On Thu, Nov 25, 2021 at 01:45:54PM +0100, Pali Rohár wrote: > Function mvebu_pcie_hw_rd_conf() does not handle invalid size. So correctly > set read value to all-ones and return appropriate error return value > PCIBIOS_BAD_REGISTER_NUMBER like in mvebu_pcie_hw_wr_conf() function. > > Signed-off-by: Pali Rohár <pali@xxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx Is there a bug that this fixes? If not, I would drop the stable tag (as I see Lorenzo already did, thanks!). > --- > drivers/pci/controller/pci-mvebu.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c > index 08274132cdfb..19c6ee298442 100644 > --- a/drivers/pci/controller/pci-mvebu.c > +++ b/drivers/pci/controller/pci-mvebu.c > @@ -261,6 +261,9 @@ static int mvebu_pcie_hw_rd_conf(struct mvebu_pcie_port *port, > case 4: > *val = readl_relaxed(conf_data); > break; > + default: > + *val = 0xffffffff; > + return PCIBIOS_BAD_REGISTER_NUMBER; Might be the right thing to do, but there are many config accessors that do not set *val to ~0 before returning PCIBIOS_BAD_REGISTER_NUMBER: pci_bus_read_config_byte (and word, dword) # PCI_OP_READ(), *val unchanged pci_generic_config_read # *val = 32-bit value pci_user_read_config_byte (...) # PCI_USER_READ_CONFIG(), *val unchanged sh7786_pcie_read # *val unchanged dw_pcie_read # *val = 0 mobiveil_pcie_read # *val = 0 faraday_raw_pci_read_config # *val = 32-bit value ixp4xx_pci_read_config # *val unchanged orion5x_pci_hw_rd_conf # *val = 32-bit value orion_pcie_rd_conf # *val = 32-bit value bonito64_pcibios_read # *val = 32-bit value loongson_pcibios_read # *val = 32-bit value msc_pcibios_read # *val = 32-bit value ar724x_pci_read # *val unchanged bcm1480_pcibios_read # *val = 32-bit value _altera_pcie_cfg_read # *val = 32-bit value rockchip_pcie_rd_own_conf # *val = 0 rockchip_pcie_rd_other_conf # *val = 0 pci_bridge_emul_conf_read # may depend on op? There are more, but I got tired of looking. I actually didn't see any that set *val to ~0. I think the check in PCI_OP_READ() means that most accessors will never see an invalid "size". > } > > return PCIBIOS_SUCCESSFUL; > -- > 2.20.1 >
