linux/arch
Andi Kleen cc51e5428e x86/speculation/l1tf: Increase l1tf memory limit for Nehalem+
On Nehalem and newer core CPUs the CPU cache internally uses 44 bits
physical address space. The L1TF workaround is limited by this internal
cache address width, and needs to have one bit free there for the
mitigation to work.

Older client systems report only 36bit physical address space so the range
check decides that L1TF is not mitigated for a 36bit phys/32GB system with
some memory holes.

But since these actually have the larger internal cache width this warning
is bogus because it would only really be needed if the system had more than
43bits of memory.

Add a new internal x86_cache_bits field. Normally it is the same as the
physical bits field reported by CPUID, but for Nehalem and newerforce it to
be at least 44bits.

Change the L1TF memory size warning to use the new cache_bits field to
avoid bogus warnings and remove the bogus comment about memory size.

Fixes: 17dbca1193 ("x86/speculation/l1tf: Add sysfs reporting for l1tf")
Reported-by: George Anchev <studio@anchev.net>
Reported-by: Christopher Snowhill <kode54@gmail.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Michael Hocko <mhocko@suse.com>
Cc: vbabka@suse.cz
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180824170351.34874-1-andi@firstfloor.org
2018-08-27 10:29:14 +02:00
..
alpha Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-08-24 09:25:39 -07:00
arc kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
arm ARM: SoC: late updates 2018-08-25 14:12:36 -07:00
arm64 ARM: SoC: late updates 2018-08-25 14:12:36 -07:00
c6x kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
h8300 Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
hexagon kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
ia64 ia64: Fix allnoconfig section mismatch for ioc_init/ioc_iommu_info 2018-08-22 14:12:47 -07:00
m68k kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
microblaze kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
mips Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
nds32 kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
nios2 mm: convert return type of handle_mm_fault() caller to vm_fault_t 2018-08-17 16:20:28 -07:00
openrisc OpenRISC updates for 4.19 2018-08-23 14:09:37 -07:00
parisc Merge branch 'parisc-4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2018-08-22 14:06:37 -07:00
powerpc Merge branch 'ida-4.19' of git://git.infradead.org/users/willy/linux-dax 2018-08-26 11:48:42 -07:00
riscv Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
s390 Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
sh kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
sparc Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
um kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
unicore32 mm: convert return type of handle_mm_fault() caller to vm_fault_t 2018-08-17 16:20:28 -07:00
x86 x86/speculation/l1tf: Increase l1tf memory limit for Nehalem+ 2018-08-27 10:29:14 +02:00
xtensa Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
.gitignore
Kconfig Merge branch 'tlb-fixes' 2018-08-23 14:55:01 -07:00