Cc: Anthony Perard <anthony.per...@citrix.com> Cc: Ard Biesheuvel <ard.biesheu...@linaro.org> Cc: Jordan Justen <jordan.l.jus...@intel.com> Cc: Julien Grall <julien.gr...@linaro.org> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <ler...@redhat.com> --- OvmfPkg/README | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/OvmfPkg/README b/OvmfPkg/README index 00fb71848200..cdd8dbea7f18 100644 --- a/OvmfPkg/README +++ b/OvmfPkg/README @@ -68,13 +68,21 @@ https://github.com/tianocore/tianocore.github.io/wiki/How%20to%20build%20OVMF * Run qemu with: -pflash path/to/OVMF.fd * Note that this option is required for running SecureBoot-enabled builds (-D SECURE_BOOT_ENABLE). + * When a commitment to this option (i.e., -pflash) can be made, it is + recommended to build OVMF with -D MEM_VARSTORE_EMU_ENABLE=FALSE. Said + build setting enables UEFI memory map defragmentation across boots of the + virtual machine. - Option 2: Use QEMU -bios parameter * Note that UEFI variables will be partially emulated, and non-volatile variables may lose their contents after a reboot + * The build option -D MEM_VARSTORE_EMU_ENABLE=FALSE is incompatible with + the QEMU -bios option. * Run qemu with: -bios path/to/OVMF.fd - Option 3: Use QEMU -L parameter * Note that UEFI variables will be partially emulated, and non-volatile variables may lose their contents after a reboot + * The build option -D MEM_VARSTORE_EMU_ENABLE=FALSE is incompatible with + the QEMU -L option. * Either copy, rename or symlink OVMF.fd => bios.bin * Use the QEMU -L parameter to specify the directory where the bios.bin file is located. @@ -139,6 +147,8 @@ during boot (even in RELEASE builds). Both the naming of the flag (SMM_REQUIRE, instead of SMM_ENABLE), and this behavior are consistent with the goal described above: this is supposed to be a security feature, and fallbacks are not allowed. Similarly, a pflash-backed variable store is a requirement. +(Accordingly, SMM_REQUIRE automatically enables all benefits of +MEM_VARSTORE_EMU_ENABLE=FALSE). QEMU should be started with the options listed below (in addition to any other guest-specific flags). The command line should be gradually composed from the -- 2.14.1.3.gb7cf6e02401b _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
