Date:   Tue, 14 Feb 2023 20:16:38 +0900
From:   Dominique Martinet <asmadeus@codewreck.org>
To:     Christian Schoenebeck <linux_oss@crudebyte.com>
Cc:     v9fs-developer@lists.sourceforge.net,
        Eric Van Hensbergen <ericvh@gmail.com>,
        Latchesar Ionkov <lucho@ionkov.net>,
        linux-kernel@vger.kernel.org, Jens Axboe <axboe@kernel.dk>,
        Pengfei Xu <pengfei.xu@intel.com>
Subject: Re: [PATCH 0/5] Take 3 at async RPCs and no longer looping forever
 on signals
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Christian Schoenebeck wrote on Tue, Feb 14, 2023 at 10:34:36AM +0100:
> > Ugh! thanks for the test, I'm not making much sense of the trace (folio
> > wait bit means some background write isn't happening when flushing
> > before the setattr?) but I'll try to reproduce and have a look
> > today/tomorrow
> 
> Yes, apparently it tries to write dirty pages of the mapped file and keeps
> hanging there [fs/9p/vfs_inode_dotl.c:586]:

Yeah, it'd help to get the trace of the thread actually trying to do the
IO, if it still exists.
I had some hangs in the check that there are no flush in flight at some
point, and I thought I fixed that, but I can't really see anywhere else
that'd start hanging with this... it'll be clearer if I can reproduce.


Anyway, I found another bug, just running ./configure on a random project
(picked coreutils tarball) fails with interrupted system call ?!

checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking whether make supports nested variables... (cached) yes
checking for gcc... gcc
./configure: line 6385: can't create conftest.c: Interrupted system call
checking whether the C compiler works... no
sed: can't read conftest.c: No such file or directory
configure: error: in `/mnt/coreutils-9.1':
configure: error: C compiler cannot create executables
See `config.log' for more details


This obviously doesn't happen if I run with `sh -x configure`, but
through execsnoop I caught it's just calling 'gcc conftest.c' and
there's nothing special in here... But it doesn't happen without these
patches, so I get something to dig at first.
With a bit of luck it's the same root cause...

-- 
Dominique