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Date: Thu, 19 Mar 2026 12:43:16 -0700
From: Minchan Kim <minchan@kernel.org>
To: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Brian Geffon <bgeffon@google.com>,
	Richard Chang <richardycc@google.com>, linux-block@vger.kernel.org,
	linux-mm@kvack.org
Subject: Re: [PATCH] zram: do not slot_free() written-back slots
Message-ID: <abxR1Pm-JksGZYly@google.com>
References: <20260319034912.1894770-1-senozhatsky@chromium.org>
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In-Reply-To: <20260319034912.1894770-1-senozhatsky@chromium.org>

On Thu, Mar 19, 2026 at 12:44:56PM +0900, Sergey Senozhatsky wrote:
> slot_free() basically completely resets the slots by clearing
> all of its flags and attributes.  While zram_writeback_complete()
> restores some of flags back (those that are necessary for async
> read decompression) we still lose a lot of slot's metadata.  For
> example, slot's ac-time, or ZRAM_INCOMPRESSIBLE.
> 
> Do not slot_free() on writeback, instead clear only those
> flags/attrs that we need to clear.
> 
> Fixes: d38fab605c667 ("zram: introduce compressed data writeback")
> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>

Acked-by: Minchan Kim <minchan@kernel.org>

With small nit about the description in previous comment,