linux/arch
Linus Torvalds 2bb69f5fc7 x86 mitigations for the native BHI hardware vulnerabilty:
Branch History Injection (BHI) attacks may allow a malicious application to
 influence indirect branch prediction in kernel by poisoning the branch
 history. eIBRS isolates indirect branch targets in ring0.  The BHB can
 still influence the choice of indirect branch predictor entry, and although
 branch predictor entries are isolated between modes when eIBRS is enabled,
 the BHB itself is not isolated between modes.
 
 Add mitigations against it either with the help of microcode or with
 software sequences for the affected CPUs.
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Merge tag 'nativebhi' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mitigations from Thomas Gleixner:
 "Mitigations for the native BHI hardware vulnerabilty:

  Branch History Injection (BHI) attacks may allow a malicious
  application to influence indirect branch prediction in kernel by
  poisoning the branch history. eIBRS isolates indirect branch targets
  in ring0. The BHB can still influence the choice of indirect branch
  predictor entry, and although branch predictor entries are isolated
  between modes when eIBRS is enabled, the BHB itself is not isolated
  between modes.

  Add mitigations against it either with the help of microcode or with
  software sequences for the affected CPUs"

[ This also ends up enabling the full mitigation by default despite the
  system call hardening, because apparently there are other indirect
  calls that are still sufficiently reachable, and the 'auto' case just
  isn't hardened enough.

  We'll have some more inevitable tweaking in the future    - Linus ]

* tag 'nativebhi' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  KVM: x86: Add BHI_NO
  x86/bhi: Mitigate KVM by default
  x86/bhi: Add BHI mitigation knob
  x86/bhi: Enumerate Branch History Injection (BHI) bug
  x86/bhi: Define SPEC_CTRL_BHI_DIS_S
  x86/bhi: Add support for clearing branch history at syscall entry
  x86/syscall: Don't force use of indirect calls for system calls
  x86/bugs: Change commas to semicolons in 'spectre_v2' sysfs file
2024-04-08 20:07:51 -07:00
..
alpha Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
arc - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
arm ARM: prctl: reject PR_SET_MDWE on pre-ARMv6 2024-03-26 11:07:22 -07:00
arm64 arm64/ptrace fix to use the correct SVE layout based on the saved 2024-04-05 13:12:35 -07:00
csky - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
hexagon hexagon: vmlinux.lds.S: handle attributes section 2024-03-26 11:07:23 -07:00
loongarch LoongArch changes for v6.9 2024-03-22 10:22:45 -07:00
m68k TTY/Serial driver update for 6.9-rc1 2024-03-21 12:44:10 -07:00
microblaze arch: define CONFIG_PAGE_SIZE_*KB on all architectures 2024-03-06 19:29:09 +01:00
mips MIPS: move unselectable FIT_IMAGE_FDT_EPM5 out of the "System type" choice 2024-03-27 01:58:34 +09:00
nios2 nios2: Only use built-in devicetree blob if configured to do so 2024-04-03 14:35:53 -05:00
openrisc OpenRISC updates for 6.9 2024-03-14 15:53:10 -07:00
parisc prctl: generalize PR_SET_MDWE support check to be per-arch 2024-03-26 11:07:22 -07:00
powerpc vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.h 2024-04-03 21:50:04 +02:00
riscv RISC-V Fixes for 6.9-rc3 2024-04-05 13:09:48 -07:00
s390 s390/entry: align system call table on 8 bytes 2024-04-03 15:00:20 +02:00
sh sh updates for v6.9 2024-03-21 10:13:47 -07:00
sparc This includes the following changes related to sparc for v6.9: 2024-03-15 12:47:21 -07:00
um Devicetree updates for v6.9: 2024-03-15 12:37:59 -07:00
x86 x86 mitigations for the native BHI hardware vulnerabilty: 2024-04-08 20:07:51 -07:00
xtensa - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
.gitignore
Kconfig hardening fixes for v6.9-rc1 2024-03-23 08:43:21 -07:00