Messages in this thread | ![/](/images/icornerl.gif) | | Date | Thu, 25 Jan 2024 05:07:47 -0800 | From | "H. Peter Anvin" <> | Subject | Re: [PATCHv3, RESEND] x86/trampoline: Bypass co mpat mode in trampoline start64() if not needed |
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On January 25, 2024 1:57:18 AM PST, Andi Kleen <ak@linux.intel.com> wrote: >> + /* Paging mode is correct proceed in 64-bit mode */ >> + >> + LOCK_AND_LOAD_REALMODE_ESP lock_rip=1 >> + >> + movw $__KERNEL_DS, %dx >> + movl %edx, %ss >> + addl $pa_real_mode_base, %esp >> + movl %edx, %ds >> + movl %edx, %es >> + movl %edx, %fs >> + movl %edx, %gs >> + >> + movl $pa_trampoline_pgd, %eax >> + movq %rax, %cr3 >> + >> + jmpq *tr_start(%rip) > >Still think we should add a far jump here so that we run on a defined >code segment. It probably doesn't matter since there are likely no >IRETs before reloading anyways, but it seems cleaner. > >-Andi >
Agreed.
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