This name is actively confusing as well, because the simple text_poke*()
APIs use MM-switching based code patching, while text_poke_queue()
is part of the INT3 based text_poke_int3_*() machinery that is an
additional layer of functionality on top of regular text_poke*() functionality.
Rename it to smp_text_poke_batch_add() to make it clear which layer
it belongs to.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-17-mingo@kernel.org
This name is actively confusing as well, because the simple text_poke*()
APIs use MM-switching based code patching, while text_poke_finish()
is part of the INT3 based text_poke_int3_*() machinery that is an
additional layer of functionality on top of regular text_poke*() functionality.
Rename it to smp_text_poke_batch_finish() to make it clear which layer
it belongs to.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-16-mingo@kernel.org
Instead of optimizing NOPs in-place, use a temporary buffer like the
usual alternatives patching flow does. This obviates the need to grab
locks when patching, see
6778977590da ("x86/alternatives: Disable interrupts and sync when optimizing NOPs in place")
While at it, add nomenclature definitions clarifying and simplifying the
naming of function-local variables in the alternatives code.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240130105941.19707-2-bp@alien8.de
Contrary to alternatives, relocations are currently not supported in
call thunk templates. Re-use the existing infrastructure from
alternative.c to allow %rip-relative relocations when copying call
thunk template from its storage location.
The patch allows unification of ASM_INCREMENT_CALL_DEPTH, which already
uses PER_CPU_VAR macro, with INCREMENT_CALL_DEPTH, used in call thunk
template, which is currently limited to use absolute address.
Reuse existing relocation infrastructure from alternative.c.,
as suggested by Peter Zijlstra.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20231105213731.1878100-3-ubizjak@gmail.com
Pull x86 CET-IBT (Control-Flow-Integrity) support from Peter Zijlstra:
"Add support for Intel CET-IBT, available since Tigerlake (11th gen),
which is a coarse grained, hardware based, forward edge
Control-Flow-Integrity mechanism where any indirect CALL/JMP must
target an ENDBR instruction or suffer #CP.
Additionally, since Alderlake (12th gen)/Sapphire-Rapids, speculation
is limited to 2 instructions (and typically fewer) on branch targets
not starting with ENDBR. CET-IBT also limits speculation of the next
sequential instruction after the indirect CALL/JMP [1].
CET-IBT is fundamentally incompatible with retpolines, but provides,
as described above, speculation limits itself"
[1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html
* tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
kvm/emulate: Fix SETcc emulation for ENDBR
x86/Kconfig: Only allow CONFIG_X86_KERNEL_IBT with ld.lld >= 14.0.0
x86/Kconfig: Only enable CONFIG_CC_HAS_IBT for clang >= 14.0.0
kbuild: Fixup the IBT kbuild changes
x86/Kconfig: Do not allow CONFIG_X86_X32_ABI=y with llvm-objcopy
x86: Remove toolchain check for X32 ABI capability
x86/alternative: Use .ibt_endbr_seal to seal indirect calls
objtool: Find unused ENDBR instructions
objtool: Validate IBT assumptions
objtool: Add IBT/ENDBR decoding
objtool: Read the NOENDBR annotation
x86: Annotate idtentry_df()
x86,objtool: Move the ASM_REACHABLE annotation to objtool.h
x86: Annotate call_on_stack()
objtool: Rework ASM_REACHABLE
x86: Mark __invalid_creds() __noreturn
exit: Mark do_group_exit() __noreturn
x86: Mark stop_this_cpu() __noreturn
objtool: Ignore extra-symbol code
objtool: Rename --duplicate to --lto
...