Hi Minitri 1. You are right that, this will happen if we do not use 4K alignment for PE/COFF image. (.code and .data segs are merged in x86) In current implementation, if a platform defines EFI_PROPERTIES_TABLE/EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA, and use 4K alignment link option. Data seg will be returned as EfiRuntimeServicesData.
2. I am not sure what "moved" means here. It is true that OS will use non-1:1 mapping virtual address for EfiRuntimeServicesData, which means Virtual address is changed. But the physical address is still same. PiSmmCore is inside of SMM, so it can still access same physical address, by using 1:1 mapping paging in SMM. Thank you Yao Jiewen -----Original Message----- From: edk2-devel [mailto:[email protected]] On Behalf Of iMac Pro Sent: Thursday, October 15, 2015 4:59 PM To: [email protected] Subject: [edk2] SMM core problems Hi, Found that problems in PiSmmIpl.c/PiSmmCore.c: 1. SMM_CORE_PRIVATE_DATA *gSmmCorePrivate is pointer to EfiRuntimeServicesCode (.code and .data segs are merged in x86) memory that can be declared as ReadOnly by OS. But SmmCommunicationCommunicate write to it. GPE in OS !!! 2. EfiRuntimeServicesData memory can be moved by OS loader physically. ("preserved by the loader" in spec - not means in the same place). So this is not best place to store SMM_CORE_PRIVATE_DATA also, because PiSmmCore.c.does not know that boot loader moved it. Best regards, Dimitri _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
