From: Szabolcs Nagy <Szabolcs.Nagy@arm.com>
To: "Fāng-ruì Sòng" <maskray@google.com>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>,
"H.J. Lu" <hjl.tools@gmail.com>,
Florian Weimer <fweimer@redhat.com>,
Andreas Schwab <schwab@linux-m68k.org>,
libc-alpha <libc-alpha@sourceware.org>,
Joseph Myers <joseph@codesourcery.com>
Subject: Re: [PATCH] dl: Use "adr" assembler command to get proper load address
Date: Fri, 8 Oct 2021 10:15:09 +0100 [thread overview]
Message-ID: <20211008091509.GH2700@arm.com> (raw)
In-Reply-To: <CAFP8O3+S-sOdQLqF5rhmJygah-HoGG4G0cpWK3+Q3PPE-TA--w@mail.gmail.com>
The 10/07/2021 10:24, Fāng-ruì Sòng wrote:
> &__ehdr_start was used long before "elf: Unconditionally use __ehdr_start"
> https://sourceware.org/git/?p=glibc.git;a=blobdiff;f=elf/rtld.c;h=878e6480f4980b2fef468d8e271cd68acd4fc2d0;hp=d733359eaf808b8a5579908a6cd1153062c02919;hb=302247c89121e8d4c7629e589edbb4974fff6edb;hpb=13710e7e6af6c8965cc9a63a0660cb4ce1966557
>
> It is surprising if that code could do something useful with prelinking.
__ehdr_start was used as the start of the elf header.
that's true even after prelinking does its offsets.
the new use of __ehdr_start is to mean the base address
by which local symbol vaddr needs to be offset to get
the runtime address. this use relies on __ehdr_start to
have 0 vaddr wihch is broken by prelinking that moves
everything to some offset.
in principle the elf object after prelinking is valid,
but since this is the ld.so we can say that we only
support the case when the elf header is at 0 vaddr.
next prev parent reply other threads:[~2021-10-08 9:15 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-07 13:16 Lukasz Majewski
2021-09-07 16:49 ` Fangrui Song
2021-09-07 17:32 ` Lukasz Majewski
2021-09-07 17:44 ` Fangrui Song
2021-09-08 15:05 ` Lukasz Majewski
2021-09-08 17:41 ` Fāng-ruì Sòng
2021-09-08 19:19 ` Adhemerval Zanella
2021-09-08 20:34 ` Lukasz Majewski
2021-09-09 7:18 ` Lukasz Majewski
2021-09-09 9:49 ` Lukasz Majewski
2021-09-10 10:10 ` Lukasz Majewski
2021-09-17 8:29 ` Lukasz Majewski
2021-09-17 13:27 ` Joseph Myers
2021-09-17 16:17 ` Andreas Schwab
2021-09-26 19:58 ` Lukasz Majewski
2021-09-27 16:00 ` Joseph Myers
2021-10-05 7:45 ` Lukasz Majewski
2021-10-06 7:57 ` Fangrui Song
2021-10-06 9:03 ` Lukasz Majewski
2021-10-06 11:43 ` Lukasz Majewski
2021-10-06 12:55 ` Szabolcs Nagy
2021-10-07 9:19 ` Lukasz Majewski
2021-10-07 10:00 ` Lukasz Majewski
2021-10-07 14:15 ` Szabolcs Nagy
2021-10-07 14:58 ` Lukasz Majewski
2021-10-07 14:16 ` Adhemerval Zanella
2021-10-07 14:29 ` H.J. Lu
2021-10-07 15:57 ` Szabolcs Nagy
2021-10-07 16:22 ` H.J. Lu
2021-10-07 16:53 ` Adhemerval Zanella
2021-10-07 17:05 ` H.J. Lu
2021-10-07 17:24 ` Fāng-ruì Sòng
2021-10-08 9:15 ` Szabolcs Nagy [this message]
2021-10-11 8:56 ` Lukasz Majewski
2021-10-11 10:18 ` Szabolcs Nagy
2021-10-11 11:47 ` Lukasz Majewski
2021-10-11 12:01 ` H.J. Lu
2021-10-11 13:10 ` Lukasz Majewski
2021-10-11 13:22 ` H.J. Lu
2021-10-11 14:31 ` Lukasz Majewski
2021-10-11 13:34 ` Adhemerval Zanella
2021-10-11 12:48 ` Szabolcs Nagy
2021-10-15 7:54 ` [PATCH v2] dl: Use "adr" assembler command to get proper load address on ARM Lukasz Majewski
2021-10-15 12:09 ` Szabolcs Nagy
2021-10-15 12:21 ` H.J. Lu
2021-10-15 12:59 ` Lukasz Majewski
2021-10-15 23:53 ` Fāng-ruì Sòng
2021-10-18 11:08 ` Szabolcs Nagy
2021-10-18 11:35 ` Florian Weimer
2021-10-19 12:03 ` Lukasz Majewski
2021-10-25 10:18 ` Lukasz Majewski
2021-10-25 10:25 ` Florian Weimer
2021-10-25 10:53 ` Lukasz Majewski
2021-10-25 13:34 ` Szabolcs Nagy
2021-10-25 14:04 ` Lukasz Majewski
2021-10-25 15:09 ` Szabolcs Nagy
2021-10-25 17:26 ` Joseph Myers
2021-10-26 13:52 ` Lukasz Majewski
2021-10-26 20:55 ` Joseph Myers
2021-10-27 9:38 ` Szabolcs Nagy
2021-10-25 18:25 ` Lukasz Majewski
2021-10-15 13:59 ` Lukasz Majewski
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