Re: [Qemu-devel] [PULL v3 47/55] linux headers: update against Linux 5.2-rc1

[Cornelia Huck <cohuck@redhat.com>]

On Wed, 22 May 2019 14:10:39 +0200
Laurent Vivier <laurent@vivier.eu> wrote:

> On 22/05/2019 14:07, Cornelia Huck wrote:
> > On Wed, 22 May 2019 13:47:25 +0200
> > Philippe Mathieu-Daudé <philmd@redhat.com> wrote:
> >   
> >> On 5/21/19 5:28 PM, Cornelia Huck wrote:  
> >>> commit a188339ca5a396acc588e5851ed7e19f66b0ebd9
> >>>
> >>> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
> >>> ---  
> >> [...]  
> >>>   #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?