From: Richard Chang <richardycc@google.com>
To: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Minchan Kim <minchan@kernel.org>,
Brian Geffon <bgeffon@google.com>,
linux-block@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH] zram: do not slot_free() written-back slots
Date: Thu, 19 Mar 2026 14:47:07 +0800 [thread overview]
Message-ID: <CALC_0q_2meJ7T8gvij5oR=idy9hn5rMC_RQhCbePJFVBOOd0Tw@mail.gmail.com> (raw)
In-Reply-To: <abt1dsjsT9826Ewy@google.com>
I think we also need clear_slot_flag(zram, index, ZRAM_PP_SLOT)
On Thu, Mar 19, 2026 at 12:06 PM Sergey Senozhatsky
<senozhatsky@chromium.org> wrote:
>
> As a side note:
>
> On (26/03/19 12:44), Sergey Senozhatsky wrote:
> > - slot_free(zram, index);
> [..]
> > - if (huge)
> > - set_slot_flag(zram, index, ZRAM_HUGE);
>
> Original code had a bug. slot_free() would decrement ->huge_pages,
> then writeback completion would restore the HUGE flag, so when slot
> would get freed for real slot_free() would decrement ->huge_pages
> again, leading to underflow.
next prev parent reply other threads:[~2026-03-19 6:47 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-19 3:44 Sergey Senozhatsky
2026-03-19 4:05 ` Sergey Senozhatsky
2026-03-19 6:47 ` Richard Chang [this message]
2026-03-19 7:21 ` Sergey Senozhatsky
2026-03-19 17:59 ` Minchan Kim
2026-03-19 19:43 ` Minchan Kim
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