The following commit has been merged into the x86/build branch of tip: Commit-ID: 88a2b4edda3d0709727be53f4423b0b832d91de3 Gitweb: https://git.kernel.org/tip/88a2b4edda3d0709727be53f4423b0b832d91de3 Author: Arnd Bergmann <arnd@xxxxxxxx> AuthorDate: Mon, 04 Dec 2023 09:47:02 +01:00 Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx> CommitterDate: Tue, 19 Dec 2023 13:03:06 +01:00 x86/Kconfig: Rework CONFIG_X86_PAE dependency While looking at a Xen Kconfig dependency issue, I tried to understand the exact dependencies for CONFIG_X86_PAE, which is selected by CONFIG_HIGHMEM64G but can also be enabled manually. Apparently the dependencies for CONFIG_HIGHMEM64G are strictly about CPUs that do support PAE, but the actual feature can be incorrectly enabled on older CPUs as well. The CONFIG_X86_CMPXCHG64 dependencies on the other hand include X86_PAE because cmpxchg8b is requried for PAE to work. Rework this for readability and correctness, using a positive list of CPUs that support PAE in a new X86_HAVE_PAE symbol that can serve as a dependency for both X86_PAE and HIGHMEM64G as well as simplify the X86_CMPXCHG64 dependency list. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Link: https://lore.kernel.org/r/20231204084722.3789473-2-arnd@xxxxxxxxxx --- arch/x86/Kconfig | 4 ++-- arch/x86/Kconfig.cpu | 6 +++++- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 3762f41..4692380 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1415,7 +1415,7 @@ config HIGHMEM4G config HIGHMEM64G bool "64GB" - depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !MWINCHIP3D && !MK6 + depends on X86_HAVE_PAE select X86_PAE help Select this if you have a 32-bit processor and more than 4 @@ -1472,7 +1472,7 @@ config HIGHMEM config X86_PAE bool "PAE (Physical Address Extension) Support" - depends on X86_32 && !HIGHMEM4G + depends on X86_32 && X86_HAVE_PAE select PHYS_ADDR_T_64BIT select SWIOTLB help diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu index 00468ad..b9224cf 100644 --- a/arch/x86/Kconfig.cpu +++ b/arch/x86/Kconfig.cpu @@ -362,9 +362,13 @@ config X86_TSC def_bool y depends on (MWINCHIP3D || MCRUSOE || MEFFICEON || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MVIAC3_2 || MVIAC7 || MGEODEGX1 || MGEODE_LX || MCORE2 || MATOM) || X86_64 +config X86_HAVE_PAE + def_bool y + depends on MCRUSOE || MEFFICEON || MCYRIXIII || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC7 || MCORE2 || MATOM || X86_64 + config X86_CMPXCHG64 def_bool y - depends on X86_PAE || X86_64 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586TSC || M586MMX || MATOM || MGEODE_LX || MGEODEGX1 || MK6 || MK7 || MK8 + depends on X86_HAVE_PAE || M586TSC || M586MMX || MK6 || MK7 # this should be set for all -march=.. options where the compiler # generates cmov.