Re: [Qemu-devel] [PATCH] linux-user: fix __NR_semtimedop undeclared error

[Aleksandar Markovic]

On May 28, 2019 6:25 PM, "Laurent Vivier" <address@hidden> wrote:
>
> On 23/05/2019 19:54, Laurent Vivier wrote:
>>
>> In current code, __NR_msgrcv and__NR_semtimedop are supposed to be
>> defined if __NR_msgsnd is defined.
>>
>> But linux headers 5.2-rc1 for MIPS define __NR_msgsnd without defining
>> __NR_semtimedop and it breaks the QEMU build.
>>
>> __NR_semtimedop is defined in asm-mips/unistd_n64.h and
asm-mips/unistd_n32.h
>> but not in asm-mips/unistd_o32.h.
>>
>> Commit d9cb4336159a ("linux headers: update against Linux 5.2-rc1") has
>> updated asm-mips/unistd_o32.h and added __NR_msgsnd but not
__NR_semtimedop.
>> It introduces __NR_semtimedop_time64 instead.
>>
>> This patch fixes the problem by checking for each __NR_XXX symbol
>> before defining the corresponding syscall.
>>
>> Fixes: d9cb4336159a ("linux headers: update against Linux 5.2-rc1")
>> Reported-by: Philippe Mathieu-Daudé <address@hidden>
>> Signed-off-by: Laurent Vivier <address@hidden>
>> ---
>>   linux-user/syscall.c | 24 ++++++++++++++++--------
>>   1 file changed, 16 insertions(+), 8 deletions(-)
>
>
> This only fixes the problem at build time, but the changes in the kernel
headers introduce also a regression at execution time:
>
> if the host kernel doesn't implement the syscall, the syscall fails
(ENOSYS) whereas it was working before because it was using ipc() instead.
I have this problem with a Fedora 28 on ppc64 (5.0.16-100.fc28.ppc64) (LTP
test msgctl07).
>
> I'm preparing a fix.
>

OK, great that you found this behavior, thanks. Just want to tell you that
meanwhile the original code of this patch got integrated into main source
tree.

Regards,
Aleksandar

> Thanks,
> Laurent