The objtool merge in commit 6f612579be ("Merge tag 'objtool-core ...")
generated a semantic conflict that was not resolved.
The btrfs_assertfail() entry was removed from the noreturn list in
commit b831306b3b ("btrfs: print assertion failure report and stack
trace from the same line") because btrfs_assertfail() was changed from a
noreturn function into a macro.
The noreturn list was then moved from check.c to noreturns.h in commit
6245ce4ab6 ("objtool: Move noreturn function list to separate file"),
and should be removed from that post-merge as well.
Do it explicitly.
Cc: David Sterba <dsterba@suse.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Build footprint & performance improvements:
- Reduce memory usage with CONFIG_DEBUG_INFO=y
In the worst case of an allyesconfig+CONFIG_DEBUG_INFO=y kernel, DWARF
creates almost 200 million relocations, ballooning objtool's peak heap
usage to 53GB. These patches reduce that to 25GB.
On a distro-type kernel with kernel IBT enabled, they reduce objtool's
peak heap usage from 4.2GB to 2.8GB.
These changes also improve the runtime significantly.
- Debuggability improvements:
- Add the unwind_debug command-line option, for more extend unwinding
debugging output.
- Limit unreachable warnings to once per function
- Add verbose option for disassembling affected functions
- Include backtrace in verbose mode
- Detect missing __noreturn annotations
- Ignore exc_double_fault() __noreturn warnings
- Remove superfluous global_noreturns entries
- Move noreturn function list to separate file
- Add __kunit_abort() to noreturns
- Unwinder improvements:
- Allow stack operations in UNWIND_HINT_UNDEFINED regions
- drm/vmwgfx: Add unwind hints around RBP clobber
- Cleanups:
- Move the x86 entry thunk restore code into thunk functions
- x86/unwind/orc: Use swap() instead of open coding it
- Remove unnecessary/unused variables
- Fixes for modern stack canary handling
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=uNnc
-----END PGP SIGNATURE-----
Merge tag 'objtool-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molar:
"Build footprint & performance improvements:
- Reduce memory usage with CONFIG_DEBUG_INFO=y
In the worst case of an allyesconfig+CONFIG_DEBUG_INFO=y kernel,
DWARF creates almost 200 million relocations, ballooning objtool's
peak heap usage to 53GB. These patches reduce that to 25GB.
On a distro-type kernel with kernel IBT enabled, they reduce
objtool's peak heap usage from 4.2GB to 2.8GB.
These changes also improve the runtime significantly.
Debuggability improvements:
- Add the unwind_debug command-line option, for more extend unwinding
debugging output
- Limit unreachable warnings to once per function
- Add verbose option for disassembling affected functions
- Include backtrace in verbose mode
- Detect missing __noreturn annotations
- Ignore exc_double_fault() __noreturn warnings
- Remove superfluous global_noreturns entries
- Move noreturn function list to separate file
- Add __kunit_abort() to noreturns
Unwinder improvements:
- Allow stack operations in UNWIND_HINT_UNDEFINED regions
- drm/vmwgfx: Add unwind hints around RBP clobber
Cleanups:
- Move the x86 entry thunk restore code into thunk functions
- x86/unwind/orc: Use swap() instead of open coding it
- Remove unnecessary/unused variables
Fixes for modern stack canary handling"
* tag 'objtool-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits)
x86/orc: Make the is_callthunk() definition depend on CONFIG_BPF_JIT=y
objtool: Skip reading DWARF section data
objtool: Free insns when done
objtool: Get rid of reloc->rel[a]
objtool: Shrink elf hash nodes
objtool: Shrink reloc->sym_reloc_entry
objtool: Get rid of reloc->jump_table_start
objtool: Get rid of reloc->addend
objtool: Get rid of reloc->type
objtool: Get rid of reloc->offset
objtool: Get rid of reloc->idx
objtool: Get rid of reloc->list
objtool: Allocate relocs in advance for new rela sections
objtool: Add for_each_reloc()
objtool: Don't free memory in elf_close()
objtool: Keep GElf_Rel[a] structs synced
objtool: Add elf_create_section_pair()
objtool: Add mark_sec_changed()
objtool: Fix reloc_hash size
objtool: Consolidate rel/rela handling
...
This KUnit update for Linux 6.5-rc1 consists of:
- kunit_add_action() API to defer a call until test exit.
- Update document to add kunit_add_action() usage notes.
- Changes to always run cleanup from a test kthread.
- Documentation updates to clarify cleanup usage
- assertions should not be used in cleanup
- Documentation update to clearly indicate that exit
functions should run even if init fails
- Several fixes and enhancements to existing tests.
-----BEGIN PGP SIGNATURE-----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=rYT5
-----END PGP SIGNATURE-----
Merge tag 'linux-kselftest-kunit-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull KUnit updates from Shuah Khan:
- kunit_add_action() API to defer a call until test exit
- Update document to add kunit_add_action() usage notes
- Changes to always run cleanup from a test kthread
- Documentation updates to clarify cleanup usage (assertions should not
be used in cleanup)
- Documentation update to clearly indicate that exit functions should
run even if init fails
- Several fixes and enhancements to existing tests
* tag 'linux-kselftest-kunit-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
MAINTAINERS: Add source tree entry for kunit
Documentation: kunit: Rename references to kunit_abort()
kunit: Move kunit_abort() call out of kunit_do_failed_assertion()
kunit: Fix obsolete name in documentation headers (func->action)
Documentation: Kunit: add MODULE_LICENSE to sample code
kunit: Update kunit_print_ok_not_ok function
kunit: Fix reporting of the skipped parameterized tests
kunit/test: Add example test showing parameterized testing
Documentation: kunit: Add usage notes for kunit_add_action()
kunit: kmalloc_array: Use kunit_add_action()
kunit: executor_test: Use kunit_add_action()
kunit: Add kunit_add_action() to defer a call until test exit
kunit: example: Provide example exit functions
Documentation: kunit: Warn that exit functions run even if init fails
Documentation: kunit: Note that assertions should not be used in cleanup
kunit: Always run cleanup from a test kthread
Documentation: kunit: Modular tests should not depend on KUNIT=y
kunit: tool: undo type subscripts for subprocess.Popen
of the ERMS CPUID flag. AMD decoupled them with a BIOS setting so decouple
that dependency in the kernel code too
- Teach the alternatives machinery to handle relocations
- Make debug_alternative accept flags in order to see only that set of
patching done one is interested in
- Other fixes, cleanups and optimizations to the patching code
-----BEGIN PGP SIGNATURE-----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=mH38
-----END PGP SIGNATURE-----
Merge tag 'x86_alternatives_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 instruction alternatives updates from Borislav Petkov:
- Up until now the Fast Short Rep Mov optimizations implied the
presence of the ERMS CPUID flag. AMD decoupled them with a BIOS
setting so decouple that dependency in the kernel code too
- Teach the alternatives machinery to handle relocations
- Make debug_alternative accept flags in order to see only that set of
patching done one is interested in
- Other fixes, cleanups and optimizations to the patching code
* tag 'x86_alternatives_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/alternative: PAUSE is not a NOP
x86/alternatives: Add cond_resched() to text_poke_bp_batch()
x86/nospec: Shorten RESET_CALL_DEPTH
x86/alternatives: Add longer 64-bit NOPs
x86/alternatives: Fix section mismatch warnings
x86/alternative: Optimize returns patching
x86/alternative: Complicate optimize_nops() some more
x86/alternative: Rewrite optimize_nops() some
x86/lib/memmove: Decouple ERMS from FSRM
x86/alternative: Support relocations in alternatives
x86/alternative: Make debug-alternative selective
Assertions reports are split into two parts, the exact file and location
of the condition and then the stack trace printed from
btrfs_assertfail(). This means all the stack traces report the same line
and this is what's typically reported by various tools, making it harder
to distinguish the reports.
[403.2467] assertion failed: refcount_read(&block_group->refs) == 1, in fs/btrfs/block-group.c:4259
[403.2479] ------------[ cut here ]------------
[403.2484] kernel BUG at fs/btrfs/messages.c:259!
[403.2488] invalid opcode: 0000 [#1] PREEMPT SMP KASAN
[403.2493] CPU: 2 PID: 23202 Comm: umount Not tainted 6.2.0-rc4-default+ #67
[403.2499] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552-rebuilt.opensuse.org 04/01/2014
[403.2509] RIP: 0010:btrfs_assertfail+0x19/0x1b [btrfs]
...
[403.2595] Call Trace:
[403.2598] <TASK>
[403.2601] btrfs_free_block_groups.cold+0x52/0xae [btrfs]
[403.2608] close_ctree+0x6c2/0x761 [btrfs]
[403.2613] ? __wait_for_common+0x2b8/0x360
[403.2618] ? btrfs_cleanup_one_transaction.cold+0x7a/0x7a [btrfs]
[403.2626] ? mark_held_locks+0x6b/0x90
[403.2630] ? lockdep_hardirqs_on_prepare+0x13d/0x200
[403.2636] ? __call_rcu_common.constprop.0+0x1ea/0x3d0
[403.2642] ? trace_hardirqs_on+0x2d/0x110
[403.2646] ? __call_rcu_common.constprop.0+0x1ea/0x3d0
[403.2652] generic_shutdown_super+0xb0/0x1c0
[403.2657] kill_anon_super+0x1e/0x40
[403.2662] btrfs_kill_super+0x25/0x30 [btrfs]
[403.2668] deactivate_locked_super+0x4c/0xc0
By making btrfs_assertfail a macro we'll get the same line number for
the BUG output:
[63.5736] assertion failed: 0, in fs/btrfs/super.c:1572
[63.5758] ------------[ cut here ]------------
[63.5782] kernel BUG at fs/btrfs/super.c:1572!
[63.5807] invalid opcode: 0000 [#2] PREEMPT SMP KASAN
[63.5831] CPU: 0 PID: 859 Comm: mount Tainted: G D 6.3.0-rc7-default+ #2062
[63.5868] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
[63.5905] RIP: 0010:btrfs_mount+0x24/0x30 [btrfs]
[63.5964] RSP: 0018:ffff88800e69fcd8 EFLAGS: 00010246
[63.5982] RAX: 000000000000002d RBX: ffff888008fc1400 RCX: 0000000000000000
[63.6004] RDX: 0000000000000000 RSI: ffffffffb90fd868 RDI: ffffffffbcc3ff20
[63.6026] RBP: ffffffffc081b200 R08: 0000000000000001 R09: ffff88800e69fa27
[63.6046] R10: ffffed1001cd3f44 R11: 0000000000000001 R12: ffff888005a3c370
[63.6062] R13: ffffffffc058e830 R14: 0000000000000000 R15: 00000000ffffffff
[63.6081] FS: 00007f7b3561f800(0000) GS:ffff88806c600000(0000) knlGS:0000000000000000
[63.6105] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[63.6120] CR2: 00007fff83726e10 CR3: 0000000002a9e000 CR4: 00000000000006b0
[63.6137] Call Trace:
[63.6143] <TASK>
[63.6148] legacy_get_tree+0x80/0xd0
[63.6158] vfs_get_tree+0x43/0x120
[63.6166] do_new_mount+0x1f3/0x3d0
[63.6176] ? do_add_mount+0x140/0x140
[63.6187] ? cap_capable+0xa4/0xe0
[63.6197] path_mount+0x223/0xc10
This comes at a cost of bloating the final btrfs.ko module due all the
inlining, as long as assertions are compiled in. This is a must for
debugging builds but this is often enabled on release builds too.
Release build:
text data bss dec hex filename
1251676 20317 16088 1288081 13a791 pre/btrfs.ko
1260612 29473 16088 1306173 13ee3d post/btrfs.ko
DELTA: +8936
CC: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
Objtool doesn't use DWARF at all, and the DWARF sections' data take up a
lot of memory. Skip reading them.
Note this only skips the DWARF base sections, not the rela sections.
The relas are needed because their symbol references may need to be
reindexed if any local symbols get added by elf_create_symbol().
Also note the DWARF data will eventually be read by libelf anyway, when
writing the object file. But that's fine, the goal here is to reduce
*peak* memory usage, and the previous patch (which freed insn memory)
gave some breathing room. So the allocation gets shifted to a later
time, resulting in lower peak memory usage.
With allyesconfig + CONFIG_DEBUG_INFO:
- Before: peak heap memory consumption: 29.93G
- After: peak heap memory consumption: 25.47G
Link: https://lore.kernel.org/r/52a9698835861dd35f2ec35c49f96d0bb39fb177.1685464332.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
When creating an annotation section, allocate the reloc section data at
the beginning. This simplifies the data model a bit and also saves
memory due to the removal of malloc() in elf_rebuild_reloc_section().
With allyesconfig + CONFIG_DEBUG_INFO:
- Before: peak heap memory consumption: 53.49G
- After: peak heap memory consumption: 49.02G
Link: https://lore.kernel.org/r/048e908f3ede9b66c15e44672b6dda992b1dae3e.1685464332.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
The GElf_Rel[a] structs have more similarities than differences. It's
safe to hard-code the assumptions about their shared fields as they will
never change. Consolidate their handling where possible, getting rid of
duplicated code.
Also, at least for now we only ever create rela sections, so simplify
the relocation creation code to be rela-only.
Link: https://lore.kernel.org/r/dcabf6df400ca500ea929f1e4284f5e5ec0b27c8.1685464332.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
- The term "reloc" is overloaded to mean both "an instance of struct
reloc" and "a reloc section". Change the latter to "rsec".
- For variable names, use "sec" for regular sections and "rsec" for rela
sections to prevent them getting mixed up.
- For struct reloc variables, use "reloc" instead of "rel" everywhere
for consistency.
Link: https://lore.kernel.org/r/8b790e403df46f445c21003e7893b8f53b99a6f3.1685464332.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
There are several places where warnings variables are not needed,
remove them and directly return 0.
Signed-off-by: Lu Hongfei <luhongfei@vivo.com>
Link: https://lore.kernel.org/r/20230530075649.21661-1-luhongfei@vivo.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
This is a hack, but it works for now.
Problem is, exc_double_fault() may or may not return, depending on
whether CONFIG_X86_ESPFIX64 is set. But objtool has no visibility to
the kernel config.
"Fix" it by silencing the exc_double_fault() __noreturn warning.
This removes the following warning:
vmlinux.o: warning: objtool: xenpv_exc_double_fault+0xd: exc_double_fault() is missing a __noreturn annotation
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lore.kernel.org/r/a45b085071d3a7d049a20f9e78754452336ecbe8.1681853186.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Unreachable instruction warnings are limited to once per object file.
That no longer makes sense for vmlinux validation, which might have
more unreachable instructions lurking in other places. Change it to
once per function.
Note this affects some other (much rarer) non-fatal warnings as well.
In general I think one-warning-per-function makes sense, as related
warnings can accumulate quickly and we want to eventually get back to
failing the build with -Werror anyway.
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lore.kernel.org/r/9d38f881bfc34e031c74e4e90064ccb3e49f599a.1681853186.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
A little while ago someone (Kirill) ran into the whole 'alternatives don't
do relocations nonsense' again and I got annoyed enough to actually look
at the code.
Since the whole alternative machinery already fully decodes the
instructions it is simple enough to adjust immediates and displacement
when needed. Specifically, the immediates for IP modifying instructions
(JMP, CALL, Jcc) and the displacement for RIP-relative instructions.
[ bp: Massage comment some more and get rid of third loop in
apply_relocation(). ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230208171431.313857925@infradead.org
- Mark arch_cpu_idle_dead() __noreturn, make all architectures & drivers that did
this inconsistently follow this new, common convention, and fix all the fallout
that objtool can now detect statically.
- Fix/improve the ORC unwinder becoming unreliable due to UNWIND_HINT_EMPTY ambiguity,
split it into UNWIND_HINT_END_OF_STACK and UNWIND_HINT_UNDEFINED to resolve it.
- Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code.
- Generate ORC data for __pfx code
- Add more __noreturn annotations to various kernel startup/shutdown/panic functions.
- Misc improvements & fixes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=NwEV
-----END PGP SIGNATURE-----
Merge tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- Mark arch_cpu_idle_dead() __noreturn, make all architectures &
drivers that did this inconsistently follow this new, common
convention, and fix all the fallout that objtool can now detect
statically
- Fix/improve the ORC unwinder becoming unreliable due to
UNWIND_HINT_EMPTY ambiguity, split it into UNWIND_HINT_END_OF_STACK
and UNWIND_HINT_UNDEFINED to resolve it
- Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code
- Generate ORC data for __pfx code
- Add more __noreturn annotations to various kernel startup/shutdown
and panic functions
- Misc improvements & fixes
* tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
x86/hyperv: Mark hv_ghcb_terminate() as noreturn
scsi: message: fusion: Mark mpt_halt_firmware() __noreturn
x86/cpu: Mark {hlt,resume}_play_dead() __noreturn
btrfs: Mark btrfs_assertfail() __noreturn
objtool: Include weak functions in global_noreturns check
cpu: Mark nmi_panic_self_stop() __noreturn
cpu: Mark panic_smp_self_stop() __noreturn
arm64/cpu: Mark cpu_park_loop() and friends __noreturn
x86/head: Mark *_start_kernel() __noreturn
init: Mark start_kernel() __noreturn
init: Mark [arch_call_]rest_init() __noreturn
objtool: Generate ORC data for __pfx code
x86/linkage: Fix padding for typed functions
objtool: Separate prefix code from stack validation code
objtool: Remove superfluous dead_end_function() check
objtool: Add symbol iteration helpers
objtool: Add WARN_INSN()
scripts/objdump-func: Support multiple functions
context_tracking: Fix KCSAN noinstr violation
objtool: Add stackleak instrumentation to uaccess safe list
...
-----BEGIN PGP SIGNATURE-----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=Jt7p
-----END PGP SIGNATURE-----
Merge tag 'for-6.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"Mostly core changes and cleanups, some notable fixes and two
performance improvements in directory logging.
The IO path cleanups are removing or refactoring old code, scrub main
loop has been completely rewritten also refactoring old code.
There are some changes to non-btrfs code, mostly trivial, the cgroup
punt bio logic is only moved from generic code.
Performance improvements:
- improve logging changes in a directory during one transaction,
avoid iterating over items and reduce lock contention (fsync time
4x lower)
- when logging directory entries during one transaction, reduce
locking of subvolume trees by checking tree-log instead
(improvement in throughput and latency for concurrent access to a
subvolume)
Notable fixes:
- dev-replace:
- properly honor read mode when requested to avoid reading from
source device
- target device won't be used for eventual read repair, this is
unreliable for NODATASUM files
- when there are unpaired (and unrepairable) metadata during
replace, exit early with error and don't try to finish whole
operation
- scrub ioctl properly rejects unknown flags
- fix global block reserve calculations
- fix partial direct io write when there's a page fault in the
middle, iomap will try to continue with partial request but the
btrfs part did not match that, this can lead to zeros written
instead of data
Core changes:
- io path:
- continued cleanups and refactoring around bio handling
- extent io submit path simplifications and cleanups
- flush write path simplifications and cleanups
- rework logic of passing sync mode of bio, with further cleanups
- rewrite scrub code flow, restructure how the stripes are enumerated
and verified in a more unified way
- allow to set lower threshold for block group reclaim in debug mode
to aid zoned mode testing
- remove obsolete time-based delayed ref throttling logic when
truncating items
- DREW locks are not using percpu variables anymore
- more warning fixes (-Wmaybe-uninitialized)
- u64 division simplifications
- error handling improvements
Non-btrfs code changes:
- push cgroup punt bio logic to btrfs code (there was no other user
of that), the functionality can be now selected separately by
BLK_CGROUP_PUNT_BIO
- crc32c_impl removed after removing last uses in btrfs code
- add btrfs_assertfail() to objtool table"
* tag 'for-6.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (147 commits)
btrfs: mark btrfs_assertfail() __noreturn
btrfs: fix uninitialized variable warnings
btrfs: use log root when iterating over index keys when logging directory
btrfs: avoid iterating over all indexes when logging directory
btrfs: dev-replace: error out if we have unrepaired metadata error during
btrfs: remove pointless loop at btrfs_get_next_valid_item()
btrfs: scrub: reject unsupported scrub flags
btrfs: reinterpret async discard iops_limit=0 as no delay
btrfs: set default discard iops_limit to 1000
btrfs: remove unused raid56 functions which were dedicated for scrub
btrfs: scrub: remove scrub_bio structure
btrfs: scrub: remove scrub_block and scrub_sector structures
btrfs: scrub: remove the old scrub recheck code
btrfs: scrub: remove the old writeback infrastructure
btrfs: scrub: remove scrub_parity structure
btrfs: scrub: use scrub_stripe to implement RAID56 P/Q scrub
btrfs: scrub: switch scrub_simple_mirror() to scrub_stripe infrastructure
btrfs: scrub: introduce helper to queue a stripe for scrub
btrfs: scrub: introduce error reporting functionality for scrub_stripe
btrfs: scrub: introduce a writeback helper for scrub_stripe
...
still a fair amount going on, including:
- Reorganizing the architecture-specific documentation under
Documentation/arch. This makes the structure match the source directory
and helps to clean up the mess that is the top-level Documentation
directory a bit. This work creates the new directory and moves x86 and
most of the less-active architectures there. The current plan is to move
the rest of the architectures in 6.5, with the patches going through the
appropriate subsystem trees.
- Some more Spanish translations and maintenance of the Italian
translation.
- A new "Kernel contribution maturity model" document from Ted.
- A new tutorial on quickly building a trimmed kernel from Thorsten.
Plus the usual set of updates and fixes.
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmRGze0PHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5Y/VsH/RyWqinorRVFZmHqRJMRhR0j7hE2pAgK5prE
dGXYVtHHNQ+25thNaqhZTOLYFbSX6ii2NG7sLRXmyOTGIZrhUCFFXCHkuq4ZUypR
gJpMUiKQVT4dhln3gIZ0k09NSr60gz8UTcq895N9UFpUdY1SCDhbCcLc4uXTRajq
NrdgFaHWRkPb+gBRbXOExYm75DmCC6Ny5AyGo2rXfItV//ETjWIJVQpJhlxKrpMZ
3LgpdYSLhEFFnFGnXJ+EAPJ7gXDi2Tg5DuPbkvJyFOTouF3j4h8lSS9l+refMljN
xNRessv+boge/JAQidS6u8F2m2ESSqSxisv/0irgtKIMJwXaoX4=
=1//8
-----END PGP SIGNATURE-----
Merge tag 'docs-6.4' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"Commit volume in documentation is relatively low this time, but there
is still a fair amount going on, including:
- Reorganize the architecture-specific documentation under
Documentation/arch
This makes the structure match the source directory and helps to
clean up the mess that is the top-level Documentation directory a
bit. This work creates the new directory and moves x86 and most of
the less-active architectures there.
The current plan is to move the rest of the architectures in 6.5,
with the patches going through the appropriate subsystem trees.
- Some more Spanish translations and maintenance of the Italian
translation
- A new "Kernel contribution maturity model" document from Ted
- A new tutorial on quickly building a trimmed kernel from Thorsten
Plus the usual set of updates and fixes"
* tag 'docs-6.4' of git://git.lwn.net/linux: (47 commits)
media: Adjust column width for pdfdocs
media: Fix building pdfdocs
docs: clk: add documentation to log which clocks have been disabled
docs: trace: Fix typo in ftrace.rst
Documentation/process: always CC responsible lists
docs: kmemleak: adjust to config renaming
ELF: document some de-facto PT_* ABI quirks
Documentation: arm: remove stih415/stih416 related entries
docs: turn off "smart quotes" in the HTML build
Documentation: firmware: Clarify firmware path usage
docs/mm: Physical Memory: Fix grammar
Documentation: Add document for false sharing
dma-api-howto: typo fix
docs: move m68k architecture documentation under Documentation/arch/
docs: move parisc documentation under Documentation/arch/
docs: move ia64 architecture docs under Documentation/arch/
docs: Move arc architecture docs under Documentation/arch/
docs: move nios2 documentation under Documentation/arch/
docs: move openrisc documentation under Documentation/arch/
docs: move superh documentation under Documentation/arch/
...
The old 'copy_user_generic_unrolled' function was oddly implemented for
largely historical reasons: it had been largely based on the uncached
copy case, which has some other concerns.
For example, the __copy_user_nocache() function uses 'movnti' for the
destination stores, and those want the destination to be aligned. In
contrast, the regular copy function doesn't really care, and trying to
align things only complicates matters.
Also, like the clear_user function, the copy function had some odd
handling of the repeat counts, complicating the exception handling for
no really good reason. So as with clear_user, just write it to keep all
the byte counts in the %rcx register, exactly like the 'rep movs'
functionality that this replaces.
Unlike a real 'rep movs', we do allow for this to trash a few temporary
registers to not have to unnecessarily save/restore registers on the
stack.
And like the clearing case, rename this to what it now clearly is:
'rep_movs_alternative', and make it one coherent function, so that it
shows up as such in profiles (instead of the odd split between
"copy_user_generic_unrolled" and "copy_user_short_string", the latter of
which was not about strings at all, and which was shared with the
uncached case).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The old version was oddly written to have the repeat count in multiple
registers. So instead of taking advantage of %rax being zero, it had
some sub-counts in it. All just for a "single word clearing" loop,
which isn't even efficient to begin with.
So get rid of those games, and just keep all the state in the same
registers we got it in (and that we should return things in). That not
only makes this act much more like 'rep stos' (which this function is
replacing), but makes it much easier to actually do the obvious loop
unrolling.
Also rename the function from the now nonsensical 'clear_user_original'
to what it now clearly is: 'rep_stos_alternative'.
End result: if we don't have a fast 'rep stosb', at least we can have a
fast fallback for it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This does the same thing for the user copies as commit 0db7058e8e
("x86/clear_user: Make it faster") did for clear_user(). In other
words, it inlines the "rep movs" case when X86_FEATURE_FSRM is set,
avoiding the function call entirely.
In order to do that, it makes the calling convention for the out-of-line
case ("copy_user_generic_unrolled") match the 'rep movs' calling
convention, although it does also end up clobbering a number of
additional registers.
Also, to simplify code sharing in the low-level assembly with the
__copy_user_nocache() function (that uses the normal C calling
convention), we end up with a kind of mixed return value for the
low-level asm code: it will return the result in both %rcx (to work as
an alternative for the 'rep movs' case), _and_ in %rax (for the nocache
case).
We could avoid this by wrapping __copy_user_nocache() callers in an
inline asm, but since the cost is just an extra register copy, it's
probably not worth it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is preparatory work for inlining the 'rep movs' case, but also a
cleanup. The __copy_user_nocache() function was mis-used by the rdma
code to do uncached kernel copies that don't actually want user copies
at all, and as a result doesn't want the stac/clac either.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The modern target to use is FSRS (Fast Short REP STOS), and the other
cases should only be used for bigger areas (ie mainly things like page
clearing).
Note! This changes the conditional for the inlining from FSRM ("fast
short rep movs") to FSRS ("fast short rep stos").
We'll have a separate fixup for AMD microarchitectures that have a good
'rep stosb' yet do not set the new Intel-specific FSRS bit (because FSRM
was there first).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Annotate the function prototype and definition as noreturn to prevent
objtool warnings like:
vmlinux.o: warning: objtool: hyperv_init+0x55c: unreachable instruction
Also, as per Josh's suggestion, add it to the global_noreturns list.
As a comparison, an objdump output without the annotation:
[...]
1b63: mov $0x1,%esi
1b68: xor %edi,%edi
1b6a: callq ffffffff8102f680 <hv_ghcb_terminate>
1b6f: jmpq ffffffff82f217ec <hyperv_init+0x9c> # unreachable
1b74: cmpq $0xffffffffffffffff,-0x702a24(%rip)
[...]
Now, after adding the __noreturn to the function prototype:
[...]
17df: callq ffffffff8102f6d0 <hv_ghcb_negotiate_protocol>
17e4: test %al,%al
17e6: je ffffffff82f21bb9 <hyperv_init+0x469>
[...] <many insns>
1bb9: mov $0x1,%esi
1bbe: xor %edi,%edi
1bc0: callq ffffffff8102f680 <hv_ghcb_terminate>
1bc5: nopw %cs:0x0(%rax,%rax,1) # end of function
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/32453a703dfcf0d007b473c9acbf70718222b74b.1681342859.git.jpoimboe@kernel.org
If a global function doesn't return, and its prototype has the
__noreturn attribute, its weak counterpart must also not return so that
it matches the prototype and meets call site expectations.
To properly follow the compiled control flow at the call sites, change
the global_noreturns check to include both global and weak functions.
On the other hand, if a weak function isn't in global_noreturns, assume
the prototype doesn't have __noreturn. Even if the weak function
doesn't return, call sites treat it like a returnable function.
Fixes the following warning:
kernel/sched/build_policy.o: warning: objtool: do_idle() falls through to next function play_idle_precise()
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lore.kernel.org/r/ede3460d63f4a65d282c86f1175bd2662c2286ba.1681342859.git.jpoimboe@kernel.org
In preparation for improving objtool's handling of weak noreturn
functions, mark start_kernel(), arch_call_rest_init(), and rest_init()
__noreturn.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/7194ed8a989a85b98d92e62df660f4a90435a723.1681342859.git.jpoimboe@kernel.org
Allow unwinding from prefix code by copying the CFI from the starting
instruction of the corresponding function. Even when the NOPs are
replaced, they're still stack-invariant instructions so the same ORC
entry can be reused everywhere.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/bc3344e51f3e87102f1301a0be0f72a7689ea4a4.1681331135.git.jpoimboe@kernel.org
It's easier to use and also gives easy access to the instruction's
containing function, which is useful for printing that function's
symbol. It will also be useful in the future for rate-limiting and
disassembly of warned functions.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/2eaa3155c90fba683d8723599f279c46025b75f3.1681325924.git.jpoimboe@kernel.org
If a function has a large stack frame, the stackleak plugin adds a call
to stackleak_track_stack() after the prologue.
This function may be called in uaccess-enabled code. Add it to the
uaccess safe list.
Fixes the following warning:
vmlinux.o: warning: objtool: kasan_report+0x12: call to stackleak_track_stack() with UACCESS enabled
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/42e9b487ef89e9b237fd5220ad1c7cf1a2ad7eb8.1681320562.git.jpoimboe@kernel.org
Commit 468af56a7b ("objtool: Support addition to set CFA base") was
added as a preparatory patch for arm64 support, but that support never
came. It triggers a false positive warning on x86, so just revert it
for now.
Fixes the following warning:
vmlinux.o: warning: objtool: cdce925_regmap_i2c_write+0xdb: stack state mismatch: cfa1=4+120 cfa2=5+40
Fixes: 468af56a7b ("objtool: Support addition to set CFA base")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/oe-kbuild-all/202304080538.j5G6h1AB-lkp@intel.com/
Move the x86 documentation under Documentation/arch/ as a way of cleaning
up the top-level directory and making the structure of our docs more
closely match the structure of the source directories it describes.
All in-kernel references to the old paths have been updated.
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Mark reported that the ORC unwinder incorrectly marks an unwind as
reliable when the unwind terminates prematurely in the dark corners of
return_to_handler() due to lack of information about the next frame.
The problem is UNWIND_HINT_EMPTY is used in two different situations:
1) The end of the kernel stack unwind before hitting user entry, boot
code, or fork entry
2) A blind spot in ORC coverage where the unwinder has to bail due to
lack of information about the next frame
The ORC unwinder has no way to tell the difference between the two.
When it encounters an undefined stack state with 'end=1', it blindly
marks the stack reliable, which can break the livepatch consistency
model.
Fix it by splitting UNWIND_HINT_EMPTY into UNWIND_HINT_UNDEFINED and
UNWIND_HINT_END_OF_STACK.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/fd6212c8b450d3564b855e1cb48404d6277b4d9f.1677683419.git.jpoimboe@kernel.org
The ENTRY unwind hint type is serving double duty as both an empty
unwind hint and an unret validation annotation.
Unret validation is unrelated to unwinding. Separate it out into its own
annotation.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/ff7448d492ea21b86d8a90264b105fbd0d751077.1677683419.git.jpoimboe@kernel.org
Before commit 076cbf5d2163 ("x86/xen: don't let xen_pv_play_dead()
return"), in Xen, when a previously offlined CPU was brought back
online, it unexpectedly resumed execution where it left off in the
middle of the idle loop.
There were some hacks to make that work, but the behavior was surprising
as do_idle() doesn't expect an offlined CPU to return from the dead (in
arch_cpu_idle_dead()).
Now that Xen has been fixed, and the arch-specific implementations of
arch_cpu_idle_dead() also don't return, give it a __noreturn attribute.
This will cause the compiler to complain if an arch-specific
implementation might return. It also improves code generation for both
caller and callee.
Also fixes the following warning:
vmlinux.o: warning: objtool: do_idle+0x25f: unreachable instruction
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/60d527353da8c99d4cf13b6473131d46719ed16d.1676358308.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
- Shrink 'struct instruction', to improve objtool performance & memory
footprint.
- Other maximum memory usage reductions - this makes the build both faster,
and fixes kernel build OOM failures on allyesconfig and similar configs
when they try to build the final (large) vmlinux.o.
- Fix ORC unwinding when a kprobe (INT3) is set on a stack-modifying
single-byte instruction (PUSH/POP or LEAVE). This requires the
extension of the ORC metadata structure with a 'signal' field.
- Misc fixes & cleanups.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=bpPY
-----END PGP SIGNATURE-----
Merge tag 'objtool-core-2023-03-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- Shrink 'struct instruction', to improve objtool performance & memory
footprint
- Other maximum memory usage reductions - this makes the build both
faster, and fixes kernel build OOM failures on allyesconfig and
similar configs when they try to build the final (large) vmlinux.o
- Fix ORC unwinding when a kprobe (INT3) is set on a stack-modifying
single-byte instruction (PUSH/POP or LEAVE). This requires the
extension of the ORC metadata structure with a 'signal' field
- Misc fixes & cleanups
* tag 'objtool-core-2023-03-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
objtool: Fix ORC 'signal' propagation
objtool: Remove instruction::list
x86: Fix FILL_RETURN_BUFFER
objtool: Fix overlapping alternatives
objtool: Union instruction::{call_dest,jump_table}
objtool: Remove instruction::reloc
objtool: Shrink instruction::{type,visited}
objtool: Make instruction::alts a single-linked list
objtool: Make instruction::stack_ops a single-linked list
objtool: Change arch_decode_instruction() signature
x86/entry: Fix unwinding from kprobe on PUSH/POP instruction
x86/unwind/orc: Add 'signal' field to ORC metadata
objtool: Optimize layout of struct special_alt
objtool: Optimize layout of struct symbol
objtool: Allocate multiple structures with calloc()
objtool: Make struct check_options static
objtool: Make struct entries[] static and const
objtool: Fix HOSTCC flag usage
objtool: Properly support make V=1
objtool: Install libsubcmd in build
...
F_SEAL_EXEC") which permits the setting of the memfd execute bit at
memfd creation time, with the option of sealing the state of the X bit.
- Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset()
thread-safe for pmd unshare") which addresses a rare race condition
related to PMD unsharing.
- Several folioification patch serieses from Matthew Wilcox, Vishal
Moola, Sidhartha Kumar and Lorenzo Stoakes
- Johannes Weiner has a series ("mm: push down lock_page_memcg()") which
does perform some memcg maintenance and cleanup work.
- SeongJae Park has added DAMOS filtering to DAMON, with the series
"mm/damon/core: implement damos filter". These filters provide users
with finer-grained control over DAMOS's actions. SeongJae has also done
some DAMON cleanup work.
- Kairui Song adds a series ("Clean up and fixes for swap").
- Vernon Yang contributed the series "Clean up and refinement for maple
tree".
- Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It
adds to MGLRU an LRU of memcgs, to improve the scalability of global
reclaim.
- David Hildenbrand has added some userfaultfd cleanup work in the
series "mm: uffd-wp + change_protection() cleanups".
- Christoph Hellwig has removed the generic_writepages() library
function in the series "remove generic_writepages".
- Baolin Wang has performed some maintenance on the compaction code in
his series "Some small improvements for compaction".
- Sidhartha Kumar is doing some maintenance work on struct page in his
series "Get rid of tail page fields".
- David Hildenbrand contributed some cleanup, bugfixing and
generalization of pte management and of pte debugging in his series "mm:
support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with swap
PTEs".
- Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation
flag in the series "Discard __GFP_ATOMIC".
- Sergey Senozhatsky has improved zsmalloc's memory utilization with his
series "zsmalloc: make zspage chain size configurable".
- Joey Gouly has added prctl() support for prohibiting the creation of
writeable+executable mappings. The previous BPF-based approach had
shortcomings. See "mm: In-kernel support for memory-deny-write-execute
(MDWE)".
- Waiman Long did some kmemleak cleanup and bugfixing in the series
"mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF".
- T.J. Alumbaugh has contributed some MGLRU cleanup work in his series
"mm: multi-gen LRU: improve".
- Jiaqi Yan has provided some enhancements to our memory error
statistics reporting, mainly by presenting the statistics on a per-node
basis. See the series "Introduce per NUMA node memory error
statistics".
- Mel Gorman has a second and hopefully final shot at fixing a CPU-hog
regression in compaction via his series "Fix excessive CPU usage during
compaction".
- Christoph Hellwig does some vmalloc maintenance work in the series
"cleanup vfree and vunmap".
- Christoph Hellwig has removed block_device_operations.rw_page() in ths
series "remove ->rw_page".
- We get some maple_tree improvements and cleanups in Liam Howlett's
series "VMA tree type safety and remove __vma_adjust()".
- Suren Baghdasaryan has done some work on the maintainability of our
vm_flags handling in the series "introduce vm_flags modifier functions".
- Some pagemap cleanup and generalization work in Mike Rapoport's series
"mm, arch: add generic implementation of pfn_valid() for FLATMEM" and
"fixups for generic implementation of pfn_valid()"
- Baoquan He has done some work to make /proc/vmallocinfo and
/proc/kcore better represent the real state of things in his series
"mm/vmalloc.c: allow vread() to read out vm_map_ram areas".
- Jason Gunthorpe rationalized the GUP system's interface to the rest of
the kernel in the series "Simplify the external interface for GUP".
- SeongJae Park wishes to migrate people from DAMON's debugfs interface
over to its sysfs interface. To support this, we'll temporarily be
printing warnings when people use the debugfs interface. See the series
"mm/damon: deprecate DAMON debugfs interface".
- Andrey Konovalov provided the accurately named "lib/stackdepot: fixes
and clean-ups" series.
- Huang Ying has provided a dramatic reduction in migration's TLB flush
IPI rates with the series "migrate_pages(): batch TLB flushing".
- Arnd Bergmann has some objtool fixups in "objtool warning fixes".
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCY/PoPQAKCRDdBJ7gKXxA
jlvpAPsFECUBBl20qSue2zCYWnHC7Yk4q9ytTkPB/MMDrFEN9wD/SNKEm2UoK6/K
DmxHkn0LAitGgJRS/W9w81yrgig9tAQ=
=MlGs
-----END PGP SIGNATURE-----
Merge tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- Daniel Verkamp has contributed a memfd series ("mm/memfd: add
F_SEAL_EXEC") which permits the setting of the memfd execute bit at
memfd creation time, with the option of sealing the state of the X
bit.
- Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset()
thread-safe for pmd unshare") which addresses a rare race condition
related to PMD unsharing.
- Several folioification patch serieses from Matthew Wilcox, Vishal
Moola, Sidhartha Kumar and Lorenzo Stoakes
- Johannes Weiner has a series ("mm: push down lock_page_memcg()")
which does perform some memcg maintenance and cleanup work.
- SeongJae Park has added DAMOS filtering to DAMON, with the series
"mm/damon/core: implement damos filter".
These filters provide users with finer-grained control over DAMOS's
actions. SeongJae has also done some DAMON cleanup work.
- Kairui Song adds a series ("Clean up and fixes for swap").
- Vernon Yang contributed the series "Clean up and refinement for maple
tree".
- Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It
adds to MGLRU an LRU of memcgs, to improve the scalability of global
reclaim.
- David Hildenbrand has added some userfaultfd cleanup work in the
series "mm: uffd-wp + change_protection() cleanups".
- Christoph Hellwig has removed the generic_writepages() library
function in the series "remove generic_writepages".
- Baolin Wang has performed some maintenance on the compaction code in
his series "Some small improvements for compaction".
- Sidhartha Kumar is doing some maintenance work on struct page in his
series "Get rid of tail page fields".
- David Hildenbrand contributed some cleanup, bugfixing and
generalization of pte management and of pte debugging in his series
"mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with
swap PTEs".
- Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation
flag in the series "Discard __GFP_ATOMIC".
- Sergey Senozhatsky has improved zsmalloc's memory utilization with
his series "zsmalloc: make zspage chain size configurable".
- Joey Gouly has added prctl() support for prohibiting the creation of
writeable+executable mappings.
The previous BPF-based approach had shortcomings. See "mm: In-kernel
support for memory-deny-write-execute (MDWE)".
- Waiman Long did some kmemleak cleanup and bugfixing in the series
"mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF".
- T.J. Alumbaugh has contributed some MGLRU cleanup work in his series
"mm: multi-gen LRU: improve".
- Jiaqi Yan has provided some enhancements to our memory error
statistics reporting, mainly by presenting the statistics on a
per-node basis. See the series "Introduce per NUMA node memory error
statistics".
- Mel Gorman has a second and hopefully final shot at fixing a CPU-hog
regression in compaction via his series "Fix excessive CPU usage
during compaction".
- Christoph Hellwig does some vmalloc maintenance work in the series
"cleanup vfree and vunmap".
- Christoph Hellwig has removed block_device_operations.rw_page() in
ths series "remove ->rw_page".
- We get some maple_tree improvements and cleanups in Liam Howlett's
series "VMA tree type safety and remove __vma_adjust()".
- Suren Baghdasaryan has done some work on the maintainability of our
vm_flags handling in the series "introduce vm_flags modifier
functions".
- Some pagemap cleanup and generalization work in Mike Rapoport's
series "mm, arch: add generic implementation of pfn_valid() for
FLATMEM" and "fixups for generic implementation of pfn_valid()"
- Baoquan He has done some work to make /proc/vmallocinfo and
/proc/kcore better represent the real state of things in his series
"mm/vmalloc.c: allow vread() to read out vm_map_ram areas".
- Jason Gunthorpe rationalized the GUP system's interface to the rest
of the kernel in the series "Simplify the external interface for
GUP".
- SeongJae Park wishes to migrate people from DAMON's debugfs interface
over to its sysfs interface. To support this, we'll temporarily be
printing warnings when people use the debugfs interface. See the
series "mm/damon: deprecate DAMON debugfs interface".
- Andrey Konovalov provided the accurately named "lib/stackdepot: fixes
and clean-ups" series.
- Huang Ying has provided a dramatic reduction in migration's TLB flush
IPI rates with the series "migrate_pages(): batch TLB flushing".
- Arnd Bergmann has some objtool fixups in "objtool warning fixes".
* tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (505 commits)
include/linux/migrate.h: remove unneeded externs
mm/memory_hotplug: cleanup return value handing in do_migrate_range()
mm/uffd: fix comment in handling pte markers
mm: change to return bool for isolate_movable_page()
mm: hugetlb: change to return bool for isolate_hugetlb()
mm: change to return bool for isolate_lru_page()
mm: change to return bool for folio_isolate_lru()
objtool: add UACCESS exceptions for __tsan_volatile_read/write
kmsan: disable ftrace in kmsan core code
kasan: mark addr_has_metadata __always_inline
mm: memcontrol: rename memcg_kmem_enabled()
sh: initialize max_mapnr
m68k/nommu: add missing definition of ARCH_PFN_OFFSET
mm: percpu: fix incorrect size in pcpu_obj_full_size()
maple_tree: reduce stack usage with gcc-9 and earlier
mm: page_alloc: call panic() when memoryless node allocation fails
mm: multi-gen LRU: avoid futile retries
migrate_pages: move THP/hugetlb migration support check to simplify code
migrate_pages: batch flushing TLB
migrate_pages: share more code between _unmap and _move
...
There have been some recently reported ORC unwinder warnings like:
WARNING: can't access registers at entry_SYSCALL_64_after_hwframe+0x63/0xcd
WARNING: stack going in the wrong direction? at __sys_setsockopt+0x2c6/0x5b0 net/socket.c:2271
And a KASAN warning:
BUG: KASAN: stack-out-of-bounds in unwind_next_frame (arch/x86/include/asm/ptrace.h:136 arch/x86/kernel/unwind_orc.c:455)
It turns out the 'signal' bit isn't getting propagated from the unwind
hints to the ORC entries, making the unwinder confused at times.
Fixes: ffb1b4a410 ("x86/unwind/orc: Add 'signal' field to ORC metadata")
Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/97eef9db60cd86d376a9a40d49d77bb67a8f6526.1676579666.git.jpoimboe@kernel.org
Things like ALTERNATIVE_{2,3}() generate multiple alternatives on the
same place, objtool would override the first orig_alt_group with the
second (or third), failing to check the CFI among all the different
variants.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org> # build only
Tested-by: Thomas Weißschuh <linux@weissschuh.net> # compile and run
Link: https://lore.kernel.org/r/20230208172245.711471461@infradead.org
In preparation to changing struct instruction around a bit, avoid
passing it's members by pointer and instead pass the whole thing.
A cleanup in it's own right too.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org> # build only
Tested-by: Thomas Weißschuh <linux@weissschuh.net> # compile and run
Link: https://lore.kernel.org/r/20230208172245.291087549@infradead.org
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCY/GzaAAKCRCAXGG7T9hj
vhgtAP96ax9EV49/kCST52z9yGfGUA+giq/9Jm6bwHlP3PZXVAD/Wfhfp1HbxzFp
CqXG7veXU+uGVP3lbpbYKNPV9DIOdgQ=
=K+0Q
-----END PGP SIGNATURE-----
Merge tag 'for-linus-6.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
- help deprecate the /proc/xen files by making the related information
available via sysfs
- mark the Xen variants of play_dead "noreturn"
- support a shared Xen platform interrupt
- several small cleanups and fixes
* tag 'for-linus-6.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: sysfs: make kobj_type structure constant
x86/Xen: drop leftover VM-assist uses
xen: Replace one-element array with flexible-array member
xen/grant-dma-iommu: Implement a dummy probe_device() callback
xen/pvcalls-back: fix permanently masked event channel
xen: Allow platform PCI interrupt to be shared
x86/xen/time: prefer tsc as clocksource when it is invariant
x86/xen: mark xen_pv_play_dead() as __noreturn
x86/xen: don't let xen_pv_play_dead() return
drivers/xen/hypervisor: Expose Xen SIF flags to userspace
tall calls properly which can be static calls too
- Add proper struct alt_instr.flags which controls different aspects of
insn patching behavior
-----BEGIN PGP SIGNATURE-----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=XUqC
-----END PGP SIGNATURE-----
Merge tag 'x86_alternatives_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm alternatives updates from Borislav Petkov:
- Teach the static_call patching infrastructure to handle conditional
tall calls properly which can be static calls too
- Add proper struct alt_instr.flags which controls different aspects of
insn patching behavior
* tag 'x86_alternatives_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/static_call: Add support for Jcc tail-calls
x86/alternatives: Teach text_poke_bp() to patch Jcc.d32 instructions
x86/alternatives: Introduce int3_emulate_jcc()
x86/alternatives: Add alt_instr.flags
A lot of the tsan helpers are already excempt from the UACCESS warnings,
but some more functions were added that need the same thing:
kernel/kcsan/core.o: warning: objtool: __tsan_volatile_read16+0x0: call to __tsan_unaligned_read16() with UACCESS enabled
kernel/kcsan/core.o: warning: objtool: __tsan_volatile_write16+0x0: call to __tsan_unaligned_write16() with UACCESS enabled
vmlinux.o: warning: objtool: __tsan_unaligned_volatile_read16+0x4: call to __tsan_unaligned_read16() with UACCESS enabled
vmlinux.o: warning: objtool: __tsan_unaligned_volatile_write16+0x4: call to __tsan_unaligned_write16() with UACCESS enabled
As Marco points out, these functions don't even call each other
explicitly but instead gcc (but not clang) notices the functions
being identical and turns one symbol into a direct branch to the
other.
Link: https://lkml.kernel.org/r/20230215130058.3836177-4-arnd@kernel.org
Fixes: 75d75b7a4d ("kcsan: Support distinguishing volatile accesses")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mark xen_pv_play_dead() and related to that xen_cpu_bringup_again()
as "__noreturn".
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221125063248.30256-3-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Add a 'signal' field which allows unwind hints to specify whether the
instruction pointer should be taken literally (like for most interrupts
and exceptions) rather than decremented (like for call stack return
addresses) when used to find the next ORC entry.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/d2c5ec4d83a45b513d8fd72fab59f1a8cfa46871.1676068346.git.jpoimboe@kernel.org
For mysterious raisins I listed the new __asan_mem*() functions as
being uaccess safe, this is giving objtool fails on KASAN builds
because these functions call out to the actual __mem*() functions
which are not marked uaccess safe.
Removing it doesn't make the robots unhappy.
Fixes: 69d4c0d321 ("entry, kasan, x86: Disallow overriding mem*() functions")
Reported-by: "Paul E. McKenney" <paulmck@kernel.org>
Bisected-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230126182302.GA687063@paulmck-ThinkPad-P17-Gen-1
Reduce the size of struct symbol on x86_64 from 208 to 200 bytes.
This structure is allocated a lot and never freed.
This reduces maximum memory usage while processing vmlinux.o from
2919716 KB to 2917988 KB (-0.5%) on my notebooks "localmodconfig".
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20221216-objtool-memory-v2-6-17968f85a464@weissschuh.net
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
By using calloc() instead of malloc() in a loop, libc does not have to
keep around bookkeeping information for each single structure.
This reduces maximum memory usage while processing vmlinux.o from
3153325 KB to 3035668 KB (-3.7%) on my notebooks "localmodconfig".
Note this introduces memory leaks, because some additional structs get
added to the lists later after reading the symbols and sections from the
original object. Luckily we don't really care about memory leaks in
objtool.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20221216-objtool-memory-v2-3-17968f85a464@weissschuh.net
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
HOSTCC is always wanted when building objtool. Setting CC to HOSTCC
happens after tools/scripts/Makefile.include is included, meaning
flags (like CFLAGS) are set assuming say CC is gcc, but then it can be
later set to HOSTCC which may be clang. tools/scripts/Makefile.include
is needed for host set up and common macros in objtool's
Makefile. Rather than override the CC variable to HOSTCC, just pass CC
as HOSTCC to the sub-makes of Makefile.build, the libsubcmd builds and
also to the linkage step.
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20230126190606.40739-4-irogers@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmPW7E8eHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGf7MIAI0JnHN9WvtEukSZ
E6j6+cEGWxsvD6q0g3GPolaKOCw7hlv0pWcFJFcUAt0jebspMdxV2oUGJ8RYW7Lg
nCcHvEVswGKLAQtQSWw52qotW6fUfMPsNYYB5l31sm1sKH4Cgss0W7l2HxO/1LvG
TSeNHX53vNAZ8pVnFYEWCSXC9bzrmU/VALF2EV00cdICmfvjlgkELGXoLKJJWzUp
s63fBHYGGURSgwIWOKStoO6HNo0j/F/wcSMx8leY8qDUtVKHj4v24EvSgxUSDBER
ch3LiSQ6qf4sw/z7pqruKFthKOrlNmcc0phjiES0xwwGiNhLv0z3rAhc4OM2cgYh
SDc/Y/c=
=zpaD
-----END PGP SIGNATURE-----
Merge tag 'v6.2-rc6' into sched/core, to pick up fixes
Pick up fixes before merging another batch of cpuidle updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Q variable was being used but never correctly set up. Add the
setting up and use in place of @.
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20230126190606.40739-3-irogers@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Including from tools/lib can create inadvertent dependencies. Install
libsubcmd in the objtool build and then include the headers from
there.
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20230126190606.40739-2-irogers@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Some out-of-tree modules still do not use module_init() / module_exit()
macros and simply create functions with magic names init_module() and
cleanup_module() instead. As a result, these functions are not recognized
as indirect call targets by objtool and such module fails to load into an
IBT enabled kernel.
This old way is not even documented any more but it is cleaner to issue
a warning than to let the module fail on load without obvious reason.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230118105215.B9DA960514@lion.mk-sys.cz
