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22,795 commits

Author SHA1 Message Date
Andy Lutomirski
29ea1b258b x86/entry/64: Migrate 64-bit and compat syscalls to the new exit handlers and remove old assembly code
These need to be migrated together, as the compat case used to
jump into the middle of the 64-bit exit code.

Remove the old assembly code.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/d4d1d70de08ac3640badf50048a9e8f18fe2497f.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:59:07 +02:00
Andy Lutomirski
cb6f64ed5a x86/entry/64: Really create an error-entry-from-usermode code path
In 539f511365 ("x86/asm/entry/64: Disentangle error_entry/exit
gsbase/ebx/usermode code"), I arranged the code slightly wrong
-- IRET faults would skip the code path that was intended to
execute on all error entries from user mode.  Fix it up.

While we're at it, make all the labels in error_entry local.

This does not fix a bug, but we'll need it, and it slightly
shrinks the code.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/91e17891e49fa3d61357eadc451529ad48143ee1.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:59:07 +02:00
Andy Lutomirski
c5c46f59e4 x86/entry: Add new, comprehensible entry and exit handlers written in C
The current x86 entry and exit code, written in a mixture of assembly and
C code, is incomprehensible due to being open-coded in a lot of places
without coherent documentation.

It appears to work primary by luck and duct tape: i.e. obvious runtime
failures were fixed on-demand, without re-thinking the design.

Due to those reasons our confidence level in that code is low, and it is
very difficult to incrementally improve.

Add new code written in C, in preparation for simply deleting the old
entry code.

prepare_exit_to_usermode() is a new function that will handle all
slow path exits to user mode.  It is called with IRQs disabled
and it leaves us in a state in which it is safe to immediately
return to user mode.  IRQs must not be re-enabled at any point
after prepare_exit_to_usermode() returns and user mode is actually
entered. (We can, of course, fail to enter user mode and treat
that failure as a fresh entry to kernel mode.)

All callers of do_notify_resume() will be migrated to call
prepare_exit_to_usermode() instead; prepare_exit_to_usermode() needs
to do everything that do_notify_resume() does today, but it also
takes care of scheduling and context tracking.  Unlike
do_notify_resume(), it does not need to be called in a loop.

syscall_return_slowpath() is exactly what it sounds like: it will
be called on any syscall exit slow path. It will replace
syscall_trace_leave() and it calls prepare_exit_to_usermode() on the
way out.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/c57c8b87661a4152801d7d3786eac2d1a2f209dd.1435952415.git.luto@kernel.org
[ Improved the changelog a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:59:06 +02:00
Andy Lutomirski
feed36cde0 x86/entry: Add enter_from_user_mode() and use it in syscalls
Changing the x86 context tracking hooks is dangerous because
there are no good checks that we track our context correctly.
Add a helper to check that we're actually in CONTEXT_USER when
we enter from user mode and wire it up for syscall entries.

Subsequent patches will wire this up for all non-NMI entries as
well.  NMIs are their own special beast and cannot currently
switch overall context tracking state.  Instead, they have their
own special RCU hooks.

This is a tiny speedup if !CONFIG_CONTEXT_TRACKING (removes a
branch) and a tiny slowdown if CONFIG_CONTEXT_TRACING (adds a
layer of indirection).  Eventually, we should fix up the core
context tracking code to supply a function that does what we
want (and can be much simpler than user_exit), which will enable
us to get rid of the extra call.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/853b42420066ec3fb856779cdc223a6dcb5d355b.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:59:06 +02:00
Andy Lutomirski
02fdcd5eac x86/traps, context_tracking: Assert that we're in CONTEXT_KERNEL in exception entries
Other than the super-atomic exception entries, all exception
entries are supposed to switch our context tracking state to
CONTEXT_KERNEL. Assert that they do.  These assertions appear
trivial at this point, as exception_enter() is the function
responsible for switching context, but I'm planning on reworking
x86's exception context tracking, and these assertions will help
make sure that all of this code keeps working.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20fa1ee2d943233a184aaf96ff75394d3b34dfba.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:59:05 +02:00
Andy Lutomirski
1f484aa690 x86/entry: Move C entry and exit code to arch/x86/entry/common.c
The entry and exit C helpers were confusingly scattered between
ptrace.c and signal.c, even though they aren't specific to
ptrace or signal handling.  Move them together in a new file.

This change just moves code around.  It doesn't change anything.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/324d686821266544d8572423cc281f961da445f4.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:59:05 +02:00
Andy Lutomirski
5e99cb7c35 x86/entry/64/compat: Fix bad fast syscall arg failure path
If user code does SYSCALL32 or SYSENTER without a valid stack,
then our attempt to determine the syscall args will result in a
failed uaccess fault.  Previously, we would try to recover by
jumping to the syscall exit code, but we'd run the syscall exit
work even though we never made it to the syscall entry work.

Clean it up by treating the failure path as a non-syscall entry
and exit pair.

This fixes strace's output when running the syscall_arg_fault
test. Without this fix, strace would get out of sync and would
fail to associate syscall entries with syscall exits.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/903010762c07a3d67df914fea2da84b52b0f8f1d.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:58:30 +02:00
Kees Cook
79063a7c02 x86/boot: Add hex output for debugging
This is useful for reporting various addresses or other values
while debugging early boot, for example, the recent kernel image
size vs kernel run size. For example, when
CONFIG_X86_VERBOSE_BOOTUP is set, this is now visible at boot
time:

	early console in setup code
	early console in decompress_kernel
	input_data: 0x0000000001e1526e
	input_len: 0x0000000000732236
	output: 0x0000000001000000
	output_len: 0x0000000001535640
	run_size: 0x00000000021fb000
	KASLR using RDTSC...

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Joe Perches <joe@perches.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/20150706230620.GA17501@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 08:59:05 +02:00
Andy Shevchenko
91780c41a9 x86/platform/intel/pmc_atom: Move the PMC-Atom code to arch/x86/platform/atom
This is specific driver for Intel Atom SoCs like BayTrail and
Braswell. Let's move it to dedicated folder and alleviate a
arch/x86/kernel burden.

There is no functional change.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Kumar P Mahesh <mahesh.kumar.p@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1436192944-56496-6-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 18:39:38 +02:00
Andy Shevchenko
2b8f8eddaf x86/platform/intel/pmc_atom: Add Cherrytrail PMC interface
The patch adds CHT PMC interface. This exposes all the South IP
device power states and S0ix states for CHT. The bit map of
FUNC_DIS and D3_STS_0 registers for SoCs are consistent. The
D3_STS_1 and FUNC_DIS_2 registers, however, are not aligned.
This is fixed by splitting a common mapping on per register basis.

(Originally based on code from Kumar P Mahesh.)

Originally-from: Kumar P Mahesh <mahesh.kumar.p@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1436192944-56496-5-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 18:39:38 +02:00
Andy Shevchenko
940406d1cf x86/platform/intel/pmc_atom: Supply register mappings via PMC object
The patch converts the functions to use the register mappings
provided by PMC object. It would help in case of mappings on
different platforms.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1436192944-56496-4-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 17:42:46 +02:00
Andy Shevchenko
c3c65aa6d4 x86/platform/intel/pmc_atom: Print index of device in loop
The register mapping may change from one platform to another.
Thus, indices might be not the same on different platforms. The
patch makes the code to print the device index dynamically at
run time.

The patch also changes the for loop to iterate over the map
until a terminator is found.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1436192944-56496-3-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 17:42:46 +02:00
Andy Shevchenko
68872eb9b1 x86/platform/intel/pmc_atom: Export accessors to PMC registers
Export the pmc_atom_read() and pmc_atom_write() accessors to the PMC
registers. On early initcall stages the functions will return
-ENODEV, and caller has to wait when it will be available.

Additionally make absence of debugfs a non-fatal error.

The patch will be useful for the upcoming fixes regarding to the
LPSS block found on Intel BayTrail-T and Braswell.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Kumar P Mahesh <mahesh.kumar.p@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1436192944-56496-2-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 17:42:45 +02:00
Steven Rostedt
827a82ff39 x86/earlyprintk: Allow early_printk() to use console style parameters like '115200n8'
When I enable early_printk on a kernel, I cut and paste the
console= input and add to earlyprintk parameter. But I notice
recently that ktest has not been detecting triple faults. The
way it detects it, is by seeing the kernel banner "Linux version
.." with a different kernel version pop up. Then I noticed that
early printk was no longer working on my console, which was why
ktest was not seeing it.

I bisected it down and it was added to 4.0 with this commit:

  ea9e9d8029 ("Specify PCI based UART for earlyprintk")

because it converted the simple_strtoul() that converts the baud
number into a kstrtoul(). The problem with this is, I had as my
baud rate, 115200n8 (acceptable for console=ttyS0), but because
of the "n8", the kstrtoul() doesn't parse the baud rate and
returns an error, which sets the baud rate to the default 9600.
This explains the garbage on my screen.

Now, earlyprintk= kernel parameter does not say it accepts that
format. Thus, one answer would simply be me changing my kernel
parameters to remove the "n8" since it isn't parsed anyway. But
I wonder if other people run into this, and it seems strange
that the two consoles for serial accepts different input.

I could also extend this to have earlyprintk do something with
that "n8" or whatever it has and have it match the console
parsing (which, BTW, still uses simple_strtoul(), as I guess it
has to).

This patch just makes my old kernel parameter parsing work like
it use to.

Although, simple_strtoull() is considered obsolete, it is the
only standard string parsing function that parses a number that
is attached to text. Ironically, commit ea9e9d8029 also added
several calls to simple_strtoul()!

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Cohen <david.a.cohen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stuart R. Anderson <stuart.r.anderson@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20150706101434.5f6a351b@gandalf.local.home
[ Cleaned it up a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 17:33:47 +02:00
Brian Gerst
9b54050bfe x86/compat: Separate ia32 and x32 compat ABIs
The x32 ABI is now independent of the ia32 compat ABI.  Common
code is now conditional on CONFIG_COMPAT, but unshared code like
syscall entry, signal handling, and the VDSO are under separate
config options.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-13-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:58 +02:00
Brian Gerst
0c3619ea67 x86/compat: Clean up HAVE_UID16 config
Merge the 32-bit compat config setting for HAVE_UID16 with the
32-bit native one.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-12-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:58 +02:00
Brian Gerst
3bead553ab x86/compat: Define ARCH_WANT_OLD_COMPAT_IPC only for 32-bit compat
x32 does not need CONFIG_ARCH_WANT_OLD_COMPAT_IPC=y.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-11-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:57 +02:00
Brian Gerst
5e2aad2460 x86/compat: Remove unneeded #include
Including sys_ia32.h is not needed in signal.c.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-10-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:57 +02:00
Brian Gerst
10ed34935e x86/compat, x86/perf: Don't build perf_callchain_user32() on x32
perf_callchain_user32() is not needed for x32.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-9-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:57 +02:00
Brian Gerst
c338867d0e x86/compat: Check for both 32-bit compat and x32 in get_gate_vma()
Change this to CONFIG_COMPAT so both 32-bit compat and x32 will
do the check.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-8-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:57 +02:00
Brian Gerst
ab8b82ee6d x86/compat: Don't build the 32-bit VDSO if not needed
Build the 32-bit vdso only for native 32-bit or 32-bit compat is
enabled.  x32 should not force it to build.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-7-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:56 +02:00
Brian Gerst
601275c3e0 x86/compat: Factor out ia32 compat code from compat_arch_ptrace()
Move the ia32-specific code in compat_arch_ptrace() into its
own function.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-6-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:56 +02:00
Brian Gerst
7da770785f x86/compat: Rename 'start_thread_ia32' to 'compat_start_thread'
This function is shared between the 32-bit compat and x32 ABIs.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-5-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:56 +02:00
Brian Gerst
b829d1be20 x86/compat: Move ucontext_x32 to sigframe.h
ia32.h should only contain the code for 32-bit compatability.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-4-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:55 +02:00
Brian Gerst
b2e02b820d x86/compat: Make mmap_is_ia32() common compat
TIF_ADDR32 is set for both ia32 and x32 tasks, so change from
CONFIG_IA32_EMULATION to CONFIG_COMPAT.  Use config_enabled()
to make the function more readable.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-3-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:55 +02:00
Brian Gerst
c0bfd26e13 x86/compat: Move copy_siginfo_*_user32() to signal_compat.c
copy_siginfo_to_user32() and copy_siginfo_from_user32() are used
by both the 32-bit compat and x32 ABIs.  Move them to
signal_compat.c.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/1434974121-32575-2-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:55 +02:00
George Spelvin
5a33fcb8d9 x86/asm/tsc: Save an instruction in DECLARE_ARGS users
Before, the code to do RDTSC looked like:

  rdtsc
  shl $0x20, %rdx
  mov %eax, %eax
  or  %rdx, %rax

The "mov %eax, %eax" is required to clear the high 32 bits of RAX.

By declaring low and high as 64-bit variables, the code is
simplified to:

  rdtsc
  shl $0x20,%rdx
  or  %rdx,%rax

Yes, it's a 2-byte instruction that's not on a critical path,
but there are principles to be upheld.

Every user of EAX_EDX_RET has been checked. I tried to check
users of EAX_EDX_ARGS, but there weren't any, so I deleted it to
be safe.

( There's no benefit to making "high" 64 bits, but it was the
  simplest way to proceed. )

Signed-off-by: George Spelvin <linux@horizon.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jacob.jun.pan@linux.intel.com
Link: http://lkml.kernel.org/r/20150618075906.4615.qmail@ns.horizon.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:30 +02:00
Andy Lutomirski
bb8dd96032 x86/asm/tsc: Remove rdtsc_barrier()
All callers have been converted to rdtsc_ordered().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/9baa4ae9a1e7c7c282f9cb2f15bb6bf5c2004032.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:30 +02:00
Andy Lutomirski
502dfeff23 x86/asm/tsc, x86/kvm: Drop open-coded barrier and use rdtsc_ordered() in kvmclock
__pvclock_read_cycles() used to have two barriers, one of which was unnecessary,
which got removed after an initial version of this patch was sent.

But the barrier is still open-coded unnecessarily - get rid of
that barrier and clean up the code by just using rdtsc_ordered().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/678981cc4761fb38a793c217c9cac42503cf3719.1434501121.git.luto@kernel.org
[ Ported it to v4.2-rc1. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:30 +02:00
Andy Lutomirski
27c634054a x86/asm/tsc: Use rdtsc_ordered() in read_tsc() instead of get_cycles()
There are two logical changes here.  First, this removes a check
for cpu_has_tsc.  That check is unnecessary, as we don't
register the TSC as a clocksource on systems that have no TSC.

Second, it adds a barrier, thus preventing observable
non-monotonicity.

I suspect that the missing barrier was never a problem in
practice because system calls themselves were heavy enough
barriers to prevent user code from observing time warps due to
speculation. (Without the corresponding barrier in the vDSO,
however, non-monotonicity is easy to detect.)

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/c6ff621a053127a65b70f175443578db7a0711be.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:29 +02:00
Andy Lutomirski
eee6946e44 x86/asm/tsc/sync: Use rdtsc_ordered() in check_tsc_warp() and drop extra barriers
Using get_cycles was unnecessary: check_tsc_warp() is not called
on TSC-less systems. Replace rdtsc_barrier(); get_cycles() with
rdtsc_ordered().

While we're at it, make the somewhat more dangerous change of
removing barrier_before_rdtsc after RDTSC in the TSC warp check
code. This should be okay, though -- the vDSO TSC code doesn't
have that barrier, so, if removing the barrier from the warp
check would cause us to detect a warp that we otherwise wouldn't
detect, then we have a genuine bug.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/387c4c3a75f875bcde6cd68cee013273a744f364.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:29 +02:00
Andy Lutomirski
03b9730b76 x86/asm/tsc: Add rdtsc_ordered() and use it in trivial call sites
rdtsc_barrier(); rdtsc() is an unnecessary mouthful and requires
more thought than should be necessary. Add an rdtsc_ordered()
helper and replace the trivial call sites with it.

This should not change generated code. The duplication of the
fence asm is temporary.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/dddbf98a2af53312e9aa73a5a2b1622fe5d6f52b.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:29 +02:00
Andy Lutomirski
4ea1636b04 x86/asm/tsc: Rename native_read_tsc() to rdtsc()
Now that there is no paravirt TSC, the "native" is
inappropriate. The function does RDTSC, so give it the obvious
name: rdtsc().

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/fd43e16281991f096c1e4d21574d9e1402c62d39.1434501121.git.luto@kernel.org
[ Ported it to v4.2-rc1. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:28 +02:00
Andy Lutomirski
fe47ae6e1a x86/asm/tsc: Remove rdtscl()
It has no more callers, and it was never a very sensible
interface to begin with. Users of the TSC should either read all
64 bits or explicitly throw out the high bits.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/250105f7cee519be9d7fc4464b5784caafc8f4fe.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:28 +02:00
Andy Lutomirski
3796366614 x86/asm/tsc, x86/cpu/amd: Use the full 64-bit TSC to detect the 2.6.2 bug
This code is timing 100k indirect calls, so the added overhead
of counting the number of cycles elapsed as a 64-bit number
should be insignificant.  Drop the optimization of using a
32-bit count.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/d58f339a9c0dd8352b50d2f7a216f67ec2844f20.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:27 +02:00
Andy Lutomirski
9cfa1a0279 x86/asm/tsc: Use the full 64-bit TSC in delay_tsc()
As a very minor optimization, delay_tsc() was only using the low
32 bits of the TSC. It's a delay function, so just use the whole
thing.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/bd1a277c71321b67c4794970cb5ace05efe21ab6.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:27 +02:00
Andy Lutomirski
ec69de52c6 x86/asm/tsc: Remove the rdtscp() and rdtscpll() macros
They have no users. Leave native_read_tscp() which seems
potentially useful despite also having no callers.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/6abfa3ef80534b5d73898a48c4d25e069303cbe5.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:26 +02:00
Andy Lutomirski
87be28aaf1 x86/asm/tsc: Replace rdtscll() with native_read_tsc()
Now that the ->read_tsc() paravirt hook is gone, rdtscll() is
just a wrapper around native_read_tsc(). Unwrap it.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/d2449ae62c1b1fb90195bcfb19ef4a35883a04dc.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:26 +02:00
Andy Lutomirski
9261e050b6 x86/asm/tsc, x86/paravirt: Remove read_tsc() and read_tscp() paravirt hooks
We've had ->read_tsc() and ->read_tscp() paravirt hooks since
the very beginning of paravirt, i.e.,

  d3561b7fa0 ("[PATCH] paravirt: header and stubs for paravirtualisation").

AFAICT, the only paravirt guest implementation that ever
replaced these calls was vmware, and it's gone. Arguably even
vmware shouldn't have hooked RDTSC -- we fully support systems
that don't have a TSC at all, so there's no point for a paravirt
implementation to pretend that we have a TSC but to replace it.

I also doubt that these hooks actually worked. Calls to rdtscl()
and rdtscll(), which respected the hooks, were used seemingly
interchangeably with native_read_tsc(), which did not.

Just remove them. If anyone ever needs them again, they can try
to make a case for why they need them.

Before, on a paravirt config:
  text    	data     bss     dec     hex filename
  12618257      1816384 1093632 15528273 ecf151 vmlinux

After:
  text		data     bss     dec     hex filename
  12617207      1816384 1093632 15527223 eced37 vmlinux

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Cc: virtualization@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/d08a2600fb298af163681e5efd8e599d889a5b97.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:26 +02:00
Andy Lutomirski
881d7bf843 x86/asm/tsc, kvm: Remove vget_cycles()
The only caller was KVM's read_tsc(). The only difference
between vget_cycles() and native_read_tsc() was that
vget_cycles() returned zero instead of crashing on TSC-less
systems. KVM already checks vclock_mode() before calling that
function, so the extra check is unnecessary. Also, KVM
(host-side) requires the TSC to exist.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/20615df14ae2eb713ea7a5f5123c1dc4c7ca993d.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:25 +02:00
Andy Lutomirski
c6e5ca35c4 x86/asm/tsc: Inline native_read_tsc() and remove __native_read_tsc()
In the following commit:

  cdc7957d19 ("x86: move native_read_tsc() offline")

... native_read_tsc() was moved out of line, presumably for some
now-obsolete vDSO-related reason. Undo it.

The entire rdtsc, shl, or sequence is only 11 bytes, and calls
via rdtscl() and similar helpers were already inlined.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/d05ffe2aaf8468ca475ebc00efad7b2fa174af19.1434501121.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:23:25 +02:00
Zhu Guihua
20d5e4a9cd x86/espfix: Init espfix on the boot CPU side
As we alloc pages with GFP_KERNEL in init_espfix_ap() which is
called before we enable local irqs, so the lockdep sub-system
would (correctly) trigger a warning about the potentially
blocking API.

So we allocate them on the boot CPU side when the secondary CPU is
brought up by the boot CPU, and hand them over to the secondary
CPU.

And we use alloc_pages_node() with the secondary CPU's node, to
make sure the espfix stack is NUMA-local to the CPU that is
going to use it.

Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Cc: <bp@alien8.de>
Cc: <luto@amacapital.net>
Cc: <luto@kernel.org>
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/c97add2670e9abebb90095369f0cfc172373ac94.1435824469.git.zhugh.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:00:34 +02:00
Zhu Guihua
1db875631f x86/espfix: Add 'cpu' parameter to init_espfix_ap()
Add a CPU index parameter to init_espfix_ap(), so that the
parameter could be propagated to the function for espfix
page allocation.

Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Cc: <bp@alien8.de>
Cc: <luto@amacapital.net>
Cc: <luto@kernel.org>
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/cde3fcf1b3211f3f03feb1a995bce3fee850f0fc.1435824469.git.zhugh.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:00:33 +02:00
Denys Vlasenko
c73e36b775 x86/asm/entry/32: Replace RESTORE_RSI_RDI with open-coded 32-bit reads
This doesn't change much, but uses shorter 32-bit insns:

        -48 8b 74 24 68         mov    0x68(%rsp),%rsi
        -48 8b 7c 24 70         mov    0x70(%rsp),%rdi
        -48 8b 54 24 60         mov    0x60(%rsp),%rdx
        +8b 54 24 60            mov    0x60(%rsp),%edx
        +8b 74 24 68            mov    0x68(%rsp),%esi
        +8b 7c 24 70            mov    0x70(%rsp),%edi

and does the loads in pt_regs order.

Since these are the only uses of RESTORE_RSI_RDI[_RDX], drop
these macros.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1435954742-2545-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 14:56:50 +02:00
Andrey Ryabinin
d6f2d75a7a x86/kasan: Move KASAN_SHADOW_OFFSET to the arch Kconfig
KASAN_SHADOW_OFFSET is purely arch specific setting,
so it should be in arch's Kconfig file.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1435828178-10975-7-git-send-email-a.ryabinin@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 14:53:15 +02:00
Andrey Ryabinin
8515522949 x86/kasan: Add message about KASAN being initialized
Print informational message to tell user that kernel
runs with KASAN enabled.

Add a "kasan: " prefix to all messages in kasan_init_64.c.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
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/1435828178-10975-6-git-send-email-a.ryabinin@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 14:53:14 +02:00
Andrey Ryabinin
d4f86beacc x86/kasan: Fix boot crash on AMD processors
While populating zero shadow wrong bits in upper level page
tables used. __PAGE_KERNEL_RO that was used for pgd/pud/pmd has
_PAGE_BIT_GLOBAL set. Global bit is present only in the lowest
level of the page translation hierarchy (ptes), and it should be
zero in upper levels.

This bug seems doesn't cause any troubles on Intel cpus, while
on AMDs it cause kernel crash on boot.

Use _KERNPG_TABLE bits for pgds/puds/pmds to fix this.

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: <stable@vger.kernel.org> # 4.0+
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
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/1435828178-10975-5-git-send-email-a.ryabinin@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 14:53:14 +02:00
Andrey Ryabinin
241d2c54c6 x86/kasan: Flush TLBs after switching CR3
load_cr3() doesn't cause tlb_flush if PGE enabled.

This may cause tons of false positive reports spamming the
kernel to death.

To fix this __flush_tlb_all() should be called explicitly
after CR3 changed.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: <stable@vger.kernel.org> # 4.0+
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
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/1435828178-10975-4-git-send-email-a.ryabinin@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 14:53:14 +02:00
Alexander Popov
5d5aa3cfca x86/kasan: Fix KASAN shadow region page tables
Currently KASAN shadow region page tables created without
respect of physical offset (phys_base). This causes kernel halt
when phys_base is not zero.

So let's initialize KASAN shadow region page tables in
kasan_early_init() using __pa_nodebug() which considers
phys_base.

This patch also separates x86_64_start_kernel() from KASAN low
level details by moving kasan_map_early_shadow(init_level4_pgt)
into kasan_early_init().

Remove the comment before clear_bss() which stopped bringing
much profit to the code readability. Otherwise describing all
the new order dependencies would be too verbose.

Signed-off-by: Alexander Popov <alpopov@ptsecurity.com>
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: <stable@vger.kernel.org> # 4.0+
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
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/1435828178-10975-3-git-send-email-a.ryabinin@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 14:53:13 +02:00
Andrey Ryabinin
d0f77d4d04 x86/init: Clear 'init_level4_pgt' earlier
Currently x86_64_start_kernel() has two KASAN related
function calls. The first call maps shadow to early_level4_pgt,
the second maps shadow to init_level4_pgt.

If we move clear_page(init_level4_pgt) earlier, we could hide
KASAN low level detail from generic x86_64 initialization code.
The next patch will do it.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: <stable@vger.kernel.org> # 4.0+
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
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/1435828178-10975-2-git-send-email-a.ryabinin@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 14:53:13 +02:00