qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Peter Maydell <peter.maydell@linaro.org>
To: "Alex Bennée" <alex.bennee@linaro.org>
Cc: qemu-arm <qemu-arm@nongnu.org>, QEMU Developers <qemu-devel@nongnu.org>
Subject: Re: [PATCH v4 2/2] tests/tcg: port SYS_HEAPINFO to a system test
Date: Wed, 9 Feb 2022 19:02:48 +0000	[thread overview]
Message-ID: <CAFEAcA87H4OibHzuz=EycSEFo=jAzMoCxij8KDdoFHjrp54vjQ@mail.gmail.com> (raw)
In-Reply-To: <87k0e3ewjg.fsf@linaro.org>

On Wed, 9 Feb 2022 at 18:15, Alex Bennée <alex.bennee@linaro.org> wrote:
>
>
> Peter Maydell <peter.maydell@linaro.org> writes:
>
> > On Wed, 9 Feb 2022 at 17:26, Alex Bennée <alex.bennee@linaro.org> wrote:
> >> It should be in this case because boot.S sets stack to be inside out
> >> data segment.
> >
> > So what you mean is
> >
> >  /*
> >   * boot.S put our stack somewhere inside the text segment of the
> >   * ELF file, and we know that SYS_HEAPINFO won't pick a range
> >   * that overlaps with part of a loaded ELF file. So the info
> >   * struct (on the stack) should not be inside the reported heap.
> >   */
> >
> > ?
>
> Well the data segment (but not the bss).

Ah, yes, I missed the ".data" when I was scanning the file.
(For a system binary it doesn't matter, because our ELF loader
doesn't care whether the segment is marked read-only or
read-write, it just loads it into RAM.)

> So as long as the ELF loader
> includes that in the calculation (which it should I think) then we are
> ok.

Should be OK -- the ELF loader creates a rom blob for every
segment in the file, and then the SYS_HEAPINFO implementation
will avoid them all.

-- PMM


      reply	other threads:[~2022-02-09 19:09 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-23 13:47 [PATCH v4 0/2] semihosting/next (SYS_HEAPINFO) Alex Bennée
2021-06-23 13:47 ` [PATCH v4 1/2] semihosting/arm-compat: replace heuristic for softmmu SYS_HEAPINFO Alex Bennée
2021-06-28 19:48   ` Peter Maydell
2022-02-09 16:29     ` Alex Bennée
2022-02-09 17:13       ` Peter Maydell
2021-06-23 13:47 ` [PATCH v4 2/2] tests/tcg: port SYS_HEAPINFO to a system test Alex Bennée
2021-06-28 20:01   ` Peter Maydell
2022-02-09 17:25     ` Alex Bennée
2022-02-09 17:44       ` Peter Maydell
2022-02-09 18:14         ` Alex Bennée
2022-02-09 19:02           ` Peter Maydell [this message]

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='CAFEAcA87H4OibHzuz=EycSEFo=jAzMoCxij8KDdoFHjrp54vjQ@mail.gmail.com' \
    --to=peter.maydell@linaro.org \
    --cc=alex.bennee@linaro.org \
    --cc=qemu-arm@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    /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 NNTP newsgroup(s).