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Linus Torvalds bf98bae3d8 - Use LEA ...%rsp instead of ADD %rsp in the Zen1/2 SRSO return sequence
as latter clobbers flags which interferes with fastop emulation in
   KVM, leading to guests freezing during boot
 
 - A fix for the DIV(0) quotient data leak on Zen1 to clear the divider
   buffers at the right time
 
 - Disable the SRSO mitigation on unaffected configurations as it got
   enabled there unnecessarily
 
 - Change .text section name to fix CONFIG_LTO_CLANG builds
 
 - Improve the optprobe indirect jmp check so that certain configurations
   can still be able to use optprobes at all
 
 - A serious and good scrubbing of the untraining routines by PeterZ:
  - Add proper speculation stopping traps so that objtool is happy
  - Adjust objtool to handle the new thunks
  - Make the thunk pointer assignable to the different untraining
    sequences at runtime, thus avoiding the alternative at the return
    thunk. It simplifies the code a bit too.
  - Add a entry_untrain_ret() main entry point which selects the
    respective untraining sequence
  - Rename things so that they're more clear
  - Fix stack validation with FRAME_POINTER=y builds
 
 - Fix static call patching to handle when a JMP to the return thunk is
   the last insn on the very last module memory page
 
 - Add more documentation about what each untraining routine does and
   why
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Merge tag 'x86_urgent_for_v6.5_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:
 "Extraordinary embargoed times call for extraordinary measures. That's
  why this week's x86/urgent branch is larger than usual, containing all
  the known fallout fixes after the SRSO mitigation got merged.

  I know, it is a bit late in the game but everyone who has reported a
  bug stemming from the SRSO pile, has tested that branch and has
  confirmed that it fixes their bug.

  Also, I've run it on every possible hardware I have and it is looking
  good. It is running on this very machine while I'm typing, for 2 days
  now without an issue. Famous last words...

   - Use LEA ...%rsp instead of ADD %rsp in the Zen1/2 SRSO return
     sequence as latter clobbers flags which interferes with fastop
     emulation in KVM, leading to guests freezing during boot

   - A fix for the DIV(0) quotient data leak on Zen1 to clear the
     divider buffers at the right time

   - Disable the SRSO mitigation on unaffected configurations as it got
     enabled there unnecessarily

   - Change .text section name to fix CONFIG_LTO_CLANG builds

   - Improve the optprobe indirect jmp check so that certain
     configurations can still be able to use optprobes at all

   - A serious and good scrubbing of the untraining routines by PeterZ:
      - Add proper speculation stopping traps so that objtool is happy
      - Adjust objtool to handle the new thunks
      - Make the thunk pointer assignable to the different untraining
        sequences at runtime, thus avoiding the alternative at the
        return thunk. It simplifies the code a bit too.
      - Add a entry_untrain_ret() main entry point which selects the
        respective untraining sequence
      - Rename things so that they're more clear
      - Fix stack validation with FRAME_POINTER=y builds

   - Fix static call patching to handle when a JMP to the return thunk
     is the last insn on the very last module memory page

   - Add more documentation about what each untraining routine does and
     why"

* tag 'x86_urgent_for_v6.5_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/srso: Correct the mitigation status when SMT is disabled
  x86/static_call: Fix __static_call_fixup()
  objtool/x86: Fixup frame-pointer vs rethunk
  x86/srso: Explain the untraining sequences a bit more
  x86/cpu/kvm: Provide UNTRAIN_RET_VM
  x86/cpu: Cleanup the untrain mess
  x86/cpu: Rename srso_(.*)_alias to srso_alias_\1
  x86/cpu: Rename original retbleed methods
  x86/cpu: Clean up SRSO return thunk mess
  x86/alternative: Make custom return thunk unconditional
  objtool/x86: Fix SRSO mess
  x86/cpu: Fix up srso_safe_ret() and __x86_return_thunk()
  x86/cpu: Fix __x86_return_thunk symbol type
  x86/retpoline,kprobes: Skip optprobe check for indirect jumps with retpolines and IBT
  x86/retpoline,kprobes: Fix position of thunk sections with CONFIG_LTO_CLANG
  x86/srso: Disable the mitigation on unaffected configurations
  x86/CPU/AMD: Fix the DIV(0) initial fix attempt
  x86/retpoline: Don't clobber RFLAGS during srso_safe_ret()
2023-08-19 10:46:02 +02:00
arch - Use LEA ...%rsp instead of ADD %rsp in the Zen1/2 SRSO return sequence 2023-08-19 10:46:02 +02:00
block block-6.5-2023-08-11 2023-08-11 12:14:08 -07:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto crypto: algif_hash - Fix race between MORE and non-MORE sends 2023-07-08 22:48:42 +10:00
Documentation - Use LEA ...%rsp instead of ADD %rsp in the Zen1/2 SRSO return sequence 2023-08-19 10:46:02 +02:00
drivers gpio fixes for v6.5-rc6 2023-08-18 20:36:49 +02:00
fs smb: client: fix null auth 2023-08-16 00:26:07 -05:00
include Including fixes from ipsec and netfilter. 2023-08-18 06:52:23 +02:00
init Kbuild updates for v6.5 2023-07-01 09:24:31 -07:00
io_uring io_uring/parisc: Adjust pgoff in io_uring mmap() for parisc 2023-08-08 12:37:01 -06:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel Power management fixes for 6.5-rc6 2023-08-11 12:24:22 -07:00
lib 14 hotfixes. 11 of these are cc:stable and the remainder address post-6.4 2023-08-11 14:19:20 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 14 hotfixes. 11 of these are cc:stable and the remainder address post-6.4 2023-08-11 14:19:20 -07:00
net Including fixes from ipsec and netfilter. 2023-08-18 06:52:23 +02:00
rust rust: fix bindgen build error with UBSAN_BOUNDS_STRICT 2023-08-04 17:10:50 +02:00
samples arm64: ftrace: Add direct call trampoline samples support 2023-07-10 17:51:54 -04:00
scripts Kbuild fixes for v6.5 (2nd) 2023-08-13 08:56:24 -07:00
security sysctl: set variable key_sysctls storage-class-specifier to static 2023-08-07 17:55:54 +00:00
sound ALSA: hda/realtek - Remodified 3k pull low procedure 2023-08-16 14:20:27 +02:00
tools - Use LEA ...%rsp instead of ADD %rsp in the Zen1/2 SRSO return sequence 2023-08-19 10:46:02 +02:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt KVM: Grab a reference to KVM for VM and vCPU stats file descriptors 2023-07-29 11:05:28 -04:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Revert ".gitignore: ignore *.cover and *.mbx" 2023-07-04 15:05:12 -07:00
.mailmap mailmap: add entries for Simon Horman 2023-08-16 09:53:10 +01:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS - Address -Wmissing-prototype warnings 2023-06-26 16:43:54 -07:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS gpio fixes for v6.5-rc6 2023-08-18 20:36:49 +02:00
Makefile Linux 6.5-rc6 2023-08-13 11:29:55 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.