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Date:   Fri, 20 Jul 2018 01:04:31 +0100
From:   Al Viro <viro@ZenIV.linux.org.uk>
To:     Theuns Verwoerd <theuns.verwoerd@alliedtelesis.co.nz>
Cc:     dwmw2@infradead.org, linux-mtd@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] jffs2: Provide jffs2_sync files to track gc POLL
 progress
Message-ID: <20180720000431.GA30522@ZenIV.linux.org.uk>
References: <cover.1532043059.git.theuns.verwoerd@alliedtelesis.co.nz>
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On Fri, Jul 20, 2018 at 11:50:12AM +1200, Theuns Verwoerd wrote:

> +ssize_t jffs2_sync_file_read(struct file *f,
> +	      char __user *b, size_t len, loff_t *ofs)
> +{
> +	struct jffs2_sb_info *c = file_inode(f)->i_private;
> +
> +	while (c->tidemark)
> +		schedule();
> +
> +	return 0;
> +}

Brilliant.  So when that gets called with c->tidemark being true and
need_resched() - false, we shall...

Bonus question: what happens if that is called after that jffs2_sb_info
gets freed?

--
It Doesn't Need To Make Sense - It's For Security Purposes.