From: "H.J. Lu" <hjl.tools@gmail.com>
To: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH 3/3] csu: Move static pie self relocation later [BZ #27072]
Date: Thu, 7 Jan 2021 04:36:22 -0800 [thread overview]
Message-ID: <CAMe9rOrpSP54qoH9L_Jp7eMc3NArHFxoyGX=v25ygcGL3iktJw@mail.gmail.com> (raw)
In-Reply-To: <1bfa01e6e92073b30c02cb76a209656b9d97b675.1610016590.git.szabolcs.nagy@arm.com>
On Thu, Jan 7, 2021 at 3:04 AM Szabolcs Nagy via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> On targets where hidden symbol access does not need RELATIVE
> relocs, move the static pie self relocation after tunables and
> cpu features are set up. This allows processing IRELATIVE
> relocs with correct ifunc dispatch logic.
>
> Unfortunately it is hard to guarantee that there will be no
> dynamic relocations in the early start up code, so this is a
> bit fragile. Ideally the RELATIVE relocs would be processed as
> early as possible and IRELATIVE relocs after cpu features are
> setup, but in glibc it is hard to separate them into two steps.
x86 linker places IRELATIVE relocations the last:
https://sourceware.org/bugzilla/show_bug.cgi?id=13302
Does your linker have this bug fixed?
--
H.J.
next prev parent reply other threads:[~2021-01-07 12:36 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-07 11:00 [PATCH 0/3] fix ifunc with static pie " Szabolcs Nagy
2021-01-07 11:01 ` [PATCH 1/3] Make libc symbols hidden in static PIE Szabolcs Nagy
2021-01-07 11:01 ` [PATCH 2/3] [RFC] elf: hack up tunables to avoid RELATIVE relocs Szabolcs Nagy
2021-01-07 13:50 ` Siddhesh Poyarekar
2021-01-07 11:01 ` [PATCH 3/3] csu: Move static pie self relocation later [BZ #27072] Szabolcs Nagy
2021-01-07 12:36 ` H.J. Lu [this message]
2021-01-07 12:46 ` Carlos O'Donell
2021-01-07 12:51 ` H.J. Lu
2021-01-07 13:02 ` Szabolcs Nagy
2021-01-07 14:25 ` Szabolcs Nagy
2021-01-07 14:48 ` Siddhesh Poyarekar
2021-01-07 15:25 ` Szabolcs Nagy
2021-01-07 17:48 ` H.J. Lu
2021-01-07 21:03 ` H.J. Lu
2021-01-08 10:08 ` Szabolcs Nagy
2021-01-07 12:48 ` [PATCH 0/3] fix ifunc with static pie " H.J. Lu
2021-01-07 12:50 ` Carlos O'Donell
2021-01-07 12:55 ` H.J. Lu
2021-01-07 13:03 ` Szabolcs Nagy
2021-01-07 13:15 ` H.J. Lu
2021-01-07 13:28 ` Szabolcs Nagy
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