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authorLinus Torvalds <torvalds@linux-foundation.org>2022-05-24 02:51:12 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2022-05-24 02:51:12 +0200
commit3a755ebcc2557e22b895b8976257f682c653db1d (patch)
tree7aeda9181996705ad1c82690b85ac53fe3b41716 /kernel/cpu.c
parentMerge tag 'ras_core_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kern... (diff)
parentx86/tdx: Fix RETs in TDX asm (diff)
downloadlinux-3a755ebcc2557e22b895b8976257f682c653db1d.tar.xz
linux-3a755ebcc2557e22b895b8976257f682c653db1d.zip
Merge tag 'x86_tdx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull Intel TDX support from Borislav Petkov: "Intel Trust Domain Extensions (TDX) support. This is the Intel version of a confidential computing solution called Trust Domain Extensions (TDX). This series adds support to run the kernel as part of a TDX guest. It provides similar guest protections to AMD's SEV-SNP like guest memory and register state encryption, memory integrity protection and a lot more. Design-wise, it differs from AMD's solution considerably: it uses a software module which runs in a special CPU mode called (Secure Arbitration Mode) SEAM. As the name suggests, this module serves as sort of an arbiter which the confidential guest calls for services it needs during its lifetime. Just like AMD's SNP set, this series reworks and streamlines certain parts of x86 arch code so that this feature can be properly accomodated" * tag 'x86_tdx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) x86/tdx: Fix RETs in TDX asm x86/tdx: Annotate a noreturn function x86/mm: Fix spacing within memory encryption features message x86/kaslr: Fix build warning in KASLR code in boot stub Documentation/x86: Document TDX kernel architecture ACPICA: Avoid cache flush inside virtual machines x86/tdx/ioapic: Add shared bit for IOAPIC base address x86/mm: Make DMA memory shared for TD guest x86/mm/cpa: Add support for TDX shared memory x86/tdx: Make pages shared in ioremap() x86/topology: Disable CPU online/offline control for TDX guests x86/boot: Avoid #VE during boot for TDX platforms x86/boot: Set CR0.NE early and keep it set during the boot x86/acpi/x86/boot: Add multiprocessor wake-up support x86/boot: Add a trampoline for booting APs via firmware handoff x86/tdx: Wire up KVM hypercalls x86/tdx: Port I/O: Add early boot support x86/tdx: Port I/O: Add runtime hypercalls x86/boot: Port I/O: Add decompression-time support for TDX x86/boot: Port I/O: Allow to hook up alternative helpers ...
Diffstat (limited to 'kernel/cpu.c')
-rw-r--r--kernel/cpu.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 02a77ac08399..bbad5e375d3b 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -35,6 +35,7 @@
#include <linux/percpu-rwsem.h>
#include <linux/cpuset.h>
#include <linux/random.h>
+#include <linux/cc_platform.h>
#include <trace/events/power.h>
#define CREATE_TRACE_POINTS
@@ -1190,6 +1191,12 @@ out:
static int cpu_down_maps_locked(unsigned int cpu, enum cpuhp_state target)
{
+ /*
+ * If the platform does not support hotplug, report it explicitly to
+ * differentiate it from a transient offlining failure.
+ */
+ if (cc_platform_has(CC_ATTR_HOTPLUG_DISABLED))
+ return -EOPNOTSUPP;
if (cpu_hotplug_disabled)
return -EBUSY;
return _cpu_down(cpu, 0, target);