diff --git a/SUPPORT.md b/SUPPORT.md index cd786ac0c1..c45390a245 100644 --- a/SUPPORT.md +++ b/SUPPORT.md @@ -82,14 +82,7 @@ No hardware requirements Status, x86_64: Supported Status, x86_32, shim: Supported - Status, x86_32, without shim: Supported, with caveats - -Due to architectural limitations, -32-bit PV guests must be assumed to be able to read arbitrary host memory -using speculative execution attacks. -Advisories will continue to be issued -for new vulnerabilities related to un-shimmed 32-bit PV guests -enabling denial-of-service attacks or privilege escalation attacks. + Status, x86_32, without shim: Supported, not security supported ### x86/HVM diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig index a636a4bb1e..8af5d6be80 100644 --- a/xen/arch/x86/Kconfig +++ b/xen/arch/x86/Kconfig @@ -56,7 +56,7 @@ config PV config PV32 bool "Support for 32bit PV guests" depends on PV - default y + default PV_SHIM ---help--- The 32bit PV ABI uses Ring1, an area of the x86 architecture which was deprecated and mostly removed in the AMD64 spec. As a result, @@ -67,7 +67,10 @@ config PV32 reduction, or performance reasons. Backwards compatibility can be provided via the PV Shim mechanism. - If unsure, say Y. + Note that outside of PV Shim, 32-bit PV guests are not security + supported anymore. + + If unsure, use the default setting. config PV_LINEAR_PT bool "Support for PV linear pagetables"