Pull x86/xsave changes from Peter Anvin:
"This is a patchset to support the XSAVES instruction required to
support context switch of supervisor-only features in upcoming
silicon.
This patchset missed the 3.16 merge window, which is why it is based
on 3.15-rc7"
* 'x86-xsave-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, xsave: Add forgotten inline annotation
x86/xsaves: Clean up code in xstate offsets computation in xsave area
x86/xsave: Make it clear that the XSAVE macros use (%edi)/(%rdi)
Define kernel API to get address of each state in xsave area
x86/xsaves: Enable xsaves/xrstors
x86/xsaves: Call booting time xsaves and xrstors in setup_init_fpu_buf
x86/xsaves: Save xstate to task's xsave area in __save_fpu during booting time
x86/xsaves: Add xsaves and xrstors support for booting time
x86/xsaves: Clear reserved bits in xsave header
x86/xsaves: Use xsave/xrstor for saving and restoring user space context
x86/xsaves: Use xsaves/xrstors for context switch
x86/xsaves: Use xsaves/xrstors to save and restore xsave area
x86/xsaves: Define a macro for handling xsave/xrstor instruction fault
x86/xsaves: Define macros for xsave instructions
x86/xsaves: Change compacted format xsave area header
x86/alternative: Add alternative_input_2 to support alternative with two features and input
x86/xsaves: Add a kernel parameter noxsaves to disable xsaves/xrstors
Pull x86 mm changes from Ingo Molnar:
"The main change in this cycle is the rework of the TLB range flushing
code, to simplify, fix and consolidate the code. By Dave Hansen"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Set TLB flush tunable to sane value (33)
x86/mm: New tunable for single vs full TLB flush
x86/mm: Add tracepoints for TLB flushes
x86/mm: Unify remote INVLPG code
x86/mm: Fix missed global TLB flush stat
x86/mm: Rip out complicated, out-of-date, buggy TLB flushing
x86/mm: Clean up the TLB flushing code
x86/smep: Be more informative when signalling an SMEP fault
I think the flush_tlb_mm_range() code that tries to tune the
flush sizes based on the CPU needs to get ripped out for
several reasons:
1. It is obviously buggy. It uses mm->total_vm to judge the
task's footprint in the TLB. It should certainly be using
some measure of RSS, *NOT* ->total_vm since only resident
memory can populate the TLB.
2. Haswell, and several other CPUs are missing from the
intel_tlb_flushall_shift_set() function. Thus, it has been
demonstrated to bitrot quickly in practice.
3. It is plain wrong in my vm:
[ 0.037444] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0
[ 0.037444] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0
[ 0.037444] tlb_flushall_shift: 6
Which leads to it to never use invlpg.
4. The assumptions about TLB refill costs are wrong:
http://lkml.kernel.org/r/1337782555-8088-3-git-send-email-alex.shi@intel.com
(more on this in later patches)
5. I can not reproduce the original data: https://lkml.org/lkml/2012/5/17/59
I believe the sample times were too short. Running the
benchmark in a loop yields times that vary quite a bit.
Note that this leaves us with a static ceiling of 1 page. This
is a conservative, dumb setting, and will be revised in a later
patch.
This also removes the code which attempts to predict whether we
are flushing data or instructions. We expect instruction flushes
to be relatively rare and not worth tuning for explicitly.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140731154055.ABC88E89@viggo.jf.intel.com
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull more perf updates from Ingo Molnar:
"A second round of perf updates:
- wide reaching kprobes sanitization and robustization, with the hope
of fixing all 'probe this function crashes the kernel' bugs, by
Masami Hiramatsu.
- uprobes updates from Oleg Nesterov: tmpfs support, corner case
fixes and robustization work.
- perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo
et al:
* Add support to accumulate hist periods (Namhyung Kim)
* various fixes, refactorings and enhancements"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
perf: Differentiate exec() and non-exec() comm events
perf: Fix perf_event_comm() vs. exec() assumption
uprobes/x86: Rename arch_uprobe->def to ->defparam, minor comment updates
perf/documentation: Add description for conditional branch filter
perf/x86: Add conditional branch filtering support
perf/tool: Add conditional branch filter 'cond' to perf record
perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND'
uprobes: Teach copy_insn() to support tmpfs
uprobes: Shift ->readpage check from __copy_insn() to uprobe_register()
perf/x86: Use common PMU interrupt disabled code
perf/ARM: Use common PMU interrupt disabled code
perf: Disable sampled events if no PMU interrupt
perf: Fix use after free in perf_remove_from_context()
perf tools: Fix 'make help' message error
perf record: Fix poll return value propagation
perf tools: Move elide bool into perf_hpp_fmt struct
perf tools: Remove elide setup for SORT_MODE__MEMORY mode
perf tools: Fix "==" into "=" in ui_browser__warning assignment
perf tools: Allow overriding sysfs and proc finding with env var
perf tools: Consider header files outside perf directory in tags target
...
This patch adds a kernel parameter noxsaves to disable xsaves/xrstors feature.
The kernel will fall back to use xsaveopt and xrstor to save and restor
xstates. By using this parameter, xsave area occupies more memory because
standard form of xsave area in xsaveopt/xrstor occupies more memory than
compacted form of xsave area.
This patch adds a description of the kernel parameter noxsaveopt in doc.
The code to support the parameter noxsaveopt has been in the kernel before.
This patch just adds the description of this parameter in the doc.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1401387164-43416-4-git-send-email-fenghua.yu@intel.com
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>
This code is used during CPU setup, and it isn't strictly speaking
related to the 32-bit vdso. It's easier to understand how this
works when the code is closer to its callers.
This also lets syscall32_cpu_init be static, which might save some
trivial amount of kernel text.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/4e466987204e232d7b55a53ff6b9739f12237461.1399317206.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Prohibit probing on debug_stack_reset and debug_stack_set_zero.
Since the both functions are called from TRACE_IRQS_ON/OFF_DEBUG
macros which run in int3 ist entry, probing it may cause a soft
lockup.
This happens when the kernel built with CONFIG_DYNAMIC_FTRACE=y
and CONFIG_TRACE_IRQFLAGS=y.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/20140417081712.26341.32994.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 threadinfo changes from Ingo Molnar:
"The main change here is the consolidation/unification of 32 and 64 bit
thread_info handling methods, from Steve Rostedt"
* 'x86-threadinfo-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, threadinfo: Redo "x86: Use inline assembler to get sp"
x86: Clean up dumpstack_64.c code
x86: Keep thread_info on thread stack in x86_32
x86: Prepare removal of previous_esp from i386 thread_info structure
x86: Nuke GET_THREAD_INFO_WITH_ESP() macro for i386
x86: Nuke the supervisor_stack field in i386 thread_info
x86_64 uses a per_cpu variable kernel_stack to always point to
the thread stack of current. This is where the thread_info is stored
and is accessed from this location even when the irq or exception stack
is in use. This removes the complexity of having to maintain the
thread info on the stack when interrupts are running and having to
copy the preempt_count and other fields to the interrupt stack.
x86_32 uses the old method of copying the thread_info from the thread
stack to the exception stack just before executing the exception.
Having the two different requires #ifdefs and also the x86_32 way
is a bit of a pain to maintain. By converting x86_32 to the same
method of x86_64, we can remove #ifdefs, clean up the x86_32 code
a little, and remove the overhead of the copy.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20110806012354.263834829@goodmis.org
Link: http://lkml.kernel.org/r/20140206144321.852942014@goodmis.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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
If SMAP support is not compiled into the kernel, don't enable SMAP in
CR4 -- in fact, we should clear it, because the kernel doesn't contain
the proper STAC/CLAC instructions for SMAP support.
Found by Fengguang Wu's test system.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Link: http://lkml.kernel.org/r/20140213124550.GA30497@localhost
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> # v3.7+
Pull x86 cpu changes from Ingo Molnar:
"The biggest change that stands out is the increase of the
CONFIG_NR_CPUS range from 4096 to 8192 - as real hardware out there
already went beyond 4k CPUs ...
We only allow more than 512 CPUs if offstack cpumasks are enabled.
CONFIG_MAXSMP=y remains to be the 'you are nuts!' extreme testcase,
which now means a max of 8192 CPUs"
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Increase max CPU count to 8192
x86/cpu: Allow higher NR_CPUS values
x86/cpu: Always print SMP information in /proc/cpuinfo
x86/cpu: Track legacy CPU model data only on 32-bit kernels
struct cpu_dev's c_models is only ever set inside CONFIG_X86_32
conditionals (or code that's being built for 32-bit only), so
there's no use of reserving the (empty) space for the model
names in a 64-bit kernel.
Similarly, c_size_cache is only used in the #else of a
CONFIG_X86_64 conditional, so reserving space for (and in one
case even initializing) that field is pointless for 64-bit
kernels too.
While moving both fields to the end of the structure, I also
noticed that:
- the c_models array size was one too small, potentially causing
table_lookup_model() to return garbage on Intel CPUs (intel.c's
instance was lacking the sentinel with family being zero), so the
patch bumps that by one,
- c_models' vendor sub-field was unused (and anyway redundant
with the base structure's c_x86_vendor field), so the patch deletes it.
Also rename the legacy fields so that their legacy nature stands out
and comment their declarations.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/5265036802000078000FC4DB@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Convert x86 to use a per-cpu preemption count. The reason for doing so
is that accessing per-cpu variables is a lot cheaper than accessing
thread_info variables.
We still need to save/restore the actual preemption count due to
PREEMPT_ACTIVE so we place the per-cpu __preempt_count variable in the
same cache-line as the other hot __switch_to() variables such as
current_task.
NOTE: this save/restore is required even for !PREEMPT kernels as
cond_resched() also relies on preempt_count's PREEMPT_ACTIVE to ignore
task_struct::state.
Also rename thread_info::preempt_count to ensure nobody is
'accidentally' still poking at it.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-gzn5rfsf8trgjoqx8hyayy3q@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings. In any case, they are temporary and harmless.
This removes all the arch/x86 uses of the __cpuinit macros from
all C files. x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.
[1] https://lkml.org/lkml/2013/5/20/589
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: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Pull x86 tracing updates from Ingo Molnar:
"This tree adds IRQ vector tracepoints that are named after the handler
and which output the vector #, based on a zero-overhead approach that
relies on changing the IDT entries, by Seiji Aguchi.
The new tracepoints look like this:
# perf list | grep -i irq_vector
irq_vectors:local_timer_entry [Tracepoint event]
irq_vectors:local_timer_exit [Tracepoint event]
irq_vectors:reschedule_entry [Tracepoint event]
irq_vectors:reschedule_exit [Tracepoint event]
irq_vectors:spurious_apic_entry [Tracepoint event]
irq_vectors:spurious_apic_exit [Tracepoint event]
irq_vectors:error_apic_entry [Tracepoint event]
irq_vectors:error_apic_exit [Tracepoint event]
[...]"
* 'x86-tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tracing: Add config option checking to the definitions of mce handlers
trace,x86: Do not call local_irq_save() in load_current_idt()
trace,x86: Move creation of irq tracepoints from apic.c to irq.c
x86, trace: Add irq vector tracepoints
x86: Rename variables for debugging
x86, trace: Introduce entering/exiting_irq()
tracing: Add DEFINE_EVENT_FN() macro
[Purpose of this patch]
As Vaibhav explained in the thread below, tracepoints for irq vectors
are useful.
http://www.spinics.net/lists/mm-commits/msg85707.html
<snip>
The current interrupt traces from irq_handler_entry and irq_handler_exit
provide when an interrupt is handled. They provide good data about when
the system has switched to kernel space and how it affects the currently
running processes.
There are some IRQ vectors which trigger the system into kernel space,
which are not handled in generic IRQ handlers. Tracing such events gives
us the information about IRQ interaction with other system events.
The trace also tells where the system is spending its time. We want to
know which cores are handling interrupts and how they are affecting other
processes in the system. Also, the trace provides information about when
the cores are idle and which interrupts are changing that state.
<snip>
On the other hand, my usecase is tracing just local timer event and
getting a value of instruction pointer.
I suggested to add an argument local timer event to get instruction pointer before.
But there is another way to get it with external module like systemtap.
So, I don't need to add any argument to irq vector tracepoints now.
[Patch Description]
Vaibhav's patch shared a trace point ,irq_vector_entry/irq_vector_exit, in all events.
But there is an above use case to trace specific irq_vector rather than tracing all events.
In this case, we are concerned about overhead due to unwanted events.
So, add following tracepoints instead of introducing irq_vector_entry/exit.
so that we can enable them independently.
- local_timer_vector
- reschedule_vector
- call_function_vector
- call_function_single_vector
- irq_work_entry_vector
- error_apic_vector
- thermal_apic_vector
- threshold_apic_vector
- spurious_apic_vector
- x86_platform_ipi_vector
Also, introduce a logic switching IDT at enabling/disabling time so that a time penalty
makes a zero when tracepoints are disabled. Detailed explanations are as follows.
- Create trace irq handlers with entering_irq()/exiting_irq().
- Create a new IDT, trace_idt_table, at boot time by adding a logic to
_set_gate(). It is just a copy of original idt table.
- Register the new handlers for tracpoints to the new IDT by introducing
macros to alloc_intr_gate() called at registering time of irq_vector handlers.
- Add checking, whether irq vector tracing is on/off, into load_current_idt().
This has to be done below debug checking for these reasons.
- Switching to debug IDT may be kicked while tracing is enabled.
- On the other hands, switching to trace IDT is kicked only when debugging
is disabled.
In addition, the new IDT is created only when CONFIG_TRACING is enabled to avoid being
used for other purposes.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C323ED.5050708@hds.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Rename variables for debugging to describe meaning of them precisely.
Also, introduce a generic way to switch IDT by checking a current state,
debug on/off.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C323A8.7050905@hds.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
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>
Reimplement FPU detection code in C and drop old, not-so-recommended
detection method in asm. Move all the relevant stuff into i387.c where
it conceptually belongs. Finally drop cpuinfo_x86.hard_math.
[ hpa: huge thanks to Borislav for taking my original concept patch
and productizing it ]
[ Boris, note to self: do not use static_cpu_has before alternatives! ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1367244262-29511-2-git-send-email-bp@alien8.de
Link: http://lkml.kernel.org/r/1365436666-9837-2-git-send-email-bp@alien8.de
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.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>
In 64 bit, load ucode on AP in cpu_init().
In 32 bit, show ucode loading info on AP in cpu_init(). Microcode has been
loaded earlier before paging. Now it is safe to show the loading microcode
info on this AP.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1356075872-3054-5-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Remove static declaration in have_cpuid_p() to make it a global function. The
function will be called in early loading microcode.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1356075872-3054-4-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull big execve/kernel_thread/fork unification series from Al Viro:
"All architectures are converted to new model. Quite a bit of that
stuff is actually shared with architecture trees; in such cases it's
literally shared branch pulled by both, not a cherry-pick.
A lot of ugliness and black magic is gone (-3KLoC total in this one):
- kernel_thread()/kernel_execve()/sys_execve() redesign.
We don't do syscalls from kernel anymore for either kernel_thread()
or kernel_execve():
kernel_thread() is essentially clone(2) with callback run before we
return to userland, the callbacks either never return or do
successful do_execve() before returning.
kernel_execve() is a wrapper for do_execve() - it doesn't need to
do transition to user mode anymore.
As a result kernel_thread() and kernel_execve() are
arch-independent now - they live in kernel/fork.c and fs/exec.c
resp. sys_execve() is also in fs/exec.c and it's completely
architecture-independent.
- daemonize() is gone, along with its parts in fs/*.c
- struct pt_regs * is no longer passed to do_fork/copy_process/
copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.
- sys_fork()/sys_vfork()/sys_clone() unified; some architectures
still need wrappers (ones with callee-saved registers not saved in
pt_regs on syscall entry), but the main part of those suckers is in
kernel/fork.c now."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
do_coredump(): get rid of pt_regs argument
print_fatal_signal(): get rid of pt_regs argument
ptrace_signal(): get rid of unused arguments
get rid of ptrace_signal_deliver() arguments
new helper: signal_pt_regs()
unify default ptrace_signal_deliver
flagday: kill pt_regs argument of do_fork()
death to idle_regs()
don't pass regs to copy_process()
flagday: don't pass regs to copy_thread()
bfin: switch to generic vfork, get rid of pointless wrappers
xtensa: switch to generic clone()
openrisc: switch to use of generic fork and clone
unicore32: switch to generic clone(2)
score: switch to generic fork/vfork/clone
c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
mn10300: switch to generic fork/vfork/clone
h8300: switch to generic fork/vfork/clone
tile: switch to generic clone()
...
Conflicts:
arch/microblaze/include/asm/Kbuild
Previously these functions were not run on the BSP (CPU 0, the boot processor)
since the boot processor init would only be executed before this functionality
was initialized.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1352835171-3958-11-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull x86/smap support from Ingo Molnar:
"This adds support for the SMAP (Supervisor Mode Access Prevention) CPU
feature on Intel CPUs: a hardware feature that prevents unintended
user-space data access from kernel privileged code.
It's turned on automatically when possible.
This, in combination with SMEP, makes it even harder to exploit kernel
bugs such as NULL pointer dereferences."
Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added
includes right next to each other.
* 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, smep, smap: Make the switching functions one-way
x86, suspend: On wakeup always initialize cr4 and EFER
x86-32: Start out eflags and cr4 clean
x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space
x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry
x86, smap: Reduce the SMAP overhead for signal handling
x86, smap: A page fault due to SMAP is an oops
x86, smap: Turn on Supervisor Mode Access Prevention
x86, smap: Add STAC and CLAC instructions to control user space access
x86, uaccess: Merge prototypes for clear_user/__clear_user
x86, smap: Add a header file with macros for STAC/CLAC
x86, alternative: Add header guards to <asm/alternative-asm.h>
x86, alternative: Use .pushsection/.popsection
x86, smap: Add CR4 bit for SMAP
x86-32, mm: The WP test should be done on a kernel page
Pull x86/mm changes from Ingo Molnar:
"The biggest change is new TLB partial flushing code for AMD CPUs.
(The v3.6 kernel had the Intel CPU side code, see commits
e0ba94f14f74..effee4b9b3b.)
There's also various other refinements around the TLB flush code"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Distinguish TLB shootdown interrupts from other functions call interrupts
x86/mm: Fix range check in tlbflush debugfs interface
x86, cpu: Preset default tlb_flushall_shift on AMD
x86, cpu: Add AMD TLB size detection
x86, cpu: Push TLB detection CPUID check down
x86, cpu: Fixup tlb_flushall_shift formatting
Pull x86/fpu update from Ingo Molnar:
"The biggest change is the addition of the non-lazy (eager) FPU saving
support model and enabling it on CPUs with optimized xsaveopt/xrstor
FPU state saving instructions.
There are also various Sparse fixes"
Fix up trivial add-add conflict in arch/x86/kernel/traps.c
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, kvm: fix kvm's usage of kernel_fpu_begin/end()
x86, fpu: remove cpu_has_xmm check in the fx_finit()
x86, fpu: make eagerfpu= boot param tri-state
x86, fpu: enable eagerfpu by default for xsaveopt
x86, fpu: decouple non-lazy/eager fpu restore from xsave
x86, fpu: use non-lazy fpu restore for processors supporting xsave
lguest, x86: handle guest TS bit for lazy/non-lazy fpu host models
x86, fpu: always use kernel_fpu_begin/end() for in-kernel FPU usage
x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu()
x86, fpu: remove unnecessary user_fpu_end() in save_xstate_sig()
x86, fpu: drop_fpu() before restoring new state from sigframe
x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels
x86, fpu: Consolidate inline asm routines for saving/restoring fpu state
x86, signal: Cleanup ifdefs and is_ia32, is_x32
Pull x86 debug update from Ingo Molnar:
"Various small enhancements"
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/debug: Dump family, model, stepping of the boot CPU
x86/iommu: Use NULL instead of plain 0 for __IOMMU_INIT
x86/iommu: Drop duplicate const in __IOMMU_INIT
x86/fpu/xsave: Keep __user annotation in casts
x86/pci/probe_roms: Add missing __iomem annotation to pci_map_biosrom()
x86/signals: ia32_signal.c: add __user casts to fix sparse warnings
x86/vdso: Add __user annotation to VDSO32_SYMBOL
x86: Fix __user annotations in asm/sys_ia32.h
There is no fundamental reason why we should switch SMEP and SMAP on
during early cpu initialization just to switch them off again. Now
with %eflags and %cr4 forced to be initialized to a clean state, we
only need the one-way enable. Also, make the functions inline to make
them (somewhat) harder to abuse.
This does mean that SMEP and SMAP do not get initialized anywhere near
as early. Even using early_param() instead of __setup() doesn't give
us control early enough to do this during the early cpu initialization
phase. This seems reasonable to me, because SMEP and SMAP should not
matter until we have userspace to protect ourselves from, but it does
potentially make it possible for a bug involving a "leak of
permissions to userspace" to get uncaught.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Reason for merge:
x86/fpu changed the structure of some of the code that x86/smap
changes; mostly fpu-internal.h but also minor changes to the
signal code.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Resolved Conflicts:
arch/x86/ia32/ia32_signal.c
arch/x86/include/asm/fpu-internal.h
arch/x86/kernel/signal.c
When Supervisor Mode Access Prevention (SMAP) is enabled, access to
userspace from the kernel is controlled by the AC flag. To make the
performance of manipulating that flag acceptable, there are two new
instructions, STAC and CLAC, to set and clear it.
This patch adds those instructions, via alternative(), when the SMAP
feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the
SYSCALL entry mask; there is simply no reason to make that one
conditional.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
When acting on a user bug report, we find ourselves constantly
asking for /proc/cpuinfo in order to know the exact family,
model, stepping of the CPU in question.
Instead of having to ask this, add this to dmesg so that it is
visible and no ambiguities can ensue from looking at the
official name string of the CPU coming from CPUID and trying
to map it to f/m/s.
Output then looks like this:
[ 0.146041] smpboot: CPU0: AMD FX(tm)-8100 Eight-Core Processor (fam: 15, model: 01, stepping: 02)
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/r/1347640666-13638-1-git-send-email-bp@amd64.org
[ tweaked it minimally to add commas. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Decouple non-lazy/eager fpu restore policy from the existence of the xsave
feature. Introduce a synthetic CPUID flag to represent the eagerfpu
policy. "eagerfpu=on" boot paramter will enable the policy.
Requested-by: H. Peter Anvin <hpa@zytor.com>
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1347300665-6209-2-git-send-email-suresh.b.siddha@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
On 64 bit x86 we save the current eflags in cpu_init for use in
ret_from_fork. Strictly speaking reserved bits in EFLAGS should
be read as written but in practise it is unlikely that EFLAGS
could ever be extended in this way and the kernel alread clears
any undefined flags early on.
The equivalent 32 bit code simply hard codes 0x0202 as the new
EFLAGS.
This change makes 64 bit use the same mechanism to setup the
initial EFLAGS on fork. Note that 64 bit resets EFLAGS before
calling schedule_tail() as opposed to 32 bit which calls
schedule_tail() first. Therefore the correct value for EFLAGS
has opposite IF bit.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/20120824195847.GA31628@moon
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Clear AVX, AVX2 features along with clearing XSAVE feature bits,
as part of the parsing "noxsave" parameter.
Fixes the kernel boot panic with "noxsave" boot parameter.
We could have checked cpu_has_osxsave along with cpu_has_avx etc, but Peter
mentioned clearing the feature bits will be better for uses like
static_cpu_has() etc.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1343755754.2041.2.camel@sbsiddha-desk.sc.intel.com
Cc: <stable@vger.kernel.org> # v3.5
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Push the max CPUID leaf check into the ->detect_tlb function and remove
general test case from the generic path.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344272439-29080-3-git-send-email-bp@amd64.org
Acked-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The TLB characteristics appeared like this in dmesg:
[ 0.065817] Last level iTLB entries: 4KB 512, 2MB 1024, 4MB 512
[ 0.065817] Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 512
[ 0.065817] tlb_flushall_shift is 0xffffffff
where tlb_flushall_shift is actually -1 but dumped as a hex number.
However, the Kconfig option CONFIG_DEBUG_TLBFLUSH and the rest of the
code treats this as a signed decimal and states "If you set it to -1,
the code flushes the whole TLB unconditionally."
So, fix its formatting in accordance with the other references to it.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344272439-29080-2-git-send-email-bp@amd64.org
Acked-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Pull x86/mm changes from Peter Anvin:
"The big change here is the patchset by Alex Shi to use INVLPG to flush
only the affected pages when we only need to flush a small page range.
It also removes the special INVALIDATE_TLB_VECTOR interrupts (32
vectors!) and replace it with an ordinary IPI function call."
Fix up trivial conflicts in arch/x86/include/asm/apic.h (added code next
to changed line)
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tlb: Fix build warning and crash when building for !SMP
x86/tlb: do flush_tlb_kernel_range by 'invlpg'
x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR
x86/tlb: enable tlb flush range support for x86
mm/mmu_gather: enable tlb flush range in generic mmu_gather
x86/tlb: add tlb_flushall_shift knob into debugfs
x86/tlb: add tlb_flushall_shift for specific CPU
x86/tlb: fall back to flush all when meet a THP large page
x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range
x86/tlb_info: get last level TLB entry number of CPU
x86: Add read_mostly declaration/definition to variables from smp.h
x86: Define early read-mostly per-cpu macros
Testing show different CPU type(micro architectures and NUMA mode) has
different balance points between the TLB flush all and multiple invlpg.
And there also has cases the tlb flush change has no any help.
This patch give a interface to let x86 vendor developers have a chance
to set different shift for different CPU type.
like some machine in my hands, balance points is 16 entries on
Romely-EP; while it is at 8 entries on Bloomfield NHM-EP; and is 256 on
IVB mobile CPU. but on model 15 core2 Xeon using invlpg has nothing
help.
For untested machine, do a conservative optimization, same as NHM CPU.
Signed-off-by: Alex Shi <alex.shi@intel.com>
Link: http://lkml.kernel.org/r/1340845344-27557-5-git-send-email-alex.shi@intel.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
