403bb8185e
1 Commits
Author | SHA1 | Message | Date | |
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Laszlo Ersek
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09a274d82f |
tests: introduce "uefi-test-tools" with the BiosTablesTest UEFI app
The "bios-tables-test" program in QEMU's test suite locates the RSD PTR ACPI table in guest RAM, and (chasing pointers to other ACPI tables) performs various sanity checks on the QEMU-generated and firmware-installed tables. Currently this set of test cases doesn't work with UEFI guests. The ACPI spec defines distinct methods for OSPM to locate the RSD PTR on traditional BIOS vs. UEFI platforms, and the UEFI method is more difficult to implement from the hypervisor side with just raw guest memory access. Add a UEFI application (to be booted in the UEFI guest) that populates a small, MB-aligned structure in guest RAM. The structure begins with a signature GUID. The hypervisor should loop over all MB-aligned pages in guest RAM until one matches the signature GUID at offset 0, at which point the hypervisor can fetch the RSDP address field(s) from the structure. QEMU's test logic currently spins on a pre-determined guest address, until that address assumes a magic value. The method described in this patch is conceptually the same ("busy loop until match is found"), except there is no hard-coded address. This plays a lot more nicely with UEFI guest firmware (we'll be able to use the normal page allocation UEFI service). Given the size of EFI_GUID (16 bytes -- 128 bits), mismatches should be astronomically unlikely. In addition, given the typical guest RAM size for such tests (128 MB), there are 128 locations to check in one iteration of the "outer" loop, which shouldn't introduce an intolerable delay after the guest stores the RSDP address(es), and then the GUID. The GUID that the hypervisor should search for is AB87A6B1-2034-BDA0-71BD-375007757785 Expressed as a byte array: { 0xb1, 0xa6, 0x87, 0xab, 0x34, 0x20, 0xa0, 0xbd, 0x71, 0xbd, 0x37, 0x50, 0x07, 0x75, 0x77, 0x85 } Note that in the patch, we define "gBiosTablesTestGuid" with all bits inverted. This is a simple method to prevent the UEFI binary, which incorporates "gBiosTablesTestGuid", from matching the actual GUID in guest RAM. The UEFI application is written against the edk2 framework, which was introduced earlier as a git submodule. The next patch will provide build scripts for maintainers. The source code follows the edk2 coding style, and is licensed under the 2-clause BSDL (in case someone would like to include UefiTestToolsPkg content in a different edk2 platform). The "UefiTestToolsPkg.dsc" platform description file resolves the used edk2 library classes to instances (= library implementations) such that the UEFI binaries inherit no platform dependencies. They are expected to run on any system that conforms to the UEFI-2.3.1 spec (which was released in 2012). The arch-specific build options are carried over from edk2's ArmVirtPkg and OvmfPkg platforms. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Philippe Mathieu-Daudé <philmd@redhat.com> Cc: Shannon Zhao <shannon.zhaosl@gmail.com> Signed-off-by: Laszlo Ersek <lersek@redhat.com> Message-Id: <20190204160325.4914-4-lersek@redhat.com> Reviewed-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> |