Handling possible internal errors by just emitting a (debug-build-only)
log message can't be quite enough. Return error codes in those cases,
and have the caller propagate those up.
Drop a pointless return path, rather than "inventing" an error code for
it.
While touching the function declarator anyway also constify its first
parameter.
Fixes: 476bbccc811c ("VT-d: fix MSI source-id of interrupt remapping")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/drivers/passthrough/vtd/intremap.c
+++ b/xen/drivers/passthrough/vtd/intremap.c
@@ -436,15 +436,13 @@ void cf_check io_apic_write_remap_rte(
__ioapic_write_entry(apic, pin, true, old_rte);
}
-static void set_msi_source_id(struct pci_dev *pdev, struct iremap_entry *ire)
+static int set_msi_source_id(const struct pci_dev *pdev,
+ struct iremap_entry *ire)
{
u16 seg;
u8 bus, devfn, secbus;
int ret;
- if ( !pdev || !ire )
- return;
-
seg = pdev->seg;
bus = pdev->bus;
devfn = pdev->devfn;
@@ -485,16 +483,21 @@ static void set_msi_source_id(struct pci
PCI_BDF(bus, devfn));
}
else
+ {
dprintk(XENLOG_WARNING VTDPREFIX,
"d%d: no upstream bridge for %pp\n",
pdev->domain->domain_id, &pdev->sbdf);
+ return -ENXIO;
+ }
break;
default:
dprintk(XENLOG_WARNING VTDPREFIX, "d%d: unknown(%u): %pp\n",
pdev->domain->domain_id, pdev->type, &pdev->sbdf);
- break;
- }
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
}
static int msi_msg_to_remap_entry(
@@ -509,7 +512,12 @@ static int msi_msg_to_remap_entry(
bool alloc = false;
if ( pdev )
- set_msi_source_id(pdev, &new_ire);
+ {
+ int rc = set_msi_source_id(pdev, &new_ire);
+
+ if ( rc )
+ return rc;
+ }
else
set_hpet_source_id(msi_desc->hpet_id, &new_ire);On 13/03/2025 1:34 pm, Jan Beulich wrote:
> Handling possible internal errors by just emitting a (debug-build-only)
> log message can't be quite enough. Return error codes in those cases,
> and have the caller propagate those up.
>
> Drop a pointless return path, rather than "inventing" an error code for
> it.
>
> While touching the function declarator anyway also constify its first
> parameter.
>
> Fixes: 476bbccc811c ("VT-d: fix MSI source-id of interrupt remapping")
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>, although...
>
> --- a/xen/drivers/passthrough/vtd/intremap.c
> +++ b/xen/drivers/passthrough/vtd/intremap.c
> @@ -436,15 +436,13 @@ void cf_check io_apic_write_remap_rte(
> __ioapic_write_entry(apic, pin, true, old_rte);
> }
>
> -static void set_msi_source_id(struct pci_dev *pdev, struct iremap_entry *ire)
> +static int set_msi_source_id(const struct pci_dev *pdev,
> + struct iremap_entry *ire)
> {
> u16 seg;
> u8 bus, devfn, secbus;
> int ret;
>
> - if ( !pdev || !ire )
> - return;
> -
> seg = pdev->seg;
> bus = pdev->bus;
> devfn = pdev->devfn;
> @@ -485,16 +483,21 @@ static void set_msi_source_id(struct pci
> PCI_BDF(bus, devfn));
> }
> else
> + {
> dprintk(XENLOG_WARNING VTDPREFIX,
> "d%d: no upstream bridge for %pp\n",
> pdev->domain->domain_id, &pdev->sbdf);
as you're doing cleanup, %pd here? Given DOM_IO for quarantine, I think
it's more likely now than it used to be.
> + return -ENXIO;
> + }
> break;
>
> default:
> dprintk(XENLOG_WARNING VTDPREFIX, "d%d: unknown(%u): %pp\n",
> pdev->domain->domain_id, pdev->type, &pdev->sbdf);
Here too. Also, the "unknown(%u)" is less than ideal. "%pd: %pp
unknown type %u\n" would be better.
~Andrew
On 13.03.2025 16:01, Andrew Cooper wrote:
> On 13/03/2025 1:34 pm, Jan Beulich wrote:
>> Handling possible internal errors by just emitting a (debug-build-only)
>> log message can't be quite enough. Return error codes in those cases,
>> and have the caller propagate those up.
>>
>> Drop a pointless return path, rather than "inventing" an error code for
>> it.
>>
>> While touching the function declarator anyway also constify its first
>> parameter.
>>
>> Fixes: 476bbccc811c ("VT-d: fix MSI source-id of interrupt remapping")
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>
> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>,
Thanks.
> although...
>
>> --- a/xen/drivers/passthrough/vtd/intremap.c
>> +++ b/xen/drivers/passthrough/vtd/intremap.c
>> @@ -436,15 +436,13 @@ void cf_check io_apic_write_remap_rte(
>> __ioapic_write_entry(apic, pin, true, old_rte);
>> }
>>
>> -static void set_msi_source_id(struct pci_dev *pdev, struct iremap_entry *ire)
>> +static int set_msi_source_id(const struct pci_dev *pdev,
>> + struct iremap_entry *ire)
>> {
>> u16 seg;
>> u8 bus, devfn, secbus;
>> int ret;
>>
>> - if ( !pdev || !ire )
>> - return;
>> -
>> seg = pdev->seg;
>> bus = pdev->bus;
>> devfn = pdev->devfn;
>> @@ -485,16 +483,21 @@ static void set_msi_source_id(struct pci
>> PCI_BDF(bus, devfn));
>> }
>> else
>> + {
>> dprintk(XENLOG_WARNING VTDPREFIX,
>> "d%d: no upstream bridge for %pp\n",
>> pdev->domain->domain_id, &pdev->sbdf);
>
> as you're doing cleanup, %pd here? Given DOM_IO for quarantine, I think
> it's more likely now than it used to be.
>
>> + return -ENXIO;
>> + }
>> break;
>>
>> default:
>> dprintk(XENLOG_WARNING VTDPREFIX, "d%d: unknown(%u): %pp\n",
>> pdev->domain->domain_id, pdev->type, &pdev->sbdf);
>
> Here too. Also, the "unknown(%u)" is less than ideal. "%pd: %pp
> unknown type %u\n" would be better.
To be honest this feels like going too far with unrelated cleanup here,
even if it's all in patch context. It would be different if at least I
touched those dprintk() invocations.
Jan
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