From: Szabolcs Nagy <szabolcs.nagy@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
David Miller <davem@davemloft.net>
Cc: <nd@arm.com>, <arnd@arndb.de>, <ynorov@caviumnetworks.com>,
<linux-arm-kernel@lists.infradead.org>,
<linux-kernel@vger.kernel.org>, <linux-doc@vger.kernel.org>,
<linux-arch@vger.kernel.org>, <linux-s390@vger.kernel.org>,
<libc-alpha@sourceware.org>, <schwidefsky@de.ibm.com>,
<heiko.carstens@de.ibm.com>, <pinskia@gmail.com>,
<broonie@kernel.org>, <joseph@codesourcery.com>,
<christoph.muellner@theobroma-systems.com>,
<bamvor.zhangjian@huawei.com>, <klimov.linux@gmail.com>,
<Nathan_Lynch@mentor.com>, <agraf@suse.de>,
<Prasun.Kapoor@caviumnetworks.com>, <kilobyte@angband.pl>,
<geert@linux-m68k.org>, <philipp.tomsich@theobroma-systems.com>
Subject: Re: [PATCH 01/23] all: syscall wrappers: add documentation
Date: Thu, 26 May 2016 15:50:01 +0100 [thread overview]
Message-ID: <57470D19.2000501@arm.com> (raw)
In-Reply-To: <20160526142057.GA7456@e104818-lin.cambridge.arm.com>
On 26/05/16 15:20, Catalin Marinas wrote:
> While writing the above, I realised the current ILP32 patches still miss
> on converting pointers passed from user space (unless I got myself
> confused in macros). The new __SC_WRAP() and COMPAT_SYSCALL_WRAPx()
> macros take care of zero or sign extension via __SC_COMPAT_CAST().
> However, we have two more existing cases which I don't see covered:
>
> a) Native syscalls taking a pointer argument and invoked directly from
> ILP32. For example, sys_read() takes a pointer but I don't see any
> __SC_WRAP added by patch 5
>
> b) Current compat syscalls taking a pointer argument. For example,
> compat_sys_vmsplice() gets the iov32 pointer and the compiler assumes
> it is a 64-bit variable. I don't see where the upper half is zeroed
>
on x32 sign/zero extension is currently left to userspace,
which is difficult to deal with, (long long)arg does the
wrong thing for pointer args.
> We can solve (a) by adding more __SC_WRAP annotations in the generic
> unistd.h. For (b), we would need an __SC_DELOUSE with a bit of penalty
> on AArch32/compat support where it isn't needed. So maybe davem has a
> point on the overall impact of always zeroing the upper half of the
> arguments ;) (both from a performance and maintainability perspective).
> I guess this part of the ABI is still up for discussion.
>
next prev parent reply other threads:[~2016-05-26 14:50 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-24 0:04 [PATCH v6 00/21] ILP32 for ARM64 Yury Norov
2016-05-24 0:04 ` [PATCH 01/23] all: syscall wrappers: add documentation Yury Norov
2016-05-25 19:30 ` David Miller
2016-05-25 20:03 ` Yury Norov
2016-05-25 20:21 ` David Miller
2016-05-25 20:47 ` Arnd Bergmann
2016-05-25 20:50 ` David Miller
2016-05-25 21:01 ` Arnd Bergmann
2016-05-25 21:28 ` David Miller
2016-05-26 14:20 ` Catalin Marinas
2016-05-26 14:50 ` Szabolcs Nagy [this message]
2016-05-26 15:19 ` Catalin Marinas
2016-05-26 19:43 ` David Miller
2016-05-27 10:10 ` Catalin Marinas
2016-05-26 20:48 ` Yury Norov
2016-05-26 22:29 ` Catalin Marinas
2016-05-27 0:37 ` Yury Norov
2016-05-27 6:03 ` Heiko Carstens
2016-05-27 8:42 ` Arnd Bergmann
2016-05-27 9:30 ` Catalin Marinas
2016-05-27 10:49 ` Arnd Bergmann
2016-05-27 13:04 ` Catalin Marinas
2016-05-27 16:58 ` Yury Norov
2016-05-27 17:36 ` Catalin Marinas
2016-05-27 9:01 ` Catalin Marinas
2016-06-14 23:08 ` Yury Norov
2016-05-27 5:52 ` Heiko Carstens
2016-05-24 0:04 ` [PATCH 02/23] all: introduce COMPAT_WRAPPER option and enable it for s390 Yury Norov
2016-05-24 0:04 ` [PATCH 03/23] all: s390: move wrapper infrastructure to generic headers Yury Norov
2016-05-24 0:04 ` [PATCH 04/23] all: s390: move compat_wrappers.c from arch/s390/kernel to kernel/ Yury Norov
2016-05-24 0:04 ` [PATCH 05/23] all: wrap needed syscalls in generic unistd Yury Norov
2016-05-24 0:04 ` [PATCH 06/23] compat ABI: use non-compat openat and open_by_handle_at variants Yury Norov
2016-05-24 0:04 ` [PATCH 07/23] 32-bit ABI: introduce ARCH_32BIT_OFF_T config option Yury Norov
2016-05-24 0:04 ` [PATCH 08/23] arm64: ilp32: add documentation on the ILP32 ABI for ARM64 Yury Norov
2016-05-24 0:04 ` [PATCH 09/23] arm64: ensure the kernel is compiled for LP64 Yury Norov
2016-05-24 0:04 ` [PATCH 10/23] arm64: rename COMPAT to AARCH32_EL0 in Kconfig Yury Norov
2016-05-24 0:04 ` [PATCH 11/23] arm64:uapi: set __BITS_PER_LONG correctly for ILP32 and LP64 Yury Norov
2016-05-24 0:04 ` [PATCH 12/23] thread: move thread bits accessors to separated file Yury Norov
2016-05-24 0:04 ` [PATCH 13/23] arm64: introduce is_a32_task and is_a32_thread (for AArch32 compat) Yury Norov
2016-06-12 12:21 ` Zhangjian (Bamvor)
2016-06-12 13:08 ` Zhangjian (Bamvor)
2016-06-12 17:56 ` Yury Norov
2016-05-24 0:04 ` [PATCH 14/23] arm64: ilp32: add is_ilp32_compat_{task,thread} and TIF_32BIT_AARCH64 Yury Norov
2016-05-24 0:04 ` [PATCH 15/23] arm64: introduce binfmt_elf32.c Yury Norov
2016-05-24 0:04 ` [PATCH 16/23] arm64: ilp32: introduce binfmt_ilp32.c Yury Norov
2016-05-26 13:49 ` Zhangjian (Bamvor)
2016-05-26 21:08 ` Yury Norov
2016-06-15 0:40 ` Yury Norov
2016-06-13 3:05 ` Zhangjian (Bamvor)
2016-06-13 13:22 ` Zhangjian (Bamvor)
2016-05-24 0:04 ` [PATCH 17/23] arm64: ptrace: handle ptrace_request differently for aarch32 and ilp32 Yury Norov
2016-06-08 1:34 ` zhouchengming
2016-06-08 17:00 ` Yury Norov
2016-06-25 9:36 ` zhouchengming
2016-06-25 14:15 ` Bamvor Zhang
2016-06-27 2:09 ` zhouchengming
2016-05-24 0:04 ` [PATCH 18/23] arm64: ilp32: add sys_ilp32.c and a separate table (in entry.S) to use it Yury Norov
2016-05-25 20:26 ` Arnd Bergmann
2016-05-24 0:04 ` [PATCH 19/23] arm64: signal: share lp64 signal routines to ilp32 Yury Norov
2016-05-24 0:04 ` [PATCH 20/23] arm64: signal32: move ilp32 and aarch32 common code to separated file Yury Norov
2016-05-24 0:04 ` [PATCH 21/23] arm64: ilp32: introduce ilp32-specific handlers for sigframe and ucontext Yury Norov
2016-06-04 11:34 ` Zhangjian (Bamvor)
2016-06-12 12:34 ` Zhangjian (Bamvor)
2016-06-12 13:12 ` Zhangjian (Bamvor)
2016-06-12 17:44 ` Yury Norov
2016-06-16 11:21 ` Zhangjian (Bamvor)
2016-06-12 12:39 ` Zhangjian (Bamvor)
2016-05-24 0:04 ` [PATCH 22/23] arm64:ilp32: add vdso-ilp32 and use for signal return Yury Norov
2016-05-24 0:04 ` [PATCH 23/23] arm64:ilp32: add ARM64_ILP32 to Kconfig Yury Norov
2016-05-25 10:42 ` [PATCH v6 00/21] ILP32 for ARM64 Szabolcs Nagy
2016-05-25 16:41 ` Yury Norov
2016-06-02 19:03 ` Yury Norov
2016-06-03 11:02 ` Szabolcs Nagy
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=57470D19.2000501@arm.com \
--to=szabolcs.nagy@arm.com \
--cc=Nathan_Lynch@mentor.com \
--cc=Prasun.Kapoor@caviumnetworks.com \
--cc=agraf@suse.de \
--cc=arnd@arndb.de \
--cc=bamvor.zhangjian@huawei.com \
--cc=broonie@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=christoph.muellner@theobroma-systems.com \
--cc=davem@davemloft.net \
--cc=geert@linux-m68k.org \
--cc=heiko.carstens@de.ibm.com \
--cc=joseph@codesourcery.com \
--cc=kilobyte@angband.pl \
--cc=klimov.linux@gmail.com \
--cc=libc-alpha@sourceware.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=nd@arm.com \
--cc=philipp.tomsich@theobroma-systems.com \
--cc=pinskia@gmail.com \
--cc=schwidefsky@de.ibm.com \
--cc=ynorov@caviumnetworks.com \
/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).