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In-Reply-To: <162569993532.31036.942509527308749032@noble.neil.brown.name>
From:   Daire Byrne <daire@dneg.com>
Date:   Tue, 13 Jul 2021 13:27:33 +0100
Message-ID: <CAPt2mGMToMVpMEhMQ-xHuuyePwSMsXXz6yaG49CfJYPfzU5+KQ@mail.gmail.com>
Subject: Re: [PATCH/rfc v2] NFS: introduce NFS namespaces.
To:     NeilBrown <neilb@suse.de>
Cc:     Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <Anna.Schumaker@netapp.com>,
        linux-nfs <linux-nfs@vger.kernel.org>
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On Thu, 8 Jul 2021 at 00:19, NeilBrown <neilb@suse.de> wrote:
> sorry - my bad..
>
> I think I've found it.  Rather than sending the whole patch, here is the
> incremental fix.  But not clearing this pointer, I risk the value in it
> being freed twice.  That might lead to what you saw.
>
> Thanks,
> NeilBrown
>
>
>
> diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
> index 7c644a31d304..9e34af223ce6 100644
> --- a/fs/nfs/fs_context.c
> +++ b/fs/nfs/fs_context.c
> @@ -1451,6 +1451,7 @@ static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
>         ctx->nfs_server.export_path     = NULL;
>         ctx->nfs_server.hostname        = NULL;
>         ctx->fscache_uniq               = NULL;
> +       ctx->namespace                  = NULL;
>         ctx->clone_data.fattr           = NULL;
>         fc->fs_private = ctx;
>         return 0;
>

Yep, I think that has done the trick. I haven't crashed it with the
same workload yet....

I can do some more thorough testing now. Thanks!

Daire