Commit Graph

609 Commits

Author SHA1 Message Date
Linus Torvalds 2aff7c706c Objtool changes for v6.4:
- 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-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmRK1x0RHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1ghxQ/+IkCynMYtdF5OG9YwbcGJqsPSfOPMEcEM
 pUSFYg+gGPBDT/fJfcVSqvUtdnWbLC2kXt9yiswXz3X3J2nmNkBk5YKQftsNDcul
 TmKeqIIAK51XTncpegKH0EGnOX63oZ9Vxa8CTPdDlb+YF23Km2FoudGRI9F5qbUd
 LoraXqGYeiaeySkGyWmZVl6Uc8dIxnMkTN3H/oI9aB6TOrsi059hAtFcSaFfyemP
 c4LqXXCH7k2baiQt+qaLZ8cuZVG/+K5r2N2cmjO5kmJc6ynIaFnfMe4XxZLjp5LT
 /PulYI15bXkvSARKx5CRh/CDHMOx5Blw+ASO0RhWbdy0WH4ZhhcaVF5AeIpPW86a
 1LBcz97rMp72WmvKgrJeVO1r9+ll4SI6/YKGJRsxsCMdP3hgFpqntXyVjTFNdTM1
 0gH6H5v55x06vJHvhtTk8SR3PfMTEM2fRU5jXEOrGowoGifx+wNUwORiwj6LE3KQ
 SKUdT19RNzoW3VkFxhgk65ThK1S7YsJUKRoac3YdhttpqqqtFV//erenrZoR4k/p
 vzvKy68EQ7RCNyD5wNWNFe0YjeJl5G8gQ8bUm4Xmab7djjgz+pn4WpQB8yYKJLAo
 x9dqQ+6eUbw3Hcgk6qQ9E+r/svbulnAL0AeALAWK/91DwnZ2mCzKroFkLN7napKi
 fRho4CqzrtM=
 =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
  ...
2023-04-28 14:02:54 -07:00
Linus Torvalds 85d7ab2463 for-6.4-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmRHC3gACgkQxWXV+ddt
 WDvI/A//ZzREEE0wNexbuidoTacDVXVJ6LBb2K1eP+HUKfsmd6GYWQDJ9x/ExpKb
 T1ehLibCYWLeYxEREFbjXI3x9G8mrvLzvzsqXs/MzJPkmEF1igPddFztidBwvLQH
 ey/Bh+cra2bpVhRhkX0Cf09/q/YWp17/d14ZxxW60PMfyhx8RWXejXhHkulOPVv8
 +3FL8E0kc2Zjx9ioUwOy/i18LR6YzsCNVXoHzUZuWyWM4A7NG2TZR6FhuLSjlWSZ
 3RAnROwr+8i5nR0xchcyYaVMO2LMbqH6mBtHnXCtxCr+4pFrfrvKym+CQco/Xriz
 v1y/xDc23XeYXLCVhb0beJ6uRcjaM9+gvDF1oVBSJEv6V7sQr/tEGo/8QRehfEfT
 FTro7Lf89R1GOa1IBSkv/T5S25d9LlIID3/g7PbcUBtXNKvLAjDAGTH9bzL4HS5x
 /MKwN80GvaGs1KyEfUndbVPIpAwNFDYZPHM7nw1x+JTkIBcHgfjRyAMAC9jrJd0D
 730W04c+0nXZtQGtKKsxc3U8y4ewzSJAKx9t7Vgo7+1P6dSRnzvJee3x/5kXV9Yn
 MhxxzYDfIN9EcWbASdSm11gY5WZdG3an609pO7nc1T2K4Tuo0SPs4xOR7c3xuZrY
 MN5z3QFWyI2ustUuTG+nsd5J81j76DEmj5ymWQfG3SBplTneDM0=
 =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
  ...
2023-04-26 09:13:44 -07:00
Linus Torvalds c23f28975a Commit volume in documentation is relatively low this time, but there is
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/
  ...
2023-04-24 12:35:49 -07:00
Linus Torvalds 427fda2c8a x86: improve on the non-rep 'copy_user' function
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>
2023-04-18 17:05:28 -07:00
Linus Torvalds 8c9b6a88b7 x86: improve on the non-rep 'clear_user' function
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>
2023-04-18 17:05:28 -07:00
Linus Torvalds 577e6a7fd5 x86: inline the 'rep movs' in user copies for the FSRM case
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>
2023-04-18 17:05:28 -07:00
Linus Torvalds 3639a53558 x86: move stac/clac from user copy routines into callers
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>
2023-04-18 17:05:28 -07:00
Linus Torvalds d2c95f9d68 x86: don't use REP_GOOD or ERMS for user memory clearing
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>
2023-04-18 17:05:28 -07:00
Josh Poimboeuf f372463124 btrfs: mark btrfs_assertfail() __noreturn
Fixes a bunch of warnings including:

  vmlinux.o: warning: objtool: select_reloc_root+0x314: unreachable instruction
  vmlinux.o: warning: objtool: finish_inode_if_needed+0x15b1: unreachable instruction
  vmlinux.o: warning: objtool: get_bio_sector_nr+0x259: unreachable instruction
  vmlinux.o: warning: objtool: raid_wait_read_end_io+0xc26: unreachable instruction
  vmlinux.o: warning: objtool: raid56_parity_alloc_scrub_rbio+0x37b: unreachable instruction
  ...

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202302210709.IlXfgMpX-lkp@intel.com/
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 19:52:19 +02:00
Guilherme G. Piccoli 611d4c716d x86/hyperv: Mark hv_ghcb_terminate() as noreturn
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
2023-04-14 17:31:28 +02:00
Josh Poimboeuf 6e36a56a5f scsi: message: fusion: Mark mpt_halt_firmware() __noreturn
mpt_halt_firmware() doesn't return.  Mark it as such.

Fixes the following warnings:

  vmlinux.o: warning: objtool: mptscsih_abort+0x7f4: unreachable instruction
  vmlinux.o: warning: objtool: mptctl_timeout_expired+0x310: unreachable instruction

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Mark Rutland <mark.rutland@arm.com>
Debugged-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/d8129817423422355bf30e90dadc6764261b53e0.1681342859.git.jpoimboe@kernel.org
2023-04-14 17:31:27 +02:00
Josh Poimboeuf 52668badd3 x86/cpu: Mark {hlt,resume}_play_dead() __noreturn
Fixes the following warning:

  vmlinux.o: warning: objtool: resume_play_dead+0x21: unreachable instruction

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/r/ce1407c4bf88b1334fe40413126343792a77ca50.1681342859.git.jpoimboe@kernel.org
2023-04-14 17:31:27 +02:00
Josh Poimboeuf 09c5ae30d0 btrfs: Mark btrfs_assertfail() __noreturn
Fixes a bunch of warnings including:

  vmlinux.o: warning: objtool: select_reloc_root+0x314: unreachable instruction
  vmlinux.o: warning: objtool: finish_inode_if_needed+0x15b1: unreachable instruction
  vmlinux.o: warning: objtool: get_bio_sector_nr+0x259: unreachable instruction
  vmlinux.o: warning: objtool: raid_wait_read_end_io+0xc26: unreachable instruction
  vmlinux.o: warning: objtool: raid56_parity_alloc_scrub_rbio+0x37b: unreachable instruction
  ...

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/r/960bd9c0c9e3cfc409ba9c35a17644b11b832956.1681342859.git.jpoimboe@kernel.org
2023-04-14 17:31:26 +02:00
Josh Poimboeuf 1c47c8758a objtool: Include weak functions in global_noreturns check
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
2023-04-14 17:31:26 +02:00
Josh Poimboeuf 27dea14c7f cpu: Mark nmi_panic_self_stop() __noreturn
In preparation for improving objtool's handling of weak noreturn
functions, mark nmi_panic_self_stop() __noreturn.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/316fc6dfab5a8c4e024c7185484a1ee5fb0afb79.1681342859.git.jpoimboe@kernel.org
2023-04-14 17:31:26 +02:00
Josh Poimboeuf 7412a60dec cpu: Mark panic_smp_self_stop() __noreturn
In preparation for improving objtool's handling of weak noreturn
functions, mark panic_smp_self_stop() __noreturn.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/92d76ab5c8bf660f04fdcd3da1084519212de248.1681342859.git.jpoimboe@kernel.org
2023-04-14 17:31:25 +02:00
Josh Poimboeuf 4208d2d798 x86/head: Mark *_start_kernel() __noreturn
Now that start_kernel() is __noreturn, mark its chain of callers
__noreturn.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/c2525f96b88be98ee027ee0291d58003036d4120.1681342859.git.jpoimboe@kernel.org
2023-04-14 17:31:24 +02:00
Josh Poimboeuf 25a6917ca6 init: Mark start_kernel() __noreturn
Now that arch_call_rest_init() is __noreturn, mark its caller
start_kernel() __noreturn.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/7069acf026a195f26a88061227fba5a3b0337b9a.1681342859.git.jpoimboe@kernel.org
2023-04-14 17:31:23 +02:00
Josh Poimboeuf 9ea7e6b62c init: Mark [arch_call_]rest_init() __noreturn
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
2023-04-14 17:31:23 +02:00
Josh Poimboeuf 5743654f5e objtool: Generate ORC data for __pfx code
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
2023-04-14 16:08:30 +02:00
Josh Poimboeuf bd456a1bed objtool: Separate prefix code from stack validation code
Simplify the prefix code by moving it after
validate_reachable_instructions().

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/d7f31ac2de462d0cd7b1db01b7ecb525c057c8f6.1681331135.git.jpoimboe@kernel.org
2023-04-14 16:08:29 +02:00
Josh Poimboeuf 6126ed5dfb objtool: Remove superfluous dead_end_function() check
annotate_call_site() already sets 'insn->dead_end' for calls to dead end
functions.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/5d603a301e9a8b1036b61503385907e154867ace.1681325924.git.jpoimboe@kernel.org
2023-04-14 16:08:29 +02:00
Josh Poimboeuf 9290e772ba objtool: Add symbol iteration helpers
Add [sec_]for_each_sym() and use them.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/59023e5886ab125aa30702e633be7732b1acaa7e.1681325924.git.jpoimboe@kernel.org
2023-04-14 16:08:29 +02:00
Josh Poimboeuf 246b2c8548 objtool: Add WARN_INSN()
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
2023-04-14 16:08:28 +02:00
Josh Poimboeuf 7f530fba11 objtool: Add stackleak instrumentation to uaccess safe list
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
2023-04-14 16:08:27 +02:00
Josh Poimboeuf e18398e80c Revert "objtool: Support addition to set CFA base"
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/
2023-04-14 16:08:27 +02:00
Jonathan Corbet ff61f0791c docs: move x86 documentation into Documentation/arch/
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>
2023-03-30 12:58:51 -06:00
Josh Poimboeuf fb799447ae x86,objtool: Split UNWIND_HINT_EMPTY in two
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
2023-03-23 23:18:58 +01:00
Josh Poimboeuf 4708ea14be x86,objtool: Separate unret validation from unwind hints
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
2023-03-23 23:18:58 +01:00
Josh Poimboeuf f902cfdd46 x86,objtool: Introduce ORC_TYPE_*
Unwind hints and ORC entry types are two distinct things.  Separate them
out more explicitly.

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/cc879d38fff8a43f8f7beb2fd56e35a5a384d7cd.1677683419.git.jpoimboe@kernel.org
2023-03-23 23:18:57 +01:00
Josh Poimboeuf f7515d9fe8 objtool: Add objtool_types.h
Reduce the amount of header sync churn by splitting the shared objtool.h
types into a new file.

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/dec622720851210ceafa12d4f4c5f9e73c832152.1677683419.git.jpoimboe@kernel.org
2023-03-23 23:18:56 +01:00
Josh Poimboeuf 071c44e427 sched/idle: Mark arch_cpu_idle_dead() __noreturn
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>
2023-03-08 08:44:28 -08:00
Linus Torvalds 857f1268a5 Changes in this cycle were:
- 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-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmQAVp8RHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1gV6A//YbWb4nNxYbRFBd1O3FnFfy4efrDQ4btI
 hwkL6f7jka9RnIpIEatJvaLdNvyN5tuPCC/+B5eVnvFdd1JcBUmj5D+zYFt6H6qt
 BG4M6TNHFkP1kOJVfFGn8UPRfoMz2oMiEqilpsc1Yuf7b3ldMJtGUoHaeZC9pyqe
 RUisKNw4WHZp2G/gTBUWxW17xpWY3Awgch/w4HCu8wMnR+uEC44i0UCBfnAadl36
 ar66PfhMJcQIv0XkK9wu43g7+HFnjpxHOx35JW3lRot0xRnwl/JcsmaX5iPkh0gt
 HV8eLH80J0homeMZDY7vWIKJxGeLkIdfjO5gxwTdnFc9rQw3GwHp1B7WTS6J3Vwe
 gM00kyaGly3CvkKMiz5QQBfViWCjE25nYS8X0i9Oz6Gk58IkRPGByaDTKRjNrDJB
 BwH9DE9xb3dPVZRv/PejkTdggQWo+FDTrL8ulHIjUFK11M7VubwkskecNHkfpAOE
 TRy5iLjMocF8u7hdyec6Mma2K6qEndC2Rw9ZMPQ7TeieMsBcl63cSRgSJLFfdRhr
 /5c6Hr2SNQKU8xu+3j49GyBwFvp4CwCa+GPs9/o+l0uCvuKNIn9B788cm4TjxLJ9
 C3PRzE6B/CaLhYvlC5k5cNM+I4YpoMU/mvSvY6HcC0Duj2nSAWS2VV60MVMDpqVX
 8nK4xnla2tM=
 =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
  ...
2023-03-02 09:45:34 -08:00
Linus Torvalds 3822a7c409 - 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".
 -----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
  ...
2023-02-23 17:09:35 -08:00
Josh Poimboeuf 00c8f01c4e objtool: Fix ORC 'signal' propagation
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
2023-02-23 09:21:50 +01:00
Peter Zijlstra 1c34496e58 objtool: Remove instruction::list
Replace the instruction::list by allocating instructions in arrays of
256 entries and stringing them together by (amortized) find_insn().
This shrinks instruction by 16 bytes and brings it down to 128.

 struct instruction {
-	struct list_head           list;                 /*     0    16 */
-	struct hlist_node          hash;                 /*    16    16 */
-	struct list_head           call_node;            /*    32    16 */
-	struct section *           sec;                  /*    48     8 */
-	long unsigned int          offset;               /*    56     8 */
-	/* --- cacheline 1 boundary (64 bytes) --- */
-	long unsigned int          immediate;            /*    64     8 */
-	unsigned int               len;                  /*    72     4 */
-	u8                         type;                 /*    76     1 */
-
-	/* Bitfield combined with previous fields */
+	struct hlist_node          hash;                 /*     0    16 */
+	struct list_head           call_node;            /*    16    16 */
+	struct section *           sec;                  /*    32     8 */
+	long unsigned int          offset;               /*    40     8 */
+	long unsigned int          immediate;            /*    48     8 */
+	u8                         len;                  /*    56     1 */
+	u8                         prev_len;             /*    57     1 */
+	u8                         type;                 /*    58     1 */
+	s8                         instr;                /*    59     1 */
+	u32                        idx:8;                /*    60: 0  4 */
+	u32                        dead_end:1;           /*    60: 8  4 */
+	u32                        ignore:1;             /*    60: 9  4 */
+	u32                        ignore_alts:1;        /*    60:10  4 */
+	u32                        hint:1;               /*    60:11  4 */
+	u32                        save:1;               /*    60:12  4 */
+	u32                        restore:1;            /*    60:13  4 */
+	u32                        retpoline_safe:1;     /*    60:14  4 */
+	u32                        noendbr:1;            /*    60:15  4 */
+	u32                        entry:1;              /*    60:16  4 */
+	u32                        visited:4;            /*    60:17  4 */
+	u32                        no_reloc:1;           /*    60:21  4 */

-	u16                        dead_end:1;           /*    76: 8  2 */
-	u16                        ignore:1;             /*    76: 9  2 */
-	u16                        ignore_alts:1;        /*    76:10  2 */
-	u16                        hint:1;               /*    76:11  2 */
-	u16                        save:1;               /*    76:12  2 */
-	u16                        restore:1;            /*    76:13  2 */
-	u16                        retpoline_safe:1;     /*    76:14  2 */
-	u16                        noendbr:1;            /*    76:15  2 */
-	u16                        entry:1;              /*    78: 0  2 */
-	u16                        visited:4;            /*    78: 1  2 */
-	u16                        no_reloc:1;           /*    78: 5  2 */
+	/* XXX 10 bits hole, try to pack */

-	/* XXX 2 bits hole, try to pack */
-	/* Bitfield combined with next fields */
-
-	s8                         instr;                /*    79     1 */
-	struct alt_group *         alt_group;            /*    80     8 */
-	struct instruction *       jump_dest;            /*    88     8 */
-	struct instruction *       first_jump_src;       /*    96     8 */
+	/* --- cacheline 1 boundary (64 bytes) --- */
+	struct alt_group *         alt_group;            /*    64     8 */
+	struct instruction *       jump_dest;            /*    72     8 */
+	struct instruction *       first_jump_src;       /*    80     8 */
 	union {
-		struct symbol *    _call_dest;           /*   104     8 */
-		struct reloc *     _jump_table;          /*   104     8 */
-	};                                               /*   104     8 */
-	struct alternative *       alts;                 /*   112     8 */
-	struct symbol *            sym;                  /*   120     8 */
-	/* --- cacheline 2 boundary (128 bytes) --- */
-	struct stack_op *          stack_ops;            /*   128     8 */
-	struct cfi_state *         cfi;                  /*   136     8 */
+		struct symbol *    _call_dest;           /*    88     8 */
+		struct reloc *     _jump_table;          /*    88     8 */
+	};                                               /*    88     8 */
+	struct alternative *       alts;                 /*    96     8 */
+	struct symbol *            sym;                  /*   104     8 */
+	struct stack_op *          stack_ops;            /*   112     8 */
+	struct cfi_state *         cfi;                  /*   120     8 */

-	/* size: 144, cachelines: 3, members: 28 */
-	/* sum members: 142 */
-	/* sum bitfield members: 14 bits, bit holes: 1, sum bit holes: 2 bits */
-	/* last cacheline: 16 bytes */
+	/* size: 128, cachelines: 2, members: 29 */
+	/* sum members: 124 */
+	/* sum bitfield members: 22 bits, bit holes: 1, sum bit holes: 10 bits */
 };

pre:	5:38.18 real,   213.25 user,    124.90 sys,     23449040 mem
post:	5:03.34 real,   210.75 user,    88.80 sys,      20241232 mem

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/20230208172245.851307606@infradead.org
2023-02-23 09:21:44 +01:00
Peter Zijlstra a706bb08c8 objtool: Fix overlapping alternatives
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
2023-02-23 09:21:33 +01:00
Peter Zijlstra c6f5dc28fb objtool: Union instruction::{call_dest,jump_table}
The instruction call_dest and jump_table members can never be used at
the same time, their usage depends on type.

 struct instruction {
 	struct list_head           list;                 /*     0    16 */
 	struct hlist_node          hash;                 /*    16    16 */
 	struct list_head           call_node;            /*    32    16 */
 	struct section *           sec;                  /*    48     8 */
 	long unsigned int          offset;               /*    56     8 */
 	/* --- cacheline 1 boundary (64 bytes) --- */
 	long unsigned int          immediate;            /*    64     8 */
 	unsigned int               len;                  /*    72     4 */
 	u8                         type;                 /*    76     1 */

 	/* Bitfield combined with previous fields */

 	u16                        dead_end:1;           /*    76: 8  2 */
 	u16                        ignore:1;             /*    76: 9  2 */
 	u16                        ignore_alts:1;        /*    76:10  2 */
 	u16                        hint:1;               /*    76:11  2 */
 	u16                        save:1;               /*    76:12  2 */
 	u16                        restore:1;            /*    76:13  2 */
 	u16                        retpoline_safe:1;     /*    76:14  2 */
 	u16                        noendbr:1;            /*    76:15  2 */
 	u16                        entry:1;              /*    78: 0  2 */
 	u16                        visited:4;            /*    78: 1  2 */
 	u16                        no_reloc:1;           /*    78: 5  2 */

 	/* XXX 2 bits hole, try to pack */
 	/* Bitfield combined with next fields */

 	s8                         instr;                /*    79     1 */
 	struct alt_group *         alt_group;            /*    80     8 */
-	struct symbol *            call_dest;            /*    88     8 */
-	struct instruction *       jump_dest;            /*    96     8 */
-	struct instruction *       first_jump_src;       /*   104     8 */
-	struct reloc *             jump_table;           /*   112     8 */
-	struct alternative *       alts;                 /*   120     8 */
+	struct instruction *       jump_dest;            /*    88     8 */
+	struct instruction *       first_jump_src;       /*    96     8 */
+	union {
+		struct symbol *    _call_dest;           /*   104     8 */
+		struct reloc *     _jump_table;          /*   104     8 */
+	};                                               /*   104     8 */
+	struct alternative *       alts;                 /*   112     8 */
+	struct symbol *            sym;                  /*   120     8 */
 	/* --- cacheline 2 boundary (128 bytes) --- */
-	struct symbol *            sym;                  /*   128     8 */
-	struct stack_op *          stack_ops;            /*   136     8 */
-	struct cfi_state *         cfi;                  /*   144     8 */
+	struct stack_op *          stack_ops;            /*   128     8 */
+	struct cfi_state *         cfi;                  /*   136     8 */

-	/* size: 152, cachelines: 3, members: 29 */
-	/* sum members: 150 */
+	/* size: 144, cachelines: 3, members: 28 */
+	/* sum members: 142 */
 	/* sum bitfield members: 14 bits, bit holes: 1, sum bit holes: 2 bits */
-	/* last cacheline: 24 bytes */
+	/* last cacheline: 16 bytes */
 };

pre:	5:39.35 real,   215.58 user,    123.69 sys,     23448736 mem
post:	5:38.18 real,   213.25 user,    124.90 sys,     23449040 mem

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/20230208172245.640914454@infradead.org
2023-02-23 09:21:27 +01:00
Peter Zijlstra 0932dbe1f5 objtool: Remove instruction::reloc
Instead of caching the reloc for each instruction, only keep a
negative cache of not having a reloc (by far the most common case).

 struct instruction {
 	struct list_head           list;                 /*     0    16 */
 	struct hlist_node          hash;                 /*    16    16 */
 	struct list_head           call_node;            /*    32    16 */
 	struct section *           sec;                  /*    48     8 */
 	long unsigned int          offset;               /*    56     8 */
 	/* --- cacheline 1 boundary (64 bytes) --- */
 	long unsigned int          immediate;            /*    64     8 */
 	unsigned int               len;                  /*    72     4 */
 	u8                         type;                 /*    76     1 */

 	/* Bitfield combined with previous fields */

 	u16                        dead_end:1;           /*    76: 8  2 */
 	u16                        ignore:1;             /*    76: 9  2 */
 	u16                        ignore_alts:1;        /*    76:10  2 */
 	u16                        hint:1;               /*    76:11  2 */
 	u16                        save:1;               /*    76:12  2 */
 	u16                        restore:1;            /*    76:13  2 */
 	u16                        retpoline_safe:1;     /*    76:14  2 */
 	u16                        noendbr:1;            /*    76:15  2 */
 	u16                        entry:1;              /*    78: 0  2 */
 	u16                        visited:4;            /*    78: 1  2 */
+	u16                        no_reloc:1;           /*    78: 5  2 */

-	/* XXX 3 bits hole, try to pack */
+	/* XXX 2 bits hole, try to pack */
 	/* Bitfield combined with next fields */

 	s8                         instr;                /*    79     1 */
 	struct alt_group *         alt_group;            /*    80     8 */
 	struct symbol *            call_dest;            /*    88     8 */
 	struct instruction *       jump_dest;            /*    96     8 */
 	struct instruction *       first_jump_src;       /*   104     8 */
 	struct reloc *             jump_table;           /*   112     8 */
-	struct reloc *             reloc;                /*   120     8 */
+	struct alternative *       alts;                 /*   120     8 */
 	/* --- cacheline 2 boundary (128 bytes) --- */
-	struct alternative *       alts;                 /*   128     8 */
-	struct symbol *            sym;                  /*   136     8 */
-	struct stack_op *          stack_ops;            /*   144     8 */
-	struct cfi_state *         cfi;                  /*   152     8 */
+	struct symbol *            sym;                  /*   128     8 */
+	struct stack_op *          stack_ops;            /*   136     8 */
+	struct cfi_state *         cfi;                  /*   144     8 */

-	/* size: 160, cachelines: 3, members: 29 */
-	/* sum members: 158 */
-	/* sum bitfield members: 13 bits, bit holes: 1, sum bit holes: 3 bits */
-	/* last cacheline: 32 bytes */
+	/* size: 152, cachelines: 3, members: 29 */
+	/* sum members: 150 */
+	/* sum bitfield members: 14 bits, bit holes: 1, sum bit holes: 2 bits */
+	/* last cacheline: 24 bytes */
 };

pre:	5:48.89 real,   220.96 user,    127.55 sys,     24834672 mem
post:	5:39.35 real,   215.58 user,    123.69 sys,     23448736 mem

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/20230208172245.572145269@infradead.org
2023-02-23 09:21:17 +01:00
Peter Zijlstra 8b2de41215 objtool: Shrink instruction::{type,visited}
Since we don't have that many types in enum insn_type, force it into a
u8 and re-arrange member to get rid of the holes, saves another 8
bytes.

 struct instruction {
 	struct list_head           list;                 /*     0    16 */
 	struct hlist_node          hash;                 /*    16    16 */
 	struct list_head           call_node;            /*    32    16 */
 	struct section *           sec;                  /*    48     8 */
 	long unsigned int          offset;               /*    56     8 */
 	/* --- cacheline 1 boundary (64 bytes) --- */
-	unsigned int               len;                  /*    64     4 */
-	enum insn_type             type;                 /*    68     4 */
-	long unsigned int          immediate;            /*    72     8 */
-	u16                        dead_end:1;           /*    80: 0  2 */
-	u16                        ignore:1;             /*    80: 1  2 */
-	u16                        ignore_alts:1;        /*    80: 2  2 */
-	u16                        hint:1;               /*    80: 3  2 */
-	u16                        save:1;               /*    80: 4  2 */
-	u16                        restore:1;            /*    80: 5  2 */
-	u16                        retpoline_safe:1;     /*    80: 6  2 */
-	u16                        noendbr:1;            /*    80: 7  2 */
-	u16                        entry:1;              /*    80: 8  2 */
+	long unsigned int          immediate;            /*    64     8 */
+	unsigned int               len;                  /*    72     4 */
+	u8                         type;                 /*    76     1 */

-	/* XXX 7 bits hole, try to pack */
+	/* Bitfield combined with previous fields */

-	s8                         instr;                /*    82     1 */
-	u8                         visited;              /*    83     1 */
+	u16                        dead_end:1;           /*    76: 8  2 */
+	u16                        ignore:1;             /*    76: 9  2 */
+	u16                        ignore_alts:1;        /*    76:10  2 */
+	u16                        hint:1;               /*    76:11  2 */
+	u16                        save:1;               /*    76:12  2 */
+	u16                        restore:1;            /*    76:13  2 */
+	u16                        retpoline_safe:1;     /*    76:14  2 */
+	u16                        noendbr:1;            /*    76:15  2 */
+	u16                        entry:1;              /*    78: 0  2 */
+	u16                        visited:4;            /*    78: 1  2 */

-	/* XXX 4 bytes hole, try to pack */
+	/* XXX 3 bits hole, try to pack */
+	/* Bitfield combined with next fields */

-	struct alt_group *         alt_group;            /*    88     8 */
-	struct symbol *            call_dest;            /*    96     8 */
-	struct instruction *       jump_dest;            /*   104     8 */
-	struct instruction *       first_jump_src;       /*   112     8 */
-	struct reloc *             jump_table;           /*   120     8 */
+	s8                         instr;                /*    79     1 */
+	struct alt_group *         alt_group;            /*    80     8 */
+	struct symbol *            call_dest;            /*    88     8 */
+	struct instruction *       jump_dest;            /*    96     8 */
+	struct instruction *       first_jump_src;       /*   104     8 */
+	struct reloc *             jump_table;           /*   112     8 */
+	struct reloc *             reloc;                /*   120     8 */
 	/* --- cacheline 2 boundary (128 bytes) --- */
-	struct reloc *             reloc;                /*   128     8 */
-	struct alternative *       alts;                 /*   136     8 */
-	struct symbol *            sym;                  /*   144     8 */
-	struct stack_op *          stack_ops;            /*   152     8 */
-	struct cfi_state *         cfi;                  /*   160     8 */
+	struct alternative *       alts;                 /*   128     8 */
+	struct symbol *            sym;                  /*   136     8 */
+	struct stack_op *          stack_ops;            /*   144     8 */
+	struct cfi_state *         cfi;                  /*   152     8 */

-	/* size: 168, cachelines: 3, members: 29 */
-	/* sum members: 162, holes: 1, sum holes: 4 */
-	/* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 7 bits */
-	/* last cacheline: 40 bytes */
+	/* size: 160, cachelines: 3, members: 29 */
+	/* sum members: 158 */
+	/* sum bitfield members: 13 bits, bit holes: 1, sum bit holes: 3 bits */
+	/* last cacheline: 32 bytes */
 };

pre:	5:48.86 real,   220.30 user,    128.34 sys,     24834672 mem
post:	5:48.89 real,   220.96 user,    127.55 sys,     24834672 mem

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/20230208172245.501847188@infradead.org
2023-02-23 09:21:12 +01:00
Peter Zijlstra d540665461 objtool: Make instruction::alts a single-linked list
struct instruction {
 	struct list_head           list;                 /*     0    16 */
 	struct hlist_node          hash;                 /*    16    16 */
 	struct list_head           call_node;            /*    32    16 */
 	struct section *           sec;                  /*    48     8 */
 	long unsigned int          offset;               /*    56     8 */
 	/* --- cacheline 1 boundary (64 bytes) --- */
 	unsigned int               len;                  /*    64     4 */
 	enum insn_type             type;                 /*    68     4 */
 	long unsigned int          immediate;            /*    72     8 */
 	u16                        dead_end:1;           /*    80: 0  2 */
 	u16                        ignore:1;             /*    80: 1  2 */
 	u16                        ignore_alts:1;        /*    80: 2  2 */
 	u16                        hint:1;               /*    80: 3  2 */
 	u16                        save:1;               /*    80: 4  2 */
 	u16                        restore:1;            /*    80: 5  2 */
 	u16                        retpoline_safe:1;     /*    80: 6  2 */
 	u16                        noendbr:1;            /*    80: 7  2 */
 	u16                        entry:1;              /*    80: 8  2 */

 	/* XXX 7 bits hole, try to pack */

 	s8                         instr;                /*    82     1 */
 	u8                         visited;              /*    83     1 */

 	/* XXX 4 bytes hole, try to pack */

 	struct alt_group *         alt_group;            /*    88     8 */
 	struct symbol *            call_dest;            /*    96     8 */
 	struct instruction *       jump_dest;            /*   104     8 */
 	struct instruction *       first_jump_src;       /*   112     8 */
 	struct reloc *             jump_table;           /*   120     8 */
 	/* --- cacheline 2 boundary (128 bytes) --- */
 	struct reloc *             reloc;                /*   128     8 */
-	struct list_head           alts;                 /*   136    16 */
-	struct symbol *            sym;                  /*   152     8 */
-	struct stack_op *          stack_ops;            /*   160     8 */
-	struct cfi_state *         cfi;                  /*   168     8 */
+	struct alternative *       alts;                 /*   136     8 */
+	struct symbol *            sym;                  /*   144     8 */
+	struct stack_op *          stack_ops;            /*   152     8 */
+	struct cfi_state *         cfi;                  /*   160     8 */

-	/* size: 176, cachelines: 3, members: 29 */
-	/* sum members: 170, holes: 1, sum holes: 4 */
+	/* size: 168, cachelines: 3, members: 29 */
+	/* sum members: 162, holes: 1, sum holes: 4 */
 	/* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 7 bits */
-	/* last cacheline: 48 bytes */
+	/* last cacheline: 40 bytes */
 };

pre:	5:58.50 real,   229.64 user,    128.65 sys,     26221520 mem
post:	5:48.86 real,   220.30 user,    128.34 sys,     24834672 mem

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/20230208172245.430556498@infradead.org
2023-02-23 09:21:06 +01:00
Peter Zijlstra 3ee88df1b0 objtool: Make instruction::stack_ops a single-linked list
struct instruction {
 	struct list_head           list;                 /*     0    16 */
 	struct hlist_node          hash;                 /*    16    16 */
 	struct list_head           call_node;            /*    32    16 */
 	struct section *           sec;                  /*    48     8 */
 	long unsigned int          offset;               /*    56     8 */
 	/* --- cacheline 1 boundary (64 bytes) --- */
 	unsigned int               len;                  /*    64     4 */
 	enum insn_type             type;                 /*    68     4 */
 	long unsigned int          immediate;            /*    72     8 */
 	u16                        dead_end:1;           /*    80: 0  2 */
 	u16                        ignore:1;             /*    80: 1  2 */
 	u16                        ignore_alts:1;        /*    80: 2  2 */
 	u16                        hint:1;               /*    80: 3  2 */
 	u16                        save:1;               /*    80: 4  2 */
 	u16                        restore:1;            /*    80: 5  2 */
 	u16                        retpoline_safe:1;     /*    80: 6  2 */
 	u16                        noendbr:1;            /*    80: 7  2 */
 	u16                        entry:1;              /*    80: 8  2 */

 	/* XXX 7 bits hole, try to pack */

 	s8                         instr;                /*    82     1 */
 	u8                         visited;              /*    83     1 */

 	/* XXX 4 bytes hole, try to pack */

 	struct alt_group *         alt_group;            /*    88     8 */
 	struct symbol *            call_dest;            /*    96     8 */
 	struct instruction *       jump_dest;            /*   104     8 */
 	struct instruction *       first_jump_src;       /*   112     8 */
 	struct reloc *             jump_table;           /*   120     8 */
 	/* --- cacheline 2 boundary (128 bytes) --- */
 	struct reloc *             reloc;                /*   128     8 */
 	struct list_head           alts;                 /*   136    16 */
 	struct symbol *            sym;                  /*   152     8 */
-	struct list_head           stack_ops;            /*   160    16 */
-	struct cfi_state *         cfi;                  /*   176     8 */
+	struct stack_op *          stack_ops;            /*   160     8 */
+	struct cfi_state *         cfi;                  /*   168     8 */

-	/* size: 184, cachelines: 3, members: 29 */
-	/* sum members: 178, holes: 1, sum holes: 4 */
+	/* size: 176, cachelines: 3, members: 29 */
+	/* sum members: 170, holes: 1, sum holes: 4 */
 	/* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 7 bits */
-	/* last cacheline: 56 bytes */
+	/* last cacheline: 48 bytes */
 };

pre:	5:58.22 real,   226.69 user,    131.22 sys,     26221520 mem
post:	5:58.50 real,   229.64 user,    128.65 sys,     26221520 mem

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/20230208172245.362196959@infradead.org
2023-02-23 09:20:59 +01:00
Peter Zijlstra 20a554638d objtool: Change arch_decode_instruction() signature
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
2023-02-23 09:20:50 +01:00
Ingo Molnar 585a78c1f7 Merge branch 'linus' into objtool/core, to pick up Xen dependencies
Pick up dependencies - freshly merged upstream via xen-next - before applying
dependent objtool changes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2023-02-23 09:16:39 +01:00
Linus Torvalds 239451e903 xen: branch for v6.3-rc1
-----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
2023-02-21 17:07:39 -08:00
Linus Torvalds 1adce1b944 - 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
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmPzkAcACgkQEsHwGGHe
 VUpA3A//bALDnLosUQe/m8CTcj1AU12Y59fGInoLl5xArM3liOhRYWj9yu8+2r5N
 j+89yjWoiaogu/9B18pV0+VnBrFUbALZmHxec0+4VAWyMqYuTbqN28Nj/2cZiHdP
 I/9mwGu40I/Ira021D132EcdoZI7O/6bFlh+kEoAqxc7rsqhD5KKRMlrTTdEPVjH
 aRbWIuzqDWNhbi7IwfgEBIPLiQZQKmIdH5hsFMD6yOMIdMRL6CwKmXVg2M1Zp8ta
 5v2Aqgvu2nZYCIteP4GQck2AlUBlGR4ClGQQRII+U1o8c9dM0hfcIDgsbSYKvgrY
 ANm9MQJaF7MRomk9y4E0EHPZAJEMLKUgiQXMxWpER3O1GOKgZPlyzNSe0gRCiL6O
 NZWZ2cGtdhQMrko4EapE3GNryM1HoCY/QCuD1fCYwoc/pRBDhCxsSqjWUd8G/6wn
 s3S/mD0v3nmTrxHg8sWvqhKshsd7B9V0LSkTpHktz3soFIJGXTxbrtty0CIS61pM
 4iUMYB9SjunoEmdwC7+gCN3sCiRpRqfmIybqXdsW3d37QI+FM5aSBPw51xULubfY
 Wsxo8SkH+IMYxXmfbQuUppsGZ+1QHzU08+MrlvNxGHUjS1aMnsrFF/fbfbbCnWvX
 7hcyBPT0jxc9RPMNeKDm4ItapMMGxGdv6XiRmM8LiUtVG2fMaW4=
 =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
2023-02-21 08:27:47 -08:00
Arnd Bergmann d5d4692472 objtool: add UACCESS exceptions for __tsan_volatile_read/write
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>
2023-02-20 12:46:16 -08:00
Juergen Gross f697cb00af x86/xen: mark xen_pv_play_dead() as __noreturn
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>
2023-02-13 06:53:19 +01:00
Josh Poimboeuf ffb1b4a410 x86/unwind/orc: Add 'signal' field to ORC metadata
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
2023-02-11 12:37:51 +01:00
Peter Zijlstra 443ed4c302 objtool: mem*() are not uaccess safe
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
2023-02-11 11:18:08 +01:00