Commit Graph

70 Commits

Author SHA1 Message Date
Eric W. Biederman
d12fe87e62 signal/testing: Don't look for __SI_FAULT in userspace
Fix the debug print statements in these tests where they reference
si_codes and in particular __SI_FAULT.  __SI_FAULT is a kernel
internal value and should never be seen by userspace.

While I am in there also fix si_code_str.  si_codes are an enumeration
there are not a bitmap so == and not & is the apropriate operation to
test for an si_code.

Cc: Dave Hansen <dave.hansen@linux.intel.com>
Fixes: 5f23f6d082 ("x86/pkeys: Add self-tests")
Fixes: e754aedc26 ("x86/mpx, selftests: Add MPX self test")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-07-19 19:13:15 -05:00
Linus Torvalds
2868b2513a linux-kselftest-4.12-rc1
This update consists of:
 
 -- important fixes for build failures and clean target related warnings
    to address regressions introduced in:
    88baa78d1f ("selftests: remove duplicated all and clean target")
 
 -- several minor spelling fixes in and log messages and comment blocks.
 
 -- Enabling configs for better test coverage in ftrace, vm, cpufreq tests.
 -- .gitignore changes
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Merge tag 'linux-kselftest-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kselftest updates from Shuah Khan:
 "This update consists of:

   - important fixes for build failures and clean target related
     warnings to address regressions introduced in commit 88baa78d1f
     ("selftests: remove duplicated all and clean target")

   - several minor spelling fixes in and log messages and comment
     blocks.

   - Enabling configs for better test coverage in ftrace, vm, and
     cpufreq tests.

   - .gitignore changes"

* tag 'linux-kselftest-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (26 commits)
  selftests: x86: add missing executables to .gitignore
  selftests: watchdog: accept multiple params on command line
  selftests: create cpufreq kconfig fragments
  selftests: x86: override clean in lib.mk to fix warnings
  selftests: sync: override clean in lib.mk to fix warnings
  selftests: splice: override clean in lib.mk to fix warnings
  selftests: gpio: fix clean target to remove all generated files and dirs
  selftests: add gpio generated files to .gitignore
  selftests: powerpc: override clean in lib.mk to fix warnings
  selftests: gpio: override clean in lib.mk to fix warnings
  selftests: futex: override clean in lib.mk to fix warnings
  selftests: lib.mk: define CLEAN macro to allow Makefiles to override clean
  selftests: splice: fix clean target to not remove default_file_splice_read.sh
  selftests: gpio: add config fragment for gpio-mockup
  selftests: breakpoints: allow to cross-compile for aarch64/arm64
  selftests/Makefile: Add missed PHONY targets
  selftests/vm/run_vmtests: Fix wrong comment
  selftests/Makefile: Add missed closing `"` in comment
  selftests/vm/run_vmtests: Polish output text
  selftests/timers: fix spelling mistake: "Asynchronous"
  ...
2017-05-08 20:43:30 -07:00
Shuah Khan
945f8f5f86 selftests: x86: add missing executables to .gitignore
Executables that are common for both x86_32 and x86_64 are missing
from .gitignore. Add them.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-05-03 10:55:20 -06:00
Shuah Khan
eebed11a3d selftests: x86: override clean in lib.mk to fix warnings
Add override with EXTRA_CLEAN for lib.mk clean to fix the following
warnings from clean target run.

Makefile:44: warning: overriding recipe for target 'clean'
../lib.mk:55: warning: ignoring old recipe for target 'clean'

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-04-27 08:05:23 -06:00
Joerg Roedel
5f2173e056 x86/mpx, selftests: Only check bounds-vs-shadow when we keep shadow
The check between the hardware state and our shadow of it is
checked in the signal handler for all bounds exceptions,
even for the ones where we don't keep the shadow up2date.
This is a problem because when no shadow is kept the handler
fails at this point and hides the real reason of the
exception.

Move the check into the code-path evaluating normal bounds
exceptions to prevent this.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kselftest@vger.kernel.org
Link: http://lkml.kernel.org/r/1491488598-27346-1-git-send-email-joro@8bytes.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-12 08:40:59 +02:00
Andy Lutomirski
65973dd3fd selftests/x86/ldt_gdt_32: Work around a glibc sigaction() bug
i386 glibc is buggy and calls the sigaction syscall incorrectly.

This is asymptomatic for normal programs, but it blows up on
programs that do evil things with segmentation.  The ldt_gdt
self-test is an example of such an evil program.

This doesn't appear to be a regression -- I think I just got lucky
with the uninitialized memory that glibc threw at the kernel when I
wrote the test.

This hackish fix manually issues sigaction(2) syscalls to undo the
damage.  Without the fix, ldt_gdt_32 segfaults; with the fix, it
passes for me.

See: https://sourceware.org/bugzilla/show_bug.cgi?id=21269

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/aaab0f9f93c9af25396f01232608c163a760a668.1490218061.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-23 08:25:07 +01:00
Linus Torvalds
ec3b93ae0b Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes and minor updates all over the place:

   - an SGI/UV fix
   - a defconfig update
   - a build warning fix
   - move the boot_params file to the arch location in debugfs
   - a pkeys fix
   - selftests fix
   - boot message fixes
   - sparse fixes
   - a resume warning fix
   - ioapic hotplug fixes
   - reboot quirks

  ... plus various minor cleanups"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/build/x86_64_defconfig: Enable CONFIG_R8169
  x86/reboot/quirks: Add ASUS EeeBook X205TA/W reboot quirk
  x86/hpet: Prevent might sleep splat on resume
  x86/boot: Correct setup_header.start_sys name
  x86/purgatory: Fix sparse warning, symbol not declared
  x86/purgatory: Make functions and variables static
  x86/events: Remove last remnants of old filenames
  x86/pkeys: Check against max pkey to avoid overflows
  x86/ioapic: Split IOAPIC hot-removal into two steps
  x86/PCI: Implement pcibios_release_device to release IRQ from IOAPIC
  x86/intel_rdt: Remove duplicate inclusion of linux/cpu.h
  x86/vmware: Remove duplicate inclusion of asm/timer.h
  x86/hyperv: Hide unused label
  x86/reboot/quirks: Add ASUS EeeBook X205TA reboot quirk
  x86/platform/uv/BAU: Fix HUB errors by remove initial write to sw-ack register
  x86/selftests: Add clobbers for int80 on x86_64
  x86/apic: Simplify enable_IR_x2apic(), remove try_to_enable_IR()
  x86/apic: Fix a warning message in logical CPU IDs allocation
  x86/kdebugfs: Move boot params hierarchy under (debugfs)/x86/
2017-03-07 14:47:24 -08:00
Linus Torvalds
2d62e0768d Second batch of KVM changes for 4.11 merge window
PPC:
  * correct assumption about ASDR on POWER9
  * fix MMIO emulation on POWER9
 
 x86:
  * add a simple test for ioperm
  * cleanup TSS
    (going through KVM tree as the whole undertaking was caused by VMX's
     use of TSS)
  * fix nVMX interrupt delivery
  * fix some performance counters in the guest
 
 And two cleanup patches.
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Merge tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull more KVM updates from Radim Krčmář:
 "Second batch of KVM changes for the 4.11 merge window:

  PPC:
   - correct assumption about ASDR on POWER9
   - fix MMIO emulation on POWER9

  x86:
   - add a simple test for ioperm
   - cleanup TSS (going through KVM tree as the whole undertaking was
     caused by VMX's use of TSS)
   - fix nVMX interrupt delivery
   - fix some performance counters in the guest

  ... and two cleanup patches"

* tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: nVMX: Fix pending events injection
  x86/kvm/vmx: remove unused variable in segment_base()
  selftests/x86: Add a basic selftest for ioperm
  x86/asm: Tidy up TSS limit code
  kvm: convert kvm.users_count from atomic_t to refcount_t
  KVM: x86: never specify a sample period for virtualized in_tx_cp counters
  KVM: PPC: Book3S HV: Don't use ASDR for real-mode HPT faults on POWER9
  KVM: PPC: Book3S HV: Fix software walk of guest process page tables
2017-03-04 11:36:19 -08:00
Andy Lutomirski
0eb1d0fa6a selftests/x86: Add a basic selftest for ioperm
This doesn't fully exercise the interaction between KVM and ioperm(),
but it does test basic functionality.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-01 17:03:23 +01:00
Dmitry Safonov
2a4d0c627f x86/selftests: Add clobbers for int80 on x86_64
Kernel erases R8..R11 registers prior returning to userspace
from int80:

  https://lkml.org/lkml/2009/10/1/164

GCC can reuse these registers and doesn't expect them to change
during syscall invocation. I met this kind of bug in CRIU once
GCC 6.1 and CLANG stored local variables in those registers
and the kernel zerofied them during syscall:

  990d33f1a1

By that reason I suggest to add those registers to clobbers
in selftests.  Also, as noted by Andy - removed unneeded clobber
for flags in INT $0x80 inline asm.

Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: 0x7f454c46@gmail.com
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kselftest@vger.kernel.org
Link: http://lkml.kernel.org/r/20170213101336.20486-1-dsafonov@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-01 10:24:56 +01:00
Linus Torvalds
c4f3f22edd linux-kselftest-4.11-rc1
This update consists of:
 
 -- fixes to several existing tests from Stafford Horne
 -- cpufreq tests from Viresh Kumar
 -- Selftest build and install fixes from Bamvor Jian Zhang
    and Michael Ellerman
 -- Fixes to protection-keys tests from Dave Hansen
 -- Warning fixes from Shuah Khan
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Merge tag 'linux-kselftest-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull Kselftest update from Shuah Khan:
 "This update consists of:

   - fixes to several existing tests from Stafford Horne

   - cpufreq tests from Viresh Kumar

   - Selftest build and install fixes from Bamvor Jian Zhang and Michael
     Ellerman

   - Fixes to protection-keys tests from Dave Hansen

   - Warning fixes from Shuah Khan"

* tag 'linux-kselftest-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (28 commits)
  selftests/powerpc: Fix remaining fallout from recent changes
  selftests/powerpc: Fix the clean rule since recent changes
  selftests: Fix the .S and .S -> .o rules
  selftests: Fix the .c linking rule
  selftests: Fix selftests build to just build, not run tests
  selftests, x86, protection_keys: fix wrong offset in siginfo
  selftests, x86, protection_keys: fix uninitialized variable warning
  selftest: cpufreq: Update MAINTAINERS file
  selftest: cpufreq: Add special tests
  selftest: cpufreq: Add support to test cpufreq modules
  selftest: cpufreq: Add suspend/resume/hibernate support
  selftest: cpufreq: Add support for cpufreq tests
  selftests: Add intel_pstate to TARGETS
  selftests/intel_pstate: Update makefile to match new style
  selftests/intel_pstate: Fix warning on loop index overflow
  cpupower: Restore format of frequency-info limit
  selftests/futex: Add headers to makefile dependencies
  selftests/futex: Add stdio used for logging
  selftests: x86 protection_keys remove dead code
  selftests: x86 protection_keys fix unused variable compile warnings
  ...
2017-02-25 15:32:53 -08:00
Linus Torvalds
8b5abde16b Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "A laundry list of changes: KASAN improvements/fixes for ptdump, a
  self-test fix, PAT cleanup and wbinvd() avoidance, removal of stale
  code and documentation updates"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/ptdump: Add address marker for KASAN shadow region
  x86/mm/ptdump: Optimize check for W+X mappings for CONFIG_KASAN=y
  x86/mm/pat: Use rb_entry()
  x86/mpx: Re-add MPX to selftests Makefile
  x86/mm: Remove CONFIG_DEBUG_NX_TEST
  x86/mm/cpa: Avoid wbinvd() for PREEMPT
  x86/mm: Improve documentation for low-level device I/O functions
2017-02-20 15:57:19 -08:00
Linus Torvalds
4abaa800fd Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm update from Ingo Molnar:
 "This adds a new SYSRET testcase"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  selftests/x86: Add a selftest for SYSRET to noncanonical addresses
2017-02-20 14:03:03 -08:00
Dave Hansen
2195bff041 selftests, x86, protection_keys: fix wrong offset in siginfo
The siginfo contains a bunch of information about the fault.
For protection keys, it tells us which protection key's
permissions were violated.

The wrong offset in here leads to reading garbage and thus
failures in the tests.

We should probably eventually move this over to using the
kernel's headers defining the siginfo instead of a hard-coded
offset.  But, for now, just do the simplest fix.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-02-08 11:15:43 -07:00
Dave Hansen
16846c2d96 selftests, x86, protection_keys: fix uninitialized variable warning
'orig_pkru' might have been uninitialized here.  Fix it.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-02-08 11:15:35 -07:00
Dave Hansen
e64d5fbe56 x86/mpx: Re-add MPX to selftests Makefile
Ingo pointed out that the MPX tests were no longer in the selftests
Makefile.  It appears that I shot myself in the foot on this one
and accidentally removed them when I added the pkeys tests, probably
from bungling a merge conflict.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 5f23f6d082 ("x86/pkeys: Add self-tests")
Link: http://lkml.kernel.org/r/20170201225629.C3070852@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-02 08:09:18 +01:00
Shuah Khan
3e91293ffc selftests: x86 protection_keys remove dead code
Remove commented out calls to pkey_get().

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-01-11 09:51:23 -07:00
Shuah Khan
fbb02ed8a1 selftests: x86 protection_keys fix unused variable compile warnings
Fix unused variable compile warnings in protection_keys.c

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-01-11 09:51:15 -07:00
bamvor.zhangjian@huawei.com
a8ba798bc8 selftests: enable O and KBUILD_OUTPUT
Enable O and KBUILD_OUTPUT for kselftest. User could compile kselftest
to another directory by passing O or KBUILD_OUTPUT. And O is high
priority than KBUILD_OUTPUT.

Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-01-05 13:42:22 -07:00
Colin King
7738789fba selftests: x86/pkeys: fix spelling mistake: "itertation" -> "iteration"
Fix spelling mistake in print test pass message.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2017-01-05 13:24:18 -07:00
Andy Lutomirski
6606021401 selftests/x86: Add a selftest for SYSRET to noncanonical addresses
SYSRET to a noncanonical address will blow up on Intel CPUs.  Linux
needs to prevent this from happening in two major cases, and the
criteria will become more complicated when support for larger virtual
address spaces is added.

A fast-path SYSCALL will fall through to the following instruction
using SYSRET without any particular checking.  To prevent fall-through
to a noncanonical address, Linux prevents the highest canonical page
from being mapped.  This test case checks a variety of possible maximum
addresses to make sure that either we can't map code there or that
SYSCALL fall-through works.

A slow-path system call can return anywhere.  Linux needs to make sure
that, if the return address is non-canonical, it won't use SYSRET.
This test cases causes sigreturn() to return to a variety of addresses
(with RCX == RIP) and makes sure that nothing explodes.

Some of this code comes from Kirill Shutemov.

Kirill reported the following output with 5-level paging enabled:

  [RUN]   sigreturn to 0x800000000000
  [OK]    Got SIGSEGV at RIP=0x800000000000
  [RUN]   sigreturn to 0x1000000000000
  [OK]    Got SIGSEGV at RIP=0x1000000000000
  [RUN]   sigreturn to 0x2000000000000
  [OK]    Got SIGSEGV at RIP=0x2000000000000
  [RUN]   sigreturn to 0x4000000000000
  [OK]    Got SIGSEGV at RIP=0x4000000000000
  [RUN]   sigreturn to 0x8000000000000
  [OK]    Got SIGSEGV at RIP=0x8000000000000
  [RUN]   sigreturn to 0x10000000000000
  [OK]    Got SIGSEGV at RIP=0x10000000000000
  [RUN]   sigreturn to 0x20000000000000
  [OK]    Got SIGSEGV at RIP=0x20000000000000
  [RUN]   sigreturn to 0x40000000000000
  [OK]    Got SIGSEGV at RIP=0x40000000000000
  [RUN]   sigreturn to 0x80000000000000
  [OK]    Got SIGSEGV at RIP=0x80000000000000
  [RUN]   sigreturn to 0x100000000000000
  [OK]    Got SIGSEGV at RIP=0x100000000000000
  [RUN]   sigreturn to 0x200000000000000
  [OK]    Got SIGSEGV at RIP=0x200000000000000
  [RUN]   sigreturn to 0x400000000000000
  [OK]    Got SIGSEGV at RIP=0x400000000000000
  [RUN]   sigreturn to 0x800000000000000
  [OK]    Got SIGSEGV at RIP=0x800000000000000
  [RUN]   sigreturn to 0x1000000000000000
  [OK]    Got SIGSEGV at RIP=0x1000000000000000
  [RUN]   sigreturn to 0x2000000000000000
  [OK]    Got SIGSEGV at RIP=0x2000000000000000
  [RUN]   sigreturn to 0x4000000000000000
  [OK]    Got SIGSEGV at RIP=0x4000000000000000
  [RUN]   sigreturn to 0x8000000000000000
  [OK]    Got SIGSEGV at RIP=0x8000000000000000
  [RUN]   Trying a SYSCALL that falls through to 0x7fffffffe000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x7ffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x800000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0xfffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x1000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x1fffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x2000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x3fffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x4000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x7fffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x8000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0xffffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x10000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x1ffffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x20000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x3ffffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x40000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x7ffffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x80000000000000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0xfffffffffff000
  [OK]    We survived
  [RUN]   Trying a SYSCALL that falls through to 0x100000000000000
  [OK]    mremap to 0xfffffffffff000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x1fffffffffff000
  [OK]    mremap to 0x1ffffffffffe000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x200000000000000
  [OK]    mremap to 0x1fffffffffff000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x3fffffffffff000
  [OK]    mremap to 0x3ffffffffffe000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x400000000000000
  [OK]    mremap to 0x3fffffffffff000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x7fffffffffff000
  [OK]    mremap to 0x7ffffffffffe000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x800000000000000
  [OK]    mremap to 0x7fffffffffff000 failed
  [RUN]   Trying a SYSCALL that falls through to 0xffffffffffff000
  [OK]    mremap to 0xfffffffffffe000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x1000000000000000
  [OK]    mremap to 0xffffffffffff000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x1ffffffffffff000
  [OK]    mremap to 0x1fffffffffffe000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x2000000000000000
  [OK]    mremap to 0x1ffffffffffff000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x3ffffffffffff000
  [OK]    mremap to 0x3fffffffffffe000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x4000000000000000
  [OK]    mremap to 0x3ffffffffffff000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x7ffffffffffff000
  [OK]    mremap to 0x7fffffffffffe000 failed
  [RUN]   Trying a SYSCALL that falls through to 0x8000000000000000
  [OK]    mremap to 0x7ffffffffffff000 failed

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e70bd9a3f90657ba47b755100a20475d038fa26b.1482808435.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-05 09:20:02 +01:00
Andy Lutomirski
3200ca8069 selftests/x86: Add test_vdso to test getcpu()
I'll eventually add tests for more vDSO functions here.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Megha <megha.dey@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/945cd29901a62a3cc6ea7d6ee5e389ab1ec1ac0c.1479320367.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-17 08:31:22 +01:00
Linus Torvalds
93c26d7dc0 Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull protection keys syscall interface from Thomas Gleixner:
 "This is the final step of Protection Keys support which adds the
  syscalls so user space can actually allocate keys and protect memory
  areas with them. Details and usage examples can be found in the
  documentation.

  The mm side of this has been acked by Mel"

* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pkeys: Update documentation
  x86/mm/pkeys: Do not skip PKRU register if debug registers are not used
  x86/pkeys: Fix pkeys build breakage for some non-x86 arches
  x86/pkeys: Add self-tests
  x86/pkeys: Allow configuration of init_pkru
  x86/pkeys: Default to a restrictive init PKRU
  pkeys: Add details of system call use to Documentation/
  generic syscalls: Wire up memory protection keys syscalls
  x86: Wire up protection keys system calls
  x86/pkeys: Allocation/free syscalls
  x86/pkeys: Make mprotect_key() mask off additional vm_flags
  mm: Implement new pkey_mprotect() system call
  x86/pkeys: Add fault handling for PF_PK page fault bit
2016-10-10 11:01:51 -07:00
Andy Lutomirski
1ef0199a1a selftests/x86/sigreturn: Use CX, not AX, as the scratch register
RAX is handled specially in ESPFIX64.  Use CX as our scratch
register so that, if something goes wrong with RAX handling, we'll
notice.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/9ceeb24ea56925586c330dc46306f757ddea9fb5.1473717910.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-13 20:34:15 +02:00
Dave Hansen
5f23f6d082 x86/pkeys: Add self-tests
This code should be a good demonstration of how to use the new
system calls as well as how to use protection keys in general.

This code shows how to:
1. Manipulate the Protection Keys Rights User (PKRU) register
2. Set a protection key on memory
3. Fetch and/or modify PKRU from the signal XSAVE state
4. Read the kernel-provided protection key in the siginfo
5. Set up an execute-only mapping

There are currently 13 tests:

  test_read_of_write_disabled_region
  test_read_of_access_disabled_region
  test_write_of_write_disabled_region
  test_write_of_access_disabled_region
  test_kernel_write_of_access_disabled_region
  test_kernel_write_of_write_disabled_region
  test_kernel_gup_of_access_disabled_region
  test_kernel_gup_write_to_write_disabled_region
  test_executing_on_unreadable_memory
  test_ptrace_of_child
  test_pkey_syscalls_on_non_allocated_pkey
  test_pkey_syscalls_bad_args
  test_pkey_alloc_exhaust

Each of the tests is run with plain memory (via mmap(MAP_ANON)),
transparent huge pages, and hugetlb.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-arch@vger.kernel.org
Cc: Dave Hansen <dave@sr71.net>
Cc: mgorman@techsingularity.net
Cc: arnd@arndb.de
Cc: linux-api@vger.kernel.org
Cc: shuahkh@osg.samsung.com
Cc: linux-mm@kvack.org
Cc: luto@kernel.org
Cc: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/20160729163024.FC5A0C2D@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-09 13:02:28 +02:00
Colin Ian King
1d723de739 selftests/x86: Fix spelling mistake "preseve" -> "preserve"
Trivial fix to spelling mistakes in printf messages.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kselftest@vger.kernel.org
Link: http://lkml.kernel.org/r/20160828105106.9763-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-08 08:50:35 +02:00
Ingo Molnar
38452af242 Merge branch 'x86/asm' into x86/mm, to resolve conflicts
Conflicts:
	tools/testing/selftests/x86/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:26:04 +02:00
Dmitry Safonov
f80fd3a5ff selftests/x86: Add vDSO mremap() test
Should print this on vDSO remapping success (on new kernels):

 [root@localhost ~]# ./test_mremap_vdso_32
	AT_SYSINFO_EHDR is 0xf773f000
 [NOTE]	Moving vDSO: [f773f000, f7740000] -> [a000000, a001000]
 [OK]

Or print that mremap() for vDSOs is unsupported:

 [root@localhost ~]# ./test_mremap_vdso_32
	AT_SYSINFO_EHDR is 0xf773c000
 [NOTE]	Moving vDSO: [0xf773c000, 0xf773d000] -> [0xf7737000, 0xf7738000]
 [FAIL]	mremap() of the vDSO does not work on this kernel!

Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: 0x7f454c46@gmail.com
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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kselftest@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20160628113539.13606-3-dsafonov@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08 14:17:51 +02:00
Dave Hansen
e754aedc26 x86/mpx, selftests: Add MPX self test
I've had this code for a while, but never submitted it upstream.  Now
that Skylake hardware is out in the wild, folks can actually run this
for real.  It tests the following:

	1. The MPX hardware is enabled by the kernel and doing what it
	   is supposed to
	2. The MPX management code is present and enabled in the kernel
	3. MPX Signal handling
	4. The MPX bounds table population code (on-demand population)
	5. The MPX bounds table unmapping code (kernel-initiated freeing
	   when unused)

This has also caught bugs in the XSAVE code because MPX state is
saved/restored with XSAVE.

I'm submitting it now because it would have caught the recent issues
with the compat_siginfo code not being properly augmented when new
siginfo state is added.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160608172535.5B40B0EE@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-14 12:19:24 +02:00
Andy Lutomirski
d63f4b5269 selftests/x86/ldt_gdt: Test set_thread_area() deletion of an active segment
Now that set_thread_area() is supposed to give deterministic behavior
when it modifies in-use segments, test it.

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: 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/f2bc11af1ee1a0f815ed910840cbdba06b640a20.1461698311.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 11:56:42 +02:00
Andy Lutomirski
0051202f6a selftests/x86: Test the FSBASE/GSBASE API and context switching
This catches two distinct bugs in the current code.  I'll fix them.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-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: Rudolf Marek <r.marek@assembler.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/7e5941148d1e2199f070dadcdf7355959f5f8e85.1460075211.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13 10:20:41 +02:00
Andy Lutomirski
b08983015c selftests/x86: Add an iopl test
This exercises two cases that are known to be buggy on Xen PV right
now.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.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/61afe904c95c92abb29cd075b51e10e7feb0f774.1458162709.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-17 09:49:26 +01:00
Andy Lutomirski
a318beea22 selftests/x86: In syscall_nt, test NT|TF as well
Setting TF prevents fastpath returns in most cases, which causes the
test to fail on 32-bit kernels because 32-bit kernels do not, in
fact, handle NT correctly on SYSENTER entries.

The next patch will fix 32-bit kernels.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/bd4bb48af6b10c0dc84aec6dbcf487ed25683495.1457578375.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-10 09:48:12 +01:00
Andy Lutomirski
4036134322 selftests/x86: Add a test for syscall restart under ptrace
This catches a regression from the compat syscall rework.  The
32-bit variant of this test currently fails.  The issue is that, for
a 32-bit tracer and a 32-bit tracee, GETREGS+SETREGS with no changes
should be a no-op.  It currently isn't a no-op if RAX indicates
signal restart, because the high bits get cleared and the kernel
loses track of the restart state.

Reported-by: Robert O'Callahan <robert@ocallahan.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/c4040b40b5b4a37ed31375a69b683f753ec6788a.1455142412.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 09:51:06 +01:00
Andy Lutomirski
adcfd23ead selftests/x86: Fix some error messages in ptrace_syscall
I had some obvious typos.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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: Robert O'Callahan <robert@ocallahan.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e5e6772d4802986cf7df702e646fa24ac14f2204.1455142412.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 09:51:06 +01:00
Andy Lutomirski
4f6c893822 selftests/x86: Add tests for UC_SIGCONTEXT_SS and UC_STRICT_RESTORE_SS
This tests the two ABI-preserving cases that DOSEMU cares about, and
it also explicitly tests the new UC_SIGCONTEXT_SS and
UC_STRICT_RESTORE_SS flags.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Stas Sergeev <stsp@list.ru>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f3d08f98541d0bd3030ceb35e05e21f59e30232c.1455664054.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 08:32:12 +01:00
Andy Lutomirski
6c25da5ad5 x86/signal/64: Re-add support for SS in the 64-bit signal context
This is a second attempt to make the improvements from c6f2062935
("x86/signal/64: Fix SS handling for signals delivered to 64-bit
programs"), which was reverted by 51adbfbba5c6 ("x86/signal/64: Add
support for SS in the 64-bit signal context").

This adds two new uc_flags flags.  UC_SIGCONTEXT_SS will be set for
all 64-bit signals (including x32).  It indicates that the saved SS
field is valid and that the kernel supports the new behavior.

The goal is to fix a problems with signal handling in 64-bit tasks:
SS wasn't saved in the 64-bit signal context, making it awkward to
determine what SS was at the time of signal delivery and making it
impossible to return to a non-flat SS (as calling sigreturn clobbers
SS).

This also made it extremely difficult for 64-bit tasks to return to
fully-defined 16-bit contexts, because only the kernel can easily do
espfix64, but sigreturn was unable to set a non-flag SS:ESP.
(DOSEMU has a monstrous hack to partially work around this
limitation.)

If we could go back in time, the correct fix would be to make 64-bit
signals work just like 32-bit signals with respect to SS: save it
in signal context, reset it when delivering a signal, and restore
it in sigreturn.

Unfortunately, doing that (as I tried originally) breaks DOSEMU:
DOSEMU wouldn't reset the signal context's SS when clearing the LDT
and changing the saved CS to 64-bit mode, since it predates the SS
context field existing in the first place.

This patch is a bit more complicated, and it tries to balance a
bunch of goals.  It makes most cases of changing ucontext->ss during
signal handling work as expected.

I do this by special-casing the interesting case.  On sigreturn,
ucontext->ss will be honored by default, unless the ucontext was
created from scratch by an old program and had a 64-bit CS
(unfortunately, CRIU can do this) or was the result of changing a
32-bit signal context to 64-bit without resetting SS (as DOSEMU
does).

For the benefit of new 64-bit software that uses segmentation (new
versions of DOSEMU might), the new behavior can be detected with a
new ucontext flag UC_SIGCONTEXT_SS.

To avoid compilation issues, __pad0 is left as an alias for ss in
ucontext.

The nitty-gritty details are documented in the header file.

This patch also re-enables the sigreturn_64 and ldt_gdt_64 selftests,
as the kernel change allows both of them to pass.

Tested-by: Stas Sergeev <stsp@list.ru>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/749149cbfc3e75cd7fcdad69a854b399d792cc6f.1455664054.git.luto@kernel.org
[ Small readability edit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 08:32:11 +01:00
Andy Lutomirski
e21d50f386 selftests/x86: Add check_initial_reg_state()
This checks that ELF binaries are started with an appropriately
blank register state.

( There's currently a nasty special case in the entry asm to
  arrange for this. I'm planning on removing the special case,
  and this will help make sure I don't break it. )

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: Frederic Weisbecker <fweisbec@gmail.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/ef54f8d066b30a3eb36bbf26300eebb242185700.1454022279.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-29 09:46:37 +01:00
Andy Lutomirski
c31b34255b selftests/x86: Extend Makefile to allow 64-bit-only tests
Previously the Makefile supported 32-bit-only tests and tests
that were 32-bit and 64-bit.  This adds the support for tests
that are only built as 64-bit binaries.

There aren't any yet, but there might be a few some day.

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: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkhan@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-api@vger.kernel.org
Link: http://lkml.kernel.org/r/99789bfe65706e6df32cc7e13f656e8c9fa92031.1454022279.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-29 09:46:36 +01:00
Andy Lutomirski
65cacec1ba selftests/x86: Test __kernel_sigreturn and __kernel_rt_sigreturn
The vdso-based sigreturn mechanism is fragile and isn't used by
modern glibc so, if we break it, we'll only notice when someone
tests an unusual libc.

Add an explicit selftest.

[ I wrote this while debugging a Bionic breakage -- my first guess
  was that I had somehow messed up sigreturn.  I've caused problems in
  that code before, and it's really easy to fail to notice it because
  there's nothing on a modern distro that needs vdso-based sigreturn. ]

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: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/32946d714156879cd8e5d8eab044cd07557ed558.1452628504.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-13 10:34:40 +01:00
Andy Lutomirski
0f672809f9 selftests/x86: Disable the ldt_gdt_64 test for now
ldt_gdt.c relies on cross-cpu invalidation of SS to do one of
its tests.  On 32-bit builds, this works fine, but on 64-bit
builds, it only works if the kernel has proper SS sigcontext
handling for 64-bit user programs.

Since the SS fixes are currently reverted, restrict the test
case to 32 bits for now.

In principle, I could change the test to use a different segment
register, but it would be messy: CS can't point to the LDT for
64-bit code, and the other registers don't result in immediate
faults because they aren't reloaded on kernel -> user
transitions.

When we fix sigcontext (in 4.6?), we can revert this.

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: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/231591d9122d282402d8f53175134f8db5b3bc73.1452561752.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-12 11:09:26 +01:00
Linus Torvalds
ce4d72fac1 Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fpu changes from Ingo Molnar:
 "There are two main areas of changes:

   - Rework of the extended FPU state code to robustify the kernel's
     usage of cpuid provided xstate sizes - and related changes (Dave
     Hansen)"

   - math emulation enhancements: new modern FPU instructions support,
     with testcases, plus cleanups (Denys Vlasnko)"

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/fpu: Fixup uninitialized feature_name warning
  x86/fpu/math-emu: Add support for FISTTP instructions
  x86/fpu/math-emu, selftests: Add test for FISTTP instructions
  x86/fpu/math-emu: Add support for FCMOVcc insns
  x86/fpu/math-emu: Add support for F[U]COMI[P] insns
  x86/fpu/math-emu: Remove define layer for undocumented opcodes
  x86/fpu/math-emu, selftests: Add tests for FCMOV and FCOMI insns
  x86/fpu/math-emu: Remove !NO_UNDOC_CODE
  x86/fpu: Check CPU-provided sizes against struct declarations
  x86/fpu: Check to ensure increasing-offset xstate offsets
  x86/fpu: Correct and check XSAVE xstate size calculations
  x86/fpu: Add C structures for AVX-512 state components
  x86/fpu: Rework YMM definition
  x86/fpu/mpx: Rework MPX 'xstate' types
  x86/fpu: Add xfeature_enabled() helper instead of test_bit()
  x86/fpu: Remove 'xfeature_nr'
  x86/fpu: Rework XSTATE_* macros to remove magic '2'
  x86/fpu: Rename XFEATURES_NR_MAX
  x86/fpu: Rename XSAVE macros
  x86/fpu: Remove partial LWP support definitions
  ...
2015-11-03 20:50:26 -08:00
Linus Torvalds
a75a3f6fc9 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm changes from Ingo Molnar:
 "The main change in this cycle is another step in the big x86 system
  call interface rework by Andy Lutomirski, which moves most of the low
  level x86 entry code from assembly to C, for all syscall entries
  except native 64-bit system calls:

    arch/x86/entry/entry_32.S        | 182 ++++------
    arch/x86/entry/entry_64_compat.S | 547 ++++++++-----------------------
    194 insertions(+), 535 deletions(-)

  ... our hope is that the final remaining step (converting native
  64-bit system calls) will be less painful as all the previous steps,
  given that most of the legacies and quirks are concentrated around
  native 32-bit and compat environments"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
  x86/entry/32: Fix FS and GS restore in opportunistic SYSEXIT
  x86/entry/32: Fix entry_INT80_32() to expect interrupts to be on
  um/x86: Fix build after x86 syscall changes
  x86/asm: Remove the xyz_cfi macros from dwarf2.h
  selftests/x86: Style fixes for the 'unwind_vdso' test
  x86/entry/64/compat: Document sysenter_fix_flags's reason for existence
  x86/entry: Split and inline syscall_return_slowpath()
  x86/entry: Split and inline prepare_exit_to_usermode()
  x86/entry: Use pt_regs_to_thread_info() in syscall entry tracing
  x86/entry: Hide two syscall entry assertions behind CONFIG_DEBUG_ENTRY
  x86/entry: Micro-optimize compat fast syscall arg fetch
  x86/entry: Force inlining of 32-bit syscall code
  x86/entry: Make irqs_disabled checks in exit code depend on lockdep
  x86/entry: Remove unnecessary IRQ twiddling in fast 32-bit syscalls
  x86/asm: Remove thread_info.sysenter_return
  x86/entry/32: Re-implement SYSENTER using the new C path
  x86/entry/32: Switch INT80 to the new C syscall path
  x86/entry/32: Open-code return tracking from fork and kthreads
  x86/entry/compat: Implement opportunistic SYSRETL for compat syscalls
  x86/vdso/compat: Wire up SYSENTER and SYSCSALL for compat userspace
  ...
2015-11-03 18:59:10 -08:00
Andy Lutomirski
226f1f729c selftests/x86: Add a fork() to entry_from_vm86 to catch fork bugs
Mere possession of vm86 state is strange.  Make sure that nothing
gets corrupted if we fork after calling vm86().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Stas Sergeev <stsp@list.ru>
Link: http://lkml.kernel.org/r/08f83295460a80e41dc5e3e81ec40d6844d316f5.1446270067.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-10-31 09:50:25 +01:00
Andy Lutomirski
893a3ec27e selftests/x86: Style fixes for the 'unwind_vdso' test
Checkpatch is really quite bad for user code like this, but it
caught two legit style issues.

Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.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/3335040bdd40d2bca4b1a28a3f8b165361c801b7.1444696194.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-14 16:56:28 +02:00
Andy Lutomirski
04235c00b6 selftests/x86: Add a test for ptrace syscall restart and arg modification
This tests assumptions about how fast syscall works wrt pt_regs
and, in particular, what happens if IP is decremented by 2
during a syscall.

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: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1c44dbfe59000ba135bbf35ccc5d2433a0b31618.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-07 11:34:07 +02:00
Andy Lutomirski
3b56aae34b selftests/x86: Add a test for vDSO unwinding
While the kernel itself doesn't use DWARF unwinding, user code
expects to be able to unwind the vDSO.  The vsyscall
(AT_SYSINFO) entry is manually CFI-annotated, and this tests
that it unwinds correctly.

I tested the test by incorrectly annotating __kernel_vsyscall,
and the test indeed fails if I do that.

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: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/8bf736d1925cdd165c0f980156a4248e55af47a1.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-07 11:34:06 +02:00
Denys Vlasenko
a58e2ecd01 x86/fpu/math-emu, selftests: Add test for FISTTP instructions
$ ./test_FISTTP_32
  [RUN]	Testing fisttp instructions
  [OK]	fisttp

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1442757790-27233-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-20 16:19:01 +02:00
Denys Vlasenko
57ca6897cd x86/fpu/math-emu, selftests: Add tests for FCMOV and FCOMI insns
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1442494933-13798-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-20 10:19:52 +02:00
Denys Vlasenko
c25be94f28 x86/asm/entry/32, selftests: Add 'test_syscall_vdso' test
This new test checks that all x86 registers are preserved across
32-bit syscalls. It tests syscalls through VDSO (if available)
and through INT 0x80, normally and under ptrace.

If kernel is a 64-bit one, high registers (r8..r15) are poisoned
before the syscall is called and are checked afterwards.

They must be either preserved, or cleared to zero (but r11 is
special); r12..15 must be preserved for INT 0x80.

EFLAGS is checked for changes too, but change there is not
considered to be a bug (paravirt kernels do not preserve
arithmetic flags).

Run-tested on 64-bit kernel:

	$ ./test_syscall_vdso_32
	[RUN]	Executing 6-argument 32-bit syscall via VDSO
	[OK]	Arguments are preserved across syscall
	[NOTE]	R11 has changed:0000000000200ed7 - assuming clobbered by
	SYSRET insn [OK]	R8..R15 did not leak kernel data
	[RUN]	Executing 6-argument 32-bit syscall via INT 80
	[OK]	Arguments are preserved across syscall
	[OK]	R8..R15 did not leak kernel data
	[RUN]	Running tests under ptrace
	[RUN]	Executing 6-argument 32-bit syscall via VDSO
	[OK]	Arguments are preserved across syscall
	[OK]	R8..R15 did not leak kernel data
	[RUN]	Executing 6-argument 32-bit syscall via INT 80
	[OK]	Arguments are preserved across syscall
	[OK]	R8..R15 did not leak kernel data

On 32-bit paravirt kernel:

	$ ./test_syscall_vdso_32
	[NOTE]	Not a 64-bit kernel, won't test R8..R15 leaks
	[RUN]	Executing 6-argument 32-bit syscall via VDSO
	[WARN]	Flags before=0000000000200ed7 id 0 00 o d i s z 0 a 0 p 1 c
	[WARN]	Flags  after=0000000000200246 id 0 00 i z 0 0 p 1
	[WARN]	Flags change=0000000000000c91 0 00 o d s 0 a 0 0 c
	[OK]	Arguments are preserved across syscall
	[RUN]	Executing 6-argument 32-bit syscall via INT 80
	[OK]	Arguments are preserved across syscall
	[RUN]	Running tests under ptrace
	[RUN]	Executing 6-argument 32-bit syscall via VDSO
	[OK]	Arguments are preserved across syscall
	[RUN]	Executing 6-argument 32-bit syscall via INT 80
	[OK]	Arguments are preserved across syscall

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.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: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1442427809-2027-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-18 09:40:48 +02:00