linux/arch/x86
Thomas Gleixner a74cfffb03 x86/speculation: Rework SMT state change
arch_smt_update() is only called when the sysfs SMT control knob is
changed. This means that when SMT is enabled in the sysfs control knob the
system is considered to have SMT active even if all siblings are offline.

To allow finegrained control of the speculation mitigations, the actual SMT
state is more interesting than the fact that siblings could be enabled.

Rework the code, so arch_smt_update() is invoked from each individual CPU
hotplug function, and simplify the update function while at it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185004.521974984@linutronix.de
2018-11-28 11:57:07 +01:00
..
boot x86: Clean up 'sizeof x' => 'sizeof(x)' 2018-10-29 07:13:28 +01:00
configs x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y 2018-10-10 08:29:51 +02:00
crypto crypto: x86/aes-ni - fix build error following fpu template removal 2018-10-08 13:47:02 +08:00
entry New gcc plugin: stackleak 2018-11-01 11:46:27 -07:00
events perf/x86/intel/uncore: Support CoffeeLake 8th CBOX 2018-11-12 05:03:26 +01:00
hyperv Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 17:54:58 +01:00
ia32
include x86/speculation: Rename SSBD update functions 2018-11-28 11:57:06 +01:00
kernel x86/speculation: Rework SMT state change 2018-11-28 11:57:07 +01:00
kvm x86: Clean up 'sizeof x' => 'sizeof(x)' 2018-10-29 07:13:28 +01:00
lib Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 15:24:22 +01:00
math-emu
mm Merge branch 'core/urgent' into x86/urgent, to pick up objtool fix 2018-11-03 23:42:16 +01:00
net bpf, x32: Fix regression caused by commit 24dea04767 2018-07-26 02:51:12 +02:00
oprofile
pci mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
platform memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
power mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
purgatory
ras
realmode
tools x86: Clean up 'sizeof x' => 'sizeof(x)' 2018-10-29 07:13:28 +01:00
um Merge branch 'core/urgent' into x86/urgent, to pick up objtool fix 2018-11-03 23:42:16 +01:00
video
xen Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-11 16:41:50 -06:00
.gitignore
Kbuild
Kconfig x86/Kconfig: Select SCHED_SMT if SMP enabled 2018-11-28 11:57:07 +01:00
Kconfig.cpu x86/cpu: Create Hygon Dhyana architecture support file 2018-09-27 16:14:05 +02:00
Kconfig.debug x86/kconfig: Remove redundant 'default n' lines from all x86 Kconfig's 2018-10-17 08:39:42 +02:00
Makefile x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support 2018-11-28 11:57:03 +01:00
Makefile_32.cpu
Makefile.um kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00