From: Florian Weimer <fw@deneb.enyo.de>
To: "H.J. Lu" <hjl.tools@gmail.com>
Cc: "H.J. Lu via Libc-alpha" <libc-alpha@sourceware.org>
Subject: Re: [PATCH] Add SYSCALL_LONG/SYSCALL_ULONG to pass long to syscall [BZ #25810]
Date: Sat, 11 Apr 2020 16:45:24 +0200 [thread overview]
Message-ID: <87v9m684jf.fsf@mid.deneb.enyo.de> (raw)
In-Reply-To: <CAMe9rOqP_s6nUnxZOphja3HXLcvjBd7bQ0wHxijLYLFQBO3trw@mail.gmail.com> (H. J. Lu's message of "Sat, 11 Apr 2020 06:26:08 -0700")
* H. J. Lu:
> On Sat, Apr 11, 2020 at 3:01 AM Florian Weimer <fw@deneb.enyo.de> wrote:
>>
>> * H. J. Lu via Libc-alpha:
>>
>> > For inline syscalls, SYSCALL_LONG and SYSCALL_ULONG are introduced as
>> > wrappers for long and unsigned long arguments.
>>
>> Do the arguments have the correct types? Then I think you can do the
>
> Yes, they have correct types. But it is not the problem. Take this example:
>
> int munmap(void *addr, size_t length);
>
> The type of length is unsigned int (size_t) for x32 and is unsigned long
> (64bit) in kernel. We have no way to know the type which kernel expects.
Is it possible to extend all 32-bit arguments? Ot is this incorrect
for negative int arguments, which must not have their upper bits set?
next prev parent reply other threads:[~2020-04-11 14:45 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-10 21:22 H.J. Lu
2020-04-11 10:01 ` Florian Weimer
2020-04-11 13:26 ` H.J. Lu
2020-04-11 14:45 ` Florian Weimer [this message]
2020-04-11 15:04 ` H.J. Lu
2020-04-11 15:10 ` Florian Weimer
2020-04-11 15:23 ` H.J. Lu
2020-04-11 15:31 ` Florian Weimer
2020-04-11 20:25 ` H.J. Lu
2020-04-11 20:47 ` Florian Weimer
2020-04-11 21:58 ` H.J. Lu
2020-04-12 20:44 ` Florian Weimer
2020-04-12 22:42 ` H.J. Lu
2020-04-13 8:23 ` Florian Weimer
2020-04-13 11:44 ` H.J. Lu
2020-04-13 11:54 ` H.J. Lu
2020-04-13 14:26 ` H.J. Lu
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