Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755123Ab3JUJBU (ORCPT ); Mon, 21 Oct 2013 05:01:20 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:39838 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754459Ab3JUIxG (ORCPT ); Mon, 21 Oct 2013 04:53:06 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org Date: Mon, 21 Oct 2013 09:46:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 128/149] Revert "zram: use zram->lock to protect zram_free_page() in swap free notify path" In-Reply-To: X-SA-Exim-Connect-IP: 212.20.242.100 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1672 Lines: 47 3.2.52-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Ben Hutchings This reverts commit 9e443904906ca2b5b3ae71f34ac4a4fa6905623e, which was commit 57ab048532c0d975538cebd4456491b5c34248f4 upstream. Taking the semaphore here leads to sleeping in atomic context. This was fixed in mainline commit a0c516cbfc74 ("zram: don't grab mutex in zram_slot_free_noity") but that is too difficult to backport. Signed-off-by: Ben Hutchings --- --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -709,9 +709,7 @@ static void zram_slot_free_notify(struct struct zram *zram; zram = bdev->bd_disk->private_data; - down_write(&zram->lock); zram_free_page(zram, index); - up_write(&zram->lock); zram_stat64_inc(zram, &zram->stats.notify_free); } --- a/drivers/staging/zram/zram_drv.h +++ b/drivers/staging/zram/zram_drv.h @@ -107,9 +107,8 @@ struct zram { void *compress_buffer; struct table *table; spinlock_t stat64_lock; /* protect 64-bit stats */ - struct rw_semaphore lock; /* protect compression buffers, table, - * 32bit stat counters against concurrent - * notifications, reads and writes */ + struct rw_semaphore lock; /* protect compression buffers and table + * against concurrent read and writes */ struct request_queue *queue; struct gendisk *disk; int init_done; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/