Lai Jiangshan a217a6593c KVM/VMX: Invoke NMI non-IST entry instead of IST entry ... In VMX, the host NMI handler needs to be invoked after NMI VM-Exit. Before commit 1a5488ef0d ("KVM: VMX: Invoke NMI handler via indirect call instead of INTn"), this was done by INTn ("int $2"). But INTn microcode is relatively expensive, so the commit reworked NMI VM-Exit handling to invoke the kernel handler by function call. But this missed a detail. The NMI entry point for direct invocation is fetched from the IDT table and called on the kernel stack. But on 64-bit the NMI entry installed in the IDT expects to be invoked on the IST stack. It relies on the "NMI executing" variable on the IST stack to work correctly, which is at a fixed position in the IST stack. When the entry point is unexpectedly called on the kernel stack, the RSP-addressed "NMI executing" variable is obviously also on the kernel stack and is "uninitialized" and can cause the NMI entry code to run in the wrong way. Provide a non-ist entry point for VMX which shares the C-function with the regular NMI entry and invoke the new asm entry point instead. On 32-bit this just maps to the regular NMI entry point as 32-bit has no ISTs and is not affected. [ tglx: Made it independent for backporting, massaged changelog ] Fixes: 1a5488ef0d ("KVM: VMX: Invoke NMI handler via indirect call instead of INTn") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Lai Jiangshan <laijs@linux.alibaba.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/87r1imi8i1.ffs@nanos.tec.linutronix.de		2021-05-05 22:54:10 +02:00
..
boot	- turn the stack canary into a normal __percpu variable on 32-bit which	2021-04-27 17:45:09 -07:00
configs	module: remove EXPORT_UNUSED_SYMBOL*	2021-02-08 12:28:07 +01:00
crypto	Objtool updates in this cycle were:	2021-04-28 12:53:24 -07:00
entry	Add Landlock, a new LSM from Mickaël Salaün <mic@linux.microsoft.com>	2021-05-01 18:50:44 -07:00
events	IOMMU Updates for Linux v5.13	2021-05-01 09:33:00 -07:00
hyperv	The x86 MM changes in this cycle were:	2021-04-29 11:41:43 -07:00
ia32	x86/ia32_signal: Propagate __user annotation properly	2020-12-11 19:44:31 +01:00
include	KVM/VMX: Invoke NMI non-IST entry instead of IST entry	2021-05-05 22:54:10 +02:00
kernel	KVM/VMX: Invoke NMI non-IST entry instead of IST entry	2021-05-05 22:54:10 +02:00
kvm	KVM/VMX: Invoke NMI non-IST entry instead of IST entry	2021-05-05 22:54:10 +02:00
lib	- turn the stack canary into a normal __percpu variable on 32-bit which	2021-04-27 17:45:09 -07:00
math-emu	x86/fpu/math-emu: Fix function cast warning	2021-03-23 00:08:02 +01:00
mm	ARM:	2021-05-01 10:14:08 -07:00
net	Networking changes for 5.13.	2021-04-29 11:57:23 -07:00
pci	x86: Fix various typos in comments	2021-03-18 15:31:53 +01:00
platform	- turn the stack canary into a normal __percpu variable on 32-bit which	2021-04-27 17:45:09 -07:00
power	- turn the stack canary into a normal __percpu variable on 32-bit which	2021-04-27 17:45:09 -07:00
purgatory	crypto: sha - split sha.h into sha1.h and sha2.h	2020-11-20 14:45:33 +11:00
ras
realmode	x86: Fix various typos in comments, take #2	2021-03-21 23:50:28 +01:00
tools	x86/tools/insn_sanity: Convert to insn_decode()	2021-03-15 12:21:11 +01:00
um	um: remove process stub VMA	2021-02-12 21:37:38 +01:00
video
xen	The x86 MM changes in this cycle were:	2021-04-29 11:41:43 -07:00
.gitignore
Kbuild
Kconfig	mm/memtest: add ARCH_USE_MEMTEST	2021-04-30 11:20:36 -07:00
Kconfig.assembler
Kconfig.cpu
Kconfig.debug	x86, libnvdimm/test: Remove COPY_MC_TEST	2020-10-26 18:08:35 +01:00
Makefile	Kbuild updates for v5.13	2021-04-29 14:24:39 -07:00
Makefile_32.cpu
Makefile.um