linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sedat Dilek <sedat.dilek@gmail.com>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>,
	Sami Tolvanen <samitolvanen@google.com>, X86 ML <x86@kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Kees Cook <keescook@chromium.org>,
	Clang-Built-Linux ML <clang-built-linux@googlegroups.com>,
	Miroslav Benes <mbenes@suse.cz>,
	Fangrui Song <maskray@google.com>,
	Peter Collingbourne <pcc@google.com>
Subject: Re: [PATCH v2 00/20] objtool: vmlinux.o and CLANG LTO support
Date: Sat, 23 Jan 2021 03:31:20 +0100	[thread overview]
Message-ID: <CA+icZUX9mYAFE6aFdmGS+rnJbeBMMMeVBrSs_pC6ragzXCjT7w@mail.gmail.com> (raw)
In-Reply-To: <20210123022609.n7xsj2a4potoijz7@treble>

On Sat, Jan 23, 2021 at 3:26 AM Josh Poimboeuf <jpoimboe@redhat.com> wrote:
>
> On Fri, Jan 22, 2021 at 05:32:43PM -0800, Nick Desaulniers wrote:
> > > In this specific case, find_func_by_offset returns NULL for
> > > .text..L.cfi.jumptable.43 at addend 0x8, because Clang doesn't emit
> > > jump table symbols for static functions:
> > >
> > > 0000000000000000 <__typeid__ZTSFjmiE_global_addr>:
> > >    0:   e9 00 00 00 00          jmpq   5 <__typeid__ZTSFjmiE_global_addr+0x5>
> > >                         1: R_X86_64_PLT32       io_serial_in-0x4
> > >    5:   cc                      int3
> > >    6:   cc                      int3
> > >    7:   cc                      int3
> > >    8:   e9 00 00 00 00          jmpq   d <__typeid__ZTSFjmiE_global_addr+0xd>
> > >                         9: R_X86_64_PLT32       mem32_serial_in-0x4
> > >    d:   cc                      int3
> > >    e:   cc                      int3
> > >    f:   cc                      int3
> > >
> > > Nick, do you remember if there were plans to change this?
> >
> > Do you have a link to any previous discussion to help jog my mind; I
> > don't really remember this one.
> >
> > Is it that `__typeid__ZTSFjmiE_global_addr` is the synthesized jump
> > table, and yet there is no `__typeid__ZTSFjmiE_global_addr` entry in
> > the symbol table?
>
> I think he means there's not a 'mem32_serial_in.cfi_jt' symbol at
> '__typeid__ZTSFjmiE_global_addr+8'.  Probably more aggressive symbol
> pruning from the assembler.
>
> It's fine though.  I just need to rewrite the CFI support a bit.
>
> But that can come later.  For now I'll just drop the two CFI-related
> patches from this set so I can merge the others next week.
>

Two CFI-related patches?

What's the other than "objtool: Add CONFIG_CFI_CLANG support"?

Do you plan (or offer) a v3 of objtool-vmlinux?

Thanks.

- Sedat -

[1] https://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linux.git/commit/?h=objtool-vmlinux-v2&id=d743f4b36e120c06506567a9f87a062ae03da47f

  reply	other threads:[~2021-01-23  2:32 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-21 21:29 [PATCH v2 00/20] objtool: vmlinux.o and CLANG LTO support Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 01/20] objtool: Fix error handling for STD/CLD warnings Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 02/20] objtool: Fix retpoline detection in asm code Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 03/20] objtool: Fix ".cold" section suffix check for newer versions of GCC Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 04/20] objtool: Support retpoline jump detection for vmlinux.o Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 05/20] x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 06/20] objtool: Assume only ELF functions do sibling calls Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 07/20] objtool: Add asm version of STACK_FRAME_NON_STANDARD Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 08/20] objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNC Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 09/20] objtool: Add xen_start_kernel() to noreturn list Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 10/20] objtool: Move unsuffixed symbol conversion to a helper function Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 11/20] objtool: Add CONFIG_CFI_CLANG support Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 12/20] x86/xen: Support objtool validation in xen-asm.S Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 13/20] x86/xen: Support objtool vmlinux.o validation in xen-head.S Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 14/20] x86/xen/pvh: Annotate indirect branch as safe Josh Poimboeuf
2021-01-22  5:17   ` Jürgen Groß
2021-01-21 21:29 ` [PATCH v2 15/20] x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.S Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 16/20] x86/acpi: Annotate indirect branch as safe Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 17/20] x86/acpi: Support objtool validation in wakeup_64.S Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 18/20] x86/power: Annotate indirect branches as safe Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 19/20] x86/power: Move restore_registers() to top of the file Josh Poimboeuf
2021-01-21 21:29 ` [PATCH v2 20/20] x86/power: Support objtool validation in hibernate_asm_64.S Josh Poimboeuf
2021-01-21 22:38 ` [PATCH v2 00/20] objtool: vmlinux.o and CLANG LTO support Sedat Dilek
2021-01-22 15:41   ` Josh Poimboeuf
2021-01-22 21:17     ` Sami Tolvanen
2021-01-23  1:32       ` Nick Desaulniers
2021-01-23  2:26         ` Josh Poimboeuf
2021-01-23  2:31           ` Sedat Dilek [this message]
2021-01-23  2:46             ` Josh Poimboeuf
2021-01-23  2:50               ` Sedat Dilek
2021-01-25 22:43           ` Sami Tolvanen

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=CA+icZUX9mYAFE6aFdmGS+rnJbeBMMMeVBrSs_pC6ragzXCjT7w@mail.gmail.com \
    --to=sedat.dilek@gmail.com \
    --cc=clang-built-linux@googlegroups.com \
    --cc=jpoimboe@redhat.com \
    --cc=keescook@chromium.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maskray@google.com \
    --cc=mbenes@suse.cz \
    --cc=ndesaulniers@google.com \
    --cc=pcc@google.com \
    --cc=peterz@infradead.org \
    --cc=samitolvanen@google.com \
    --cc=x86@kernel.org \
    /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;
as well as URLs for NNTP newsgroup(s).