linux/arch
Thomas Gleixner e261f209c3 x86/speculation/mds: Add BUG_MSBDS_ONLY
This bug bit is set on CPUs which are only affected by Microarchitectural
Store Buffer Data Sampling (MSBDS) and not by any other MDS variant.

This is important because the Store Buffers are partitioned between
Hyper-Threads so cross thread forwarding is not possible. But if a thread
enters or exits a sleep state the store buffer is repartitioned which can
expose data from one thread to the other. This transition can be mitigated.

That means that for CPUs which are only affected by MSBDS SMT can be
enabled, if the CPU is not affected by other SMT sensitive vulnerabilities,
e.g. L1TF. The XEON PHI variants fall into that category. Also the
Silvermont/Airmont ATOMs, but for them it's not really relevant as they do
not support SMT, but mark them for completeness sake.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:11 +01:00
..
alpha alpha: fix page fault handling for r16-r18 targets 2019-02-10 20:42:23 -08:00
arc ARCv2: don't assume core 0x54 has dual issue 2019-02-21 14:53:36 -08:00
arm ARM: SoC fixes for v5.0 2019-03-02 16:43:15 -08:00
arm64 ARM: SoC fixes for v5.0 2019-03-02 16:43:15 -08:00
c6x arch: unexport asm/shmparam.h for all architectures 2019-02-01 15:46:22 -08:00
csky csky: Fixup dead loop in show_stack 2019-02-13 09:48:14 +08:00
h8300 arch: unexport asm/shmparam.h for all architectures 2019-02-01 15:46:22 -08:00
hexagon arch: unexport asm/shmparam.h for all architectures 2019-02-01 15:46:22 -08:00
ia64 ia64: remove redundant 'export AWK' 2019-01-16 23:31:18 +09:00
m68k for-linus-20190209 2019-02-09 10:26:09 -08:00
microblaze arch: unexport asm/shmparam.h for all architectures 2019-02-01 15:46:22 -08:00
mips Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-02 08:46:34 -08:00
nds32 nds32: remove unneeded code in arch/nds32/Makefile 2019-01-17 23:42:37 +09:00
nios2 arch: remove redundant UAPI generic-y defines 2019-01-06 10:22:15 +09:00
openrisc arch: unexport asm/shmparam.h for all architectures 2019-02-01 15:46:22 -08:00
parisc parisc: Fix ptrace syscall number modification 2019-02-21 20:10:46 +01:00
powerpc powerpc fixes for 5.0 #6 2019-02-23 11:13:50 -08:00
riscv Revert "RISC-V: Make BSS section as the last section in vmlinux.lds.S" 2019-02-11 15:24:45 -08:00
s390 KVM: s390: Fix crypto handling for nested KVM 2019-02-20 23:48:55 +01:00
sh sh: fix build error for invisible CONFIG_BUILTIN_DTB_SOURCE 2019-02-13 23:29:42 +09:00
sparc arch: remove redundant UAPI generic-y defines 2019-01-06 10:22:15 +09:00
um Merge branch 'akpm' (patches from Andrew) 2019-01-05 09:16:18 -08:00
unicore32 arch: unexport asm/shmparam.h for all architectures 2019-02-01 15:46:22 -08:00
x86 x86/speculation/mds: Add BUG_MSBDS_ONLY 2019-03-06 21:52:11 +01:00
xtensa xtensa: SMP: limit number of possible CPUs by NR_CPUS 2019-01-27 10:04:30 -08:00
.gitignore
Kconfig jump_label: move 'asm goto' support test to Kconfig 2019-01-06 09:46:51 +09:00