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From: Carlos O'Donell <carlos@redhat.com>
To: Khem Raj <raj.khem@gmail.com>, libc-alpha@sourceware.org
Cc: Mark Hatle <mark.hatle@kernel.crashing.org>,
	Mark Hatle <mark.hatle@windriver.com>
Subject: Re: [PATCH] elf/dl-deps.c: Make _dl_build_local_scope breadth first
Date: Thu, 13 Jan 2022 14:02:55 -0500	[thread overview]
Message-ID: <61940983-6adf-32fd-394d-74e6158eb323@redhat.com> (raw)
In-Reply-To: <20211209235354.1558088-1-raj.khem@gmail.com>

On 12/9/21 18:53, Khem Raj via Libc-alpha wrote:
> From: Mark Hatle <mark.hatle@windriver.com>
> 
> According to the ELF specification:
> 
> When resolving symbolic references, the dynamic linker examines the symbol
> tables with a breadth-first search.
> 
> This function was using a depth first search.  By doing so the conflict
> resolution reported to the prelinker (when LD_TRACE_PRELINKING=1 is set)
> was incorrect.  This caused problems when their were various circular
> dependencies between libraries.  The problem usually manifested itself by
> the wrong IFUNC being executed.
> 
> Similar issue has been reported here [1]
> 
> [BZ# 20488]
> 
> [1] https://sourceware.org/legacy-ml/libc-alpha/2016-05/msg00034.html
> 
> Signed-off-by: Mark Hatle <mark.hatle@kernel.crashing.org>
> Signed-off-by: Khem Raj <raj.khem@gmail.com>
This needs much more discussion before inclusion.

At the very least we need clear test cases that show the problem.

The alternative patch I would support is prelink support removal.

-- 
Cheers,
Carlos.


      parent reply	other threads:[~2022-01-13 19:03 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-09 23:53 Khem Raj
2022-01-11 19:26 ` Adhemerval Zanella
2022-01-12 19:08   ` Mark Hatle
2022-01-12 20:12     ` Adhemerval Zanella
2022-01-12 20:41       ` Mark Hatle
2022-01-13 11:52         ` Adhemerval Zanella
2022-01-13 16:33           ` Mark Hatle
2022-01-13 17:20             ` Adhemerval Zanella
2022-01-13 18:00               ` Mark Hatle
2022-01-13 18:37                 ` Adhemerval Zanella
2022-01-13 19:01                   ` Carlos O'Donell
2022-01-13 19:02 ` Carlos O'Donell [this message]

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