public inbox for libc-alpha@sourceware.org
 help / color / mirror / Atom feed
From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH v6 02/14] aarch64: configure test for BTI support
Date: Mon, 6 Jul 2020 15:12:32 -0300	[thread overview]
Message-ID: <5dfd90f6-e23a-e404-27e2-e0451bdc6e21@linaro.org> (raw)
In-Reply-To: <20200706180730.GE31737@arm.com>



On 06/07/2020 15:07, Szabolcs Nagy wrote:
> The 07/06/2020 11:11, Adhemerval Zanella via Libc-alpha wrote:
>>
>>
>> On 01/07/2020 11:38, Szabolcs Nagy wrote:
>>> Check BTI support in the compiler and linker.  The check also
>>> requires READELF that understands the BTI GNU property note.
>>> It is expected to succeed with gcc >=gcc-9 configured with
>>> --enable-standard-branch-protection and binutils >=binutils-2.33.
>>>
>>> Note: passing -mbranch-protection=bti in CFLAGS when building glibc
>>> may not be enough to get a glibc that supports BTI because crtbegin*
>>> and crtend* provided by the compiler needs to be BTI compatible too.
>>
>> If I read correctly this scenario should be covered by the configure
>> test, right?
> 
> it is not covered because the config checks use -nostdlib
> and -nostartfiles (otherwise objects from the libc that
> the toolchain uses would leak into the checks).
> 
> so if gcc startfiles are not bti compatible then configure
> succeeds (but later on there will be link failures so the
> build fails).

Right, would be hard to try to fail early on configure for this
case?

  reply	other threads:[~2020-07-06 18:12 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-01 14:37 [PATCH v6 00/14] aarch64: branch protection support Szabolcs Nagy
2020-07-01 14:37 ` [PATCH v6 01/14] Rewrite abi-note.S in C Szabolcs Nagy
2020-07-01 14:41   ` H.J. Lu
2020-07-01 17:31     ` Szabolcs Nagy
2020-07-01 17:43       ` H.J. Lu
2020-07-02  8:39         ` Szabolcs Nagy
2020-07-01 14:38 ` [PATCH v6 02/14] aarch64: configure test for BTI support Szabolcs Nagy
2020-07-06 14:11   ` Adhemerval Zanella
2020-07-06 18:07     ` Szabolcs Nagy
2020-07-06 18:12       ` Adhemerval Zanella [this message]
2020-07-07 14:26         ` Szabolcs Nagy
2020-07-07 14:39           ` H.J. Lu
2020-07-07 16:58             ` Szabolcs Nagy
2020-07-07 17:24               ` H.J. Lu
2020-07-01 14:38 ` [PATCH v6 03/14] aarch64: Rename place holder .S files to .c Szabolcs Nagy
2020-07-01 14:38 ` [PATCH v6 04/14] aarch64: Add BTI support to assembly files Szabolcs Nagy
2020-07-03 16:19   ` Szabolcs Nagy
2020-07-01 14:38 ` [PATCH v6 05/14] aarch64: fix swapcontext for BTI Szabolcs Nagy
2020-07-01 14:39 ` [PATCH v6 06/14] aarch64: fix RTLD_START " Szabolcs Nagy
2020-07-01 14:39 ` [PATCH v6 07/14] rtld: Clean up PT_NOTE and add PT_GNU_PROPERTY handling Szabolcs Nagy
2020-07-06 16:11   ` Adhemerval Zanella
2020-07-01 14:39 ` [PATCH v6 08/14] aarch64: enable BTI at runtime Szabolcs Nagy
2020-07-06 17:28   ` Adhemerval Zanella
2020-07-11 15:58   ` Richard Henderson
2020-07-13  8:32     ` Szabolcs Nagy
2020-07-13 13:14     ` Szabolcs Nagy
2020-07-13 13:28       ` Szabolcs Nagy
2020-07-13 16:55         ` Richard Henderson
2020-07-01 14:39 ` [PATCH v6 09/14] aarch64: ensure objects are BTI compatible Szabolcs Nagy
2020-07-06 17:37   ` Adhemerval Zanella
2020-07-06 18:01     ` Szabolcs Nagy
2020-07-06 18:17       ` Adhemerval Zanella
2020-07-01 14:40 ` [PATCH v6 10/14] aarch64: configure check for pac-ret code generation Szabolcs Nagy
2020-07-01 14:40 ` [PATCH v6 11/14] aarch64: Add pac-ret support to assembly files Szabolcs Nagy
2020-07-01 14:40 ` [PATCH v6 12/14] aarch64: fix pac-ret support in _mcount Szabolcs Nagy
2020-07-06 18:33   ` Adhemerval Zanella
2020-07-01 14:40 ` [PATCH v6 13/14] aarch64: redefine RETURN_ADDRESS to strip PAC Szabolcs Nagy
2020-07-06 18:34   ` Adhemerval Zanella
2020-07-01 14:41 ` [PATCH v6 14/14] aarch64: add NEWS entry about branch protection support Szabolcs Nagy
2020-07-06 18:41   ` Adhemerval Zanella
2020-07-08 10:04     ` Szabolcs Nagy

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=5dfd90f6-e23a-e404-27e2-e0451bdc6e21@linaro.org \
    --to=adhemerval.zanella@linaro.org \
    --cc=libc-alpha@sourceware.org \
    --cc=szabolcs.nagy@arm.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;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).