Thomas Gleixner 5ce6e5bd23 x86/smp: Enforce CONFIG_HOTPLUG_CPU when SMP=y ... commit bebd024e4815b1a170fcd21ead9c2222b23ce9e6 upstream. The SMT disable 'nosmt' command line argument is not working properly when CONFIG_HOTPLUG_CPU is disabled. The teardown of the sibling CPUs which are required to be brought up due to the MCE issues, cannot work. The CPUs are then kept in a half dead state. As the 'nosmt' functionality has become popular due to the speculative hardware vulnerabilities, the half torn down state is not a proper solution to the problem. Enforce CONFIG_HOTPLUG_CPU=y when SMP is enabled so the full operation is possible. Reported-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Mukesh Ojha <mojha@codeaurora.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Rik van Riel <riel@surriel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Micheal Kelley <michael.h.kelley@microsoft.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190326163811.598166056@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2019-04-03 06:23:28 +02:00
..
boot	x86/kaslr: Fix incorrect i8254 outb() parameters	2019-02-06 19:43:04 +01:00
configs
crypto	crypto: x86/chacha20 - avoid sleeping with preemption disabled	2019-01-13 10:05:32 +01:00
entry	x86/entry/64: Remove %ebx handling from error_entry/exit	2018-12-01 09:46:36 +01:00
ia32	x86/a.out: Clear the dump structure initially	2019-02-20 10:13:23 +01:00
include	Revert "x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls"	2019-03-23 08:44:28 +01:00
kernel	x86/kexec: Don't setup EFI info if EFI runtime is not enabled	2019-03-23 08:44:26 +01:00
kvm	KVM: X86: Fix residual mmio emulation request to userspace	2019-03-23 08:44:40 +01:00
lguest
lib	x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec	2018-12-17 21:55:14 +01:00
math-emu
mm	mm: replace get_user_pages() write/force parameters with gup_flags	2018-12-17 21:55:16 +01:00
net
oprofile
pci	x86/PCI: Fix Broadcom CNB20LE unintended sign extension (redux)	2019-02-20 10:13:04 +01:00
platform	Revert "x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls"	2019-03-23 08:44:28 +01:00
power
purgatory
ras
realmode
tools
um	um: Avoid longjmp/setjmp symbol clashes with libpthread.a	2018-11-10 07:41:35 -08:00
video
xen	xen: fix xen_qlock_wait()	2018-11-21 09:27:36 +01:00
.gitignore
Kbuild
Kconfig	x86/smp: Enforce CONFIG_HOTPLUG_CPU when SMP=y	2019-04-03 06:23:28 +02:00
Kconfig.cpu
Kconfig.debug
Makefile	x86/build: Use cc-option to validate stack alignment parameter	2018-11-27 16:08:00 +01:00
Makefile.um
Makefile_32.cpu