From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.glaze.se ([212.209.188.162] helo=rocket.glaze.se) by canuck.infradead.org with esmtp (Exim 4.52 #1 (Red Hat Linux)) id 1EMu1L-0006Me-Jo for linux-mtd@lists.infradead.org; Tue, 04 Oct 2005 17:08:41 -0400 Received: from IBMJP (unknown [10.42.1.6]) by rocket.glaze.se (Postfix) with ESMTP id 1DE0737645D for ; Tue, 4 Oct 2005 22:47:26 +0200 (CEST) From: "Jan Pedersen" To: Date: Tue, 4 Oct 2005 22:47:29 +0200 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-Id: <20051004204726.1DE0737645D@rocket.glaze.se> Subject: [patch] cfi: prevent kernel panic with cfi flash List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , When using the cfi (common flash interface) driver, every word written to the flash chips is followed by a operation complete poll. This poll is intended to have a timeout of 1 ms. However this timeout is calculated by HZ/1000, which happends to be 0 because HZ < 1000. The result of this is that there will be just one poll for operation complete. If this single poll fails, the kernel panics. This patch increases this timeout to HZ (1 second). This is far more than needed, but is preferred over a panic. This fix is well tested and completely avoids the panic. Signed-off-by: Jan Pedersen --- diff -Naur linux-2.4.31.org/drivers/mtd/chips/cfi_cmdset_0002.c linux-2.4.31/drivers/mtd/chips/cfi_cmdset_0002.c --- linux-2.4.31.org/drivers/mtd/chips/cfi_cmdset_0002.c 2004-11-17 06:54:21.000000000 -0500 +++ linux-2.4.31/drivers/mtd/chips/cfi_cmdset_0002.c 2005-08-22 12:14:17.000000000 -0400 @@ -510,7 +510,7 @@ or tells us why it failed. */ dq6 = CMD(1<<6); dq5 = CMD(1<<5); - timeo = jiffies + (HZ/1000); /* setting timeout to 1ms for now */ + timeo = jiffies + (HZ); /* setting timeout to 1s for now */ oldstatus = cfi_read(map, adr); status = cfi_read(map, adr);