kernel/linux.git/arch/x86/include/asm/text-patching.h, branch v6.12.80

x86/alternatives: Use a temporary buffer when optimizing NOPs

2024-04-09T16:08:11+00:00

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) Link: https://lore.kernel.org/r/20240130105941.19707-2-bp@alien8.de

Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch

2024-02-14T09:45:07+00:00

Conflicts: arch/x86/include/asm/percpu.h arch/x86/include/asm/text-patching.h Signed-off-by: Ingo Molnar

x86/paravirt: Remove no longer needed paravirt patching code

2023-12-10T22:34:37+00:00

Now that paravirt is using the alternatives patching infrastructure, remove the paravirt patching code. Signed-off-by: Juergen Gross Signed-off-by: Borislav Petkov (AMD) Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20231210062138.2417-6-jgross@suse.com

x86/callthunks: Mark apply_relocation() as __init_or_module

2023-11-30T19:15:51+00:00

Do it like the rest of the methods using it. Signed-off-by: Ingo Molnar Cc: Uros Bizjak Link: https://lore.kernel.org/r/20231105213731.1878100-3-ubizjak@gmail.com

x86/callthunks: Handle %rip-relative relocations in call thunk template

2023-11-30T19:06:17+00:00

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 Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20231105213731.1878100-3-ubizjak@gmail.com

x86/alternatives: Introduce int3_emulate_jcc()

2023-01-31T14:05:30+00:00

Move the kprobe Jcc emulation into int3_emulate_jcc() so it can be used by more code -- specifically static_call() will need this. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Reviewed-by: Masami Hiramatsu (Google) Link: https://lore.kernel.org/r/20230123210607.057678245@infradead.org

x86/alternatives: Provide text_poke_copy_locked()

2022-10-17T14:41:11+00:00

The upcoming call thunk patching must hold text_mutex and needs access to text_poke_copy(), which takes text_mutex. Provide a _locked postfixed variant to expose the inner workings. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20220915111147.159977224@infradead.org

x86/alternative: Introduce text_poke_set

2022-05-23T21:07:38+00:00

Introduce a memset like API for text_poke. This will be used to fill the unused RX memory with illegal instructions. Suggested-by: Peter Zijlstra (Intel) Signed-off-by: Song Liu Signed-off-by: Daniel Borkmann Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/bpf/20220520235758.1858153-3-song@kernel.org

Merge tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-03-27T17:17:23+00:00

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 ...

x86/ibt,paravirt: Use text_gen_insn() for paravirt_patch()

2022-03-15T09:32:34+00:00

Less duplication is more better. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154317.697253958@infradead.org