Josh Poimboeuf 0d7597749f 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:

  6b023c7842 ("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: 6b023c7842 ("objtool: Silence more KCOV warnings")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/08fbe7d7e1e20612206f1df253077b94f178d93e.1743481539.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/314f8809-cd59-479b-97d7-49356bf1c8d1@infradead.org/
2025-04-01 09:07:12 +02:00
2024-09-01 20:43:24 -07:00
2022-09-28 09:02:20 +02:00
2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 3.4 GiB
Languages
C 97%
Assembly 1%
Shell 0.6%
Rust 0.5%
Python 0.4%
Other 0.3%