| Message ID | 1632474612-9940-1-git-send-email-igor.druzhinin@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] pci: fix handling of PCI bridges with subordinate bus number 0xff | expand |
On 24.09.2021 11:10, Igor Druzhinin wrote: > Bus number 0xff is valid according to the PCI spec. Using u8 typed sub_bus > and assigning 0xff to it will result in the following loop getting stuck. > > for ( ; sec_bus <= sub_bus; sec_bus++ ) {...} > > Just change its type to unsigned int similarly to what is already done in > dmar_scope_add_buses(). > > Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Hi, > On 24 Sep 2021, at 10:10, Igor Druzhinin <igor.druzhinin@citrix.com> wrote: > > Bus number 0xff is valid according to the PCI spec. Using u8 typed sub_bus > and assigning 0xff to it will result in the following loop getting stuck. > > for ( ; sec_bus <= sub_bus; sec_bus++ ) {...} > > Just change its type to unsigned int similarly to what is already done in > dmar_scope_add_buses(). > > Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com> Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com> Cheers Bertrand > --- > v2: > - fix free_pdev() as well > - style fixes > --- > xen/drivers/passthrough/pci.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c > index fc4fa2e..d65cda8 100644 > --- a/xen/drivers/passthrough/pci.c > +++ b/xen/drivers/passthrough/pci.c > @@ -363,8 +363,7 @@ static struct pci_dev *alloc_pdev(struct pci_seg *pseg, u8 bus, u8 devfn) > /* update bus2bridge */ > switch ( pdev->type = pdev_type(pseg->nr, bus, devfn) ) > { > - u16 cap; > - u8 sec_bus, sub_bus; > + unsigned int cap, sec_bus, sub_bus; > > case DEV_TYPE_PCIe2PCI_BRIDGE: > case DEV_TYPE_LEGACY_PCI_BRIDGE: > @@ -431,7 +430,7 @@ static void free_pdev(struct pci_seg *pseg, struct pci_dev *pdev) > /* update bus2bridge */ > switch ( pdev->type ) > { > - uint8_t sec_bus, sub_bus; > + unsigned int sec_bus, sub_bus; > > case DEV_TYPE_PCIe2PCI_BRIDGE: > case DEV_TYPE_LEGACY_PCI_BRIDGE: > -- > 2.7.4 > >
diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c index fc4fa2e..d65cda8 100644 --- a/xen/drivers/passthrough/pci.c +++ b/xen/drivers/passthrough/pci.c @@ -363,8 +363,7 @@ static struct pci_dev *alloc_pdev(struct pci_seg *pseg, u8 bus, u8 devfn) /* update bus2bridge */ switch ( pdev->type = pdev_type(pseg->nr, bus, devfn) ) { - u16 cap; - u8 sec_bus, sub_bus; + unsigned int cap, sec_bus, sub_bus; case DEV_TYPE_PCIe2PCI_BRIDGE: case DEV_TYPE_LEGACY_PCI_BRIDGE: @@ -431,7 +430,7 @@ static void free_pdev(struct pci_seg *pseg, struct pci_dev *pdev) /* update bus2bridge */ switch ( pdev->type ) { - uint8_t sec_bus, sub_bus; + unsigned int sec_bus, sub_bus; case DEV_TYPE_PCIe2PCI_BRIDGE: case DEV_TYPE_LEGACY_PCI_BRIDGE:
Bus number 0xff is valid according to the PCI spec. Using u8 typed sub_bus and assigning 0xff to it will result in the following loop getting stuck. for ( ; sec_bus <= sub_bus; sec_bus++ ) {...} Just change its type to unsigned int similarly to what is already done in dmar_scope_add_buses(). Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com> --- v2: - fix free_pdev() as well - style fixes --- xen/drivers/passthrough/pci.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)