mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Brendan Higgins <brendanhiggins@google.com>
To: jdike@addtoit.com, richard@nod.at,
	anton.ivanov@cambridgegreys.com, akpm@linux-foundation.org,
	changbin.du@intel.com, yamada.masahiro@socionext.com,
	rdunlap@infradead.org, keescook@chromium.org,
	andriy.shevchenko@linux.intel.com
Cc: linux-um@lists.infradead.org, linux-kernel@vger.kernel.org,
	davidgow@google.com, heidifahim@google.com,
	Brendan Higgins <brendanhiggins@google.com>
Subject: [RFC v1 0/2] arch: um: turn BTF_TYPEINFO support off
Date: Mon, 27 Jan 2020 11:35:47 -0800	[thread overview]
Message-ID: <20200127193549.187419-1-brendanhiggins@google.com> (raw)

As a part of my quest to get allyesconfig working on UML, I found a new
build error, with CONFIG_DEBUG_INFO_BTF=y:

scripts/link-vmlinux.sh: line 106: 17463 Segmentation fault      LLVM_OBJCOPY=${OBJCOPY} ${PAHOLE} -J ${1}
objcopy: --change-section-vma .BTF=0x0000000000000000 never used
objcopy: --change-section-lma .BTF=0x0000000000000000 never used
objcopy: error: the input file '.btf.vmlinux.bin' is empty
Failed to generate BTF for vmlinux
Try to disable CONFIG_DEBUG_INFO_BTF
make: *** [Makefile:1078: vmlinux] Error 1

The most interesting bit seems to be the:

objcopy: error: the input file '.btf.vmlinux.bin' is empty

Thinking about it, I am not sure if it makes sense for UML to produce
BTF type information, so I proposed a fix here that:

 1. Adds the ability for architectures to turn BTF support off.
 2. Turns BTF support off for UML.

I am also totally fine with just saying that DEBUG_INFO_BTF
depends on !UML, but I figured people would prefer this approach more.

Brendan Higgins (2):
  kbuild: add arch specific dependency for BTF support
  arch: um: turn BTF_TYPEINFO support off

 arch/um/Kconfig   | 1 +
 lib/Kconfig.debug | 5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)

-- 
2.25.0.341.g760bfbb309-goog


             reply	other threads:[~2020-01-27 19:35 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-27 19:35 Brendan Higgins [this message]
2020-01-27 19:35 ` [RFC v1 1/2] kbuild: add arch specific dependency for BTF support Brendan Higgins
2020-01-28  3:27   ` Masahiro Yamada
2020-01-28  7:25     ` Brendan Higgins
2020-01-27 19:35 ` [RFC v1 2/2] arch: um: turn BTF_TYPEINFO support off Brendan Higgins
2020-01-28  8:12   ` Anton Ivanov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200127193549.187419-1-brendanhiggins@google.com \
    --to=brendanhiggins@google.com \
    --cc=akpm@linux-foundation.org \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=anton.ivanov@cambridgegreys.com \
    --cc=changbin.du@intel.com \
    --cc=davidgow@google.com \
    --cc=heidifahim@google.com \
    --cc=jdike@addtoit.com \
    --cc=keescook@chromium.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-um@lists.infradead.org \
    --cc=rdunlap@infradead.org \
    --cc=richard@nod.at \
    --cc=yamada.masahiro@socionext.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®