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From: Florian Weimer <fweimer@redhat.com>
To: Szabolcs Nagy <nsz@port70.net>
Cc: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>,
	 Szabolcs Nagy <szabolcs.nagy@arm.com>,
	 libc-alpha@sourceware.org
Subject: Re: [PATCH] aarch64: Remove ld.so __tls_get_addr plt usage
Date: Mon, 08 Apr 2024 10:04:55 +0200	[thread overview]
Message-ID: <87frvw1dqw.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <20240406174016.GD3766212@port70.net> (Szabolcs Nagy's message of "Sat, 6 Apr 2024 19:40:16 +0200")

* Szabolcs Nagy:

> * Adhemerval Zanella Netto <adhemerval.zanella@linaro.org> [2024-04-05 13:29:48 -0300]:
>
>> 
>> 
>> On 05/04/24 11:58, Szabolcs Nagy wrote:
>> > The 04/05/2024 09:35, Adhemerval Zanella wrote:
>> >> Use the hidden alias instead.
>> >>
>> >> Checked on aarch64-linux-gnu.
>> > 
>> > does this change behaviour in case __tls_get_addr is interposed?
>> > 
>> > 
>> 
>> Do we support symbol interposition for symbols in implementation namespace?
>> If so, we will need to revert x86 to use the same semantic and document it
>> properly.
>
> i suspect this will partially break the sanitizers
> and possibly other similar tools that hook internals
> so i hoped at least for better commit msg pointing
> out that this is deliberate behaviour change.

There is a __tls_get_addr interceptor, but I'm not sure what it does,
exactly.  If the initial-exec optimization kicks in, this code path
isn't even used.  I think we should try if removing the indirect call
helps.

Thanks,
Florian


  reply	other threads:[~2024-04-08  8:05 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-05 12:35 Adhemerval Zanella
2024-04-05 14:58 ` Szabolcs Nagy
2024-04-05 16:29   ` Adhemerval Zanella Netto
2024-04-06 17:40     ` Szabolcs Nagy
2024-04-08  8:04       ` Florian Weimer [this message]
2024-04-07 20:29   ` Cristian Rodríguez
2024-04-08  7:26     ` Szabolcs Nagy
2024-04-08 16:57       ` Adhemerval Zanella Netto
2024-04-09  8:30         ` Szabolcs Nagy
2024-04-09 14:03           ` Adhemerval Zanella Netto
2024-04-09 14:05             ` H.J. Lu
2024-04-09 14:11             ` Palmer Dabbelt
2024-04-09 14:46               ` H.J. Lu
2024-04-09 17:50             ` Fangrui Song
2024-04-10  7:29               ` Szabolcs Nagy
2024-04-10  8:23               ` Florian Weimer
2024-04-10 15:46                 ` enh
2024-04-15 11:41                   ` Florian Weimer
2024-04-15 20:22                 ` Adhemerval Zanella Netto

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