On Thu, Feb 20, 2025 at 1:47 PM Dave Hansen <dave.hansen@xxxxxxxxx> wrote: > > On 2/20/25 13:16, Vishal Annapurve wrote: > > Since enabling CONFIG_PARAVIRT_XXL is too bloated for TDX guest > > like platforms, move HLT and SAFE_HLT paravirt calls under > > CONFIG_PARAVIRT. > > I guess it's just one patch, but doesn't this expose CONFIG_PARAVIRT=y > users to what _was_ specific to CONFIG_PARAVIRT_XXL=y? According to the > changelog, TDX users shouldn't have to use use PARAVIRT_XXL, so > PARAVIRT=y and PARAVIRT_XXL=n must be an *IMPORTANT* configuration for > TDX users. > > Before this patch, those users would have no way to hit the > unsafe-for-TDX pv_native_safe_halt(). After this patch, they will hit it. Before this patch, those users had access to arch_safe_halt() -> native_safe_halt() path. With this patch, such users can execute arch_safe_halt -> pv_native_safe_halt() -> native_safe_halt(), so this patch doesn't cause any additional regression. > > So, there are two possibilities: > > 1. This patch breaks bisection for an important TDX configuration > 2. This patch's conjecture that PARAVIRT_XXL=n is important for TDX > is wrong and it is not necessary in the first place. > > What am I missing?
