kernel/linux.git/include/linux/objtool.h, branch v6.12.80

x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO

2024-01-10T09:52:29+00:00

Step 9/10 of the namespace unification of CPU mitigations related Kconfig options. Suggested-by: Josh Poimboeuf Signed-off-by: Breno Leitao Signed-off-by: Ingo Molnar Acked-by: Josh Poimboeuf Cc: Linus Torvalds Link: https://lore.kernel.org/r/20231121160740.1249350-10-leitao@debian.org

x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY

2024-01-10T09:52:28+00:00

Step 7/10 of the namespace unification of CPU mitigations related Kconfig options. Suggested-by: Josh Poimboeuf Signed-off-by: Breno Leitao Signed-off-by: Ingo Molnar Acked-by: Josh Poimboeuf Cc: Linus Torvalds Link: https://lore.kernel.org/r/20231121160740.1249350-8-leitao@debian.org

Merge tag 'objtool-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-10-30T23:20:02+00:00

Pull objtool updates from Ingo Molnar: "Misc fixes and cleanups: - Fix potential MAX_NAME_LEN limit related build failures - Fix scripts/faddr2line symbol filtering bug - Fix scripts/faddr2line on LLVM=1 - Fix scripts/faddr2line to accept readelf output with mapping symbols - Minor cleanups" * tag 'objtool-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: scripts/faddr2line: Skip over mapping symbols in output from readelf scripts/faddr2line: Use LLVM addr2line and readelf if LLVM=1 scripts/faddr2line: Don't filter out non-function symbols from readelf objtool: Remove max symbol name length limitation objtool: Propagate early errors objtool: Use 'the fallthrough' pseudo-keyword x86/speculation, objtool: Use absolute relocations for annotations x86/unwind/orc: Remove redundant initialization of 'mid' pointer in __orc_find()

x86/srso: Fix unret validation dependencies

2023-10-20T09:46:59+00:00

CONFIG_CPU_SRSO isn't dependent on CONFIG_CPU_UNRET_ENTRY (AMD Retbleed), so the two features are independently configurable. Fix several issues for the (presumably rare) case where CONFIG_CPU_SRSO is enabled but CONFIG_CPU_UNRET_ENTRY isn't. Fixes: fb3bd914b3ec ("x86/srso: Add a Speculative RAS Overflow mitigation") Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Signed-off-by: Borislav Petkov (AMD) Acked-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/299fb7740174d0f2335e91c58af0e9c242b4bac1.1693889988.git.jpoimboe@kernel.org

x86/speculation, objtool: Use absolute relocations for annotations

2023-09-22T09:41:24+00:00

.discard.retpoline_safe sections do not have the SHF_ALLOC flag. These sections referencing text sections' STT_SECTION symbols with PC-relative relocations like R_386_PC32 [0] is conceptually not suitable. Newer LLD will report warnings for REL relocations even for relocatable links [1]: ld.lld: warning: vmlinux.a(drivers/i2c/busses/i2c-i801.o):(.discard.retpoline_safe+0x120): has non-ABS relocation R_386_PC32 against symbol '' Switch to absolute relocations instead, which indicate link-time addresses. In a relocatable link, these addresses are also output section offsets, used by checks in tools/objtool/check.c. When linking vmlinux, these .discard.* sections will be discarded, therefore it is not a problem that R_X86_64_32 cannot represent a kernel address. Alternatively, we could set the SHF_ALLOC flag for .discard.* sections, but I think non-SHF_ALLOC for sections to be discarded makes more sense. Note: if we decide to never support REL architectures (e.g. arm, i386), we can utilize R_*_NONE relocations (.reloc ., BFD_RELOC_NONE, sym), making .discard.* sections zero-sized. That said, the section content waste is 4 bytes per entry, much smaller than sizeof(Elf{32,64}_Rel). [0] commit 1c0c1faf5692 ("objtool: Use relative pointers for annotations") [1] https://github.com/ClangBuiltLinux/linux/issues/1937 Signed-off-by: Fangrui Song Signed-off-by: Ingo Molnar Acked-by: Peter Zijlstra (Intel) Cc: Josh Poimboeuf Link: https://lore.kernel.org/r/20230920001728.1439947-1-maskray@google.com

x86,objtool: Split UNWIND_HINT_EMPTY in two

2023-03-23T22:18:58+00:00

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 Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Steven Rostedt (Google) Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/fd6212c8b450d3564b855e1cb48404d6277b4d9f.1677683419.git.jpoimboe@kernel.org

x86,objtool: Separate unret validation from unwind hints

2023-03-23T22:18:58+00:00

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 Signed-off-by: Peter Zijlstra (Intel) Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/ff7448d492ea21b86d8a90264b105fbd0d751077.1677683419.git.jpoimboe@kernel.org

objtool: Change UNWIND_HINT() argument order

2023-03-23T22:18:57+00:00

The most important argument is 'type', make that one first. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/d994f8c29376c5618c75698df28fc03b52d3a868.1677683419.git.jpoimboe@kernel.org

objtool: Use relative pointers for annotations

2023-03-23T22:18:56+00:00

They produce the needed relocations while using half the space. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/bed05c64e28200220c9b1754a2f3ce71f73076ea.1677683419.git.jpoimboe@kernel.org

objtool: Add objtool_types.h

2023-03-23T22:18:56+00:00

Reduce the amount of header sync churn by splitting the shared objtool.h types into a new file. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/dec622720851210ceafa12d4f4c5f9e73c832152.1677683419.git.jpoimboe@kernel.org