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* [build] Mark known reviewed files as permitted for UEFI Secure BootMichael Brown2026-01-141-0/+1
| | | | | | | | | Some past security reviews carried out for UEFI Secure Boot signing submissions have covered specific drivers or functional areas of iPXE. Mark all of the files comprising these areas as permitted for UEFI Secure Boot. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [pci] Map all MSI-X interrupts to a dummy target address by defaultMichael Brown2025-10-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | Interrupts as such are not used in iPXE, which operates in polling mode. However, some network cards (such as the Intel 40GbE and 100GbE NICs) will defer writing out completions until the point of asserting an MSI-X interrupt. From the point of view of the PCI device, asserting an MSI-X interrupt is just a 32-bit DMA write of an opaque value to an opaque target address. The PCI device has no know to know whether or not the target address corresponds to a real APIC. We can therefore trick the PCI device into believing that it is asserting an MSI-X interrupt, by configuring it to write an opaque 32-bit value to a dummy target address in host memory. This is sufficient to trigger the associated write of the completions to host memory. Allocate a dummy target address when enabling MSI-X on a PCI device, and map all interrupts to this target address by default. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [pci] Add support for PCI MSI-X interruptsMichael Brown2019-04-241-0/+77
The Intel 40 Gigabit Ethernet virtual functions support only MSI-X interrupts, and will write back completed interrupt descriptors only when the device attempts to raise an interrupt (or when a complete cacheline of receive descriptors has been completed). We cannot actually use MSI-X interrupts within iPXE, since we never have ownership of the APIC. However, an MSI-X interrupt is fundamentally just a DMA write of a single dword to an arbitrary address. We can therefore configure the device to "raise" an interrupt by writing a meaningless value to an otherwise unused memory location: this is sufficient to trigger the receive descriptor writeback logic. Signed-off-by: Michael Brown <mcb30@ipxe.org>