Re: buildworld: lib/libc: install: short write to libc.so.7.debug: [_libinstall] Error code 71

On 22/11/2020 18:06, Kyle Evans wrote:
> On Sun, Nov 22, 2020 at 6:00 AM Dimitry Andric <dim_at_freebsd.org> wrote:
>> I'd guess it's an unintended side-effect of
>> https://svnweb.freebsd.org/base?view=revision&revision=366697
>> ("install(1): Avoid unncessary fstatfs() calls and use mmap() based on
>> size").
>>
> 
> Almost certainly -- before, we would never attempt to mmap() on ZFS.
> 
> Tossing arichardson_at_ into CC as the committer
> Tossing mmacy_at_ and freqlabs_at_ into CC as ZFS folks
> 
> Looking through sys/contrib/openzfs, there's special handling for mmap
> on linux because it bypasses the page cache and relies on caching in
> ARC. AFAICT the FreeBSD side seems to handle write() to mmap'd
> regions, but doesn't do anything with VOP_MMAPPED which might be
> needed to sync the file when it's mmap'd for reading like this. My
> understanding of how this is supposed to actually work on FreeBSD is
> limited, though, so I defer...

Last time I checked mmap worked correctly with ZFS, that was before the switch.
Perhaps, there was an undetected issue -- this can be tested, e.g., by applying
the install change to stable/12.
Perhaps, the ZFS switch came with a regression.


-- 
Andriy Gapon