[PATCH] ipr: RESEND: fix PCI permanent error handler

[PATCH] ipr: RESEND: fix PCI permanent error handler

[Kleber S. Souza]

From: Brian King <brking@linux.vnet.ibm.com>

The ipr driver can hang if it encounters enough PCI errors
to trigger the permanent error handler. The driver will attempt
to initiate a "bringdown" of the adapter and fail all pending
ops back. However, this bringdown is unlike any other bringdown
of the adapter in the code as the driver. In this code path we
end up failing back ops with allow_cmds still set to 1. This results
in some commands, the HCAM commands in particular, getting immediately
re-issued to the adapter on the done call, which results in
an infinite loop in ipr_fail_all_ops. Fix this by setting allow_cmds
to zero in this path. 

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Kleber S. Souza <klebers@linux.vnet.ibm.com>
---

 drivers/scsi/ipr.c |    1 +
 1 file changed, 1 insertion(+)

diff -puN drivers/scsi/ipr.c~ipr_pci_perm_failure_hang
drivers/scsi/ipr.c
---
linux-2.6/drivers/scsi/ipr.c~ipr_pci_perm_failure_hang      2009-04-15
09:25:21.000000000 -0500
+++ linux-2.6-bjking1/drivers/scsi/ipr.c        2009-04-15
09:25:39.000000000 -0500
@@ -6998,6 +6998,7 @@ static void ipr_pci_perm_failure(struct 
                ioa_cfg->sdt_state = ABORT_DUMP;
        ioa_cfg->reset_retries = IPR_NUM_RESET_RELOAD_RETRIES;
        ioa_cfg->in_ioa_bringdown = 1;
+       ioa_cfg->allow_cmds = 0;
        ipr_initiate_ioa_reset(ioa_cfg, IPR_SHUTDOWN_NONE);
        spin_unlock_irqrestore(ioa_cfg->host->host_lock, flags);
 }
_
--

-- 
Kleber S. Souza
IBM Linux Technology Center

Re: [PATCH] ipr: RESEND: fix PCI permanent error handler

[James Bottomley]

On Mon, 2009-04-20 at 13:59 -0300, Kleber S. Souza wrote:
> From: Brian King <brking@linux.vnet.ibm.com>
> 
> The ipr driver can hang if it encounters enough PCI errors
> to trigger the permanent error handler. The driver will attempt
> to initiate a "bringdown" of the adapter and fail all pending
> ops back. However, this bringdown is unlike any other bringdown
> of the adapter in the code as the driver. In this code path we
> end up failing back ops with allow_cmds still set to 1. This results
> in some commands, the HCAM commands in particular, getting immediately
> re-issued to the adapter on the done call, which results in
> an infinite loop in ipr_fail_all_ops. Fix this by setting allow_cmds
> to zero in this path. 
> 
> Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
> Signed-off-by: Kleber S. Souza <klebers@linux.vnet.ibm.com>

OK, now I'm really confused.  Originally this patch was your From: but
had a Brian signoff.  I asked if it shouldn't be acked by him instead
and he responded "correct".

Now you've sent the patch as being his original authorship ... whose
patch is this?

James

Re: [PATCH] ipr: RESEND: fix PCI permanent error handler

[Brian King]

Kleber found the problem, debugged it, and provided a fix to me.
I provided him with an alternate patch to fix it. I'm assuming this
should have been handled by me submitting with my signoff alone and
adding a reported-by tag for Kleber. Sorry for the confusion. Shall
I resend as I just described?

Thanks,

Brian

James Bottomley wrote:
> On Mon, 2009-04-20 at 13:59 -0300, Kleber S. Souza wrote:
>> From: Brian King <brking@linux.vnet.ibm.com>
>>
>> The ipr driver can hang if it encounters enough PCI errors
>> to trigger the permanent error handler. The driver will attempt
>> to initiate a "bringdown" of the adapter and fail all pending
>> ops back. However, this bringdown is unlike any other bringdown
>> of the adapter in the code as the driver. In this code path we
>> end up failing back ops with allow_cmds still set to 1. This results
>> in some commands, the HCAM commands in particular, getting immediately
>> re-issued to the adapter on the done call, which results in
>> an infinite loop in ipr_fail_all_ops. Fix this by setting allow_cmds
>> to zero in this path. 
>>
>> Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
>> Signed-off-by: Kleber S. Souza <klebers@linux.vnet.ibm.com>
> 
> OK, now I'm really confused.  Originally this patch was your From: but
> had a Brian signoff.  I asked if it shouldn't be acked by him instead
> and he responded "correct".
> 
> Now you've sent the patch as being his original authorship ... whose
> patch is this?
> 
> James
> 
> 
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-- 
Brian King
Linux on Power Virtualization
IBM Linux Technology Center

Re: [PATCH] ipr: RESEND: fix PCI permanent error handler

[James Bottomley]

On Mon, 2009-04-20 at 15:18 -0500, Brian King wrote:
> Kleber found the problem, debugged it, and provided a fix to me.
> I provided him with an alternate patch to fix it. I'm assuming this
> should have been handled by me submitting with my signoff alone and
> adding a reported-by tag for Kleber. Sorry for the confusion. Shall
> I resend as I just described?

No, I always thought it was

From: Kleber

Acked-by: you
Signed-off-by: Kleber


I just became confused when the most recent update came through.

James

Re: [PATCH] ipr: RESEND: fix PCI permanent error handler

[James Bottomley]

On Mon, 2009-04-20 at 15:18 -0500, Brian King wrote:
> Kleber found the problem, debugged it, and provided a fix to me.
> I provided him with an alternate patch to fix it. I'm assuming this
> should have been handled by me submitting with my signoff alone and
> adding a reported-by tag for Kleber. Sorry for the confusion. Shall
> I resend as I just described?

The original patch has the tabs replaced by spaces problem, so an
applyable patch correctly attributed would be appreciated.

James

Re: [PATCH] ipr: RESEND: fix PCI permanent error handler

[Kleber S. Souza]

On Mon, 2009-04-27 at 15:38 +0000, James Bottomley wrote:
> On Mon, 2009-04-20 at 15:18 -0500, Brian King wrote:
> > Kleber found the problem, debugged it, and provided a fix to me.
> > I provided him with an alternate patch to fix it. I'm assuming this
> > should have been handled by me submitting with my signoff alone and
> > adding a reported-by tag for Kleber. Sorry for the confusion. Shall
> > I resend as I just described?
> 
> The original patch has the tabs replaced by spaces problem, so an
> applyable patch correctly attributed would be appreciated.
> 
> James
> 
> 

Sending the patch again, now with tabs.

Kleber



The ipr driver can hang if it encounters enough PCI errors
to trigger the permanent error handler. The driver will attempt
to initiate a "bringdown" of the adapter and fail all pending
ops back. However, this bringdown is unlike any other bringdown
of the adapter in the code as the driver. In this code path we
end up failing back ops with allow_cmds still set to 1. This results
in some commands, the HCAM commands in particular, getting immediately
re-issued to the adapter on the done call, which results in
an infinite loop in ipr_fail_all_ops. Fix this by setting allow_cmds
to zero in this path. 

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Kleber S. Souza <klebers@linux.vnet.ibm.com>
---
 drivers/scsi/ipr.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index dd689de..d640359 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -7003,6 +7003,7 @@ static void ipr_pci_perm_failure(struct pci_dev
*pdev)
 		ioa_cfg->sdt_state = ABORT_DUMP;
 	ioa_cfg->reset_retries = IPR_NUM_RESET_RELOAD_RETRIES;
 	ioa_cfg->in_ioa_bringdown = 1;
+	ioa_cfg->allow_cmds = 0;
 	ipr_initiate_ioa_reset(ioa_cfg, IPR_SHUTDOWN_NONE);
 	spin_unlock_irqrestore(ioa_cfg->host->host_lock, flags);
 }
-- 
1.6.0.6



-- 
Kleber S. Souza
IBM Linux Technology Center

Re: [PATCH] ipr: RESEND: fix PCI permanent error handler

[James Bottomley]

On Mon, 2009-05-04 at 10:41 -0300, Kleber S. Souza wrote:
> O@@ -7003,6 +7003,7 @@ static void ipr_pci_perm_failure(struct pci_dev
> *pdev)

OK, so the tabs are fixed, but you mailer still broke this line.  I
fixed it up, but you really need to find a working email tool for next
time.

James