The "ENERGY_PERF_BIAS: Set to 'normal', was 'performance'" message triggers
on pretty much every Intel machine. The purpose of log messages with
a warning level is to notify the user of something which potentially is
a problem, or at least somewhat unexpected.

This message clearly does not match those criteria, so lower its log
priority from warning to info.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181230172715.17469-1-hdegoede@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Some of the recently added const tables use __initdata which causes section
attribute conflicts.

Use __initconst instead.

Fixes: fa1202ef2243 ("x86/speculation: Add command line control")
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190330004743.29541-9-andi@firstfloor.org

kernel_randomize_memory() uses __PHYSICAL_MASK_SHIFT to calculate
the maximum amount of system RAM supported. The size of the direct
mapping section is obtained from the smaller one of the below two
values:

(actual system RAM size + padding size) vs (max system RAM size supported)

This calculation is wrong since commit

b83ce5ee9147 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52").

In it, __PHYSICAL_MASK_SHIFT was changed to be 52, regardless of whether
the kernel is using 4-level or 5-level page tables. Thus, it will always
use 4 PB as the maximum amount of system RAM, even in 4-level paging
mode where it should actually be 64 TB.

Thus, the size of the direct mapping section will always
be the sum of the actual system RAM size plus the padding size.

Even when the amount of system RAM is 64 TB, the following layout will
still be used. Obviously KALSR will be weakened significantly.

|____|_______actual RAM_______|_padding_|______the rest_______|
0 64TB ~120TB

Instead, it should be like this:

|____|_______actual RAM_______|_________the rest______________|
0 64TB ~120TB

The size of padding region is controlled by
CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING, which is 10 TB by default.

The above issue only exists when
CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING is set to a non-zero value,
which is the case when CONFIG_MEMORY_HOTPLUG is enabled. Otherwise,
using __PHYSICAL_MASK_SHIFT doesn't affect KASLR.

Fix it by replacing __PHYSICAL_MASK_SHIFT with MAX_PHYSMEM_BITS.

[ bp: Massage commit message. ]

Fixes: b83ce5ee9147 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Garnier <thgarnie@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: frank.ramsay@hpe.com
Cc: herbert@gondor.apana.org.au
Cc: kirill@shutemov.name
Cc: mike.travis@hpe.com
Cc: thgarnie@google.com
Cc: x86-ml <x86@kernel.org>
Cc: yamada.masahiro@socionext.com
Link: https://lkml.kernel.org/r/20190417083536.GE7065@MiWiFi-R3L-srv

The Kconfig text contains a spelling mistake, fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20190416105751.18899-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Revert the following commit:

515ab7c41306: ("x86/mm: Align TLB invalidation info")

I found out (the hard way) that under some .config options (notably L1_CACHE_SHIFT=7)
and compiler combinations this on-stack alignment leads to a 320 byte
stack usage, which then triggers a KASAN stack warning elsewhere.

Using 320 bytes of stack space for a 40 byte structure is ludicrous and
clearly not right.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Nadav Amit <namit@vmware.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 515ab7c41306 ("x86/mm: Align TLB invalidation info")
Link: http://lkml.kernel.org/r/20190416080335.GM7905@worktop.programming.kicks-ass.net
[ Minor changelog edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Upon reboot, the Acer TravelMate X514-51T laptop appears to complete the
shutdown process, but then it hangs in BIOS POST with a black screen.

The problem is intermittent - at some points it has appeared related to
Secure Boot settings or different kernel builds, but ultimately we have
not been able to identify the exact conditions that trigger the issue to
come and go.

Besides, the EFI mode cannot be disabled in the BIOS of this model.

However, after extensive testing, we observe that using the EFI reboot
method reliably avoids the issue in all cases.

So add a boot time quirk to use EFI reboot on such systems.

Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=203119
Signed-off-by: Jian-Hong Pan <jian-hong@endlessm.com>
Signed-off-by: Daniel Drake <drake@endlessm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Cc: linux@endlessm.com
Link: http://lkml.kernel.org/r/20190412080152.3718-1-jian-hong@endlessm.com
[ Fix !CONFIG_EFI build failure, clarify the code and the changelog a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Xose Vazquez Perez reported boot warnings when NX is disabled on the kernel command line.

__early_set_fixmap() triggers this warning:

attempted to set unsupported pgprot: 8000000000000163
bits: 8000000000000000
supported: 7fffffffffffffff

WARNING: CPU: 0 PID: 0 at arch/x86/include/asm/pgtable.h:537
__early_set_fixmap+0xa2/0xff

because it uses __default_kernel_pte_mask to mask out unsupported bits.

Use __supported_pte_mask instead.

Disabling NX on the command line also triggers the NX warning in the page
table mapping check:

WARNING: CPU: 1 PID: 1 at arch/x86/mm/dump_pagetables.c:262 note_page+0x2ae/0x650
....

Make the warning depend on NX set in __supported_pte_mask.

Reported-by: Xose Vazquez Perez <xose.vazquez@gmail.com>
Tested-by: Xose Vazquez Perez <xose.vazquez@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1904151037530.1729@nanos.tec.linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

With CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y, we compile the kernel with
-fdata-sections, which also splits the .bss section.

The new section, with a new .bss.* name, which pattern gets missed by the
main x86 linker script which only expects the '.bss' name. This results
in the discarding of the second part and a too small, truncated .bss
section and an unhappy, non-working kernel.

Use the common BSS_MAIN macro in the linker script to properly capture
and merge all the generated BSS sections.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20190415164956.124067-1-samitolvanen@google.com
[ Extended the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Mikhail reported a lockdep splat related to the AMD specific ssb_state
lock:

CPU0 CPU1
lock(&st->lock);
local_irq_disable();
lock(&(&sighand->siglock)->rlock);
lock(&st->lock);
<Interrupt>
lock(&(&sighand->siglock)->rlock);

*** DEADLOCK ***

The connection between sighand->siglock and st->lock comes through seccomp,
which takes st->lock while holding sighand->siglock.

Make sure interrupts are disabled when __speculation_ctrl_update() is
invoked via prctl() -> speculation_ctrl_update(). Add a lockdep assert to
catch future offenders.

Fixes: 1f50ddb4f418 ("x86/speculation: Handle HT correctly on AMD")
Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Cc: Thomas Lendacky <thomas.lendacky@amd.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1904141948200.4917@nanos.tec.linutronix.de

When cache allocation is supported and the user creates a new resctrl
resource group, the allocations of the new resource group are
initialized to all regions that it can possibly use. At this time these
regions are all that are shareable by other resource groups as well as
regions that are not currently used. The new resource group's mode is
also initialized to reflect this initialization and set to "shareable".

The new resource group's mode is currently repeatedly initialized within
the loop that configures the hardware with the resource group's default
allocations.

Move the initialization of the resource group's mode outside the
hardware configuration loop. The resource group's mode is now
initialized only once as the final step to reflect that its configured
allocations are "shareable".

Fixes: 95f0b77efa57 ("x86/intel_rdt: Initialize new resource group with sane defaults")
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: pei.p.jia@intel.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1554839629-5448-1-git-send-email-xiaochen.shen@intel.com

There's a number of problems with how arch/x86/include/asm/bitops.h
is currently using assembly constraints for the memory region
bitops are modifying:

1) Use memory clobber in bitops that touch arbitrary memory

Certain bit operations that read/write bits take a base pointer and an
arbitrarily large offset to address the bit relative to that base.
Inline assembly constraints aren't expressive enough to tell the
compiler that the assembly directive is going to touch a specific memory
location of unknown size, therefore we have to use the "memory" clobber
to indicate that the assembly is going to access memory locations other
than those listed in the inputs/outputs.

To indicate that BTR/BTS instructions don't necessarily touch the first
sizeof(long) bytes of the argument, we also move the address to assembly
inputs.

This particular change leads to size increase of 124 kernel functions in
a defconfig build. For some of them the diff is in NOP operations, other
end up re-reading values from memory and may potentially slow down the
execution. But without these clobbers the compiler is free to cache
the contents of the bitmaps and use them as if they weren't changed by
the inline assembly.

2) Use byte-sized arguments for operations touching single bytes.

Passing a long value to ANDB/ORB/XORB instructions makes the compiler
treat sizeof(long) bytes as being clobbered, which isn't the case. This
may theoretically lead to worse code in the case of heavy optimization.

Practical impact:

I've built a defconfig kernel and looked through some of the functions
generated by GCC 7.3.0 with and without this clobber, and didn't spot
any miscompilations.

However there is a (trivial) theoretical case where this code leads to
miscompilation:

https://lkml.org/lkml/2019/3/28/393

using just GCC 8.3.0 with -O2. It isn't hard to imagine someone writes
such a function in the kernel someday.

So the primary motivation is to fix an existing misuse of the asm
directive, which happens to work in certain configurations now, but
isn't guaranteed to work under different circumstances.

[ --mingo: Added -stable tag because defconfig only builds a fraction
of the kernel and the trivial testcase looks normal enough to
be used in existing or in-development code. ]

Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: James Y Knight <jyknight@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20190402112813.193378-1-glider@google.com
[ Edited the changelog, tidied up one of the defines. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

The user can control the MBA memory bandwidth in MBps (Mega
Bytes per second) units of the MBA Software Controller (mba_sc)
by using the "mba_MBps" mount option. For details, see
Documentation/x86/resctrl_ui.txt.

However, commit

23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context")

changed the mount option name from "mba_MBps" to "mba_mpbs" by mistake.

Change it back from to "mba_MBps" because it is user-visible, and
correct "Opt_mba_mpbs" spelling to "Opt_mba_mbps".

[ bp: massage commit message. ]

Fixes: 23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context")
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: dhowells@redhat.com
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: pei.p.jia@intel.com
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1553896238-22130-1-git-send-email-xiaochen.shen@intel.com

Remove the unused @size argument and move it into a header file, so it
can be inlined.

[ bp: Massage. ]

Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-efi <linux-efi@vger.kernel.org>
Cc: platform-driver-x86@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190328114233.27835-1-mcroce@redhat.com