Re: [PATCH] iommu/amd: fix missing tag from dev_err message

From: Walter Harms
Date: Tue Jul 03 2018 - 12:57:19 EST



Am 03.07.2018 18:38, schrieb Joe Perches:
> On Tue, 2018-07-03 at 11:27 -0500, Hook, Gary wrote:
>> On 7/3/2018 11:24 AM, Colin Ian King wrote:
>>> On 03/07/18 17:21, Hook, Gary wrote:
>>>> On 7/3/2018 10:55 AM, Joe Perches wrote:
>>>>> On Tue, 2018-07-03 at 07:56 -0500, Gary R Hook wrote:
>>>>>> On 07/03/2018 05:07 AM, Joe Perches wrote:
>>>>>>> On Tue, 2018-07-03 at 07:40 +0100, Colin King wrote:
>>>>>>>> Currently tag is being assigned but not used, it is missing from
>>>>>>>> the dev_err message, so add it in.
>>>>>>>>
>>>>>>>> Cleans up clang warning:
>>>>>>>> warning: variable 'tag' set but not used [-Wunused-but-set-variable]
>>>>>>>
>>>>>>> []
>>>>>>>> diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
>>>>>>>
>>>>>>> []
>>>>>>>> @@ -616,9 +616,9 @@ static void iommu_print_event(struct amd_iommu
>>>>>>>> *iommu, void *__evt)
>>>>>>>> pasid = ((event[0] >> 16) & 0xFFFF)
>>>>>>>> | ((event[1] << 6) & 0xF0000);
>>>>>>>> tag = event[1] & 0x03FF;
>>>>>>>> - dev_err(dev, "INVALID_PPR_REQUEST device=%02x:%02x.%x
>>>>>>>> pasid=0x%05x address=0x%016llx flags=0x%04x]\n",
>>>>>>>> + dev_err(dev, "INVALID_PPR_REQUEST device=%02x:%02x.%x
>>>>>>>> pasid=0x%05x address=0x%016llx flags=0x%04x tag=0x%03x]\n",
>>>>>>>> PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
>>>>>>>> - pasid, address, flags);
>>>>>>>> + pasid, address, flags, tag);
>>>>>>>
>>>>>>> Seems to have a superfluous ] that should be removed.
>>>>>>
>>>>>> Yeah, I pretty much messed up all of the log messages in that function.
>>>>>> My apologies. I'll create a patch for that problem; it shouldn't be
>>>>>> fixed here.
>>>>
>>>> Well, no, I misremembered. The extraneous square brace has been there
>>>> forever. Needs fixin', though.
>>>>
>>>
>>> The opening square bracket is much earlier:
>>>
>>> dev_err(dev, "AMD-Vi: Event logged [");
>>>
>>> ..and all the subsequent dev_err messages have the trailing square bracket.
>>
>> Gah! Mystery solved. I'd forgotten about that.
>>
>> "Never mind."
>>

It is only cosmetics but even the author got lost about the loose bracket.
I would suggest to remove all the brackets or if needed to move the [ in the
message. We have enought memory this days.

> - printk(KERN_ERR "AMD-Vi: Event logged [");
> + dev_err(dev, "AMD-Vi: Event logged [");

just my 2 cents,

re,
wh

>
> It stems from the misconversion from printk to dev_err
>
> The initial dev_err is fine but all the dev_err uses
> in the switch/case should use pr_cont, not dev_err
>
> (there's a suggested patch below this commit reference)
>
> ---
>>From 90ca3859f5ea90050d00e695355934b37357e7bb Mon Sep 17 00:00:00 2001
> From: Gary R Hook <gary.hook@xxxxxxx>
> Date: Thu, 8 Mar 2018 18:34:41 -0600
> Subject: [PATCH] iommu/amd: Use dev_err to send events to the system log
>
> Remove printk and use a more preferable error logging function.
>
> Signed-off-by: Gary R Hook <gary.hook@xxxxxxx>
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
> ---
> drivers/iommu/amd_iommu.c | 55
> ++++++++++++++++++++++++++++---------------------------
> 1 file changed, 28 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
> index 997a947ddc3b..4cd19f93ca15 100644
> --- a/drivers/iommu/amd_iommu.c
> +++ b/drivers/iommu/amd_iommu.c
> @@ -547,6 +547,7 @@ static void amd_iommu_report_page_fault(u16 devid, u16
> domain_id,
>
> static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
> {
> + struct device *dev = iommu->iommu.dev;
> int type, devid, domid, flags;
> volatile u32 *event = __evt;
> int count = 0;
> @@ -573,53 +574,53 @@ static void iommu_print_event(struct amd_iommu *iommu,
> void *__evt)
> amd_iommu_report_page_fault(devid, domid, address, flags);
> return;
> } else {
> - printk(KERN_ERR "AMD-Vi: Event logged [");
> + dev_err(dev, "AMD-Vi: Event logged [");
> }
>
> switch (type) {
> case EVENT_TYPE_ILL_DEV:
> - printk("ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x "
> - "address=0x%016llx flags=0x%04x]\n",
> - PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> - address, flags);
> + dev_err(dev, "ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x "
> + "address=0x%016llx flags=0x%04x]\n",
> + PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> + address, flags);
>
> etc...
>
> so this could be:
>
> ---
> drivers/iommu/amd_iommu.c | 23 +++++++++++------------
> 1 file changed, 11 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
> index 596b95c50051..f78cfa094301 100644
> --- a/drivers/iommu/amd_iommu.c
> +++ b/drivers/iommu/amd_iommu.c
> @@ -572,43 +572,42 @@ static void iommu_print_event(struct amd_iommu *iommu,
> void *__evt)
> if (type == EVENT_TYPE_IO_FAULT) {
> amd_iommu_report_page_fault(devid, pasid, address, flags);
> return;
> - } else {
> - dev_err(dev, "AMD-Vi: Event logged [");
> }
>
> + dev_err(dev, "AMD-Vi: Event logged [");
> +
> switch (type) {
> case EVENT_TYPE_ILL_DEV:
> - dev_err(dev, "ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x pasid=0x%05x
> address=0x%016llx flags=0x%04x]\n",
> + pr_cont("ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x pasid=0x%05x
> address=0x%016llx flags=0x%04x]\n",
> PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> pasid, address, flags);
> dump_dte_entry(devid);
> break;
> case EVENT_TYPE_DEV_TAB_ERR:
> - dev_err(dev, "DEV_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
> - "address=0x%016llx flags=0x%04x]\n",
> + pr_cont("DEV_TAB_HARDWARE_ERROR device=%02x:%02x.%x address=0x%016llx
> flags=0x%04x]\n",
> PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> address, flags);
> break;
> case EVENT_TYPE_PAGE_TAB_ERR:
> - dev_err(dev, "PAGE_TAB_HARDWARE_ERROR device=%02x:%02x.%x domain=0x%04x
> address=0x%016llx flags=0x%04x]\n",
> + pr_cont("PAGE_TAB_HARDWARE_ERROR device=%02x:%02x.%x domain=0x%04x
> address=0x%016llx flags=0x%04x]\n",
> PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> pasid, address, flags);
> break;
> case EVENT_TYPE_ILL_CMD:
> - dev_err(dev, "ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address);
> + pr_cont("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address);
> dump_command(address);
> break;
> case EVENT_TYPE_CMD_HARD_ERR:
> - dev_err(dev, "COMMAND_HARDWARE_ERROR address=0x%016llx flags=0x%04x]\n",
> + pr_cont("COMMAND_HARDWARE_ERROR address=0x%016llx flags=0x%04x]\n",
> address, flags);
> break;
> case EVENT_TYPE_IOTLB_INV_TO:
> - dev_err(dev, "IOTLB_INV_TIMEOUT device=%02x:%02x.%x address=0x%016llx]\n",
> + pr_cont("IOTLB_INV_TIMEOUT device=%02x:%02x.%x address=0x%016llx]\n",
> PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> address);
> break;
> case EVENT_TYPE_INV_DEV_REQ:
> - dev_err(dev, "INVALID_DEVICE_REQUEST device=%02x:%02x.%x pasid=0x%05x
> address=0x%016llx flags=0x%04x]\n",
> + pr_cont("INVALID_DEVICE_REQUEST device=%02x:%02x.%x pasid=0x%05x
> address=0x%016llx flags=0x%04x]\n",
> PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> pasid, address, flags);
> break;
> @@ -616,12 +615,12 @@ static void iommu_print_event(struct amd_iommu *iommu,
> void *__evt)
> pasid = ((event[0] >> 16) & 0xFFFF)
> | ((event[1] << 6) & 0xF0000);
> tag = event[1] & 0x03FF;
> - dev_err(dev, "INVALID_PPR_REQUEST device=%02x:%02x.%x pasid=0x%05x
> address=0x%016llx flags=0x%04x]\n",
> + pr_cont("INVALID_PPR_REQUEST device=%02x:%02x.%x pasid=0x%05x
> address=0x%016llx flags=0x%04x]\n",
> PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> pasid, address, flags);
> break;
> default:
> - dev_err(dev, "UNKNOWN event[0]=0x%08x event[1]=0x%08x event[2]=0x%08x
> event[3]=0x%08x\n",
> + pr_cont("UNKNOWN event[0]=0x%08x event[1]=0x%08x event[2]=0x%08x
> event[3]=0x%08x\n",
> event[0], event[1], event[2], event[3]);
> }
>
> --
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