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From: Peter Maydell <peter.maydell@linaro.org>
To: dinglimin@cmss.chinamobile.com
Cc: Michael Tokarev <mjt@tls.msk.ru>,
	 "richard.henderson@linaro.org" <richard.henderson@linaro.org>,
	 "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Subject: Re: [PATCH] semihosting/uaccess.c: Replaced a malloc call with g_malloc.
Date: Wed, 26 Jul 2023 10:43:30 +0100	[thread overview]
Message-ID: <CAFEAcA8UdN4-DU4dAiY3VGLA77mLK-ohfFJs5+5fDt3v1mAAcg@mail.gmail.com> (raw)
In-Reply-To: <E1qOWH5-0002Du-U6@lists.gnu.org>

(Something went wrong with the quoting in your email. I've
fixed it up.)

On Wed, 26 Jul 2023 at 05:38, <dinglimin@cmss.chinamobile.com> wrote:
> Peter Maydell wrote:
> > The third part here, is that g_malloc() does not ever
> > fail -- it will abort() on out of memory. However
> > the code here is still handling g_malloc() returning NULL.
> > The equivalent for "we expect this might fail" (which we want
> > here, because the guest is passing us the length of memory
> > to try to allocate) is g_try_malloc().

> g_malloc() is preferred more than g_try_* functions, which return NULL on error,
> when the size of the requested allocation  is small.
> This is because allocating few bytes should not be a problem in a healthy system.

This is true. But in this particular case we cannot be sure
that the size of the allocation is small, because the size
is controlled by the guest. So we want g_try_malloc().

thanks
-- PMM


  reply	other threads:[~2023-07-26  9:44 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-25  8:06 [PATCH] semihosting/uaccess.c: Replaced a malloc call with g_malloc dinglimin
2023-07-25  8:13 ` Michael Tokarev
2023-07-25  9:00 ` dinglimin
2023-07-25  9:13   ` Michael Tokarev
2023-07-25  9:35     ` Peter Maydell
2023-07-26  4:37       ` 回复: " dinglimin
2023-07-26  9:43         ` Peter Maydell [this message]
2023-07-26 15:21           ` Richard Henderson
2023-07-27 14:56             ` Peter Maydell
2023-07-27 15:04               ` Daniel P. Berrangé
2023-07-27 16:31                 ` Richard Henderson
2023-07-28  5:12                   ` dinglimin
2023-07-28  9:35                     ` Peter Maydell
2023-07-28 10:50                       ` dinglimin
2023-07-28 11:27                         ` Peter Maydell
2023-07-28 12:16               ` Peter Maydell
2023-07-26  7:07       ` dinglimin
2023-07-25 10:57   ` dinglimin
  -- strict thread matches above, loose matches on Subject: below --
2024-02-26  9:06 dinglimin
2024-02-26  9:48 ` Philippe Mathieu-Daudé
2024-02-26 10:03   ` Daniel P. Berrangé
2024-02-26 10:16   ` Peter Maydell
2024-02-26 10:02 ` Zhao Liu

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