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954b4b752a
The MSI message address in the RC address space can be 64 bit. The
R-Car PCIe RC supports such a 64bit MSI message address as well.
The code currently uses virt_to_phys(__get_free_pages()) to obtain
a reserved page for the MSI message address, and the return value
of which can be a 64 bit physical address on 64 bit system.
However, the driver only programs PCIEMSIALR register with the bottom
32 bits of the virt_to_phys(__get_free_pages()) return value and does
not program the top 32 bits into PCIEMSIAUR, but rather programs the
PCIEMSIAUR register with 0x0. This worked fine on older 32 bit R-Car
SoCs, however may fail on new 64 bit R-Car SoCs.
Since from a PCIe controller perspective, an inbound MSI is a memory
write to a special address (in case of this controller, defined by
the value in PCIEMSIAUR:PCIEMSIALR), which triggers an interrupt, but
never hits the DRAM _and_ because allocation of an MSI by a PCIe card
driver obtains the MSI message address by reading PCIEMSIAUR:PCIEMSIALR
in rcar_msi_setup_irqs(), incorrectly programmed PCIEMSIAUR cannot
cause memory corruption or other issues.
There is however the possibility that if virt_to_phys(__get_free_pages())
returned address above the 32bit boundary _and_ PCIEMSIAUR was programmed
to 0x0 _and_ if the system had physical RAM at the address matching the
value of PCIEMSIALR, a PCIe card driver could allocate a buffer with a
physical address matching the value of PCIEMSIALR and a remote write to
such a buffer by a PCIe card would trigger a spurious MSI.
Fixes:
|
||
|---|---|---|
| .. | ||
| dwc | ||
| Kconfig | ||
| Makefile | ||
| pci-aardvark.c | ||
| pci-ftpci100.c | ||
| pci-host-common.c | ||
| pci-host-generic.c | ||
| pci-hyperv.c | ||
| pci-mvebu.c | ||
| pci-rcar-gen2.c | ||
| pci-tegra.c | ||
| pci-thunder-ecam.c | ||
| pci-thunder-pem.c | ||
| pci-v3-semi.c | ||
| pci-versatile.c | ||
| pci-xgene-msi.c | ||
| pci-xgene.c | ||
| pcie-altera-msi.c | ||
| pcie-altera.c | ||
| pcie-cadence-ep.c | ||
| pcie-cadence-host.c | ||
| pcie-cadence.c | ||
| pcie-cadence.h | ||
| pcie-iproc-bcma.c | ||
| pcie-iproc-msi.c | ||
| pcie-iproc-platform.c | ||
| pcie-iproc.c | ||
| pcie-iproc.h | ||
| pcie-mediatek.c | ||
| pcie-mobiveil.c | ||
| pcie-rcar.c | ||
| pcie-rockchip-ep.c | ||
| pcie-rockchip-host.c | ||
| pcie-rockchip.c | ||
| pcie-rockchip.h | ||
| pcie-tango.c | ||
| pcie-xilinx-nwl.c | ||
| pcie-xilinx.c | ||
| vmd.c | ||