Source: edk2 Severity: wishlist Dear Maintainer(s),
Current OVMF binaries for use with qemu (at least on x86_64) are built so that the debug function DebugClearMemory() runs and overwrites any pages being freed with BS->FreePages() with a fixed 0xAF pattern. Other than being most likely bad for performance, this recently also caused some headaches in shim when pages that were used to load images, and thus marked as non-writable and executable, were freed, which made OVMF attempt to overwrite them, which causes a crash due to non- writable attribute being set. For more details, see: https://github.com/rhboot/shim/pull/750 As far as I can tell, this is caused by the 0x08 bit being set in gEfiMdePkgTokenSpaceGuid.PcdDebugPropertyMask in the OvmfPKgX64.dsc by default. Should the packages provide alternative debug binaries where these flags are enabled? Running this code is certainly useful for testing purposes, but I'm not sure for production usage. Separate debug-enabled binaries have been requested already in other bug reports, so maybe this flag could be enabled there, and removed from default builds? Thanks!
