From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH #upstream-fixes] libata: don't normalize UNKNOWN to NONE after reset Date: Tue, 08 Jan 2008 20:26:12 +0900 Message-ID: <47835DD4.4000609@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from wa-out-1112.google.com ([209.85.146.180]:39910 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754039AbYAHL0U (ORCPT ); Tue, 8 Jan 2008 06:26:20 -0500 Received: by wa-out-1112.google.com with SMTP id v27so13140644wah.23 for ; Tue, 08 Jan 2008 03:26:19 -0800 (PST) Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik , IDE/ATA development list , Robert Hancock After non-classifying reset, ehc->classes[] could contain ATA_DEV_UNKNOWN which used to be normalized to ATA_DEV_NONE for consistency. However, this causes unfortunate side effect for drivers which have non-classifying hardresets (e.g. sata_nv) by making hardreset report ATA_DEV_NONE for non-classifying resets and thus makes EH believe that the port is unoccupied and recovery can be skipped. The end result is that after a device is swapped with another one, the new device isn't attached after the old one is detached. This patch makes ata_eh_reset() not normalize UNKNOWN to NONE after non-classifying resets. This fixes the above problem. As UNKNOWN and NONE are handled differently by only EH hotplug logic, this doesn't cause other behavior changes. Signed-off-by: Tejun Heo Cc: Robert Hancock --- Robert, missing new device was a bug in core EH logic not sata_nv. BTW, I did quite a few hotplug tests with adma=0 and it works just fine. No lock up. drivers/ata/libata-eh.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index f0124a8..e7757dd 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -2157,13 +2157,11 @@ int ata_eh_reset(struct ata_link *link, int classify, if (ata_link_offline(link)) continue; - /* apply class override and convert UNKNOWN to NONE */ + /* apply class override */ if (lflags & ATA_LFLAG_ASSUME_ATA) classes[dev->devno] = ATA_DEV_ATA; else if (lflags & ATA_LFLAG_ASSUME_SEMB) classes[dev->devno] = ATA_DEV_SEMB_UNSUP; /* not yet */ - else if (classes[dev->devno] == ATA_DEV_UNKNOWN) - classes[dev->devno] = ATA_DEV_NONE; } /* record current link speed */