petkov, Colin Ian King, Uros
Bizjak)
* tag 'x86-fpu-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu/xstate: Fix inconsistencies in guest FPU xfeatures
x86/fpu: Clarify the "xa" symbolic name used in the XSTATE* macros
x86/fpu: Use XSAVE{,OPT,C,S} and XRSTOR{,S} mnemonics in xstate.h
x86/fpu: Improve crypto performance by making kernel-mode FPU reliably usable in softirqs
x86/fpu/xstate: Simplify print_xstate_features()
x86/fpu: Refine and simplify the magic number check during signal return
selftests/x86/xstate: Fix spelling mistake "hader" -> "header"
x86/fpu: Avoid copying dynamic FP state from init_task in arch_dup_task_struct()
vmlinux.lds.h: Remove entry to place init_task onto init_stack
selftests/x86/avx: Add AVX tests
selftests/x86/xstate: Clarify supported xstates
selftests/x86/xstate: Consolidate test invocations into a single entry
selftests/x86/xstate: Introduce signal ABI test
selftests/x86/xstate: Refactor ptrace ABI test
selftests/x86/xstate: Refactor context switching test
selftests/x86/xstate: Enumerate and name xstate components
selftests/x86/xstate: Refactor XSAVE helpers for general use
selftests/x86: Consolidate redundant signal helper functions
x86/fpu: Fix guest FPU state buffer allocation size
x86/fpu: Fully optimize out WARN_ON_FPU()
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Uros Bizjak
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6d536cad0d |
x86/percpu: Fix __per_cpu_hot_end marker
Make __per_cpu_hot_end marker point to the end of the percpu cache hot data, not to the end of the percpu cache hot section. This fixes CONFIG_MPENTIUM4 case where X86_L1_CACHE_SHIFT is set to 7 (128 bytes). Also update assert message accordingly. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Link: https://lore.kernel.org/r/20250304173455.89361-1-ubizjak@gmail.com Closes: https://lore.kernel.org/lkml/Z8a-NVJs-pm5W-mG@gmail.com/ |
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Brian Gerst
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ab2bb9c084 |
percpu: Introduce percpu hot section
Add a subsection to the percpu data for frequently accessed variables that should remain cached on each processor. These varables should not be accessed from other processors to avoid cacheline bouncing. This will replace the pcpu_hot struct on x86, and open up similar functionality to other architectures and the kernel core. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-2-brgerst@gmail.com |
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Ingo Molnar
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cfdaa618de |
Merge branch 'x86/cpu' into x86/asm, to pick up dependent commits
Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Linus Torvalds
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ad69e02128 |
Fix an objtool false positive, and objtool related
build warnings that happens on PIE-enabled architectures such as LoongArch. Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmfCCV0RHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1jHsA//RLrKlu/nvMO0l03s9ndWaunz0Nih/Z54 JJm4Ig+NLYY8VWLH+q6xfII8LT0oUeLh4OtmRj1vMhDbi2DnWozzDA1cvh6Fhyfj YG9Xgzej7ZPU43AVlItl80TbG/xfEdD5yxZx8WC6/WUI17XcpTkDC9/NG/NfrUjY 2a+A8nJk/qa/M+qCHf7ugDxMQFrOVRDDtdBSRAUbifqgygKO+AtXCIyeBfbtVkyV GEWusjO4lsyiY1dzG911h+ROIl/hp6Y3B940PSXyiwjs8JFJJplECnrnwROvRhTm xUDFeszEh40i6zHu2dzFf0up9vFCFZGpjzvMTc0Dt50i4Z3OxbxXW+Ust2YjpSms Ux+MHsH850UoXS/4QB7R2RJndqLTvsYkcu8uhOc2izVkWvTORba0+SMguKuTu1xI MDKozZxtH1DPCtMcZtNIgVlQEwsioKaHUS/PgXhdqw8+fg3ur9FEXp8Q2ubUm7XJ VJm6nF0RvFZNiIIDm81O1Z1RmmxUuAlAHWIOREaNzTSHu3ptBjBOtRrBTem2WAMa 9g1n4GoB7HI96TG36ik0/1oZhEAhawEwT/HhehVpPJyKNQooADYqhhPpfysyGJzq mp+oOdf0QYfD0+M4oqmEGN0fhIlNobK7ap2O+t7HPcJwO1Om3h6WCkyijixj6xPt cOuqhG+GKSk= =16p4 -----END PGP SIGNATURE----- Merge tag 'objtool-urgent-2025-02-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool fixes from Ingo Molnar: "Fix an objtool false positive, and objtool related build warnings that happens on PIE-enabled architectures such as LoongArch" * tag 'objtool-urgent-2025-02-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Add bch2_trans_unlocked_or_in_restart_error() to bcachefs noreturns objtool: Fix C jump table annotations for Clang vmlinux.lds: Ensure that const vars with relocations are mapped R/O |
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Benjamin Berg
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2ec01bd715 |
vmlinux.lds.h: Remove entry to place init_task onto init_stack
Since commit
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Ard Biesheuvel
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68f3ea7ee1 |
vmlinux.lds: Ensure that const vars with relocations are mapped R/O
In the kernel, there are architectures (x86, arm64) that perform boot-time relocation (for KASLR) without relying on PIE codegen. In this case, all const global objects are emitted into .rodata, including const objects with fields that will be fixed up by the boot-time relocation code. This implies that .rodata (and .text in some cases) need to be writable at boot, but they will usually be mapped read-only as soon as the boot completes. When using PIE codegen, the compiler will emit const global objects into .data.rel.ro rather than .rodata if the object contains fields that need such fixups at boot-time. This permits the linker to annotate such regions as requiring read-write access only at load time, but not at execution time (in user space), while keeping .rodata truly const (in user space, this is important for reducing the CoW footprint of dynamic executables). This distinction does not matter for the kernel, but it does imply that const data will end up in writable memory if the .data.rel.ro sections are not treated in a special way, as they will end up in the writable .data segment by default. So emit .data.rel.ro into the .rodata segment. Cc: stable@vger.kernel.org Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250221135704.431269-5-ardb+git@google.com Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> |
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Brian Gerst
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4b00c1160a |
percpu: Remove __per_cpu_load
__per_cpu_load is now always equal to __per_cpu_start. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250123190747.745588-15-brgerst@gmail.com |
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Brian Gerst
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e23cff6861 |
percpu: Remove PERCPU_VADDR()
x86-64 was the last user. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250123190747.745588-14-brgerst@gmail.com |
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Brian Gerst
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95b0916118 |
percpu: Remove PER_CPU_FIRST_SECTION
x86-64 was the last user. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250123190747.745588-13-brgerst@gmail.com |
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Masahiro Yamada
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4c56eb33e6 |
kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS
Linus observed that the symbol_request(utf8_data_table) call fails when
CONFIG_UNICODE=y and CONFIG_TRIM_UNUSED_KSYMS=y.
symbol_get() relies on the symbol data being present in the ksymtab for
symbol lookups. However, EXPORT_SYMBOL_GPL(utf8_data_table) is dropped
due to CONFIG_TRIM_UNUSED_KSYMS, as no module references it in this case.
Probably, this has been broken since commit
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Masahiro Yamada
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dbefa1f31a |
Rename .data.once to .data..once to fix resetting WARN*_ONCE
Commit |
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Masahiro Yamada
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bb43a59944 |
Rename .data.unlikely to .data..unlikely
Commit |
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Rong Xu
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d5dc958361 |
kbuild: Add Propeller configuration for kernel build
Add the build support for using Clang's Propeller optimizer. Like AutoFDO, Propeller uses hardware sampling to gather information about the frequency of execution of different code paths within a binary. This information is then used to guide the compiler's optimization decisions, resulting in a more efficient binary. The support requires a Clang compiler LLVM 19 or later, and the create_llvm_prof tool (https://github.com/google/autofdo/releases/tag/v0.30.1). This commit is limited to x86 platforms that support PMU features like LBR on Intel machines and AMD Zen3 BRS. Here is an example workflow for building an AutoFDO+Propeller optimized kernel: 1) Build the kernel on the host machine, with AutoFDO and Propeller build config CONFIG_AUTOFDO_CLANG=y CONFIG_PROPELLER_CLANG=y then $ make LLVM=1 CLANG_AUTOFDO_PROFILE=<autofdo_profile> “<autofdo_profile>” is the profile collected when doing a non-Propeller AutoFDO build. This step builds a kernel that has the same optimization level as AutoFDO, plus a metadata section that records basic block information. This kernel image runs as fast as an AutoFDO optimized kernel. 2) Install the kernel on test/production machines. 3) Run the load tests. The '-c' option in perf specifies the sample event period. We suggest using a suitable prime number, like 500009, for this purpose. For Intel platforms: $ perf record -e BR_INST_RETIRED.NEAR_TAKEN:k -a -N -b -c <count> \ -o <perf_file> -- <loadtest> For AMD platforms: The supported system are: Zen3 with BRS, or Zen4 with amd_lbr_v2 # To see if Zen3 support LBR: $ cat proc/cpuinfo | grep " brs" # To see if Zen4 support LBR: $ cat proc/cpuinfo | grep amd_lbr_v2 # If the result is yes, then collect the profile using: $ perf record --pfm-events RETIRED_TAKEN_BRANCH_INSTRUCTIONS:k -a \ -N -b -c <count> -o <perf_file> -- <loadtest> 4) (Optional) Download the raw perf file to the host machine. 5) Generate Propeller profile: $ create_llvm_prof --binary=<vmlinux> --profile=<perf_file> \ --format=propeller --propeller_output_module_name \ --out=<propeller_profile_prefix>_cc_profile.txt \ --propeller_symorder=<propeller_profile_prefix>_ld_profile.txt “create_llvm_prof” is the profile conversion tool, and a prebuilt binary for linux can be found on https://github.com/google/autofdo/releases/tag/v0.30.1 (can also build from source). "<propeller_profile_prefix>" can be something like "/home/user/dir/any_string". This command generates a pair of Propeller profiles: "<propeller_profile_prefix>_cc_profile.txt" and "<propeller_profile_prefix>_ld_profile.txt". 6) Rebuild the kernel using the AutoFDO and Propeller profile files. CONFIG_AUTOFDO_CLANG=y CONFIG_PROPELLER_CLANG=y and $ make LLVM=1 CLANG_AUTOFDO_PROFILE=<autofdo_profile> \ CLANG_PROPELLER_PROFILE_PREFIX=<propeller_profile_prefix> Co-developed-by: Han Shen <shenhan@google.com> Signed-off-by: Han Shen <shenhan@google.com> Signed-off-by: Rong Xu <xur@google.com> Suggested-by: Sriraman Tallam <tmsriram@google.com> Suggested-by: Krzysztof Pszeniczny <kpszeniczny@google.com> Suggested-by: Nick Desaulniers <ndesaulniers@google.com> Suggested-by: Stephane Eranian <eranian@google.com> Tested-by: Yonghong Song <yonghong.song@linux.dev> Tested-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> |
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Rong Xu
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2fd65f7afd |
AutoFDO: Enable machine function split optimization for AutoFDO
Enable the machine function split optimization for AutoFDO in Clang. Machine function split (MFS) is a pass in the Clang compiler that splits a function into hot and cold parts. The linker groups all cold blocks across functions together. This decreases hot code fragmentation and improves iCache and iTLB utilization. MFS requires a profile so this is enabled only for the AutoFDO builds. Co-developed-by: Han Shen <shenhan@google.com> Signed-off-by: Han Shen <shenhan@google.com> Signed-off-by: Rong Xu <xur@google.com> Suggested-by: Sriraman Tallam <tmsriram@google.com> Suggested-by: Krzysztof Pszeniczny <kpszeniczny@google.com> Tested-by: Yonghong Song <yonghong.song@linux.dev> Tested-by: Yabin Cui <yabinc@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> |
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Rong Xu
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0847420f5e |
AutoFDO: Enable -ffunction-sections for the AutoFDO build
Enable -ffunction-sections by default for the AutoFDO build. With -ffunction-sections, the compiler places each function in its own section named .text.function_name instead of placing all functions in the .text section. In the AutoFDO build, this allows the linker to utilize profile information to reorganize functions for improved utilization of iCache and iTLB. Co-developed-by: Han Shen <shenhan@google.com> Signed-off-by: Han Shen <shenhan@google.com> Signed-off-by: Rong Xu <xur@google.com> Suggested-by: Sriraman Tallam <tmsriram@google.com> Tested-by: Yonghong Song <yonghong.song@linux.dev> Tested-by: Yabin Cui <yabinc@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> |
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Rong Xu
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db0b2991ae |
vmlinux.lds.h: Add markers for text_unlikely and text_hot sections
Add markers like __hot_text_start, __hot_text_end, __unlikely_text_start, and __unlikely_text_end which will be included in System.map. These markers indicate how the compiler groups functions, providing valuable information to developers about the layout and optimization of the code. Co-developed-by: Han Shen <shenhan@google.com> Signed-off-by: Han Shen <shenhan@google.com> Signed-off-by: Rong Xu <xur@google.com> Suggested-by: Sriraman Tallam <tmsriram@google.com> Tested-by: Yonghong Song <yonghong.song@linux.dev> Tested-by: Yabin Cui <yabinc@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> |
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Rong Xu
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0043ecea23 |
vmlinux.lds.h: Adjust symbol ordering in text output section
When the -ffunction-sections compiler option is enabled, each function is placed in a separate section named .text.function_name rather than putting all functions in a single .text section. However, using -function-sections can cause problems with the linker script. The comments included in include/asm-generic/vmlinux.lds.h note these issues.: “TEXT_MAIN here will match .text.fixup and .text.unlikely if dead code elimination is enabled, so these sections should be converted to use ".." first.” It is unclear whether there is a straightforward method for converting a suffix to "..". This patch modifies the order of subsections within the text output section. Specifically, it changes current order: .text.hot, .text, .text_unlikely, .text.unknown, .text.asan to the new order: .text.asan, .text.unknown, .text_unlikely, .text.hot, .text Here is the rationale behind the new layout: The majority of the code resides in three sections: .text.hot, .text, and .text.unlikely, with .text.unknown containing a negligible amount. .text.asan is only generated in ASAN builds. The primary goal is to group code segments based on their execution frequency (hotness). First, we want to place .text.hot adjacent to .text. Since we cannot put .text.hot after .text (Due to constraints with -ffunction-sections, placing .text.hot after .text is problematic), we need to put .text.hot before .text. Then it comes to .text.unlikely, we cannot put it after .text (same -ffunction-sections issue) . Therefore, we position .text.unlikely before .text.hot. .text.unknown and .tex.asan follow the same logic. This revised ordering effectively reverses the original arrangement (for .text.unlikely, .text.unknown, and .tex.asan), maintaining a similar level of affinity between sections. It also places .text.hot section at the beginning of a page to better utilize the TLB entry. Note that the limitation arises because the linker script employs glob patterns instead of regular expressions for string matching. While there is a method to maintain the current order using complex patterns, this significantly complicates the pattern and increases the likelihood of errors. This patch also changes vmlinux.lds.S for the sparc64 architecture to accommodate specific symbol placement requirements. Co-developed-by: Han Shen <shenhan@google.com> Signed-off-by: Han Shen <shenhan@google.com> Signed-off-by: Rong Xu <xur@google.com> Suggested-by: Sriraman Tallam <tmsriram@google.com> Suggested-by: Krzysztof Pszeniczny <kpszeniczny@google.com> Tested-by: Yonghong Song <yonghong.song@linux.dev> Tested-by: Yabin Cui <yabinc@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> |
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Linus Torvalds
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348325d644 |
asm-generic updates for 6.12
These are only two small patches, one cleanup for arch/alpha and a preparation patch cleaning up the handling of runtime constants in the linker scripts. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEiK/NIGsWEZVxh/FrYKtH/8kJUicFAmboHV0ACgkQYKtH/8kJ UifHfhAAqTHHxxe+HiphGBPHN0ODyLVUs7fOQHtLOSmJlQa6x1TCR/+1nL1kTDbe j6EcIRxZrllQZ+jZBA8z2XsAmjjBLUxCB4yu6oxYJh8OdFyqeVM/myZEr2TAyb0o A3D9b+rfnY8sr9XaFHSHGWbh4c33cGQhACumHVAjtPvU06Voskq4pAf9ZnpGkNBe AdKNTVG6+w84dKUNuzXcexP8d7SnsXNfd6T9+evtW/M+fziWzs3aPQr+GZED96E5 8IRldXi2nzIwm9LT5IzZAt+QvpVb2Qob1+rej9p5WpptGp840CROTo61SwaYHCMV DDxTlmADsApWJQ3B5gDu6QS2jXT4eeOrY3JI2baeCyOV6auj15UXKiWc2QVoHOVU 6+PzlSFuLatI6WsxXfOcD0o3bfQXMKS6zCC/4eD7Y/SmmMqBbL5+d9sU5lwkiOFl swoswF4HTwo5d6NdkSuJOt6KA/V8a68lBhKYBXHu2yuLi/LDNOaipEvBHQLzfnlY 91e5DtDiHK9CYDNkwiR+bV9rQnhA535JSlfR8VtpU/SJTTjyF+dkt9JGPdivXoIA 8Zv+DN/oyrahUtCrgzzPXahOuBrfD/WfIajsvpEK6vNPuBhscsZFg/thc70FMIXo qn8Dmpi/CnDWFNOy0xO0cbYWrGBGn9E7kzbSZ78tUIjPUmmEKfk= =OOMl -----END PGP SIGNATURE----- Merge tag 'asm-generic-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "These are only two small patches, one cleanup for arch/alpha and a preparation patch cleaning up the handling of runtime constants in the linker scripts" * tag 'asm-generic-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: runtime constants: move list of constants to vmlinux.lds.h alpha: no need to include asm/xchg.h twice |
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Tejun Heo
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649e980dad |
Merge branch 'bpf/master' into for-6.12
Pull bpf/master to receive
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Jann Horn
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92a10d3861 |
runtime constants: move list of constants to vmlinux.lds.h
Refactor the list of constant variables into a macro. This should make it easier to add more constants in the future. Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> |
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Linus Torvalds
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b6547e5486 |
runtime constants: deal with old decrepit linkers
The runtime constants linker script depended on documented linker behavior [1]: "If an output section’s name is the same as the input section’s name and is representable as a C identifier, then the linker will automatically PROVIDE two symbols: __start_SECNAME and __stop_SECNAME, where SECNAME is the name of the section. These indicate the start address and end address of the output section respectively" to just automatically define the symbol names for the bounds of the runtime constant arrays. It turns out that this isn't actually something we can rely on, with old linkers not generating these automatic symbols. It looks to have been introduced in binutils-2.29 back in 2017, and we still support building with versions all the way back to binutils-2.25 (from 2015). And yes, Oleg actually seems to be using such ancient versions of binutils. So instead of depending on the implicit symbols from "section names match and are representable C identifiers", just do this all manually. It's not like it causes us any extra pain, we already have to do that for all the other sections that we use that often have special characters in them. Reported-and-tested-by: Oleg Nesterov <oleg@redhat.com> Link: https://sourceware.org/binutils/docs/ld/Input-Section-Example.html [1] Link: https://lore.kernel.org/all/20240802114518.GA20924@redhat.com/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |