[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2
From: |
Aleksandar Markovic |
Subject: |
Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1 |
Date: |
Wed, 22 May 2019 15:22:23 +0200 |
On May 22, 2019 2:24 PM, "Cornelia Huck" <address@hidden> wrote:
>
> On Wed, 22 May 2019 14:10:39 +0200
> Laurent Vivier <address@hidden> wrote:
>
> > On 22/05/2019 14:07, Cornelia Huck wrote:
> > > On Wed, 22 May 2019 13:47:25 +0200
> > > Philippe Mathieu-Daudé <address@hidden> wrote:
> > >
> > >> On 5/21/19 5:28 PM, Cornelia Huck wrote:
> > >>> commit a188339ca5a396acc588e5851ed7e19f66b0ebd9
> > >>>
> > >>> Signed-off-by: Cornelia Huck <address@hidden>
> > >>> ---
> > >> [...]
> > >>> #define __NR_mq_notify 184
> > >>> __SC_COMP(__NR_mq_notify, sys_mq_notify, compat_sys_mq_notify)
> > >>> #define __NR_mq_getsetattr 185
> > >>> @@ -536,8 +567,10 @@ __SC_COMP(__NR_msgsnd, sys_msgsnd,
compat_sys_msgsnd)
> > >>> __SYSCALL(__NR_semget, sys_semget)
> > >>> #define __NR_semctl 191
> > >>> __SC_COMP(__NR_semctl, sys_semctl, compat_sys_semctl)
> > >>> +#if defined(__ARCH_WANT_TIME32_SYSCALLS) || __BITS_PER_LONG != 32
> > >
> > > Eww. It seems only aarch64 sets __ARCH_WANT_TIME32_SYSCALLS, and the
> > > second condition probably catches others but not mipsel.
> > >
> > >>> #define __NR_semtimedop 192
> > >>> -__SC_COMP(__NR_semtimedop, sys_semtimedop, compat_sys_semtimedop)
> > >>> +__SC_COMP(__NR_semtimedop, sys_semtimedop, sys_semtimedop_time32)
> > >>> +#endif
> > >>> #define __NR_semop 193
> > >>> __SYSCALL(__NR_semop, sys_semop)
> > >> [...]
> > >>
> > >> https://app.shippable.com/github/qemu/qemu/runs/1703/summary/console
> > >>
> > >> It seems this commit introduce a regression on mips32:
> > >>
> > >> CC mipsel-linux-user/linux-user/syscall.o
> > >> ./linux-user/syscall.c: In function 'safe_semtimedop':
> > >> ./linux-user/syscall.c:697:25: error: '__NR_semtimedop' undeclared
> > >> (first use in this function)
> > >> return safe_syscall(__NR_##name, arg1, arg2, arg3, arg4); \
> > >
> > > So, we unconditionally deal with this syscall, i.e. we assume it is
> > > always present? (I'm not sure of the logic in linux-user code.)
> > >
> >
> > linux-user assumes it is present if __NR_msgsnd is present.
>
> Hm. The kernel change seems to break that assumption. Does anyone with
> mips knowledge have an idea whether that was intentional (and the
> linux-user code needs to be changed), or whether that's an issue on the
> kernel side?
>
Hi, Cornelia.
Thanks for your involving into this issue!
It could be that (not-originating-from-MIPS) kernel commit:
https://github.com/torvalds/linux/commit/1a787fc5ba18ac767e635c58d06a0b46876184e3
made a mess with system call availability for MIPS (I will forward this to
MIPS kernel maintainer Paul Burton). My impression is that this was not
intentional, and is a temporary instability of kernel interface.
However, I think that QEMU nevertheless should not make the assumption that
if __NR_MSGSND, than semtimedop() is present. It could be true, but it is
still just self-imposed belief in QEMU, kernel never guarantied such things.
The alternative way of invoking via IPCV6 (else part of “ifdef
__NR_MSGSND”) should work for MIPS in the present stage of headers and
kernel.
As a side note, perhaps we shoul update kernel headers only off of stable
kernel releases.
Regards,
Aleksandar
- [Qemu-devel] [PULL v3 00/55] s390x update, Cornelia Huck, 2019/05/21
- [Qemu-devel] [PULL v3 46/55] update-linux-headers: handle new header file, Cornelia Huck, 2019/05/21
- [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Cornelia Huck, 2019/05/21
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Philippe Mathieu-Daudé, 2019/05/22
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Cornelia Huck, 2019/05/22
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Laurent Vivier, 2019/05/22
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Cornelia Huck, 2019/05/22
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1,
Aleksandar Markovic <=
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Aleksandar Markovic, 2019/05/22
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Alex Bennée, 2019/05/22
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Cornelia Huck, 2019/05/22
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Aleksandar Markovic, 2019/05/23
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Cornelia Huck, 2019/05/23
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Laurent Vivier, 2019/05/23
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Philippe Mathieu-Daudé, 2019/05/23
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Alex Bennée, 2019/05/23
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Laurent Vivier, 2019/05/23
- Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1, Alex Bennée, 2019/05/22