objtool/rust: add one more `noreturn` Rust function for Rust 1.87.0

Starting with Rust 1.87.0 (expected 2025-05-15), `objtool` may report:

rust/core.o: warning: objtool: _R..._4core9panicking9p

objtool/rust: add one more `noreturn` Rust function for Rust 1.87.0

Starting with Rust 1.87.0 (expected 2025-05-15), `objtool` may report:

rust/core.o: warning: objtool: _R..._4core9panicking9panic_fmt() falls
through to next function _R..._4core9panicking18panic_nounwind_fmt()

rust/core.o: warning: objtool: _R..._4core9panicking18panic_nounwind_fmt()
falls through to next function _R..._4core9panicking5panic()

The reason is that `rust_begin_unwind` is now mangled:

_R..._7___rustc17rust_begin_unwind

Thus add the mangled one to the list so that `objtool` knows it is
actually `noreturn`.

See commit 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
for more details.

Alternatively, we could remove the fixed one in `noreturn.h` and relax
this test to cover both, but it seems best to be strict as long as we can.

Cc: [email protected] # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Cc: Josh Poimboeuf <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

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objtool/rust: add one more `noreturn` Rust function for Rust 1.86.0

Starting with Rust 1.86.0 (see upstream commit b151b513ba2b ("Insert null
checks for pointer dereferences when debug assertions ar

objtool/rust: add one more `noreturn` Rust function for Rust 1.86.0

Starting with Rust 1.86.0 (see upstream commit b151b513ba2b ("Insert null
checks for pointer dereferences when debug assertions are enabled") [1]),
under some kernel configurations with `CONFIG_RUST_DEBUG_ASSERTIONS=y`,
one may trigger a new `objtool` warning:

rust/kernel.o: warning: objtool: _R..._6kernel9workqueue6system()
falls through to next function _R...9workqueue14system_highpri()

due to a call to the `noreturn` symbol:

core::panicking::panic_null_pointer_dereference

Thus add it to the list so that `objtool` knows it is actually `noreturn`.

See commit 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
for more details.

Cc: [email protected] # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Fixes: 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
Link: https://github.com/rust-lang/rust/commit/b151b513ba2b65c7506ec1a80f2712bbd09154d1 [1]
Reviewed-by: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

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objtool: Remove ANNOTATE_IGNORE_ALTERNATIVE from CLAC/STAC

ANNOTATE_IGNORE_ALTERNATIVE adds additional noise to the code generated
by CLAC/STAC alternatives, hurting readability for those whose read

objtool: Remove ANNOTATE_IGNORE_ALTERNATIVE from CLAC/STAC

ANNOTATE_IGNORE_ALTERNATIVE adds additional noise to the code generated
by CLAC/STAC alternatives, hurting readability for those whose read
uaccess-related code generation on a regular basis.

Remove the annotation specifically for the "NOP patched with CLAC/STAC"
case in favor of a manual check.

Leave the other uses of that annotation in place as they're less common
and more difficult to detect.

Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Acked-by: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/fc972ba4995d826fcfb8d02733a14be8d670900b.1744098446.git.jpoimboe@kernel.org

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objtool, xen: Fix INSN_SYSCALL / INSN_SYSRET semantics

Objtool uses an arbitrary rule for INSN_SYSCALL and INSN_SYSRET that
almost works by accident: if it's in a function, control flow continues
af

objtool, xen: Fix INSN_SYSCALL / INSN_SYSRET semantics

Objtool uses an arbitrary rule for INSN_SYSCALL and INSN_SYSRET that
almost works by accident: if it's in a function, control flow continues
after the instruction, otherwise it terminates.

That behavior should instead be based on the semantics of the underlying
instruction. Change INSN_SYSCALL to always preserve control flow and
INSN_SYSRET to always terminate it.

The changed semantic for INSN_SYSCALL requires a tweak to the
!CONFIG_IA32_EMULATION version of xen_entry_SYSCALL_compat(). In Xen,
SYSCALL is a hypercall which usually returns. But in this case it's a
hypercall to IRET which doesn't return. Add UD2 to tell objtool to
terminate control flow, and to prevent undefined behavior at runtime.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Reviewed-by: Juergen Gross <[email protected]> # for the Xen part
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/19453dfe9a0431b7f016e9dc16d031cad3812a50.1744095216.git.jpoimboe@kernel.org

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objtool: Stop UNRET validation on UD2

In preparation for simplifying INSN_SYSCALL, make validate_unret()
terminate control flow on UD2 just like validate_branch() already does.

Signed-off-by: Josh

objtool: Stop UNRET validation on UD2

In preparation for simplifying INSN_SYSCALL, make validate_unret()
terminate control flow on UD2 just like validate_branch() already does.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/ce841269e7e28c8b7f32064464a9821034d724ff.1744095216.git.jpoimboe@kernel.org

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objtool: Split INSN_CONTEXT_SWITCH into INSN_SYSCALL and INSN_SYSRET

INSN_CONTEXT_SWITCH is ambiguous. It can represent both call semantics
(SYSCALL, SYSENTER) and return semantics (SYSRET, IRET, R

objtool: Split INSN_CONTEXT_SWITCH into INSN_SYSCALL and INSN_SYSRET

INSN_CONTEXT_SWITCH is ambiguous. It can represent both call semantics
(SYSCALL, SYSENTER) and return semantics (SYSRET, IRET, RETS, RETU).
Those differ significantly: calls preserve control flow whereas returns
terminate it.

Objtool uses an arbitrary rule for INSN_CONTEXT_SWITCH that almost works
by accident: if in a function, keep going; otherwise stop. It should
instead be based on the semantics of the underlying instruction.

In preparation for improving that, split INSN_CONTEXT_SWITCH into
INSN_SYCALL and INSN_SYSRET.

No functional change.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/19a76c74d2c051d3bc9a775823cafc65ad267a7a.1744095216.git.jpoimboe@kernel.org

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objtool: Fix INSN_CONTEXT_SWITCH handling in validate_unret()

The !CONFIG_IA32_EMULATION version of xen_entry_SYSCALL_compat() ends
with a SYSCALL instruction which is classified by objtool as
INSN_

objtool: Fix INSN_CONTEXT_SWITCH handling in validate_unret()

The !CONFIG_IA32_EMULATION version of xen_entry_SYSCALL_compat() ends
with a SYSCALL instruction which is classified by objtool as
INSN_CONTEXT_SWITCH.

Unlike validate_branch(), validate_unret() doesn't consider
INSN_CONTEXT_SWITCH in a non-function to be a dead end, so it keeps
going past the end of xen_entry_SYSCALL_compat(), resulting in the
following warning:

vmlinux.o: warning: objtool: xen_reschedule_interrupt+0x2a: RET before UNTRAIN

Fix that by adding INSN_CONTEXT_SWITCH handling to validate_unret() to
match what validate_branch() is already doing.

Fixes: a09a6e2399ba ("objtool: Add entry UNRET validation")
Reported-by: Andrew Cooper <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/f5eda46fd09f15b1f5cde3d9ae3b92b958342add.1744095216.git.jpoimboe@kernel.org

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objtool: Fix verbose disassembly if CROSS_COMPILE isn't set

In verbose mode, when printing the disassembly of affected functions, if
CROSS_COMPILE isn't set, the objdump command string gets prefixed

objtool: Fix verbose disassembly if CROSS_COMPILE isn't set

In verbose mode, when printing the disassembly of affected functions, if
CROSS_COMPILE isn't set, the objdump command string gets prefixed with
"(null)".

Somehow this worked before. Maybe some versions of glibc return an
empty string instead of NULL. Fix it regardless.

[ jpoimboe: Rewrite commit log. ]

Fixes: ca653464dd097 ("objtool: Add verbose option for disassembling affected functions")
Signed-off-by: David Laight <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Link: https://lore.kernel.org/r/b931a4786bc0127aa4c94e8b35ed617dcbd3d3da.1743481539.git.jpoimboe@kernel.org

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objtool: Change "warning:" to "error: " for fatal errors

This is similar to GCC's behavior and makes it more obvious why the
build failed.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed

objtool: Change "warning:" to "error: " for fatal errors

This is similar to GCC's behavior and makes it more obvious why the
build failed.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/0ea76f4b0e7a370711ed9f75fd0792bb5979c2bf.1743481539.git.jpoimboe@kernel.org

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objtool: Always fail on fatal errors

Objtool writes several object annotations which are used to enable
critical kernel runtime functionalities like static calls and
retpoline/rethunk patching.

In

objtool: Always fail on fatal errors

Objtool writes several object annotations which are used to enable
critical kernel runtime functionalities like static calls and
retpoline/rethunk patching.

In the rare case where it fails to read or write an object, the
annotations don't get written, causing runtime code patching to fail and
code to become corrupted.

Due to the catastrophic nature of such warnings, convert them to errors
which fail the build regardless of CONFIG_OBJTOOL_WERROR.

Reported-by: Chaitanya Kumar Borah <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/7d35684ca61eac56eb2424f300ca43c5d257b170.1743481539.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/SJ1PR11MB61295789E25C2F5197EFF2F6B9A72@SJ1PR11MB6129.namprd11.prod.outlook.com

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Revert "objtool: Increase per-function WARN_FUNC() rate limit"

This reverts commit 0a7fb6f07e3ad497d31ae9a2082d2cacab43d54a.

The "skipping duplicate warnings" warning is technically not an actual
w

Revert "objtool: Increase per-function WARN_FUNC() rate limit"

This reverts commit 0a7fb6f07e3ad497d31ae9a2082d2cacab43d54a.

The "skipping duplicate warnings" warning is technically not an actual
warning, which can cause confusion. This feature isn't all that useful
anyway. It's exceedingly rare for a function to have more than one
unrelated warning.

Suggested-by: Ingo Molnar <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/e5abe5e858acf1a9207a5dfa0f37d17ac9dca872.1743481539.git.jpoimboe@kernel.org

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objtool: Append "()" to function name in "unexpected end of section" warning

Append with "()" to clarify it's a function.

Before:

vmlinux.o: warning: objtool: cdns_mrvl_xspi_setup_clock: unexpec

objtool: Append "()" to function name in "unexpected end of section" warning

Append with "()" to clarify it's a function.

Before:

vmlinux.o: warning: objtool: cdns_mrvl_xspi_setup_clock: unexpected end of section .text.cdns_mrvl_xspi_setup_clock

After:

vmlinux.o: warning: objtool: cdns_mrvl_xspi_setup_clock(): unexpected end of section .text.cdns_mrvl_xspi_setup_clock

Fixes: c5995abe1547 ("objtool: Improve error handling")
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/692e1e0d0b15a71bd35c6b4b87f3c75cd5a57358.1743481539.git.jpoimboe@kernel.org

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objtool: Ignore end-of-section jumps for KCOV/GCOV

When KCOV or GCOV is enabled, dead code can be left behind, in which
case objtool silences unreachable and undefined behavior (fallthrough)
warning

objtool: Ignore end-of-section jumps for KCOV/GCOV

When KCOV or GCOV is enabled, dead code can be left behind, in which
case objtool silences unreachable and undefined behavior (fallthrough)
warnings.

Fallthrough warnings, and their variant "end of section" warnings, were
silenced with the following commit:

6b023c784204 ("objtool: Silence more KCOV warnings")

Another variant of a fallthrough warning is a jump to the end of a
function. If that function happens to be at the end of a section, the
jump destination doesn't actually exist.

Normally that would be a fatal objtool error, but for KCOV/GCOV it's
just another undefined behavior fallthrough. Silence it like the
others.

Fixes the following warning:

drivers/iommu/dma-iommu.o: warning: objtool: iommu_dma_sw_msi+0x92: can't find jump dest instruction at .text+0x54d5

Fixes: 6b023c784204 ("objtool: Silence more KCOV warnings")
Reported-by: Randy Dunlap <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/08fbe7d7e1e20612206f1df253077b94f178d93e.1743481539.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/[email protected]/

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objtool: Fix STACK_FRAME_NON_STANDARD for cold subfunctions

The recent STACK_FRAME_NON_STANDARD refactoring forgot about .cold
subfunctions. They must also be ignored.

Fixes the following warning:

objtool: Fix STACK_FRAME_NON_STANDARD for cold subfunctions

The recent STACK_FRAME_NON_STANDARD refactoring forgot about .cold
subfunctions. They must also be ignored.

Fixes the following warning:

drivers/gpu/drm/vmwgfx/vmwgfx_msg.o: warning: objtool: vmw_recv_msg.cold+0x0: unreachable instruction

Fixes: c84301d706c5 ("objtool: Ignore entire functions rather than instructions")
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/70a09ec0b0704398b2bbfb3153ce3d7cb8a381be.1743136205.git.jpoimboe@kernel.org

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objtool: Fix segfault in ignore_unreachable_insn()

Check 'prev_insn' before dereferencing it.

Fixes: bd841d6154f5 ("objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings")
Reported-by: Arnd Bergmann

objtool: Fix segfault in ignore_unreachable_insn()

Check 'prev_insn' before dereferencing it.

Fixes: bd841d6154f5 ("objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings")
Reported-by: Arnd Bergmann <[email protected]>
Reported-by: Ingo Molnar <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/5df4ff89c9e4b9e788b77b0531234ffa7ba03e9e.1743136205.git.jpoimboe@kernel.org

Closes: https://lore.kernel.org/[email protected]
Closes: https://lore.kernel.org/[email protected]

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objtool, panic: Disable SMAP in __stack_chk_fail()

__stack_chk_fail() can be called from uaccess-enabled code. Make sure
uaccess gets disabled before calling panic().

Fixes the following warning:

objtool, panic: Disable SMAP in __stack_chk_fail()

__stack_chk_fail() can be called from uaccess-enabled code. Make sure
uaccess gets disabled before calling panic().

Fixes the following warning:

kernel/trace/trace_branch.o: error: objtool: ftrace_likely_update+0x1ea: call to __stack_chk_fail() with UACCESS enabled

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/a3e97e0119e1b04c725a8aa05f7bc83d98e657eb.1742852847.git.jpoimboe@kernel.org

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objtool: Remove redundant opts.noinstr dependency

The --noinstr dependecy on --link is already enforced in the cmdline arg
parsing code. Remove the redundant check.

Signed-off-by: Josh Poimboeuf <

objtool: Remove redundant opts.noinstr dependency

The --noinstr dependecy on --link is already enforced in the cmdline arg
parsing code. Remove the redundant check.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/0ead7ffa0f5be2e81aebbcc585e07b2c98702b44.1742852847.git.jpoimboe@kernel.org

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objtool: Reduce CONFIG_OBJTOOL_WERROR verbosity

Remove the following from CONFIG_OBJTOOL_WERROR:

* backtrace

* "upgraded warnings to errors" message

* cmdline args

This makes the default o

objtool: Reduce CONFIG_OBJTOOL_WERROR verbosity

Remove the following from CONFIG_OBJTOOL_WERROR:

* backtrace

* "upgraded warnings to errors" message

* cmdline args

This makes the default output less cluttered and makes it easier to spot
the actual warnings. Note the above options are still are available
with --verbose or OBJTOOL_VERBOSE=1.

Also, do the cmdline arg printing on all warnings, regardless of werror.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/d61df69f64b396fa6b2a1335588aad7a34ea9e71.1742852846.git.jpoimboe@kernel.org

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objtool: Improve error handling

Fix some error handling issues, improve error messages, properly
distinguish betwee errors and warnings, and generally try to make all
the error handling more consist

objtool: Improve error handling

Fix some error handling issues, improve error messages, properly
distinguish betwee errors and warnings, and generally try to make all
the error handling more consistent.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/3094bb4463dad29b6bd1bea03848d1571ace771c.1742852846.git.jpoimboe@kernel.org

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objtool: Properly disable uaccess validation

If opts.uaccess isn't set, the uaccess validation is disabled, but only
partially: it doesn't read the uaccess_safe_builtin list but still tries
to do th

objtool: Properly disable uaccess validation

If opts.uaccess isn't set, the uaccess validation is disabled, but only
partially: it doesn't read the uaccess_safe_builtin list but still tries
to do the validation. Disable it completely to prevent false warnings.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/0e95581c1d2107fb5f59418edf2b26bba38b0cbb.1742852846.git.jpoimboe@kernel.org

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objtool: Silence more KCOV warnings

In the past there were issues with KCOV triggering unreachable
instruction warnings, which is why unreachable warnings are now disabled
with CONFIG_KCOV.

Now som

objtool: Silence more KCOV warnings

In the past there were issues with KCOV triggering unreachable
instruction warnings, which is why unreachable warnings are now disabled
with CONFIG_KCOV.

Now some new KCOV warnings are showing up with GCC 14:

vmlinux.o: warning: objtool: cpuset_write_resmask() falls through to next function cpuset_update_active_cpus.cold()
drivers/usb/core/driver.o: error: objtool: usb_deregister() falls through to next function usb_match_device()
sound/soc/codecs/snd-soc-wcd934x.o: warning: objtool: .text.wcd934x_slim_irq_handler: unexpected end of section

All are caused by GCC KCOV not finishing an optimization, leaving behind
a never-taken conditional branch to a basic block which falls through to
the next function (or end of section).

At a high level this is similar to the unreachable warnings mentioned
above, in that KCOV isn't fully removing dead code. Treat it the same
way by adding these to the list of warnings to ignore with CONFIG_KCOV.

Reported-by: Ingo Molnar <[email protected]>
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/66a61a0b65d74e072d3dc02384e395edb2adc3c5.1742852846.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/[email protected]
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

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objtool: Fix init_module() handling

If IBT is enabled and a module uses the deprecated init_module() magic
function name rather than module_init(fn), its ENDBR will get removed,
causing an IBT failu

objtool: Fix init_module() handling

If IBT is enabled and a module uses the deprecated init_module() magic
function name rather than module_init(fn), its ENDBR will get removed,
causing an IBT failure during module load.

Objtool does print an obscure warning, but then does nothing to either
correct it or return an error.

Improve the usefulness of the warning and return an error so it will at
least fail the build with CONFIG_OBJTOOL_WERROR.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/366bfdbe92736cde9fb01d5d3eb9b98e9070a1ec.1742852846.git.jpoimboe@kernel.org

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objtool: Fix X86_FEATURE_SMAP alternative handling

For X86_FEATURE_SMAP alternatives which replace NOP with STAC or CLAC,
uaccess validation skips the NOP branch to avoid following impossible
code p

objtool: Fix X86_FEATURE_SMAP alternative handling

For X86_FEATURE_SMAP alternatives which replace NOP with STAC or CLAC,
uaccess validation skips the NOP branch to avoid following impossible
code paths, e.g. where a STAC would be patched but a CLAC wouldn't.

However, it's not safe to assume an X86_FEATURE_SMAP alternative is
patching STAC/CLAC. There can be other alternatives, like
static_cpu_has(), where both branches need to be validated.

Fix that by repurposing ANNOTATE_IGNORE_ALTERNATIVE for skipping either
original instructions or new ones. This is a more generic approach
which enables the removal of the feature checking hacks and the
insn->ignore bit.

Fixes the following warnings:

arch/x86/mm/fault.o: warning: objtool: do_user_addr_fault+0x8ec: __stack_chk_fail() missing __noreturn in .c/.h or NORETURN() in noreturns.h
arch/x86/mm/fault.o: warning: objtool: do_user_addr_fault+0x8f1: unreachable instruction

[ mingo: Fix up conflicts with recent x86 changes. ]

Fixes: ea24213d8088 ("objtool: Add UACCESS validation")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/de0621ca242130156a55d5d74fed86994dfa4c9c.1742852846.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

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objtool: Ignore entire functions rather than instructions

STACK_FRAME_NON_STANDARD applies to functions. Use a function-specific
ignore attribute in preparation for getting rid of insn->ignore.

Si

objtool: Ignore entire functions rather than instructions

STACK_FRAME_NON_STANDARD applies to functions. Use a function-specific
ignore attribute in preparation for getting rid of insn->ignore.

Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/4af13376567f83331a9372ae2bb25e11a3d0f055.1742852846.git.jpoimboe@kernel.org

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objtool: Fix detection of consecutive jump tables on Clang 20

The jump table detection code assumes jump tables are in the same order
as their corresponding indirect branches. That's apparently not

objtool: Fix detection of consecutive jump tables on Clang 20

The jump table detection code assumes jump tables are in the same order
as their corresponding indirect branches. That's apparently not always
true with Clang 20.

Fix that by changing how multiple jump tables are detected. In the
first detection pass, mark the beginning of each jump table so the
second pass can tell where one ends and the next one begins.

Fixes the following warnings:

vmlinux.o: warning: objtool: SiS_GetCRT2Ptr+0x1ad: stack state mismatch: cfa1=4+8 cfa2=5+16
sound/core/seq/snd-seq.o: warning: objtool: cc_ev_to_ump_midi2+0x589: return with modified stack frame

Fixes: be2f0b1e1264 ("objtool: Get rid of reloc->jump_table_start")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/141752fff614eab962dba6bdfaa54aa67ff03bba.1742852846.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

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