pad instructions and thus make using the alternatives macros more
straightforward and without having to figure out old and new instruction
sizes but have the toolchain figure that out for us.
Furthermore, it optimizes JMPs used so that fetch and decode can be
relieved with smaller versions of the JMPs, where possible.
Some stats:
x86_64 defconfig:
Alternatives sites total: 2478
Total padding added (in Bytes): 6051
The padding is currently done for:
X86_FEATURE_ALWAYS
X86_FEATURE_ERMS
X86_FEATURE_LFENCE_RDTSC
X86_FEATURE_MFENCE_RDTSC
X86_FEATURE_SMAP
This is with the latest version of the patchset. Of course, on each
machine the alternatives sites actually being patched are a proper
subset of the total number.
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Merge tag 'alternatives_padding' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp into x86/asm
Pull alternative instructions framework improvements from Borislav Petkov:
"A more involved rework of the alternatives framework to be able to
pad instructions and thus make using the alternatives macros more
straightforward and without having to figure out old and new instruction
sizes but have the toolchain figure that out for us.
Furthermore, it optimizes JMPs used so that fetch and decode can be
relieved with smaller versions of the JMPs, where possible.
Some stats:
x86_64 defconfig:
Alternatives sites total: 2478
Total padding added (in Bytes): 6051
The padding is currently done for:
X86_FEATURE_ALWAYS
X86_FEATURE_ERMS
X86_FEATURE_LFENCE_RDTSC
X86_FEATURE_MFENCE_RDTSC
X86_FEATURE_SMAP
This is with the latest version of the patchset. Of course, on each
machine the alternatives sites actually being patched are a proper
subset of the total number."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Up until now we had to pay attention to relative JMPs in alternatives
about how their relative offset gets computed so that the jump target
is still correct. Or, as it is the case for near CALLs (opcode e8), we
still have to go and readjust the offset at patching time.
What is more, the static_cpu_has_safe() facility had to forcefully
generate 5-byte JMPs since we couldn't rely on the compiler to generate
properly sized ones so we had to force the longest ones. Worse than
that, sometimes it would generate a replacement JMP which is longer than
the original one, thus overwriting the beginning of the next instruction
at patching time.
So, in order to alleviate all that and make using JMPs more
straight-forward we go and pad the original instruction in an
alternative block with NOPs at build time, should the replacement(s) be
longer. This way, alternatives users shouldn't pay special attention
so that original and replacement instruction sizes are fine but the
assembler would simply add padding where needed and not do anything
otherwise.
As a second aspect, we go and recompute JMPs at patching time so that we
can try to make 5-byte JMPs into two-byte ones if possible. If not, we
still have to recompute the offsets as the replacement JMP gets put far
away in the .altinstr_replacement section leading to a wrong offset if
copied verbatim.
For example, on a locally generated kernel image
old insn VA: 0xffffffff810014bd, CPU feat: X86_FEATURE_ALWAYS, size: 2
__switch_to:
ffffffff810014bd: eb 21 jmp ffffffff810014e0
repl insn: size: 5
ffffffff81d0b23c: e9 b1 62 2f ff jmpq ffffffff810014f2
gets corrected to a 2-byte JMP:
apply_alternatives: feat: 3*32+21, old: (ffffffff810014bd, len: 2), repl: (ffffffff81d0b23c, len: 5)
alt_insn: e9 b1 62 2f ff
recompute_jumps: next_rip: ffffffff81d0b241, tgt_rip: ffffffff810014f2, new_displ: 0x00000033, ret len: 2
converted to: eb 33 90 90 90
and a 5-byte JMP:
old insn VA: 0xffffffff81001516, CPU feat: X86_FEATURE_ALWAYS, size: 2
__switch_to:
ffffffff81001516: eb 30 jmp ffffffff81001548
repl insn: size: 5
ffffffff81d0b241: e9 10 63 2f ff jmpq ffffffff81001556
gets shortened into a two-byte one:
apply_alternatives: feat: 3*32+21, old: (ffffffff81001516, len: 2), repl: (ffffffff81d0b241, len: 5)
alt_insn: e9 10 63 2f ff
recompute_jumps: next_rip: ffffffff81d0b246, tgt_rip: ffffffff81001556, new_displ: 0x0000003e, ret len: 2
converted to: eb 3e 90 90 90
... and so on.
This leads to a net win of around
40ish replacements * 3 bytes savings =~ 120 bytes of I$
on an AMD guest which means some savings of precious instruction cache
bandwidth. The padding to the shorter 2-byte JMPs are single-byte NOPs
which on smart microarchitectures means discarding NOPs at decode time
and thus freeing up execution bandwidth.
Signed-off-by: Borislav Petkov <bp@suse.de>
Up until now we have always paid attention to make sure the length of
the new instruction replacing the old one is at least less or equal to
the length of the old instruction. If the new instruction is longer, at
the time it replaces the old instruction it will overwrite the beginning
of the next instruction in the kernel image and cause your pants to
catch fire.
So instead of having to pay attention, teach the alternatives framework
to pad shorter old instructions with NOPs at buildtime - but only in the
case when
len(old instruction(s)) < len(new instruction(s))
and add nothing in the >= case. (In that case we do add_nops() when
patching).
This way the alternatives user shouldn't have to care about instruction
sizes and simply use the macros.
Add asm ALTERNATIVE* flavor macros too, while at it.
Also, we need to save the pad length in a separate struct alt_instr
member for NOP optimization and the way to do that reliably is to carry
the pad length instead of trying to detect whether we're looking at
single-byte NOPs or at pathological instruction offsets like e9 90 90 90
90, for example, which is a valid instruction.
Thanks to Michael Matz for the great help with toolchain questions.
Signed-off-by: Borislav Petkov <bp@suse.de>
Add support for the new pcommit (persistent commit) instruction.
This instruction was announced in the document "Intel
Architecture Instruction Set Extensions Programming Reference"
with reference number 319433-022:
https://software.intel.com/sites/default/files/managed/0d/53/319433-022.pdf
The pcommit instruction ensures that data that has been flushed
from the processor's cache hierarchy with clwb, clflushopt or
clflush is accepted to memory and is durable on the DIMM. The
primary use case for this is persistent memory.
This function shows how to properly use clwb/clflushopt/clflush
and pcommit with appropriate fencing:
void flush_and_commit_buffer(void *vaddr, unsigned int size)
{
void *vend = vaddr + size - 1;
for (; vaddr < vend; vaddr += boot_cpu_data.x86_clflush_size)
clwb(vaddr);
/* Flush any possible final partial cacheline */
clwb(vend);
/*
* sfence to order clwb/clflushopt/clflush cache flushes
* mfence via mb() also works
*/
wmb();
/* pcommit and the required sfence for ordering */
pcommit_sfence();
}
After this function completes the data pointed to by vaddr is
has been accepted to memory and will be durable if the vaddr
points to persistent memory.
Pcommit must always be ordered by an mfence or sfence, so to
help simplify things we include both the pcommit and the
required sfence in the alternatives generated by
pcommit_sfence(). The other option is to keep them separated,
but on platforms that don't support pcommit this would then turn
into:
void flush_and_commit_buffer(void *vaddr, unsigned int size)
{
void *vend = vaddr + size - 1;
for (; vaddr < vend; vaddr += boot_cpu_data.x86_clflush_size)
clwb(vaddr);
/* Flush any possible final partial cacheline */
clwb(vend);
/*
* sfence to order clwb/clflushopt/clflush cache flushes
* mfence via mb() also works
*/
wmb();
nop(); /* from pcommit(), via alternatives */
/*
* sfence to order pcommit
* mfence via mb() also works
*/
wmb();
}
This is still correct, but now you've got two fences separated
by only a nop. With the commit and the fence together in
pcommit_sfence() you avoid the final unneeded fence.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1424367448-24254-1-git-send-email-ross.zwisler@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The new hw_breakpoint bits are now ready for v3.20, merge them
into the main branch, to avoid conflicts.
Conflicts:
tools/perf/Documentation/perf-record.txt
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add support of Hardware Managed Performance States (HWP) described in Volume 3
section 14.4 of the SDM.
One bit CPUID.06H:EAX[bit 7] expresses the presence of the HWP feature on
the processor. The remaining bits CPUID.06H:EAX[bit 8-11] denote the
presense of various HWP features.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull x86 cpufeature updates from Ingo Molnar:
"This tree includes the following changes:
- Introduce DISABLED_MASK to list disabled CPU features, to simplify
CPU feature handling and avoid excessive #ifdefs
- Remove the lightly used cpu_has_pae() primitive"
* 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Add more disabled features
x86: Introduce disabled-features
x86: Axe the lightly-used cpu_has_pae
Apart from the usual cleanups, here is the summary of new features:
- s390 moves closer towards host large page support
- PowerPC has improved support for debugging (both inside the guest and
via gdbstub) and support for e6500 processors
- ARM/ARM64 support read-only memory (which is necessary to put firmware
in emulated NOR flash)
- x86 has the usual emulator fixes and nested virtualization improvements
(including improved Windows support on Intel and Jailhouse hypervisor
support on AMD), adaptive PLE which helps overcommitting of huge guests.
Also included are some patches that make KVM more friendly to memory
hot-unplug, and fixes for rare caching bugs.
Two patches have trivial mm/ parts that were acked by Rik and Andrew.
Note: I will soon switch to a subkey for signing purposes. To verify
future signed pull requests from me, please update my key with
"gpg --recv-keys 9B4D86F2". You should see 3 new subkeys---the
one for signing will be a 2048-bit RSA key, 4E6B09D7.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"Fixes and features for 3.18.
Apart from the usual cleanups, here is the summary of new features:
- s390 moves closer towards host large page support
- PowerPC has improved support for debugging (both inside the guest
and via gdbstub) and support for e6500 processors
- ARM/ARM64 support read-only memory (which is necessary to put
firmware in emulated NOR flash)
- x86 has the usual emulator fixes and nested virtualization
improvements (including improved Windows support on Intel and
Jailhouse hypervisor support on AMD), adaptive PLE which helps
overcommitting of huge guests. Also included are some patches that
make KVM more friendly to memory hot-unplug, and fixes for rare
caching bugs.
Two patches have trivial mm/ parts that were acked by Rik and Andrew.
Note: I will soon switch to a subkey for signing purposes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (157 commits)
kvm: do not handle APIC access page if in-kernel irqchip is not in use
KVM: s390: count vcpu wakeups in stat.halt_wakeup
KVM: s390/facilities: allow TOD-CLOCK steering facility bit
KVM: PPC: BOOK3S: HV: CMA: Reserve cma region only in hypervisor mode
arm/arm64: KVM: Report correct FSC for unsupported fault types
arm/arm64: KVM: Fix VTTBR_BADDR_MASK and pgd alloc
kvm: Fix kvm_get_page_retry_io __gup retval check
arm/arm64: KVM: Fix set_clear_sgi_pend_reg offset
kvm: x86: Unpin and remove kvm_arch->apic_access_page
kvm: vmx: Implement set_apic_access_page_addr
kvm: x86: Add request bit to reload APIC access page address
kvm: Add arch specific mmu notifier for page invalidation
kvm: Rename make_all_cpus_request() to kvm_make_all_cpus_request() and make it non-static
kvm: Fix page ageing bugs
kvm/x86/mmu: Pass gfn and level to rmapp callback.
x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only
kvm: x86: use macros to compute bank MSRs
KVM: x86: Remove debug assertion of non-PAE reserved bits
kvm: don't take vcpu mutex for obviously invalid vcpu ioctls
kvm: Faults which trigger IO release the mmap_sem
...
On x86_64, kernel text mappings are mapped read-only with CONFIG_DEBUG_RODATA.
In that case, KVM will fail to patch VMCALL instructions to VMMCALL
as required on AMD processors.
The failure mode is currently a divide-by-zero exception, which obviously
is a KVM bug that has to be fixed. However, picking the right instruction
between VMCALL and VMMCALL will be faster and will help if you cannot upgrade
the hypervisor.
Reported-by: Chris Webb <chris@arachsys.com>
Tested-by: Chris Webb <chris@arachsys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The original motivation for these patches was for an Intel CPU
feature called MPX. The patch to add a disabled feature for it
will go in with the other parts of the support.
But, in the meantime, there are a few other features than MPX
that we can make assumptions about at compile-time based on
compile options. Add them to disabled-features.h and check them
with cpu_feature_enabled().
Note that this gets rid of the last things that needed an #ifdef
CONFIG_X86_64 in cpufeature.h. Yay!
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140911211524.C0EC332A@viggo.jf.intel.com
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
I believe the REQUIRED_MASK aproach was taken so that it was
easier to consult in assembly (arch/x86/kernel/verify_cpu.S).
DISABLED_MASK does not have the same restriction, but I
implemented it the same way for consistency.
We have a REQUIRED_MASK... which does two things:
1. Keeps a list of cpuid bits to check in very early boot and
refuse to boot if those are not present.
2. Consulted during cpu_has() checks, which allows us to
optimize out things at compile-time. In other words, if we
*KNOW* we will not boot with the feature off, then we can
safely assume that it will be present forever.
But, we don't have a similar mechanism for CPU features which
may be present but that we know we will not use. We simply
use our existing mechanisms to repeatedly check the status of
the bit at runtime (well, the alternatives patching helps here
but it does not provide compile-time optimization).
Adding a feature to disabled-features.h allows the bit to be
checked via a new macro: cpu_feature_enabled(). Note that
for features in DISABLED_MASK, checks with this macro have
all of the benefits of an #ifdef. Before, we would have done
this in a header:
#ifdef CONFIG_X86_INTEL_MPX
#define cpu_has_mpx cpu_has(X86_FEATURE_MPX)
#else
#define cpu_has_mpx 0
#endif
and this in the code:
if (cpu_has_mpx)
do_some_mpx_thing();
Now, just add your feature to DISABLED_MASK and you can do this
everywhere, and get the same benefits you would have from
#ifdefs:
if (cpu_feature_enabled(X86_FEATURE_MPX))
do_some_mpx_thing();
We need a new function and *not* a modification to cpu_has()
because there are cases where we actually need to check the CPU
itself, despite what features the kernel supports. The best
example of this is a hypervisor which has no control over what
features its guests are using and where the guest does not depend
on the host for support.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140911211513.9E35E931@viggo.jf.intel.com
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
cpu_has_pae is only referenced in one place: the X86_32 kexec
code (in a file not even built on 64-bit). It hardly warrants
its own macro, or the trouble we go to ensuring that it can't
be called in X86_64 code.
Axe the macro and replace it with a direct cpu feature check.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140911211511.AD76E774@viggo.jf.intel.com
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The table mapping CPUID bits to human-readable strings takes up a
non-trivial amount of space, and only exists to support /proc/cpuinfo
and a couple of kernel messages. Since programs depend on the format of
/proc/cpuinfo, force inclusion of the table when building with /proc
support; otherwise, support omitting that table to save space, in which
case the kernel messages will print features numerically instead.
In addition to saving 1408 bytes out of vmlinux, this also saves 1373
bytes out of the uncompressed setup code, which contributes directly to
the size of bzImage.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Dump the flags which denote we have detected and/or have applied bug
workarounds to the CPU we're executing on, in a similar manner to the
feature flags.
The advantage is that those are not accumulating over time like the CPU
features.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1403609105-8332-2-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
X86_FEATURE_FXSAVE_LEAK, X86_FEATURE_11AP and
X86_FEATURE_CLFLUSH_MONITOR are not really features but synthetic bits
we use for applying different bug workarounds. Call them what they
really are, and make sure they get the proper cross-CPU behavior (OR
rather than AND).
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1403042783-23278-1-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Detect the xsaveopt, xsavec, xgetbv, and xsaves features in processor extended
state enumberation sub-leaf (eax=0x0d, ecx=1):
Bit 00: XSAVEOPT is available
Bit 01: Supports XSAVEC and the compacted form of XRSTOR if set
Bit 02: Supports XGETBV with ECX = 1 if set
Bit 03: Supports XSAVES/XRSTORS and IA32_XSS if set
The above features are defined in the new word 10 in cpu features.
The IA32_XSS MSR (index DA0H) contains a state-component bitmap that specifies
the state components that software has enabled xsaves and xrstors to manage.
If the bit corresponding to a state component is clear in XCR0 | IA32_XSS,
xsaves and xrstors will not operate on that state component, regardless of
the value of the instruction mask.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1401387164-43416-3-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
In each X86 feature macro definition, add one space in front of the word
number which is a one-digit number currently.
The purpose of reformatting the macros is to align one-digit and two-digit
word numbers.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1401387164-43416-2-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Here's the big driver core / sysfs update for 3.15-rc1.
Lots of kernfs updates to make it useful for other subsystems, and a few
other tiny driver core patches.
All have been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and sysfs updates from Greg KH:
"Here's the big driver core / sysfs update for 3.15-rc1.
Lots of kernfs updates to make it useful for other subsystems, and a
few other tiny driver core patches.
All have been in linux-next for a while"
* tag 'driver-core-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (42 commits)
Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()"
kernfs: cache atomic_write_len in kernfs_open_file
numa: fix NULL pointer access and memory leak in unregister_one_node()
Revert "driver core: synchronize device shutdown"
kernfs: fix off by one error.
kernfs: remove duplicate dir.c at the top dir
x86: align x86 arch with generic CPU modalias handling
cpu: add generic support for CPU feature based module autoloading
sysfs: create bin_attributes under the requested group
driver core: unexport static function create_syslog_header
firmware: use power efficient workqueue for unloading and aborting fw load
firmware: give a protection when map page failed
firmware: google memconsole driver fixes
firmware: fix google/gsmi duplicate efivars_sysfs_init()
drivers/base: delete non-required instances of include <linux/init.h>
kernfs: fix kernfs_node_from_dentry()
ACPI / platform: drop redundant ACPI_HANDLE check
kernfs: fix hash calculation in kernfs_rename_ns()
kernfs: add CONFIG_KERNFS
sysfs, kobject: add sysfs wrapper for kernfs_enable_ns()
...
We call this "clflush" in /proc/cpuinfo, and have
cpu_has_clflush()... let's be consistent and just call it that.
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-mlytfzjkvuf739okyn40p8a5@git.kernel.org
The x86 CPU feature modalias handling existed before it was reimplemented
generically. This patch aligns the x86 handling so that it
(a) reuses some more code that is now generic;
(b) uses the generic format for the modalias module metadata entry, i.e., it
now uses 'cpu:type:x86,venVVVVfamFFFFmodMMMM:feature:,XXXX,YYYY' instead of
the 'x86cpu:vendor:VVVV👪FFFF:model:MMMM:feature:,XXXX,YYYY' that was
used before.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Define the Intel MPX (Memory Protection Extensions) CPU feature flag
in the cpufeature list.
Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Link: http://lkml.kernel.org/r/1386375658-2191-2-git-send-email-qiaowei.ren@intel.com
Signed-off-by: Xudong Hao <xudong.hao@intel.com>
Signed-off-by: Liu Jinsong <jinsong.liu@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Fengguang Wu, Oleg Nesterov and Peter Zijlstra tracked down
a kernel crash to a GCC bug: GCC miscompiles certain 'asm goto'
constructs, as outlined here:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
Implement a workaround suggested by Jakub Jelinek.
Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Suggested-by: Jakub Jelinek <jakub@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
... for checking for "asm goto" compiler support. It is more explicit
this way and we cover the cases where distros have backported that
support even to gcc versions < 4.5.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1372437701-13351-1-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
We want to use this in early code where alternatives might not have run
yet and for that case we fall back to the dynamic boot_cpu_has.
For that, force a 5-byte jump since the compiler could be generating
differently sized jumps for each label.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1370772454-6106-5-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
static_cpu_has may be used only after alternatives have run. Before that
it always returns false if constant folding with __builtin_constant_p()
doesn't happen. And you don't want that.
This patch is the result of me debugging an issue where I overzealously
put static_cpu_has in code which executed before alternatives have run
and had to spend some time with scratching head and cursing at the
monitor.
So add a jump to a warning which screams loudly when we use this
function too early. The alternatives patch that check away in
conjunction with patching the rest of the kernel image.
[ hpa: factored this into its own configuration option. If we want to
have an overarching option, it should be an option which selects
other options, not as a group option in the source code. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1370772454-6106-4-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull crypto update from Herbert Xu:
- XTS mode optimisation for twofish/cast6/camellia/aes on x86
- AVX2/x86_64 implementation for blowfish/twofish/serpent/camellia
- SSSE3/AVX/AVX2 optimisations for sha256/sha512
- Added driver for SAHARA2 crypto accelerator
- Fix for GMAC when used in non-IPsec secnarios
- Added generic CMAC implementation (including IPsec glue)
- IP update for crypto/atmel
- Support for more than one device in hwrng/timeriomem
- Added Broadcom BCM2835 RNG driver
- Misc fixes
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (59 commits)
crypto: caam - fix job ring cleanup code
crypto: camellia - add AVX2/AES-NI/x86_64 assembler implementation of camellia cipher
crypto: serpent - add AVX2/x86_64 assembler implementation of serpent cipher
crypto: twofish - add AVX2/x86_64 assembler implementation of twofish cipher
crypto: blowfish - add AVX2/x86_64 implementation of blowfish cipher
crypto: tcrypt - add async cipher speed tests for blowfish
crypto: testmgr - extend camellia test-vectors for camellia-aesni/avx2
crypto: aesni_intel - fix Kconfig problem with CRYPTO_GLUE_HELPER_X86
crypto: aesni_intel - add more optimized XTS mode for x86-64
crypto: x86/camellia-aesni-avx - add more optimized XTS code
crypto: cast6-avx: use new optimized XTS code
crypto: x86/twofish-avx - use optimized XTS code
crypto: x86 - add more optimized XTS-mode for serpent-avx
xfrm: add rfc4494 AES-CMAC-96 support
crypto: add CMAC support to CryptoAPI
crypto: testmgr - add empty test vectors for null ciphers
crypto: testmgr - add AES GMAC test vectors
crypto: gcm - fix rfc4543 to handle async crypto correctly
crypto: gcm - make GMAC work when dst and src are different
hwrng: timeriomem - added devicetree hooks
...
- ARM big.LITTLE cpufreq driver from Viresh Kumar.
- exynos5440 cpufreq driver from Amit Daniel Kachhap.
- cpufreq core cleanup and code consolidation from Viresh Kumar and
Stratos Karafotis.
- cpufreq scalability improvement from Nathan Zimmer.
- AMD "frequency sensitivity feedback" powersave bias for the ondemand
cpufreq governor from Jacob Shin.
- cpuidle code consolidation and cleanups from Daniel Lezcano.
- ARM OMAP cpuidle fixes from Santosh Shilimkar and Daniel Lezcano.
- ACPICA fixes and other improvements from Bob Moore, Jung-uk Kim,
Lv Zheng, Yinghai Lu, Tang Chen, Colin Ian King, and Linn Crosetto.
- ACPI core updates related to hotplug from Toshi Kani, Paul Bolle,
Yasuaki Ishimatsu, and Rafael J. Wysocki.
- Intel Lynxpoint LPSS (Low-Power Subsystem) support improvements
from Rafael J. Wysocki and Andy Shevchenko.
/
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Merge tag 'pm+acpi-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI updates from Rafael J Wysocki:
- ARM big.LITTLE cpufreq driver from Viresh Kumar.
- exynos5440 cpufreq driver from Amit Daniel Kachhap.
- cpufreq core cleanup and code consolidation from Viresh Kumar and
Stratos Karafotis.
- cpufreq scalability improvement from Nathan Zimmer.
- AMD "frequency sensitivity feedback" powersave bias for the ondemand
cpufreq governor from Jacob Shin.
- cpuidle code consolidation and cleanups from Daniel Lezcano.
- ARM OMAP cpuidle fixes from Santosh Shilimkar and Daniel Lezcano.
- ACPICA fixes and other improvements from Bob Moore, Jung-uk Kim, Lv
Zheng, Yinghai Lu, Tang Chen, Colin Ian King, and Linn Crosetto.
- ACPI core updates related to hotplug from Toshi Kani, Paul Bolle,
Yasuaki Ishimatsu, and Rafael J Wysocki.
- Intel Lynxpoint LPSS (Low-Power Subsystem) support improvements from
Rafael J Wysocki and Andy Shevchenko.
* tag 'pm+acpi-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (192 commits)
cpufreq: Revert incorrect commit 5800043
cpufreq: MAINTAINERS: Add co-maintainer
cpuidle: add maintainer entry
ACPI / thermal: do not always return THERMAL_TREND_RAISING for active trip points
ARM: s3c64xx: cpuidle: use init/exit common routine
cpufreq: pxa2xx: initialize variables
ACPI: video: correct acpi_video_bus_add error processing
SH: cpuidle: use init/exit common routine
ARM: S5pv210: compiling issue, ARM_S5PV210_CPUFREQ needs CONFIG_CPU_FREQ_TABLE=y
ACPI: Fix wrong parameter passed to memblock_reserve
cpuidle: fix comment format
pnp: use %*phC to dump small buffers
isapnp: remove debug leftovers
ARM: imx: cpuidle: use init/exit common routine
ARM: davinci: cpuidle: use init/exit common routine
ARM: kirkwood: cpuidle: use init/exit common routine
ARM: calxeda: cpuidle: use init/exit common routine
ARM: tegra: cpuidle: use init/exit common routine for tegra3
ARM: tegra: cpuidle: use init/exit common routine for tegra2
ARM: OMAP4: cpuidle: use init/exit common routine
...
Pull core timer updates from Ingo Molnar:
"The main changes in this cycle's merge are:
- Implement shadow timekeeper to shorten in kernel reader side
blocking, by Thomas Gleixner.
- Posix timers enhancements by Pavel Emelyanov:
- allocate timer ID per process, so that exact timer ID allocations
can be re-created be checkpoint/restore code.
- debuggability and tooling (/proc/PID/timers, etc.) improvements.
- suspend/resume enhancements by Feng Tang: on certain new Intel Atom
processors (Penwell and Cloverview), there is a feature that the
TSC won't stop in S3 state, so the TSC value won't be reset to 0
after resume. This can be taken advantage of by the generic via
the CLOCK_SOURCE_SUSPEND_NONSTOP flag: instead of using the RTC to
recover/approximate sleep time, the main (and precise) clocksource
can be used.
- Fix /proc/timer_list for 4096 CPUs by Nathan Zimmer: on so many
CPUs the file goes beyond 4MB of size and thus the current
simplistic seqfile approach fails. Convert /proc/timer_list to a
proper seq_file with its own iterator.
- Cleanups and refactorings of the core timekeeping code by John
Stultz.
- International Atomic Clock time is managed by the NTP code
internally currently but not exposed externally. Separate the TAI
code out and add CLOCK_TAI support and TAI support to the hrtimer
and posix-timer code, by John Stultz.
- Add deep idle support enhacement to the broadcast clockevents core
timer code, by Daniel Lezcano: add an opt-in CLOCK_EVT_FEAT_DYNIRQ
clockevents feature (which will be utilized by future clockevents
driver updates), which allows the use of IRQ affinities to avoid
spurious wakeups of idle CPUs - the right CPU with an expiring
timer will be woken.
- Add new ARM bcm281xx clocksource driver, by Christian Daudt
- ... various other fixes and cleanups"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
clockevents: Set dummy handler on CPU_DEAD shutdown
timekeeping: Update tk->cycle_last in resume
posix-timers: Remove unused variable
clockevents: Switch into oneshot mode even if broadcast registered late
timer_list: Convert timer list to be a proper seq_file
timer_list: Split timer_list_show_tickdevices
posix-timers: Show sigevent info in proc file
posix-timers: Introduce /proc/PID/timers file
posix timers: Allocate timer id per process (v2)
timekeeping: Make sure to notify hrtimers when TAI offset changes
hrtimer: Fix ktime_add_ns() overflow on 32bit architectures
hrtimer: Add expiry time overflow check in hrtimer_interrupt
timekeeping: Shorten seq_count region
timekeeping: Implement a shadow timekeeper
timekeeping: Delay update of clock->cycle_last
timekeeping: Store cycle_last value in timekeeper struct as well
ntp: Remove ntp_lock, using the timekeeping locks to protect ntp state
timekeeping: Simplify tai updating from do_adjtimex
timekeeping: Hold timekeepering locks in do_adjtimex and hardpps
timekeeping: Move ADJ_SETOFFSET to top level do_adjtimex()
...
Patch adds AVX2/x86-64 implementation of Blowfish cipher, requiring 32 parallel
blocks for input (256 bytes). Table look-ups are performed using vpgatherdd
instruction directly from vector registers and thus should be faster than
earlier implementations.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add support for AMD Family 15h [and above] northbridge
performance counters. MSRs 0xc0010240 ~ 0xc0010247 are shared
across all cores that share a common northbridge.
Add support for AMD Family 16h L2 performance counters. MSRs
0xc0010230 ~ 0xc0010237 are shared across all cores that share a
common L2 cache.
We do not enable counter overflow interrupts. Sampling mode and
per-thread events are not supported.
Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Stephane Eranian <eranian@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20130419213428.GA8229@jshin-Toonie
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Future AMD processors, starting with Family 16h, can provide software
with feedback on how the workload may respond to frequency change --
memory-bound workloads will not benefit from higher frequency, where
as compute-bound workloads will. This patch enables this "frequency
sensitivity feedback" to aid the ondemand governor to make better
frequency change decisions by hooking into the powersave bias.
Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Acked-by: Thomas Renninger <trenn@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Convert AMD erratum 400 to the bug infrastructure. Then, retract all
exports for modules since they're not needed now and make the AMD
erratum checking machinery local to amd.c. Use forward declarations to
avoid shuffling too much code around needlessly.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-7-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Convert the AMD erratum 383 testing code to the bug infrastructure. This
allows keeping the AMD-specific erratum testing machinery private to
amd.c and not export symbols to modules needlessly.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-6-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
We add another 32-bit vector at the end of the ->x86_capability
bitvector which collects bugs present in CPUs. After all, a CPU bug is a
kind of a capability, albeit a strange one.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-2-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
On some new Intel Atom processors (Penwell and Cloverview), there is
a feature that the TSC won't stop in S3 state, say the TSC value
won't be reset to 0 after resume. This feature makes TSC a more reliable
clocksource and could benefit the timekeeping code during system
suspend/resume cycle, so add a flag for it.
Signed-off-by: Feng Tang <feng.tang@intel.com>
[jstultz: Fix checkpatch warning]
Signed-off-by: John Stultz <john.stultz@linaro.org>
On AMD family 15h processors, there are 4 new performance
counters (in addition to 6 core performance counters) that can
be used for counting northbridge events (i.e. DRAM accesses).
Their bit fields are almost identical to the core performance
counters. However, unlike the core performance counters, these
MSRs are shared between multiple cores (that share the same
northbridge).
We will reuse the same code path as existing family 10h
northbridge event constraints handler logic to enforce
this sharing.
Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Acked-by: Stephane Eranian <eranian@google.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jacob Shin <jacob.shin@amd.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1360171589-6381-7-git-send-email-jacob.shin@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull KVM updates from Marcelo Tosatti:
"Considerable KVM/PPC work, x86 kvmclock vsyscall support,
IA32_TSC_ADJUST MSR emulation, amongst others."
Fix up trivial conflict in kernel/sched/core.c due to cross-cpu
migration notifier added next to rq migration call-back.
* tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (156 commits)
KVM: emulator: fix real mode segment checks in address linearization
VMX: remove unneeded enable_unrestricted_guest check
KVM: VMX: fix DPL during entry to protected mode
x86/kexec: crash_vmclear_local_vmcss needs __rcu
kvm: Fix irqfd resampler list walk
KVM: VMX: provide the vmclear function and a bitmap to support VMCLEAR in kdump
x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary
KVM: MMU: optimize for set_spte
KVM: PPC: booke: Get/set guest EPCR register using ONE_REG interface
KVM: PPC: bookehv: Add EPCR support in mtspr/mfspr emulation
KVM: PPC: bookehv: Add guest computation mode for irq delivery
KVM: PPC: Make EPCR a valid field for booke64 and bookehv
KVM: PPC: booke: Extend MAS2 EPN mask for 64-bit
KVM: PPC: e500: Mask MAS2 EPN high 32-bits in 32/64 tlbwe emulation
KVM: PPC: Mask ea's high 32-bits in 32/64 instr emulation
KVM: PPC: e500: Add emulation helper for getting instruction ea
KVM: PPC: bookehv64: Add support for interrupt handling
KVM: PPC: bookehv: Remove GET_VCPU macro from exception handler
KVM: PPC: booke: Fix get_tb() compile error on 64-bit
KVM: PPC: e500: Silence bogus GCC warning in tlb code
...
Pull "Nuke 386-DX/SX support" from Ingo Molnar:
"This tree removes ancient-386-CPUs support and thus zaps quite a bit
of complexity:
24 files changed, 56 insertions(+), 425 deletions(-)
... which complexity has plagued us with extra work whenever we wanted
to change SMP primitives, for years.
Unfortunately there's a nostalgic cost: your old original 386 DX33
system from early 1991 won't be able to boot modern Linux kernels
anymore. Sniff."
I'm not sentimental. Good riddance.
* 'x86-nuke386-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, 386 removal: Document Nx586 as a 386 and thus unsupported
x86, cleanups: Simplify sync_core() in the case of no CPUID
x86, 386 removal: Remove CONFIG_X86_POPAD_OK
x86, 386 removal: Remove CONFIG_X86_WP_WORKS_OK
x86, 386 removal: Remove CONFIG_INVLPG
x86, 386 removal: Remove CONFIG_BSWAP
x86, 386 removal: Remove CONFIG_XADD
x86, 386 removal: Remove CONFIG_CMPXCHG
x86, 386 removal: Remove CONFIG_M386 from Kconfig
CPUID.7.0.EBX[1]=1 indicates IA32_TSC_ADJUST MSR 0x3b is supported
Basic design is to emulate the MSR by allowing reads and writes to a guest
vcpu specific location to store the value of the emulated MSR while adding
the value to the vmcs tsc_offset. In this way the IA32_TSC_ADJUST value will
be included in all reads to the TSC MSR whether through rdmsr or rdtsc. This
is of course as long as the "use TSC counter offsetting" VM-execution control
is enabled as well as the IA32_TSC_ADJUST control.
However, because hardware will only return the TSC + IA32_TSC_ADJUST +
vmsc tsc_offset for a guest process when it does and rdtsc (with the correct
settings) the value of our virtualized IA32_TSC_ADJUST must be stored in one
of these three locations. The argument against storing it in the actual MSR
is performance. This is likely to be seldom used while the save/restore is
required on every transition. IA32_TSC_ADJUST was created as a way to solve
some issues with writing TSC itself so that is not an option either.
The remaining option, defined above as our solution has the problem of
returning incorrect vmcs tsc_offset values (unless we intercept and fix, not
done here) as mentioned above. However, more problematic is that storing the
data in vmcs tsc_offset will have a different semantic effect on the system
than does using the actual MSR. This is illustrated in the following example:
The hypervisor set the IA32_TSC_ADJUST, then the guest sets it and a guest
process performs a rdtsc. In this case the guest process will get
TSC + IA32_TSC_ADJUST_hyperviser + vmsc tsc_offset including
IA32_TSC_ADJUST_guest. While the total system semantics changed the semantics
as seen by the guest do not and hence this will not cause a problem.
Signed-off-by: Will Auld <will.auld@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Introduce cpu_has_topoext to check for AMD's CPUID topology extensions
support. It indicates support for
CPUID Fn8000_001D_EAX_x[N:0]-CPUID Fn8000_001E_EDX
See AMD's CPUID Specification, Publication # 25481
(as of Rev. 2.34 September 2010)
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/r/20121019085813.GD26718@alberich
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
