Messages in this thread | | | Subject | Re: [PATCH v7 04/12] x86/cpufeatures: Add TDX Guest CPU feature | From | "Kuppuswamy, Sathyanarayanan" <> | Date | Thu, 23 Sep 2021 07:10:00 -0700 |
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On 9/23/21 3:02 AM, Borislav Petkov wrote: > On Thu, Sep 16, 2021 at 11:35:42AM -0700, Kuppuswamy Sathyanarayanan wrote: >> @@ -495,6 +496,8 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data) >> >> copy_bootdata(__va(real_mode_data)); >> >> + tdx_early_init(); >> + > > | Changes since v4: > | * Moved tdx_early_init() below copy_bootdata() because of > | cmdline and IDT dependencies. > > > What "cmdline and IDT dependencies"? > > Without a comment explaining why that thing must be there in the boot > order, you're adding more to the already fragile house of cards. > > Explain please.
Initially, tdx_early_init() was added between kasan_early_init() and idt_setup_early_handler() in x86_64_start_kernel(). But I found that we have requirement to parse command line params in future changes to tdx_early_init() (not from the patches in this series). Since command line pointer is getting initialized in copy_bootdata(), I want move the tdx_early_init() call below it. Instead of moving the initialization order in future, I thought to move it appropriate place in the initial patch. Regarding IDT dependency, #VE handling will have a dependency on it (so it is better to initialize it before tdx_early_init()).
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-- Sathyanarayanan Kuppuswamy Linux Kernel Developer
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