linux/arch/x86
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
..
boot Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
configs
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-08-15 16:01:47 -07:00
entry x86/vdso: Fix vDSO build if a retpoline is emitted 2018-08-20 18:04:41 +02:00
events Merge branch 'perf/urgent' into perf/core, to pick up fixes 2018-08-02 09:59:20 +02:00
hyperv x86/mm: Only use tlb_remove_table() for paravirt 2018-08-23 11:56:31 -07:00
ia32 syscalls/x86: auto-create compat_sys_*() prototypes 2018-04-02 20:16:18 +02:00
include x86/speculation/l1tf: Increase l1tf memory limit for Nehalem+ 2018-08-27 10:29:14 +02:00
kernel x86/speculation/l1tf: Increase l1tf memory limit for Nehalem+ 2018-08-27 10:29:14 +02:00
kvm Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-26 10:13:21 -07:00
lib x86/asm/64: Use 32-bit XOR to zero registers 2018-07-03 09:59:29 +02:00
math-emu
mm Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-26 11:25:21 -07:00
net bpf, x32: Fix regression caused by commit 24dea04767 2018-07-26 02:51:12 +02:00
oprofile x86/oprofile: Fix bogus GCC-8 warning in nmi_setup() 2018-02-21 09:54:17 +01:00
pci PCI: Make early dump functionality generic 2018-06-29 20:06:07 -05:00
platform Merge branch 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-14 09:46:06 -07:00
power Power management updates for 4.19-rc1 2018-08-14 13:12:24 -07:00
purgatory kbuild: move bin2c back to scripts/ from scripts/basic/ 2018-07-18 01:18:05 +09:00
ras
realmode x86-64/realmode: Add instruction suffix 2018-02-20 09:33:41 +01:00
tools x86/relocs: Add __end_rodata_aligned to S_REL 2018-08-09 20:42:07 +02:00
um Consolidation of Kconfig files by Christoph Hellwig. 2018-08-15 13:05:12 -07:00
video
xen Merge branch 'tlb-fixes' 2018-08-23 14:55:01 -07:00
.gitignore x86/build: Add arch/x86/tools/insn_decoder_test to .gitignore 2018-02-13 14:10:29 +01:00
Kbuild
Kconfig x86/mm: Only use tlb_remove_table() for paravirt 2018-08-23 11:56:31 -07:00
Kconfig.cpu Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-03-25 07:36:02 -10:00
Kconfig.debug Kconfig: consolidate the "Kernel hacking" menu 2018-08-02 08:06:48 +09:00
Makefile kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
Makefile_32.cpu
Makefile.um kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00