Re: [Qemu-trivial] [Qemu-devel] [PULL 0/3] Trivial branch patches

[Laurent Vivier]

Le 03/07/2019 à 19:09, Justin Hibbits a écrit :
> On Wed, 3 Jul 2019 18:12:51 +0200
> Laurent Vivier <address@hidden> wrote:
> 
>>> Le 3 juil. 2019 à 17:22, Laurent Vivier <address@hidden> a
>>> écrit :
>>>
>>> Le 03/07/2019 à 16:45, Peter Maydell a écrit :  
>>>> On Tue, 2 Jul 2019 at 13:39, Laurent Vivier <address@hidden>
>>>> wrote:  
>>>>>
>>>>> The following changes since commit
>>>>> 7d0e02405fc02a181319b1ab8681d2f72246b7c6:
>>>>>
>>>>>  Merge remote-tracking branch
>>>>> 'remotes/vivier2/tags/trivial-patches-pull-request' into staging
>>>>> (2019-07-01 17:40:32 +0100)
>>>>>
>>>>> are available in the Git repository at:
>>>>>
>>>>>  git://github.com/vivier/qemu.git tags/trivial-branch-pull-request
>>>>>
>>>>> for you to fetch changes up to
>>>>> 7c955080d40ccc7952a0479bc160f2b048c0af53:
>>>>>
>>>>>  docs/devel/testing: Fix typo in dockerfile path (2019-07-02
>>>>> 10:12:32 +0200)
>>>>>
>>>>> ----------------------------------------------------------------
>>>>> Fix typo, fix sys_cache_info() on FreeBSD/powerpc,
>>>>> change virtio-rng default to urandom
>>>>>
>>>>> ----------------------------------------------------------------  
>>>>
>>>> Hi; this makes 'make check' fail on OSX:
>>>>
>>>> MALLOC_PERTURB_=${MALLOC_PERTURB_:-$(( ${RANDOM:-0} % 255 + 1))}
>>>> tests/test-char -m=quick -k --tap < /dev/null |
>>>> ./scripts/tap-driver.pl --test-name="test-char"
>>>> Assertion failed: ((isize & (isize - 1)) == 0), function
>>>> init_cache_info, file
>>>> /Users/pm215/src/qemu-for-merges/util/cacheinfo.c, line 179.
>>>>
>>>> I guess this is the sys_cache_info change.  
>>>
>>> OK, I will try to reproduce the problem.
>>>
>>> I think before this patch (regarding the kind of change we have
>>> introduced) isize and dsize were always set to 0 and then changed
>>> to 16 in fallback_cache_info()... or perhaps MacOS X sysctlbyname()
>>> needs a long.  
>>
>> It seems MacOS X (x86_64) needs a long:
>>
>> #include <stdio.h>
>> #include <sys/types.h>
>> #include <sys/sysctl.h>
>>
>> int main(void)
>> {
>>         long size;
>>         int ret;
>>         size_t len = sizeof(size);
>>         ret = sysctlbyname("hw.cachelinesize", &size, &len, NULL, 0);
>>         printf("ret %d size 0x%lx\n", ret, size);
>>         return 0;
>> }
>> $ cc -o cachesize cachesize.c
>> $ ./cachesize 
>> ret 0 size 0x40
>>
>> #include <stdio.h>
>> #include <sys/types.h>
>> #include <sys/sysctl.h>
>>
>> int main(void)
>> {
>>         int size;
>>         int ret;
>>         size_t len = sizeof(size);
>>         ret = sysctlbyname("hw.cachelinesize", &size, &len, NULL, 0);
>>         printf("ret %d size 0x%x\n", ret, size);
>>         return 0;
>> }
>> $ cc -o cachesize cachesize.c
>> $ ./cachesize 
>> ret 0 size 0x1737b1d2
>> $ sysctl hw.cachelinesize
>> hw.cachelinesize: 64
>>
>> But man page is not up-to-date:
>>
>> $ uname -r
>> 17.7.0
>> $ man sysctl
>> SYSCTL(8)                 BSD System Manager's Manual
>> SYSCTL(8) …
>>      The string and integer information is summarized below.  For a
>> detailed description of these variable see sysctl(3).
>>
>>      The changeable column indicates whether a process with
>> appropriate privi- lege can change the value.  String and integer
>> values can be set using sysctl.
>>
>>      Name                                        Type
>> Changeable …
>>      hw.cachelinesize                            integer       no
>> …
>>
>> In fact, it is in sysctl(3):
>>
>> SYSCTL(3)                BSD Library Functions Manual
>> SYSCTL(3) …
>>    CTL_HW
>>      The string and integer information available for the CTL_HW
>> level is detailed below.  The changeable column shows whether a
>> process with appropriate privilege may change the value.
>>
>>            Name                         Type          Changeable
>> ...
>>            hw.cachelinesize             int64_t       no
>>
>> I will try to check on MacOS/X ppc and ppc64.
>>
>> Thanks,
>> Laurent
>>
> 
> It's not listed in the man page for ppc(64), but examining the XNU
> source for the version that matches 10.5.8 (last ppc-supporting kernel)
> it's a CTLTYPE_INT.  So, it may be different depending on arch and/or
> OS X version.  Does QEmu even support 10.5.x or Mac OS/ppc* anymore?  I
> had read somewhere that it was unsupported now (2.4.x is the latest one
> in Tigerbrew).

in bsd/sys/sysctl.h, for latest xnu (xnu-4903.221.2, 10.14.1), I have also 
CTLTYPE_INT.

I think the thing to do is change the type only for FreeBSD and keep "long" for 
APPLE.

Thanks,
Laurent