Lai Jiangshan bfccc4eade KVM/VMX: Invoke NMI non-IST entry instead of IST entry ... commit a217a6593cec8b315d4c2f344bae33660b39b703 upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-05-19 10:12:51 +02:00
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alpha
arc	arc: kernel: Return -EFAULT if copy_to_user() fails	2021-04-21 13:00:51 +02:00
arm	ARM: dts: uniphier: Change phy-mode to RGMII-ID to enable delay pins for RTL8211E	2021-05-14 09:50:43 +02:00
arm64	arm64: Remove arm64_dma32_phys_limit and its uses	2021-05-14 09:50:46 +02:00
c6x
csky	csky: change a Kconfig symbol name to fix e1000 build error	2021-04-28 13:40:02 +02:00
h8300
hexagon
ia64	ia64: fix EFI_DEBUG build	2021-05-14 09:50:45 +02:00
m68k	m68k: Add missing mmap_read_lock() to sys_cacheflush()	2021-05-14 09:50:19 +02:00
microblaze
mips	MIPS: pci-legacy: stop using of_pci_range_to_resource	2021-05-14 09:50:39 +02:00
nds32
nios2
openrisc
parisc
powerpc	powerpc/52xx: Fix an invalid ASM expression ('addi' used instead of 'add')	2021-05-14 09:50:42 +02:00
riscv	riscv: Fix spelling mistake "SPARSEMEM" to "SPARSMEM"	2021-04-21 13:00:55 +02:00
s390	KVM: s390: extend kvm_s390_shadow_fault to return entry pointer	2021-05-14 09:50:03 +02:00
sh
sparc
um
x86	KVM/VMX: Invoke NMI non-IST entry instead of IST entry	2021-05-19 10:12:51 +02:00
xtensa
.gitignore
Kconfig