[PATCH] aacraid: fix shutdown handler to also disable interrupts.

["Salyzyn, Mark" <mark_salyzyn@adaptec.com>]

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Moves quiesce, thread and interrupt shutdown into aacraid drivers'
.shutdown handler. This fix to the aac_shutdown handler will remove the
superfluous reset of the adapter during a (clean) kexec.

This fix may mitigate the active investigation 'kexec and aacraid
broken' but it is unlikely to affect the root cause (issue likely
present in both kexec and kdump). This patch reduces the chance the
problem will occur with a kexec. The fix for root cause is currently
expected to be the minimum value check to the aacraid.startup_timeout
driver variable after an adapter reset within aacraid_commit_reset.patch
submitted on 05/22/2007 and awaiting testing by Yinghai to confirm.

This attached patch is against current scsi-misc-2.6

ObligatoryDisclaimer: Please accept my condolences regarding Outlook's
handling of patch attachments.

Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>

Sincerely -- Mark Salyzyn

> -----Original Message-----
> From: linux-scsi-owner@vger.kernel.org 
> [mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Salyzyn, Mark
> Sent: Wednesday, May 30, 2007 10:31 AM
> To: vgoyal@in.ibm.com
> Cc: Andrew Morton; Yinghai Lu; Eric W. Biederman; Linux 
> Kernel Mailing List; linux-scsi@vger.kernel.org; Michal Piotrowski
> Subject: RE: kexec and aacraid broken
> 
> Vivek Goyal [mailto:vgoyal@in.ibm.com] writes:
> > So most likely if we start disabling the interrupts
> > in .shutdown routine we might skip resetting adapter
> > on every kexec without any side affects?
> 
> Not that simple. The .shutdown would need to perform more resource
> cleanups of the .remove call to prevent side effects. I need to move
> some of the .remove activity into the .shutdown handler to 
> make sure the
> adapter is quiesced.
> 
> I will hold off on submitting any of these changes until they are
> evaluated and tested; I am waiting for feedback from Yinghai on the
> other mitigations that I feel are closer to the root cause.
> 
> Sincerely -- Mark Salyzyn

[-- Attachment #2: aacraid_shutdown.patch --]
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diff -ru a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
--- a/drivers/scsi/aacraid/linit.c	2007-05-30 11:00:36.619831521 -0400
+++ b/drivers/scsi/aacraid/linit.c	2007-05-30 11:04:35.325867212 -0400
@@ -859,6 +859,14 @@
 	.emulated                       = 1,
 };
 
+static void __aac_shutdown(struct aac_dev * aac)
+{
+	kthread_stop(aac->thread);
+	aac_send_shutdown(aac);
+	aac_adapter_disable_int(aac);
+	free_irq(aac->pdev->irq, aac);
+}
+
 static int __devinit aac_probe_one(struct pci_dev *pdev,
 		const struct pci_device_id *id)
 {
@@ -1011,10 +1019,7 @@
 	return 0;
 
  out_deinit:
-	kthread_stop(aac->thread);
-	aac_send_shutdown(aac);
-	aac_adapter_disable_int(aac);
-	free_irq(pdev->irq, aac);
+	__aac_shutdown(aac);
  out_unmap:
 	aac_fib_map_free(aac);
 	pci_free_consistent(aac->pdev, aac->comm_size, aac->comm_addr, aac->comm_phys);
@@ -1034,7 +1039,8 @@
 {
 	struct Scsi_Host *shost = pci_get_drvdata(dev);
 	struct aac_dev *aac = (struct aac_dev *)shost->hostdata;
-	aac_send_shutdown(aac);
+	scsi_block_requests(shost);
+	__aac_shutdown(aac);
 }
 
 static void __devexit aac_remove_one(struct pci_dev *pdev)
@@ -1044,16 +1050,12 @@
 
 	scsi_remove_host(shost);
 
-	kthread_stop(aac->thread);
-
-	aac_send_shutdown(aac);
-	aac_adapter_disable_int(aac);
+	__aac_shutdown(aac);
 	aac_fib_map_free(aac);
 	pci_free_consistent(aac->pdev, aac->comm_size, aac->comm_addr,
 			aac->comm_phys);
 	kfree(aac->queues);
 
-	free_irq(pdev->irq, aac);
 	aac_adapter_ioremap(aac, 0);
 	
 	kfree(aac->fibs);