[PATCH v2 1/7] PCI: aardvark: fix logic in PCI configuration read/write functions
From: helgaas@kernel.org (Bjorn Helgaas)
Date: 2017-10-05 17:23:33
Also in:
linux-pci, stable
On Thu, Sep 28, 2017 at 02:58:32PM +0200, Thomas Petazzoni wrote:
quoted hunk ↗ jump to hunk
From: Victor Gu <redacted> The PCI configuration space read/write functions were special casing the situation where PCI_SLOT(devfn) != 0, and returned PCIBIOS_DEVICE_NOT_FOUND in this case. However, will this is what is intended for the root bus, it is not intended for the child busses, as it prevents discovering devices with PCI_SLOT(x) != 0. Therefore, we return PCIBIOS_DEVICE_NOT_FOUND only if we're on the root bus. Fixes: 8c39d710363c1 ("PCI: aardvark: Add Aardvark PCI host controller driver") Cc: <redacted> Signed-off-by: Victor Gu <redacted> Reviewed-by: Wilson Ding <redacted> Reviewed-by: Nadav Haklai <redacted> [Thomas: tweak commit log.] Signed-off-by: Thomas Petazzoni <redacted> --- drivers/pci/host/pci-aardvark.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)diff --git a/drivers/pci/host/pci-aardvark.c b/drivers/pci/host/pci-aardvark.c index 89f4e3d072d7..da2881ba7737 100644 --- a/drivers/pci/host/pci-aardvark.c +++ b/drivers/pci/host/pci-aardvark.c@@ -440,7 +440,7 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, u32 reg; int ret; - if (PCI_SLOT(devfn) != 0) { + if ((bus->number == pcie->root_bus_nr) && (PCI_SLOT(devfn) != 0)) {
I'm fine with this, but please take a look at these: 8e7ca8ca5fd8 PCI: xilinx: Relax device number checking to allow SR-IOV e18934b5e9c7 PCI: designware: Relax device number checking to allow SR-IOV d99e30b7936a PCI: altera: Relax device number checking to allow SR-IOV and make sure that reasoning doesn't apply here, too. http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=8e7ca8ca5fd8 http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=e18934b5e9c7 http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d99e30b7936a
quoted hunk ↗ jump to hunk
*val = 0xffffffff; return PCIBIOS_DEVICE_NOT_FOUND; }@@ -494,7 +494,7 @@ static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn, int offset; int ret; - if (PCI_SLOT(devfn) != 0) + if ((bus->number == pcie->root_bus_nr) && (PCI_SLOT(devfn) != 0)) return PCIBIOS_DEVICE_NOT_FOUND; if (where % size)-- 2.13.5 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel at lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel