diff options
| -rw-r--r-- | arch/x86/Kconfig | 85 | ||||
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 4 |
2 files changed, 58 insertions, 31 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 98bd4935280c..e72cb7779038 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -458,20 +458,27 @@ config SMP If you don't know what to do here, say N. config X86_X2APIC - bool "Support x2apic" + bool "x2APIC interrupt controller architecture support" depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) + default y help - This enables x2apic support on CPUs that have this feature. + x2APIC is an interrupt controller architecture, a component of which + (the local APIC) is present in the CPU. It allows faster access to + the local APIC and supports a larger number of CPUs in the system + than the predecessors. - This allows 32-bit apic IDs (so it can support very large systems), - and accesses the local apic via MSRs not via mmio. + x2APIC was introduced in Intel CPUs around 2008 and in AMD EPYC CPUs + in 2019, but it can be disabled by the BIOS. It is also frequently + emulated in virtual machines, even when the host CPU does not support + it. Support in the CPU can be checked by executing + cat /proc/cpuinfo | grep x2apic - Some Intel systems circa 2022 and later are locked into x2APIC mode - and can not fall back to the legacy APIC modes if SGX or TDX are - enabled in the BIOS. They will boot with very reduced functionality - without enabling this option. + If this configuration option is disabled, the kernel will not boot on + some platforms that have x2APIC enabled. - If you don't know what to do here, say N. + Say N if you know that your platform does not have x2APIC. + + Otherwise, say Y. config X86_POSTED_MSI bool "Enable MSI and MSI-x delivery by posted interrupts" @@ -535,16 +542,20 @@ config X86_EXTENDED_PLATFORM CONFIG_64BIT. 32-bit platforms (CONFIG_64BIT=n): - Goldfish (Android emulator) - AMD Elan + Goldfish (mostly Android emulator) + Intel CE media processor (CE4100) SoC + Intel MID (Mobile Internet Device) + Intel Quark RDC R-321x SoC - SGI 320/540 (Visual Workstation) + STA2X11-based (e.g. Northville) 64-bit platforms (CONFIG_64BIT=y): Numascale NumaChip ScaleMP vSMP SGI Ultraviolet Merrifield/Moorefield MID devices + Goldfish (mostly Android emulator) + Intel MID (Mobile Internet Device) If you have one of these systems, or if you want to build a generic distribution kernel, say Y here - otherwise say N. @@ -658,6 +669,17 @@ config X86_INTEL_QUARK Say Y here if you have a Quark based system such as the Arduino compatible Intel Galileo. +config X86_RDC321X + bool "RDC R-321x SoC" + depends on X86_32 + depends on X86_EXTENDED_PLATFORM + select M486 + select X86_REBOOTFIXUPS + help + This option is needed for RDC R-321x system-on-chip, also known + as R-8610-(G). + If you don't have one of these chips, you should say N here. + config X86_INTEL_LPSS bool "Intel Low Power Subsystem Support" depends on X86 && ACPI && PCI @@ -711,17 +733,6 @@ config IOSF_MBI_DEBUG If you don't require the option or are in doubt, say N. -config X86_RDC321X - bool "RDC R-321x SoC" - depends on X86_32 - depends on X86_EXTENDED_PLATFORM - select M486 - select X86_REBOOTFIXUPS - help - This option is needed for RDC R-321x system-on-chip, also known - as R-8610-(G). - If you don't have one of these chips, you should say N here. - config X86_SUPPORTS_MEMORY_FAILURE def_bool y # MCE code calls memory_failure(): @@ -1556,7 +1567,6 @@ config ARCH_FLATMEM_ENABLE config ARCH_SPARSEMEM_ENABLE def_bool y - depends on X86_64 || NUMA || X86_32 select SPARSEMEM_STATIC if X86_32 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 @@ -2203,7 +2213,7 @@ config HOTPLUG_CPU config COMPAT_VDSO def_bool n - prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" + prompt "Workaround for glibc 2.3.2 / 2.3.3 (released in year 2003/2004)" depends on COMPAT_32 help Certain buggy versions of glibc will crash if they are @@ -2892,6 +2902,19 @@ config PCI_MMCONFIG default y depends on PCI && (ACPI || JAILHOUSE_GUEST) depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) + help + Add support for accessing the PCI configuration space as a memory + mapped area. It is the recommended method if the system supports + this (it must have PCI Express and ACPI for it to be available). + + In the unlikely case that enabling this configuration option causes + problems, the mechanism can be switched off with the 'pci=nommconf' + command line parameter. + + Say N only if you are sure that your platform does not support this + access method or you have problems caused by it. + + Say Y otherwise. config PCI_OLPC def_bool y @@ -2906,13 +2929,21 @@ config MMCONF_FAM10H depends on X86_64 && PCI_MMCONFIG && ACPI config PCI_CNB20LE_QUIRK - bool "Read CNB20LE Host Bridge Windows" if EXPERT - depends on PCI + bool "Read PCI host bridge windows from the CNB20LE chipset" if EXPERT + depends on X86_32 && PCI help Read the PCI windows out of the CNB20LE host bridge. This allows PCI hotplug to work on systems with the CNB20LE chipset which do not have ACPI. + The ServerWorks (later Broadcom) CNB20LE was a chipset designed + most probably only for Pentium III. + + To find out if you have such a chipset, search for a PCI device with + 1166:0009 PCI IDs, for example by executing + lspci -nn | grep '1166:0009' + The code is inactive if there is none. + There's no public spec for this chipset, and this functionality is known to be incomplete. diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index 804b66a7686a..29ea8fb16273 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -435,12 +435,8 @@ static inline void call_depth_return_thunk(void) {} * Inline asm uses the %V modifier which is only in newer GCC * which is ensured when CONFIG_MITIGATION_RETPOLINE is defined. */ -#ifdef CONFIG_MITIGATION_RETPOLINE #define CALL_NOSPEC __CS_PREFIX("%V[thunk_target]") \ "call __x86_indirect_thunk_%V[thunk_target]\n" -#else -#define CALL_NOSPEC "call *%[thunk_target]\n" -#endif # define THUNK_TARGET(addr) [thunk_target] "r" (addr) |