From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qc0-f201.google.com ([209.85.216.201]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WSb68-0006iI-V3 for linux-mtd@lists.infradead.org; Tue, 25 Mar 2014 23:49:38 +0000 Received: by mail-qc0-f201.google.com with SMTP id c9so170366qcz.0 for ; Tue, 25 Mar 2014 16:49:12 -0700 (PDT) From: Gwendal Grignou To: axboe@kernel.dk, ulf.hansson@linaro.org Subject: [PATCH 1/4] Limit max_discard_sectors to UINT_MAX>>9 Date: Tue, 25 Mar 2014 16:48:23 -0700 Message-Id: <1395791307-23727-2-git-send-email-gwendal@chromium.org> In-Reply-To: <1395791307-23727-1-git-send-email-gwendal@chromium.org> References: <1395791307-23727-1-git-send-email-gwendal@chromium.org> Cc: linux-mmc@vger.kernel.org, Gwendal Grignou , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , max_discard_sectors can not be larger than UINT_MAX>>9, otherwise, there is a risk that discard requests would be merged into a request larger than 4GB. Signed-off-by: Gwendal Grignou --- drivers/block/nbd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 2dc3b51..f30128b 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -859,7 +859,7 @@ static int __init nbd_init(void) */ queue_flag_set_unlocked(QUEUE_FLAG_NONROT, disk->queue); disk->queue->limits.discard_granularity = 512; - disk->queue->limits.max_discard_sectors = UINT_MAX; + disk->queue->limits.max_discard_sectors = UINT_MAX >> 9; disk->queue->limits.discard_zeroes_data = 0; blk_queue_max_hw_sectors(disk->queue, 65536); disk->queue->limits.max_sectors = 256; -- 1.9.1.423.g4596e3a