diff mbox

Niagara2 & Could not register hvapi ATU err=-22

Message ID 5689d5bc-4657-4d60-34fa-02bb6b3eb58a@oracle.com
State RFC
Delegated to: David Miller
Headers show

Commit Message

Tushar Dave Aug. 15, 2017, 10:07 p.m. UTC 
On 08/15/2017 07:42 AM, Meelis Roos wrote:
> I noticed that on Niagara2, dmesg has a red error about ATU
> registration:
> 
> [    4.579231] pci_sun4v: Could not register hvapi ATU err=-22
> 
> This is preceded by info line
> [    4.578073] pci_sun4v: Registered hvapi major[1] minor[0]
> 
> As I understand, there is no ATU on Niagara1 & Niagara2 sun4v platforms,
> so there is no point in trying to log an error to dmesg in that case?
You are right.
IMO, we should not log ATU hvapi registration failure message at all. 
Unlike PCI hvapi, ATU hvapi registration failure is not *hard error*.
Even if ATU hvapi registration fails (on system with ATU or without ATU) 
system continues with legacy IOMMU.
So I think log message only when ATU is registered successfully.

                                 vatu_major, vatu_minor);


-Tushar
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Comments

David Miller Aug. 15, 2017, 11:31 p.m. UTC | #1 
From: Tushar Dave <tushar.n.dave@oracle.com>
Date: Tue, 15 Aug 2017 15:07:35 -0700

> 
> 
> On 08/15/2017 07:42 AM, Meelis Roos wrote:
>> I noticed that on Niagara2, dmesg has a red error about ATU
>> registration:
>> [    4.579231] pci_sun4v: Could not register hvapi ATU err=-22
>> This is preceded by info line
>> [    4.578073] pci_sun4v: Registered hvapi major[1] minor[0]
>> As I understand, there is no ATU on Niagara1 & Niagara2 sun4v
>> platforms,
>> so there is no point in trying to log an error to dmesg in that case?
> You are right.
> IMO, we should not log ATU hvapi registration failure message at
> all. Unlike PCI hvapi, ATU hvapi registration failure is not *hard
> error*.
> Even if ATU hvapi registration fails (on system with ATU or without
> ATU) system continues with legacy IOMMU.
> So I think log message only when ATU is registered successfully.

Please submit this formally.

Thank you.
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diff mbox

Patch

diff --git a/arch/sparc/kernel/pci_sun4v.c b/arch/sparc/kernel/pci_sun4v.c
index f10e2f7..9ebebf1 100644
--- a/arch/sparc/kernel/pci_sun4v.c
+++ b/arch/sparc/kernel/pci_sun4v.c
@@ -1266,8 +1266,6 @@  static int pci_sun4v_probe(struct platform_device *op)
                          * ATU group, but ATU hcalls won't be available.
                          */
                         hv_atu = false;
-                       pr_err(PFX "Could not register hvapi ATU err=%d\n",
-                              err);
                 } else {
                         pr_info(PFX "Registered hvapi ATU major[%lu] 
minor[%lu]\n",