Messages in this thread | | | Date | Thu, 3 Mar 2016 17:18:34 -0800 | Subject | Re: [RFC PATCH] x86: Make sure verify_cpu has a good stack | From | Yinghai Lu <> |
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On Thu, Mar 3, 2016 at 4:28 AM, Borislav Petkov <bp@alien8.de> wrote: > > 04633df0c43d ("x86/cpu: Call verify_cpu() after having entered long mode too") > added the call to verify_cpu() for sanitizing CPU configuration. > > The latter uses the stack minimally and it can happen that we land in > startup_64() directly from a 64-bit bootloader. Then we want to use our > own, known good stack. > > Do that. > > APs don't need this as the trampoline sets up a stack for them.
Even more than that. For AP verify_cpu already get called in trampoline.
arch/x86/realmode/rm/trampoline_64.S::trampoline_start().
So you remove verify_cpu calling in secondary_startup_64.
Yinghai
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