Hi all,
Could you please confirm that disabling the other two MSR tests for CS and EIP is also the right thing to do?
Yes I think this is OK. The SYSENTER MSRs are used by the OS and there is nothing which BIOS needs to setup.
Same case is the SYSCALL MSR, GS/FS base and KERNEL GS base and possibly also MSR_TSC_AUX.
#define MSR_STAR 0xc0000081 /* legacy mode SYSCALL target */ #define MSR_LSTAR 0xc0000082 /* long mode SYSCALL target */ #define MSR_CSTAR 0xc0000083 /* compat mode SYSCALL target */ #define MSR_SYSCALL_MASK 0xc0000084 /* EFLAGS mask for syscall */ #define MSR_FS_BASE 0xc0000100 /* 64bit FS base */ #define MSR_GS_BASE 0xc0000101 /* 64bit GS base */ #define MSR_KERNEL_GS_BASE 0xc0000102 /* SwapGS GS shadow */ #define MSR_TSC_AUX 0xc0000103 /* Auxiliary TSC */
Thanks Rudolf