Commit Graph

27902 Commits

Author SHA1 Message Date
Vitaly Kuznetsov
a3b7424392 x86/hyperv: Clear vCPU banks between calls to avoid flushing unneeded vCPUs
hv_flush_pcpu_ex structures are not cleared between calls for performance
reasons (they're variable size up to PAGE_SIZE each) but we must clear
hv_vp_set.bank_contents part of it to avoid flushing unneeded vCPUs. The
rest of the structure is formed correctly.

To do the clearing in an efficient way stash the maximum possible vCPU
number (this may differ from Linux CPU id).

Reported-by: Jork Loeser <Jork.Loeser@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20171006154854.18092-1-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-10 12:53:00 +02:00
Colin Ian King
629eb703d3 perf/x86/intel/uncore: Fix memory leaks on allocation failures
Currently if an allocation fails then the error return paths
don't free up any currently allocated pmus[].boxes and pmus causing
a memory leak.  Add an error clean up exit path that frees these
objects.

Detected by CoverityScan, CID#711632 ("Resource Leak")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Fixes: 087bfbb032 ("perf/x86: Add generic Intel uncore PMU support")
Link: http://lkml.kernel.org/r/20171009172655.6132-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-10 12:51:07 +02:00
Josh Poimboeuf
d4a2d031dd x86/unwind: Disable unwinder warnings on 32-bit
x86-32 doesn't have stack validation, so in most cases it doesn't make
sense to warn about bad frame pointers.

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: LKP <lkp@01.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/a69658760800bf281e6353248c23e0fa0acf5230.1507597785.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-10 12:49:49 +02:00
Josh Poimboeuf
99bd28a49b x86/unwind: Align stack pointer in unwinder dump
When printing the unwinder dump, the stack pointer could be unaligned,
for one of two reasons:

- stack corruption; or

- GCC created an unaligned stack.

There's no way for the unwinder to tell the difference between the two,
so we have to assume one or the other.  GCC unaligned stacks are very
rare, and have only been spotted before GCC 5.  Presumably, if we're
doing an unwinder stack dump, stack corruption is more likely than a
GCC unaligned stack.  So always align the stack before starting the
dump.

Reported-and-tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: LKP <lkp@01.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/2f540c515946ab09ed267e1a1d6421202a0cce08.1507597785.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-10 12:49:49 +02:00
Josh Poimboeuf
5c99b692cf x86/unwind: Use MSB for frame pointer encoding on 32-bit
On x86-32, Tetsuo Handa and Fengguang Wu reported unwinder warnings
like:

  WARNING: kernel stack regs at f60bb9c8 in swapper:1 has bad 'bp' value 0ba00000

And also there were some stack dumps with a bunch of unreliable '?'
symbols after an apic_timer_interrupt symbol, meaning the unwinder got
confused when it tried to read the regs.

The cause of those issues is that, with GCC 4.8 (and possibly older),
there are cases where GCC misaligns the stack pointer in a leaf function
for no apparent reason:

  c124a388 <acpi_rs_move_data>:
  c124a388:       55                      push   %ebp
  c124a389:       89 e5                   mov    %esp,%ebp
  c124a38b:       57                      push   %edi
  c124a38c:       56                      push   %esi
  c124a38d:       89 d6                   mov    %edx,%esi
  c124a38f:       53                      push   %ebx
  c124a390:       31 db                   xor    %ebx,%ebx
  c124a392:       83 ec 03                sub    $0x3,%esp
  ...
  c124a3e3:       83 c4 03                add    $0x3,%esp
  c124a3e6:       5b                      pop    %ebx
  c124a3e7:       5e                      pop    %esi
  c124a3e8:       5f                      pop    %edi
  c124a3e9:       5d                      pop    %ebp
  c124a3ea:       c3                      ret

If an interrupt occurs in such a function, the regs on the stack will be
unaligned, which breaks the frame pointer encoding assumption.  So on
32-bit, use the MSB instead of the LSB to encode the regs.

This isn't an issue on 64-bit, because interrupts align the stack before
writing to it.

Reported-and-tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: LKP <lkp@01.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/279a26996a482ca716605c7dbc7f2db9d8d91e81.1507597785.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-10 12:49:48 +02:00
Josh Poimboeuf
62dd86ac01 x86/unwind: Fix dereference of untrusted pointer
Tetsuo Handa and Fengguang Wu reported a panic in the unwinder:

  BUG: unable to handle kernel NULL pointer dereference at 000001f2
  IP: update_stack_state+0xd4/0x340
  *pde = 00000000

  Oops: 0000 [] PREEMPT SMP
  CPU: 0 PID: 18728 Comm: 01-cpu-hotplug Not tainted 4.13.0-rc4-00170-gb09be67 
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014
  task: bb0b53c0 task.stack: bb3ac000
  EIP: update_stack_state+0xd4/0x340
  EFLAGS: 00010002 CPU: 0
  EAX: 0000a570 EBX: bb3adccb ECX: 0000f401 EDX: 0000a570
  ESI: 00000001 EDI: 000001ba EBP: bb3adc6b ESP: bb3adc3f
   DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
  CR0: 80050033 CR2: 000001f2 CR3: 0b3a7000 CR4: 00140690
  DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
  DR6: fffe0ff0 DR7: 00000400
  Call Trace:
   ? unwind_next_frame+0xea/0x400
   ? __unwind_start+0xf5/0x180
   ? __save_stack_trace+0x81/0x160
   ? save_stack_trace+0x20/0x30
   ? __lock_acquire+0xfa5/0x12f0
   ? lock_acquire+0x1c2/0x230
   ? tick_periodic+0x3a/0xf0
   ? _raw_spin_lock+0x42/0x50
   ? tick_periodic+0x3a/0xf0
   ? tick_periodic+0x3a/0xf0
   ? debug_smp_processor_id+0x12/0x20
   ? tick_handle_periodic+0x23/0xc0
   ? local_apic_timer_interrupt+0x63/0x70
   ? smp_trace_apic_timer_interrupt+0x235/0x6a0
   ? trace_apic_timer_interrupt+0x37/0x3c
   ? strrchr+0x23/0x50
  Code: 0f 95 c1 89 c7 89 45 e4 0f b6 c1 89 c6 89 45 dc 8b 04 85 98 cb 74 bc 88 4d e3 89 45 f0 83 c0 01 84 c9 89 04 b5 98 cb 74 bc 74 3b <8b> 47 38 8b 57 34 c6 43 1d 01 25 00 00 02 00 83 e2 03 09 d0 83
  EIP: update_stack_state+0xd4/0x340 SS:ESP: 0068:bb3adc3f
  CR2: 00000000000001f2
  ---[ end trace 0d147fd4aba8ff50 ]---
  Kernel panic - not syncing: Fatal exception in interrupt

On x86-32, after decoding a frame pointer to get a regs address,
regs_size() dereferences the regs pointer when it checks regs->cs to see
if the regs are user mode.  This is dangerous because it's possible that
what looks like a decoded frame pointer is actually a corrupt value, and
we don't want the unwinder to make things worse.

Instead of calling regs_size() on an unsafe pointer, just assume they're
kernel regs to start with.  Later, once it's safe to access the regs, we
can do the user mode check and corresponding safety check for the
remaining two regs.

Reported-and-tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: LKP <lkp@01.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 5ed8d8bb38 ("x86/unwind: Move common code into update_stack_state()")
Link: http://lkml.kernel.org/r/7f95b9a6993dec7674b3f3ab3dcd3294f7b9644d.1507597785.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-10 12:49:47 +02:00
Mathias Krause
6b32c126d3 x86/alternatives: Fix alt_max_short macro to really be a max()
The alt_max_short() macro in asm/alternative.h does not work as
intended, leading to nasty bugs. E.g. alt_max_short("1", "3")
evaluates to 3, but alt_max_short("3", "1") evaluates to 1 -- not
exactly the maximum of 1 and 3.

In fact, I had to learn it the hard way by crashing my kernel in not
so funny ways by attempting to make use of the ALTENATIVE_2 macro
with alternatives where the first one was larger than the second
one.

According to [1] and commit dbe4058a6a ("x86/alternatives: Fix
ALTERNATIVE_2 padding generation properly") the right handed side
should read "-(-(a < b))" not "-(-(a - b))". Fix that, to make the
macro work as intended.

While at it, fix up the comments regarding the additional "-", too.
It's not about gas' usage of s32 but brain dead logic of having a
"true" value of -1 for the < operator ... *sigh*

Btw., the one in asm/alternative-asm.h is correct. And, apparently,
all current users of ALTERNATIVE_2() pass same sized alternatives,
avoiding to hit the bug.

[1] http://graphics.stanford.edu/~seander/bithacks.html#IntegerMinOrMax

Reviewed-and-tested-by: Borislav Petkov <bp@suse.de>
Fixes: dbe4058a6a ("x86/alternatives: Fix ALTERNATIVE_2 padding generation properly")
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1507228213-13095-1-git-send-email-minipli@googlemail.com
2017-10-09 13:35:17 +02:00
Andy Lutomirski
924c6b900c x86/mm/64: Fix reboot interaction with CR4.PCIDE
Trying to reboot via real mode fails with PCID on: long mode cannot
be exited while CR4.PCIDE is set.  (No, I have no idea why, but the
SDM and actual CPUs are in agreement here.)  The result is a GPF and
a hang instead of a reboot.

I didn't catch this in testing because neither my computer nor my VM
reboots this way.  I can trigger it with reboot=bios, though.

Fixes: 660da7c922 ("x86/mm: Enable CR4.PCIDE on supported systems")
Reported-and-tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/f1e7d965998018450a7a70c2823873686a8b21c0.1507524746.git.luto@kernel.org
2017-10-09 13:31:04 +02:00
Linus Torvalds
8d473320ee KVM fixes for v4.14-rc4
- fix PPC XIVE interrupt delivery
 - fix x86 RCU breakage from asynchronous page faults when built without
   PREEMPT_COUNT
 - fix x86 build with -frecord-gcc-switches
 - fix x86 build without X86_LOCAL_APIC
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Radim Krčmář:

 - fix PPC XIVE interrupt delivery

 - fix x86 RCU breakage from asynchronous page faults when built without
   PREEMPT_COUNT

 - fix x86 build with -frecord-gcc-switches

 - fix x86 build without X86_LOCAL_APIC

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: add X86_LOCAL_APIC dependency
  x86/kvm: Move kvm_fastop_exception to .fixup section
  kvm/x86: Avoid async PF preempting the kernel incorrectly
  KVM: PPC: Book3S: Fix server always zero from kvmppc_xive_get_xive()
2017-10-06 11:28:34 -07:00
Linus Torvalds
27efed3e83 Merge branch 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull watchddog clean-up and fixes from Thomas Gleixner:
 "The watchdog (hard/softlockup detector) code is pretty much broken in
  its current state. The patch series addresses this by removing all
  duct tape and refactoring it into a workable state.

  The reasons why I ask for inclusion that late in the cycle are:

   1) The code causes lockdep splats vs. hotplug locking which get
      reported over and over. Unfortunately there is no easy fix.

   2) The risk of breakage is minimal because it's already broken

   3) As 4.14 is a long term stable kernel, I prefer to have working
      watchdog code in that and the lockdep issues resolved. I wouldn't
      ask you to pull if 4.14 wouldn't be a LTS kernel or if the
      solution would be easy to backport.

   4) The series was around before the merge window opened, but then got
      delayed due to the UP failure caused by the for_each_cpu()
      surprise which we discussed recently.

  Changes vs. V1:

   - Addressed your review points

   - Addressed the warning in the powerpc code which was discovered late

   - Changed two function names which made sense up to a certain point
     in the series. Now they match what they do in the end.

   - Fixed a 'unused variable' warning, which got not detected by the
     intel robot. I triggered it when trying all possible related config
     combinations manually. Randconfig testing seems not random enough.

  The changes have been tested by and reviewed by Don Zickus and tested
  and acked by Micheal Ellerman for powerpc"

* 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  watchdog/core: Put softlockup_threads_initialized under ifdef guard
  watchdog/core: Rename some softlockup_* functions
  powerpc/watchdog: Make use of watchdog_nmi_probe()
  watchdog/core, powerpc: Lock cpus across reconfiguration
  watchdog/core, powerpc: Replace watchdog_nmi_reconfigure()
  watchdog/hardlockup/perf: Fix spelling mistake: "permanetely" -> "permanently"
  watchdog/hardlockup/perf: Cure UP damage
  watchdog/hardlockup: Clean up hotplug locking mess
  watchdog/hardlockup/perf: Simplify deferred event destroy
  watchdog/hardlockup/perf: Use new perf CPU enable mechanism
  watchdog/hardlockup/perf: Implement CPU enable replacement
  watchdog/hardlockup/perf: Implement init time detection of perf
  watchdog/hardlockup/perf: Implement init time perf validation
  watchdog/core: Get rid of the racy update loop
  watchdog/core, powerpc: Make watchdog_nmi_reconfigure() two stage
  watchdog/sysctl: Clean up sysctl variable name space
  watchdog/sysctl: Get rid of the #ifdeffery
  watchdog/core: Clean up header mess
  watchdog/core: Further simplify sysctl handling
  watchdog/core: Get rid of the thread teardown/setup dance
  ...
2017-10-06 08:36:41 -07:00
Arnd Bergmann
e42eef4ba3 KVM: add X86_LOCAL_APIC dependency
The rework of the posted interrupt handling broke building without
support for the local APIC:

ERROR: "boot_cpu_physical_apicid" [arch/x86/kvm/kvm-intel.ko] undefined!

That configuration is probably not particularly useful anyway, so
we can avoid the randconfig failures by adding a Kconfig dependency.

Fixes: 8b306e2f3c ("KVM: VMX: avoid double list add with VT-d posted interrupts")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-10-05 19:55:48 +02:00
Linus Torvalds
9a431ef962 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Check iwlwifi 9000 reorder buffer out-of-space condition properly,
    from Sara Sharon.

 2) Fix RCU splat in qualcomm rmnet driver, from Subash Abhinov
    Kasiviswanathan.

 3) Fix session and tunnel release races in l2tp, from Guillaume Nault
    and Sabrina Dubroca.

 4) Fix endian bug in sctp_diag_dump(), from Dan Carpenter.

 5) Several mlx5 driver fixes from the Mellanox folks (max flow counters
    cap check, invalid memory access in IPoIB support, etc.)

 6) tun_get_user() should bail if skb->len is zero, from Alexander
    Potapenko.

 7) Fix RCU lookups in inetpeer, from Eric Dumazet.

 8) Fix locking in packet_do_bund().

 9) Handle cb->start() error properly in netlink dump code, from Jason
    A. Donenfeld.

10) Handle multicast properly in UDP socket early demux code. From Paolo
    Abeni.

11) Several erspan bug fixes in ip_gre, from Xin Long.

12) Fix use-after-free in socket filter code, in order to handle the
    fact that listener lock is no longer taken during the three-way TCP
    handshake. From Eric Dumazet.

13) Fix infoleak in RTM_GETSTATS, from Nikolay Aleksandrov.

14) Fix tail call generation in x86-64 BPF JIT, from Alexei Starovoitov.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits)
  net: 8021q: skip packets if the vlan is down
  bpf: fix bpf_tail_call() x64 JIT
  net: stmmac: dwmac-rk: Add RK3128 GMAC support
  rndis_host: support Novatel Verizon USB730L
  net: rtnetlink: fix info leak in RTM_GETSTATS call
  socket, bpf: fix possible use after free
  mlxsw: spectrum_router: Track RIF of IPIP next hops
  mlxsw: spectrum_router: Move VRF refcounting
  net: hns3: Fix an error handling path in 'hclge_rss_init_hw()'
  net: mvpp2: Fix clock resource by adding an optional bus clock
  r8152: add Linksys USB3GIGV1 id
  l2tp: fix l2tp_eth module loading
  ip_gre: erspan device should keep dst
  ip_gre: set tunnel hlen properly in erspan_tunnel_init
  ip_gre: check packet length and mtu correctly in erspan_xmit
  ip_gre: get key from session_id correctly in erspan_rcv
  tipc: use only positive error codes in messages
  ppp: fix __percpu annotation
  udp: perform source validation for mcast early demux
  IPv4: early demux can return an error code
  ...
2017-10-05 08:40:09 -07:00
Josh Poimboeuf
f26e60167d x86/kvm: Move kvm_fastop_exception to .fixup section
When compiling the kernel with the '-frecord-gcc-switches' flag, objtool
complains:

  arch/x86/kvm/emulate.o: warning: objtool: .GCC.command.line+0x0: special: can't find new instruction

And also the kernel fails to link.

The problem is that the 'kvm_fastop_exception' code gets placed into the
throwaway '.GCC.command.line' section instead of '.text'.

Exception fixup code is conventionally placed in the '.fixup' section,
so put it there where it belongs.

Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-10-05 15:06:30 +02:00
Borislav Petkov
262e681183 x86/mce: Hide mca_cfg
Now that lguest is gone, put it in the internal header which should be
used only by MCA/RAS code.

Add missing header guards while at it.

No functional change.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20171002092836.22971-3-bp@alien8.de
2017-10-05 14:23:06 +02:00
Boqun Feng
a2b7861bb3 kvm/x86: Avoid async PF preempting the kernel incorrectly
Currently, in PREEMPT_COUNT=n kernel, kvm_async_pf_task_wait() could call
schedule() to reschedule in some cases.  This could result in
accidentally ending the current RCU read-side critical section early,
causing random memory corruption in the guest, or otherwise preempting
the currently running task inside between preempt_disable and
preempt_enable.

The difficulty to handle this well is because we don't know whether an
async PF delivered in a preemptible section or RCU read-side critical section
for PREEMPT_COUNT=n, since preempt_disable()/enable() and rcu_read_lock/unlock()
are both no-ops in that case.

To cure this, we treat any async PF interrupting a kernel context as one
that cannot be preempted, preventing kvm_async_pf_task_wait() from choosing
the schedule() path in that case.

To do so, a second parameter for kvm_async_pf_task_wait() is introduced,
so that we know whether it's called from a context interrupting the
kernel, and the parameter is set properly in all the callsites.

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-10-04 18:28:53 +02:00
Alexei Starovoitov
90caccdd8c bpf: fix bpf_tail_call() x64 JIT
- bpf prog_array just like all other types of bpf array accepts 32-bit index.
  Clarify that in the comment.
- fix x64 JIT of bpf_tail_call which was incorrectly loading 8 instead of 4 bytes
- tighten corresponding check in the interpreter to stay consistent

The JIT bug can be triggered after introduction of BPF_F_NUMA_NODE flag
in commit 96eabe7a40 in 4.14. Before that the map_flags would stay zero and
though JIT code is wrong it will check bounds correctly.
Hence two fixes tags. All other JITs don't have this problem.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Fixes: 96eabe7a40 ("bpf: Allow selecting numa node during map creation")
Fixes: b52f00e6a7 ("x86: bpf_jit: implement bpf_tail_call() helper")
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-03 16:04:44 -07:00
Masami Hiramatsu
b664d57f39 kprobes/x86: Remove IRQ disabling from jprobe handlers
Jprobes actually don't need to disable IRQs while calling
handlers, because of how we specify the kernel interface in
Documentation/kprobes.txt:

-----
 Probe handlers are run with preemption disabled.  Depending on the
 architecture and optimization state, handlers may also run with
 interrupts disabled (e.g., kretprobe handlers and optimized kprobe
 handlers run without interrupt disabled on x86/x86-64).
-----

So let's remove IRQ disabling from jprobes too.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/150701508194.32266.14458959863314097305.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-03 19:11:48 +02:00
Josh Poimboeuf
ee213fc72f kprobes/x86: Set up frame pointer in kprobe trampoline
Richard Weinberger saw an unwinder warning when running bcc's opensnoop:

  WARNING: kernel stack frame pointer at ffff99ef4076bea0 in opensnoop:2008 has bad value 0000000000000008
  unwind stack type:0 next_sp:          (null) mask:0x2 graph_idx:0
  ...
  ffff99ef4076be88: ffff99ef4076bea0 (0xffff99ef4076bea0)
  ffff99ef4076be90: ffffffffac442721 (optimized_callback +0x81/0x90)
  ...

A lockdep stack trace was initiated from inside a kprobe handler, when
the unwinder noticed a bad frame pointer on the stack.  The bad frame
pointer is related to the fact that the kprobe optprobe trampoline
doesn't save the frame pointer before calling into optimized_callback().

Reported-and-tested-by: Richard Weinberger <richard@sigma-star.at>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
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/7aef2f8ecd75c2f505ef9b80490412262cf4a44c.1507038547.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-03 19:11:27 +02:00
Linus Torvalds
368f89984b Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "This contains the following fixes and improvements:

   - Avoid dereferencing an unprotected VMA pointer in the fault signal
     generation code

   - Fix inline asm call constraints for GCC 4.4

   - Use existing register variable to retrieve the stack pointer
     instead of forcing the compiler to create another indirect access
     which results in excessive extra 'mov %rsp, %<dst>' instructions

   - Disable branch profiling for the memory encryption code to prevent
     an early boot crash

   - Fix a sparse warning caused by casting the __user annotation in
     __get_user_asm_u64() away

   - Fix an off by one error in the loop termination of the error patch
     in the x86 sysfs init code

   - Add missing CPU IDs to various Intel specific drivers to enable the
     functionality on recent hardware

   - More (init) constification in the numachip code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asm: Use register variable to get stack pointer value
  x86/mm: Disable branch profiling in mem_encrypt.c
  x86/asm: Fix inline asm call constraints for GCC 4.4
  perf/x86/intel/uncore: Correct num_boxes for IIO and IRP
  perf/x86/intel/rapl: Add missing CPU IDs
  perf/x86/msr: Add missing CPU IDs
  perf/x86/intel/cstate: Add missing CPU IDs
  x86: Don't cast away the __user in __get_user_asm_u64()
  x86/sysfs: Fix off-by-one error in loop termination
  x86/mm: Fix fault error path using unsafe vma pointer
  x86/numachip: Add const and __initconst to numachip2_clockevent
2017-10-01 13:55:32 -07:00
Linus Torvalds
9f2a5128b9 xen: fixes for 4.14-rc3
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Merge tag 'for-linus-4.14c-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - avoid a warning when compiling with clang

 - consider read-only bits in xen-pciback when writing to a BAR

 - fix a boot crash of pv-domains

* tag 'for-linus-4.14c-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/mmu: Call xen_cleanhighmap() with 4MB aligned for page tables mapping
  xen-pciback: relax BAR sizing write value check
  x86/xen: clean up clang build warning
2017-09-29 12:24:28 -07:00
Linus Torvalds
42057e1825 Mixed bugfixes. Perhaps the most interesting one is a latent bug
that was finally triggered by PCID support.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Mixed bugfixes. Perhaps the most interesting one is a latent bug that
  was finally triggered by PCID support"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm/x86: Handle async PF in RCU read-side critical sections
  KVM: nVMX: Fix nested #PF intends to break L1's vmlauch/vmresume
  KVM: VMX: use cmpxchg64
  KVM: VMX: simplify and fix vmx_vcpu_pi_load
  KVM: VMX: avoid double list add with VT-d posted interrupts
  KVM: VMX: extract __pi_post_block
  KVM: PPC: Book3S HV: Check for updated HDSISR on P9 HDSI exception
  KVM: nVMX: fix HOST_CR3/HOST_CR4 cache
2017-09-29 12:18:55 -07:00
Andrey Ryabinin
196bd485ee x86/asm: Use register variable to get stack pointer value
Currently we use current_stack_pointer() function to get the value
of the stack pointer register. Since commit:

  f5caf621ee ("x86/asm: Fix inline asm call constraints for Clang")

... we have a stack register variable declared. It can be used instead of
current_stack_pointer() function which allows to optimize away some
excessive "mov %rsp, %<dst>" instructions:

 -mov    %rsp,%rdx
 -sub    %rdx,%rax
 -cmp    $0x3fff,%rax
 -ja     ffffffff810722fd <ist_begin_non_atomic+0x2d>

 +sub    %rsp,%rax
 +cmp    $0x3fff,%rax
 +ja     ffffffff810722fa <ist_begin_non_atomic+0x2a>

Remove current_stack_pointer(), rename __asm_call_sp to current_stack_pointer
and use it instead of the removed function.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <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/20170929141537.29167-1-aryabinin@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-29 19:39:44 +02:00
Tom Lendacky
bc829ee36e x86/mm: Disable branch profiling in mem_encrypt.c
Some routines in mem_encrypt.c are called very early in the boot process,
e.g. sme_encrypt_kernel(). When CONFIG_TRACE_BRANCH_PROFILING=y is defined
the resulting branch profiling associated with the check to see if SME is
active results in a kernel crash. Disable branch profiling for
mem_encrypt.c by defining DISABLE_BRANCH_PROFILING before including any
header files.

Reported-by: kernel test robot <lkp@01.org>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170929162419.6016.53390.stgit@tlendack-t1.amdoffice.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-29 19:37:51 +02:00
Boqun Feng
b862789aa5 kvm/x86: Handle async PF in RCU read-side critical sections
Sasha Levin reported a WARNING:

| WARNING: CPU: 0 PID: 6974 at kernel/rcu/tree_plugin.h:329
| rcu_preempt_note_context_switch kernel/rcu/tree_plugin.h:329 [inline]
| WARNING: CPU: 0 PID: 6974 at kernel/rcu/tree_plugin.h:329
| rcu_note_context_switch+0x16c/0x2210 kernel/rcu/tree.c:458
...
| CPU: 0 PID: 6974 Comm: syz-fuzzer Not tainted 4.13.0-next-20170908+ 
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
| 1.10.1-1ubuntu1 04/01/2014
| Call Trace:
...
| RIP: 0010:rcu_preempt_note_context_switch kernel/rcu/tree_plugin.h:329 [inline]
| RIP: 0010:rcu_note_context_switch+0x16c/0x2210 kernel/rcu/tree.c:458
| RSP: 0018:ffff88003b2debc8 EFLAGS: 00010002
| RAX: 0000000000000001 RBX: 1ffff1000765bd85 RCX: 0000000000000000
| RDX: 1ffff100075d7882 RSI: ffffffffb5c7da20 RDI: ffff88003aebc410
| RBP: ffff88003b2def30 R08: dffffc0000000000 R09: 0000000000000001
| R10: 0000000000000000 R11: 0000000000000000 R12: ffff88003b2def08
| R13: 0000000000000000 R14: ffff88003aebc040 R15: ffff88003aebc040
| __schedule+0x201/0x2240 kernel/sched/core.c:3292
| schedule+0x113/0x460 kernel/sched/core.c:3421
| kvm_async_pf_task_wait+0x43f/0x940 arch/x86/kernel/kvm.c:158
| do_async_page_fault+0x72/0x90 arch/x86/kernel/kvm.c:271
| async_page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1069
| RIP: 0010:format_decode+0x240/0x830 lib/vsprintf.c:1996
| RSP: 0018:ffff88003b2df520 EFLAGS: 00010283
| RAX: 000000000000003f RBX: ffffffffb5d1e141 RCX: ffff88003b2df670
| RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffffffffb5d1e140
| RBP: ffff88003b2df560 R08: dffffc0000000000 R09: 0000000000000000
| R10: ffff88003b2df718 R11: 0000000000000000 R12: ffff88003b2df5d8
| R13: 0000000000000064 R14: ffffffffb5d1e140 R15: 0000000000000000
| vsnprintf+0x173/0x1700 lib/vsprintf.c:2136
| sprintf+0xbe/0xf0 lib/vsprintf.c:2386
| proc_self_get_link+0xfb/0x1c0 fs/proc/self.c:23
| get_link fs/namei.c:1047 [inline]
| link_path_walk+0x1041/0x1490 fs/namei.c:2127
...

This happened when the host hit a page fault, and delivered it as in an
async page fault, while the guest was in an RCU read-side critical
section.  The guest then tries to reschedule in kvm_async_pf_task_wait(),
but rcu_preempt_note_context_switch() would treat the reschedule as a
sleep in RCU read-side critical section, which is not allowed (even in
preemptible RCU).  Thus the WARN.

To cure this, make kvm_async_pf_task_wait() go to the halt path if the
PF happens in a RCU read-side critical section.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-29 17:05:17 +02:00
Wanpeng Li
305d0ab476 KVM: nVMX: Fix nested #PF intends to break L1's vmlauch/vmresume
------------[ cut here ]------------
 WARNING: CPU: 4 PID: 5280 at /home/kernel/linux/arch/x86/kvm//vmx.c:11394 nested_vmx_vmexit+0xc2b/0xd70 [kvm_intel]
 CPU: 4 PID: 5280 Comm: qemu-system-x86 Tainted: G        W  OE   4.13.0+ 
 RIP: 0010:nested_vmx_vmexit+0xc2b/0xd70 [kvm_intel]
 Call Trace:
  ? emulator_read_emulated+0x15/0x20 [kvm]
  ? segmented_read+0xae/0xf0 [kvm]
  vmx_inject_page_fault_nested+0x60/0x70 [kvm_intel]
  ? vmx_inject_page_fault_nested+0x60/0x70 [kvm_intel]
  x86_emulate_instruction+0x733/0x810 [kvm]
  vmx_handle_exit+0x2f4/0xda0 [kvm_intel]
  ? kvm_arch_vcpu_ioctl_run+0xd2f/0x1c60 [kvm]
  kvm_arch_vcpu_ioctl_run+0xdab/0x1c60 [kvm]
  ? kvm_arch_vcpu_load+0x62/0x230 [kvm]
  kvm_vcpu_ioctl+0x340/0x700 [kvm]
  ? kvm_vcpu_ioctl+0x340/0x700 [kvm]
  ? __fget+0xfc/0x210
  do_vfs_ioctl+0xa4/0x6a0
  ? __fget+0x11d/0x210
  SyS_ioctl+0x79/0x90
  entry_SYSCALL_64_fastpath+0x23/0xc2

A nested #PF is triggered during L0 emulating instruction for L2. However, it
doesn't consider we should not break L1's vmlauch/vmresme. This patch fixes
it by queuing the #PF exception instead ,requesting an immediate VM exit from
L2 and keeping the exception for L1 pending for a subsequent nested VM exit.

This should actually work all the time, making vmx_inject_page_fault_nested
totally unnecessary.  However, that's not working yet, so this patch can work
around the issue in the meanwhile.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-29 16:30:37 +02:00
Josh Poimboeuf
520a13c530 x86/asm: Fix inline asm call constraints for GCC 4.4
The kernel test bot (run by Xiaolong Ye) reported that the following commit:

  f5caf621ee ("x86/asm: Fix inline asm call constraints for Clang")

is causing double faults in a kernel compiled with GCC 4.4.

Linus subsequently diagnosed the crash pattern and the buggy commit and found that
the issue is with this code:

  register unsigned int __asm_call_sp asm("esp");
  #define ASM_CALL_CONSTRAINT "+r" (__asm_call_sp)

Even on a 64-bit kernel, it's using ESP instead of RSP.  That causes GCC
to produce the following bogus code:

  ffffffff8147461d:       89 e0                   mov    %esp,%eax
  ffffffff8147461f:       4c 89 f7                mov    %r14,%rdi
  ffffffff81474622:       4c 89 fe                mov    %r15,%rsi
  ffffffff81474625:       ba 20 00 00 00          mov    $0x20,%edx
  ffffffff8147462a:       89 c4                   mov    %eax,%esp
  ffffffff8147462c:       e8 bf 52 05 00          callq  ffffffff814c98f0 <copy_user_generic_unrolled>

Despite the absurdity of it backing up and restoring the stack pointer
for no reason, the bug is actually the fact that it's only backing up
and restoring the lower 32 bits of the stack pointer.  The upper 32 bits
are getting cleared out, corrupting the stack pointer.

So change the '__asm_call_sp' register variable to be associated with
the actual full-size stack pointer.

This also requires changing the __ASM_SEL() macro to be based on the
actual compiled arch size, rather than the CONFIG value, because
CONFIG_X86_64 compiles some files with '-m32' (e.g., realmode and vdso).
Otherwise Clang fails to build the kernel because it complains about the
use of a 64-bit register (RSP) in a 32-bit file.

Reported-and-Bisected-and-Tested-by: kernel test robot <xiaolong.ye@intel.com>
Diagnosed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: LKP <lkp@01.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: f5caf621ee ("x86/asm: Fix inline asm call constraints for Clang")
Link: http://lkml.kernel.org/r/20170928215826.6sdpmwtkiydiytim@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-29 13:15:44 +02:00
Paolo Bonzini
c0a1666bcb KVM: VMX: use cmpxchg64
This fixes a compilation failure on 32-bit systems.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-28 17:58:41 +02:00
Zhenzhong Duan
0d805ee70a xen/mmu: Call xen_cleanhighmap() with 4MB aligned for page tables mapping
When bootup a PVM guest with large memory(Ex.240GB), XEN provided initial
mapping overlaps with kernel module virtual space. When mapping in this space
is cleared by xen_cleanhighmap(), in certain case there could be an 2MB mapping
left. This is due to XEN initialize 4MB aligned mapping but xen_cleanhighmap()
finish at 2MB boundary.

When module loading is just on top of the 2MB space, got below warning:

WARNING: at mm/vmalloc.c:106 vmap_pte_range+0x14e/0x190()
Call Trace:
 [<ffffffff81117083>] warn_alloc_failed+0xf3/0x160
 [<ffffffff81146022>] __vmalloc_area_node+0x182/0x1c0
 [<ffffffff810ac91e>] ? module_alloc_update_bounds+0x1e/0x80
 [<ffffffff81145df7>] __vmalloc_node_range+0xa7/0x110
 [<ffffffff810ac91e>] ? module_alloc_update_bounds+0x1e/0x80
 [<ffffffff8103ca54>] module_alloc+0x64/0x70
 [<ffffffff810ac91e>] ? module_alloc_update_bounds+0x1e/0x80
 [<ffffffff810ac91e>] module_alloc_update_bounds+0x1e/0x80
 [<ffffffff810ac9a7>] move_module+0x27/0x150
 [<ffffffff810aefa0>] layout_and_allocate+0x120/0x1b0
 [<ffffffff810af0a8>] load_module+0x78/0x640
 [<ffffffff811ff90b>] ? security_file_permission+0x8b/0x90
 [<ffffffff810af6d2>] sys_init_module+0x62/0x1e0
 [<ffffffff815154c2>] system_call_fastpath+0x16/0x1b

Then the mapping of 2MB is cleared, finally oops when the page in that space is
accessed.

BUG: unable to handle kernel paging request at ffff880022600000
IP: [<ffffffff81260877>] clear_page_c_e+0x7/0x10
PGD 1788067 PUD 178c067 PMD 22434067 PTE 0
Oops: 0002 [] SMP
Call Trace:
 [<ffffffff81116ef7>] ? prep_new_page+0x127/0x1c0
 [<ffffffff81117d42>] get_page_from_freelist+0x1e2/0x550
 [<ffffffff81133010>] ? ii_iovec_copy_to_user+0x90/0x140
 [<ffffffff81119c9d>] __alloc_pages_nodemask+0x12d/0x230
 [<ffffffff81155516>] alloc_pages_vma+0xc6/0x1a0
 [<ffffffff81006ffd>] ? pte_mfn_to_pfn+0x7d/0x100
 [<ffffffff81134cfb>] do_anonymous_page+0x16b/0x350
 [<ffffffff81139c34>] handle_pte_fault+0x1e4/0x200
 [<ffffffff8100712e>] ? xen_pmd_val+0xe/0x10
 [<ffffffff810052c9>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e
 [<ffffffff81139dab>] handle_mm_fault+0x15b/0x270
 [<ffffffff81510c10>] do_page_fault+0x140/0x470
 [<ffffffff8150d7d5>] page_fault+0x25/0x30

Call xen_cleanhighmap() with 4MB aligned for page tables mapping to fix it.
The unnecessory call of xen_cleanhighmap() in DEBUG mode is also removed.

-v2: add comment about XEN alignment from Juergen.

References: https://lists.xen.org/archives/html/xen-devel/2012-07/msg01562.html
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>

[boris: added 'xen/mmu' tag to commit subject]
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-09-28 08:26:30 -04:00
Josh Poimboeuf
2704fbb672 x86/head: Add unwind hint annotations
Jiri Slaby reported an ORC issue when unwinding from an idle task.  The
stack was:

    ffffffff811083c2 do_idle+0x142/0x1e0
    ffffffff8110861d cpu_startup_entry+0x5d/0x60
    ffffffff82715f58 start_kernel+0x3ff/0x407
    ffffffff827153e8 x86_64_start_kernel+0x14e/0x15d
    ffffffff810001bf secondary_startup_64+0x9f/0xa0

The ORC unwinder errored out at secondary_startup_64 because the head
code isn't annotated yet so there wasn't a corresponding ORC entry.

Fix that and any other head-related unwinding issues by adding unwind
hints to the head code.

Reported-by: Jiri Slaby <jslaby@suse.cz>
Tested-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@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/78ef000a2f68f545d6eef44ee912edceaad82ccf.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:04 +02:00
Josh Poimboeuf
abbe1cac62 x86/xen: Add unwind hint annotations
Add unwind hint annotations to the xen head code so the ORC unwinder can
read head_64.o.

hypercall_page needs empty annotations at 32-byte intervals to match the
'xen_hypercall_*' ELF functions at those locations.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@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/70ed2eb516fe9266be766d953f93c2571bca88cc.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:03 +02:00
Josh Poimboeuf
2582d3df95 x86/xen: Fix xen head ELF annotations
Mark the ends of the startup_xen and hypercall_page code sections.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@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/3a80a394d30af43d9cefa1a29628c45ed8420c97.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:03 +02:00
Josh Poimboeuf
e93db75a00 x86/boot: Annotate verify_cpu() as a callable function
verify_cpu() is a callable function.  Annotate it as such.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@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/293024b8a080832075312f38c07ccc970fc70292.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:03 +02:00
Josh Poimboeuf
015a2ea547 x86/head: Fix head ELF function annotations
These functions aren't callable C-type functions, so don't annotate them
as such.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@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/36eb182738c28514f8bf95e403d89b6413a88883.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:03 +02:00
Josh Poimboeuf
a8b88e84d1 x86/head: Remove unused 'bad_address' code
It's no longer possible for this code to be executed, so remove it.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@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/32a46fe92d2083700599b36872b26e7dfd7b7965.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:03 +02:00
Josh Poimboeuf
17270717e8 x86/head: Remove confusing comment
This comment is actively wrong and confusing.  It refers to the
registers' stack offsets after the pt_regs has been constructed on the
stack, but this code is *before* that.

At this point the stack just has the standard iret frame, for which no
comment should be needed.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@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/a3c267b770fc56c9b86df9c11c552848248aace2.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:02 +02:00
Paolo Bonzini
31afb2ea2b KVM: VMX: simplify and fix vmx_vcpu_pi_load
The simplify part: do not touch pi_desc.nv, we can set it when the
VCPU is first created.  Likewise, pi_desc.sn is only handled by
vmx_vcpu_pi_load, do not touch it in __pi_post_block.

The fix part: do not check kvm_arch_has_assigned_device, instead
check the SN bit to figure out whether vmx_vcpu_pi_put ran before.
This matches what the previous patch did in pi_post_block.

Cc: Huangweidong <weidong.huang@huawei.com>
Cc: Gonglei <arei.gonglei@huawei.com>
Cc: wangxin <wangxinxin.wang@huawei.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Tested-by: Longpeng (Mike) <longpeng2@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-27 13:45:42 +02:00
Paolo Bonzini
8b306e2f3c KVM: VMX: avoid double list add with VT-d posted interrupts
In some cases, for example involving hot-unplug of assigned
devices, pi_post_block can forget to remove the vCPU from the
blocked_vcpu_list.  When this happens, the next call to
pi_pre_block corrupts the list.

Fix this in two ways.  First, check vcpu->pre_pcpu in pi_pre_block
and WARN instead of adding the element twice in the list.  Second,
always do the list removal in pi_post_block if vcpu->pre_pcpu is
set (not -1).

The new code keeps interrupts disabled for the whole duration of
pi_pre_block/pi_post_block.  This is not strictly necessary, but
easier to follow.  For the same reason, PI.ON is checked only
after the cmpxchg, and to handle it we just call the post-block
code.  This removes duplication of the list removal code.

Cc: Huangweidong <weidong.huang@huawei.com>
Cc: Gonglei <arei.gonglei@huawei.com>
Cc: wangxin <wangxinxin.wang@huawei.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Tested-by: Longpeng (Mike) <longpeng2@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-27 13:45:37 +02:00
Paolo Bonzini
cd39e1176d KVM: VMX: extract __pi_post_block
Simple code movement patch, preparing for the next one.

Cc: Huangweidong <weidong.huang@huawei.com>
Cc: Gonglei <arei.gonglei@huawei.com>
Cc: wangxin <wangxinxin.wang@huawei.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Tested-by: Longpeng (Mike) <longpeng2@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-27 13:45:28 +02:00
Ingo Molnar
8474c532b5 Merge branch 'WIP.x86/fpu' into x86/fpu, because it's ready
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 10:17:43 +02:00
Eric Biggers
738f48cb5f x86/fpu: Use using_compacted_format() instead of open coded X86_FEATURE_XSAVES
This is the canonical method to use.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-11-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:48 +02:00
Eric Biggers
98c0fad9d6 x86/fpu: Use validate_xstate_header() to validate the xstate_header in copy_user_to_xstate()
Tighten the checks in copy_user_to_xstate().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-10-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:48 +02:00
Eric Biggers
3d703477bc x86/fpu: Eliminate the 'xfeatures' local variable in copy_user_to_xstate()
We now have this field in hdr.xfeatures.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-9-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:48 +02:00
Eric Biggers
af2c4322d9 x86/fpu: Copy the full header in copy_user_to_xstate()
This is in preparation to verify the full xstate header as supplied by user-space.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-8-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:47 +02:00
Eric Biggers
af95774b3c x86/fpu: Use validate_xstate_header() to validate the xstate_header in copy_kernel_to_xstate()
Tighten the checks in copy_kernel_to_xstate().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-7-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:47 +02:00
Eric Biggers
b89eda482d x86/fpu: Eliminate the 'xfeatures' local variable in copy_kernel_to_xstate()
We have this information in the xstate_header.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-6-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:46 +02:00
Eric Biggers
80d8ae86b3 x86/fpu: Copy the full state_header in copy_kernel_to_xstate()
This is in preparation to verify the full xstate header as supplied by user-space.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-5-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:46 +02:00
Eric Biggers
b11e2e18a7 x86/fpu: Use validate_xstate_header() to validate the xstate_header in __fpu__restore_sig()
Tighten the checks in __fpu__restore_sig() and update comments.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-4-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:46 +02:00
Eric Biggers
cf9df81b13 x86/fpu: Use validate_xstate_header() to validate the xstate_header in xstateregs_set()
Tighten the checks in xstateregs_set().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-3-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:45 +02:00
Eric Biggers
e63e5d5c15 x86/fpu: Introduce validate_xstate_header()
Move validation of user-supplied xstate_header into a helper function,
in preparation of calling it from both the ptrace and sigreturn syscall
paths.

The new function also considers it to be an error if *any* reserved bits
are set, whereas before we were just clearing most of them silently.

This should reduce the chance of bugs that fail to correctly validate
user-supplied XSAVE areas.  It also will expose any broken userspace
programs that set the other reserved bits; this is desirable because
such programs will lose compatibility with future CPUs and kernels if
those bits are ever used for anything.  (There shouldn't be any such
programs, and in fact in the case where the compacted format is in use
we were already validating xfeatures.  But you never know...)

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
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: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-2-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:45 +02:00
Ingo Molnar
369a036de2 x86/fpu: Rename fpu__activate_fpstate_read/write() to fpu__prepare_[read|write]()
As per the new nomenclature we don't 'activate' the FPU state
anymore, we initialize it. So drop the _activate_fpstate name
from these functions, which were a bit of a mouthful anyway,
and name them:

	fpu__prepare_read()
	fpu__prepare_write()

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.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>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:44 +02:00
Ingo Molnar
2ce03d850b x86/fpu: Rename fpu__activate_curr() to fpu__initialize()
Rename this function to better express that it's all about
initializing the FPU state of a task which goes hand in hand
with the fpu::initialized field.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-33-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:44 +02:00
Ingo Molnar
e10078eba6 x86/fpu: Simplify and speed up fpu__copy()
fpu__copy() has a preempt_disable()/enable() pair, which it had to do to
be able to atomically unlazy the current task when doing an FNSAVE.

But we don't unlazy tasks anymore, we always do direct saves/restores of
FPU context.

So remove both the unnecessary critical section, and update the comments.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-32-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:44 +02:00
Ingo Molnar
7f1487c59b x86/fpu: Fix stale comments about lazy FPU logic
We don't do any lazy restore anymore, what we have are two pieces of optimization:

 - no-FPU tasks that don't save/restore the FPU context (kernel threads are such)

 - cached FPU registers maintained via the fpu->last_cpu field. This means that
   if an FPU task context switches to a non-FPU task then we can maintain the
   FPU registers as an in-FPU copies (cache), and skip the restoration of them
   once we switch back to the original FPU-using task.

Update all the comments that still referred to old 'lazy' and 'unlazy' concepts.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-31-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:43 +02:00
Ingo Molnar
e4a81bfcaa x86/fpu: Rename fpu::fpstate_active to fpu::initialized
The x86 FPU code used to have a complex state machine where both the FPU
registers and the FPU state context could be 'active' (or inactive)
independently of each other - which enabled features like lazy FPU restore.

Much of this complexity is gone in the current code: now we basically can
have FPU-less tasks (kernel threads) that don't use (and save/restore) FPU
state at all, plus full FPU users that save/restore directly with no laziness
whatsoever.

But the fpu::fpstate_active still carries bits of the old complexity - meanwhile
this flag has become a simple flag that shows whether the FPU context saving
area in the thread struct is initialized and used, or not.

Rename it to fpu::initialized to express this simplicity in the name as well.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-30-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:36 +02:00
Ingo Molnar
685c930d6e x86/fpu: Remove fpu__current_fpstate_write_begin/end()
These functions are not used anymore, so remove them.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-29-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:42:20 +02:00
Ingo Molnar
4618e90965 x86/fpu: Fix fpu__activate_fpstate_read() and update comments
fpu__activate_fpstate_read() can be called for the current task
when coredumping - or for stopped tasks when ptrace-ing.

Implement this properly in the code and update the comments.

This also fixes an incorrect (but harmless) warning introduced by
one of the earlier patches.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-28-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:41:09 +02:00
Kan Liang
29b46dfb13 perf/x86/intel/uncore: Correct num_boxes for IIO and IRP
There are 6 IIO/IRP boxes for CBDMA, PCIe0-2, MCP 0 and MCP 1
separately. Correct the num_boxes.

Signed-off-by: Kan Liang <Kan.liang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: acme@kernel.org
Link: http://lkml.kernel.org/r/1505149816-12580-1-git-send-email-kan.liang@intel.com
2017-09-25 12:43:56 +02:00
Kan Liang
450a978935 perf/x86/intel/rapl: Add missing CPU IDs
DENVERTON and GEMINI_LAKE support same RAPL counters as Apollo Lake.

Signed-off-by: Kan Liang <Kan.liang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: piotr.luc@intel.com
Cc: harry.pan@intel.com
Cc: srinivas.pandruvada@linux.intel.com
Link: http://lkml.kernel.org/r/20170908213449.6224-3-kan.liang@intel.com
2017-09-25 09:36:17 +02:00
Kan Liang
1aaccc40a1 perf/x86/msr: Add missing CPU IDs
Goldmont, Glodmont plus and Xeon Phi have MSR_SMI_COUNT as well.

Signed-off-by: Kan Liang <Kan.liang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: piotr.luc@intel.com
Cc: harry.pan@intel.com
Cc: srinivas.pandruvada@linux.intel.com
Link: http://lkml.kernel.org/r/20170908213449.6224-2-kan.liang@intel.com
2017-09-25 09:36:17 +02:00
Kan Liang
b09c146f8f perf/x86/intel/cstate: Add missing CPU IDs
Skylake server uses the same C-state residency events as Sandy Bridge.

Denverton and Gemini lake use the same C-state residency events as
Apollo Lake.

Signed-off-by: Kan Liang <Kan.liang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: piotr.luc@intel.com
Cc: harry.pan@intel.com
Cc: srinivas.pandruvada@linux.intel.com
Link: http://lkml.kernel.org/r/20170908213449.6224-1-kan.liang@intel.com
2017-09-25 09:36:17 +02:00
Ville Syrjälä
5ac751d9e6 x86: Don't cast away the __user in __get_user_asm_u64()
Don't cast away the __user in __get_user_asm_u64() on x86-32.
Prevents sparse getting upset.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20170912164000.13745-1-ville.syrjala@linux.intel.com
2017-09-25 09:36:16 +02:00
Sean Fu
7d7099433d x86/sysfs: Fix off-by-one error in loop termination
An off-by-one error in loop terminantion conditions in
create_setup_data_nodes() will lead to memory leak when
create_setup_data_node() failed.

Signed-off-by: Sean Fu <fxinrong@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1505090001-1157-1-git-send-email-fxinrong@gmail.com
2017-09-25 09:36:16 +02:00
Laurent Dufour
a3c4fb7c9c x86/mm: Fix fault error path using unsafe vma pointer
commit 7b2d0dbac4 ("x86/mm/pkeys: Pass VMA down in to fault signal
generation code") passes down a vma pointer to the error path, but that is
done once the mmap_sem is released when calling mm_fault_error() from
__do_page_fault().

This is dangerous as the vma structure is no more safe to be used once the
mmap_sem has been released. As only the protection key value is required in
the error processing, we could just pass down this value.

Fix it by passing a pointer to a protection key value down to the fault
signal generation code. The use of a pointer allows to keep the check
generating a warning message in fill_sig_info_pkey() when the vma was not
known. If the pointer is valid, the protection value can be accessed by
deferencing the pointer.

[ tglx: Made *pkey u32 as that's the type which is passed in siginfo ]

Fixes: 7b2d0dbac4 ("x86/mm/pkeys: Pass VMA down in to fault signal generation code")
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1504513935-12742-1-git-send-email-ldufour@linux.vnet.ibm.com
2017-09-25 09:36:15 +02:00
Eric Biggers
d5c8028b47 x86/fpu: Reinitialize FPU registers if restoring FPU state fails
Userspace can change the FPU state of a task using the ptrace() or
rt_sigreturn() system calls.  Because reserved bits in the FPU state can
cause the XRSTOR instruction to fail, the kernel has to carefully
validate that no reserved bits or other invalid values are being set.

Unfortunately, there have been bugs in this validation code.  For
example, we were not checking that the 'xcomp_bv' field in the
xstate_header was 0.  As-is, such bugs are exploitable to read the FPU
registers of other processes on the system.  To do so, an attacker can
create a task, assign to it an invalid FPU state, then spin in a loop
and monitor the values of the FPU registers.  Because the task's FPU
registers are not being restored, sometimes the FPU registers will have
the values from another process.

This is likely to continue to be a problem in the future because the
validation done by the CPU instructions like XRSTOR is not immediately
visible to kernel developers.  Nor will invalid FPU states ever be
encountered during ordinary use --- they will only be seen during
fuzzing or exploits.  There can even be reserved bits outside the
xstate_header which are easy to forget about.  For example, the MXCSR
register contains reserved bits, which were not validated by the
KVM_SET_XSAVE ioctl until commit a575813bfe ("KVM: x86: Fix load
damaged SSEx MXCSR register").

Therefore, mitigate this class of vulnerability by restoring the FPU
registers from init_fpstate if restoring from the task's state fails.

We actually used to do this, but it was (perhaps unwisely) removed by
commit 9ccc27a5d2 ("x86/fpu: Remove error return values from
copy_kernel_to_*regs() functions").  This new patch is also a bit
different.  First, it only clears the registers, not also the bad
in-memory state; this is simpler and makes it easier to make the
mitigation cover all callers of __copy_kernel_to_fpregs().  Second, it
does the register clearing in an exception handler so that no extra
instructions are added to context switches.  In fact, we *remove*
instructions, since previously we were always zeroing the register
containing 'err' even if CONFIG_X86_DEBUG_FPU was disabled.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170922174156.16780-4-ebiggers3@gmail.com
Link: http://lkml.kernel.org/r/20170923130016.21448-27-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-25 09:26:38 +02:00
Eric Biggers
814fb7bb7d x86/fpu: Don't let userspace set bogus xcomp_bv
On x86, userspace can use the ptrace() or rt_sigreturn() system calls to
set a task's extended state (xstate) or "FPU" registers.  ptrace() can
set them for another task using the PTRACE_SETREGSET request with
NT_X86_XSTATE, while rt_sigreturn() can set them for the current task.
In either case, registers can be set to any value, but the kernel
assumes that the XSAVE area itself remains valid in the sense that the
CPU can restore it.

However, in the case where the kernel is using the uncompacted xstate
format (which it does whenever the XSAVES instruction is unavailable),
it was possible for userspace to set the xcomp_bv field in the
xstate_header to an arbitrary value.  However, all bits in that field
are reserved in the uncompacted case, so when switching to a task with
nonzero xcomp_bv, the XRSTOR instruction failed with a #GP fault.  This
caused the WARN_ON_FPU(err) in copy_kernel_to_xregs() to be hit.  In
addition, since the error is otherwise ignored, the FPU registers from
the task previously executing on the CPU were leaked.

Fix the bug by checking that the user-supplied value of xcomp_bv is 0 in
the uncompacted case, and returning an error otherwise.

The reason for validating xcomp_bv rather than simply overwriting it
with 0 is that we want userspace to see an error if it (incorrectly)
provides an XSAVE area in compacted format rather than in uncompacted
format.

Note that as before, in case of error we clear the task's FPU state.
This is perhaps non-ideal, especially for PTRACE_SETREGSET; it might be
better to return an error before changing anything.  But it seems the
"clear on error" behavior is fine for now, and it's a little tricky to
do otherwise because it would mean we couldn't simply copy the full
userspace state into kernel memory in one __copy_from_user().

This bug was found by syzkaller, which hit the above-mentioned
WARN_ON_FPU():

    WARNING: CPU: 1 PID: 0 at ./arch/x86/include/asm/fpu/internal.h:373 __switch_to+0x5b5/0x5d0
    CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.13.0 
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    task: ffff9ba2bc8e42c0 task.stack: ffffa78cc036c000
    RIP: 0010:__switch_to+0x5b5/0x5d0
    RSP: 0000:ffffa78cc08bbb88 EFLAGS: 00010082
    RAX: 00000000fffffffe RBX: ffff9ba2b8bf2180 RCX: 00000000c0000100
    RDX: 00000000ffffffff RSI: 000000005cb10700 RDI: ffff9ba2b8bf36c0
    RBP: ffffa78cc08bbbd0 R08: 00000000929fdf46 R09: 0000000000000001
    R10: 0000000000000000 R11: 0000000000000000 R12: ffff9ba2bc8e42c0
    R13: 0000000000000000 R14: ffff9ba2b8bf3680 R15: ffff9ba2bf5d7b40
    FS:  00007f7e5cb10700(0000) GS:ffff9ba2bf400000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00000000004005cc CR3: 0000000079fd5000 CR4: 00000000001406e0
    Call Trace:
    Code: 84 00 00 00 00 00 e9 11 fd ff ff 0f ff 66 0f 1f 84 00 00 00 00 00 e9 e7 fa ff ff 0f ff 66 0f 1f 84 00 00 00 00 00 e9 c2 fa ff ff <0f> ff 66 0f 1f 84 00 00 00 00 00 e9 d4 fc ff ff 66 66 2e 0f 1f

Here is a C reproducer.  The expected behavior is that the program spin
forever with no output.  However, on a buggy kernel running on a
processor with the "xsave" feature but without the "xsaves" feature
(e.g. Sandy Bridge through Broadwell for Intel), within a second or two
the program reports that the xmm registers were corrupted, i.e. were not
restored correctly.  With CONFIG_X86_DEBUG_FPU=y it also hits the above
kernel warning.

    #define _GNU_SOURCE
    #include <stdbool.h>
    #include <inttypes.h>
    #include <linux/elf.h>
    #include <stdio.h>
    #include <sys/ptrace.h>
    #include <sys/uio.h>
    #include <sys/wait.h>
    #include <unistd.h>

    int main(void)
    {
        int pid = fork();
        uint64_t xstate[512];
        struct iovec iov = { .iov_base = xstate, .iov_len = sizeof(xstate) };

        if (pid == 0) {
            bool tracee = true;
            for (int i = 0; i < sysconf(_SC_NPROCESSORS_ONLN) && tracee; i++)
                tracee = (fork() != 0);
            uint32_t xmm0[4] = { [0 ... 3] = tracee ? 0x00000000 : 0xDEADBEEF };
            asm volatile("   movdqu %0, %%xmm0\n"
                         "   mov %0, %%rbx\n"
                         "1: movdqu %%xmm0, %0\n"
                         "   mov %0, %%rax\n"
                         "   cmp %%rax, %%rbx\n"
                         "   je 1b\n"
                         : "+m" (xmm0) : : "rax", "rbx", "xmm0");
            printf("BUG: xmm registers corrupted!  tracee=%d, xmm0=%08X%08X%08X%08X\n",
                   tracee, xmm0[0], xmm0[1], xmm0[2], xmm0[3]);
        } else {
            usleep(100000);
            ptrace(PTRACE_ATTACH, pid, 0, 0);
            wait(NULL);
            ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov);
            xstate[65] = -1;
            ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov);
            ptrace(PTRACE_CONT, pid, 0, 0);
            wait(NULL);
        }
        return 1;
    }

Note: the program only tests for the bug using the ptrace() system call.
The bug can also be reproduced using the rt_sigreturn() system call, but
only when called from a 32-bit program, since for 64-bit programs the
kernel restores the FPU state from the signal frame by doing XRSTOR
directly from userspace memory (with proper error checking).

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org> [v3.17+]
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Fixes: 0b29643a58 ("x86/xsaves: Change compacted format xsave area header")
Link: http://lkml.kernel.org/r/20170922174156.16780-2-ebiggers3@gmail.com
Link: http://lkml.kernel.org/r/20170923130016.21448-25-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-25 09:26:32 +02:00
Linus Torvalds
a141fd55f2 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Another round of CR3/PCID related fixes (I think this addresses all
  but one of the known problems with PCID support), an objtool fix plus
  a Clang fix that (finally) solves all Clang quirks to build a bootable
  x86 kernel as-is"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asm: Fix inline asm call constraints for Clang
  objtool: Handle another GCC stack pointer adjustment bug
  x86/mm/32: Load a sane CR3 before cpu_init() on secondary CPUs
  x86/mm/32: Move setup_clear_cpu_cap(X86_FEATURE_PCID) earlier
  x86/mm/64: Stop using CR3.PCID == 0 in ASID-aware code
  x86/mm: Factor out CR3-building code
2017-09-24 12:33:58 -07:00
Andi Kleen
03eaec81ac x86/fpu: Turn WARN_ON() in context switch into WARN_ON_FPU()
copy_xregs_to_kernel checks if the alternatives have been already
patched.

This WARN_ON() is always executed in every context switch.

All the other checks in fpu internal.h are WARN_ON_FPU(), but
this one is plain WARN_ON(). I assume it was forgotten to switch it.

So switch it to WARN_ON_FPU() too to avoid some unnecessary code
in the context switch, and a potentially expensive cache line miss for the
global variable.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170329062605.4970-1-andi@firstfloor.org
Link: http://lkml.kernel.org/r/20170923130016.21448-24-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:35 +02:00
kbuild test robot
4f8cef59ba x86/fpu: Fix boolreturn.cocci warnings
arch/x86/kernel/fpu/xstate.c:931:9-10: WARNING: return of 0/1 in function 'xfeatures_mxcsr_quirk' with return type bool

 Return statements in functions returning bool should use true/false instead of 1/0.

Generated by: scripts/coccinelle/misc/boolreturn.cocci

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kbuild-all@01.org
Cc: tipbuild@zytor.com
Link: http://lkml.kernel.org/r/20170306004553.GA25764@lkp-wsm-ep1
Link: http://lkml.kernel.org/r/20170923130016.21448-23-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:35 +02:00
Rik van Riel
0852b37417 x86/fpu: Add FPU state copying quirk to handle XRSTOR failure on Intel Skylake CPUs
On Skylake CPUs I noticed that XRSTOR is unable to deal with states
created by copyout_from_xsaves() if the xstate has only SSE/YMM state, and
no FP state. That is, xfeatures had XFEATURE_MASK_SSE set, but not
XFEATURE_MASK_FP.

The reason is that part of the SSE/YMM state lives in the MXCSR and
MXCSR_FLAGS fields of the FP state.

Ensure that whenever we copy SSE or YMM state around, the MXCSR and
MXCSR_FLAGS fields are also copied around.

Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.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>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170210085445.0f1cc708@annuminas.surriel.com
Link: http://lkml.kernel.org/r/20170923130016.21448-22-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:34 +02:00
Ingo Molnar
99dc26bda2 x86/fpu: Remove struct fpu::fpregs_active
The previous changes paved the way for the removal of the
fpu::fpregs_active state flag - we now only have the
fpu::fpstate_active and fpu::last_cpu fields left.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-21-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:34 +02:00
Ingo Molnar
6cf4edbe05 x86/fpu: Decouple fpregs_activate()/fpregs_deactivate() from fpu->fpregs_active
The fpregs_activate()/fpregs_deactivate() are currently called in such a pattern:

	if (!fpu->fpregs_active)
		fpregs_activate(fpu);

	...

	if (fpu->fpregs_active)
		fpregs_deactivate(fpu);

But note that it's actually safe to call them without checking the flag first.

This further decouples the fpu->fpregs_active flag from actual FPU logic.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-20-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:34 +02:00
Ingo Molnar
f1c8cd0176 x86/fpu: Change fpu->fpregs_active users to fpu->fpstate_active
We want to simplify the FPU state machine by eliminating fpu->fpregs_active,
and we can do that because the two state flags (::fpregs_active and
::fpstate_active) are set essentially together.

The old lazy FPU switching code used to make a distinction - but there's
no lazy switching code anymore, we always switch in an 'eager' fashion.

Do this by first changing all substantial uses of fpu->fpregs_active
to fpu->fpstate_active and adding a few debug checks to double check
our assumption is correct.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-19-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:34 +02:00
Ingo Molnar
b6aa85558d x86/fpu: Split the state handling in fpu__drop()
Prepare fpu__drop() to use fpu->fpregs_active.

There are two distinct usecases for fpu__drop() in this context:
exit_thread() when called for 'current' in exit(), and when called
for another task in fork().

This patch does not change behavior, it only adds a couple of
debug checks and structures the code to make the ->fpregs_active
change more obviously correct.

All the complications will be removed later on.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-18-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:34 +02:00
Ingo Molnar
a10b6a16cd x86/fpu: Make the fpu state change in fpu__clear() scheduler-atomic
Do this temporarily only, to make it easier to change the FPU state machine,
in particular this change couples the fpu->fpregs_active and fpu->fpstate_active
states: they are only set/cleared together (as far as the scheduler sees them).

This will be removed by later patches.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-17-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:33 +02:00
Ingo Molnar
b3a163081c x86/fpu: Simplify fpu->fpregs_active use
The fpregs_active() inline function is pretty pointless - in almost
all the callsites it can be replaced with a direct fpu->fpregs_active
access.

Do so and eliminate the extra layer of obfuscation.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-16-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:33 +02:00
Ingo Molnar
6d7f7da553 x86/fpu: Flip the parameter order in copy_*_to_xstate()
Make it more consistent with regular memcpy() semantics, where the destination
argument comes first.

No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-15-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:33 +02:00
Ingo Molnar
7b9094c688 x86/fpu: Remove 'kbuf' parameter from the copy_user_to_xstate() API
No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-14-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:33 +02:00
Ingo Molnar
59dffa4edb x86/fpu: Remove 'ubuf' parameter from the copy_kernel_to_xstate() API
No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-13-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:33 +02:00
Ingo Molnar
79fecc2b75 x86/fpu: Split copy_user_to_xstate() into copy_kernel_to_xstate() & copy_user_to_xstate()
Similar to:

  x86/fpu: Split copy_xstate_to_user() into copy_xstate_to_kernel() & copy_xstate_to_user()

No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-12-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:32 +02:00
Ingo Molnar
8c0817f4a3 x86/fpu: Simplify __copy_xstate_to_kernel() return values
__copy_xstate_to_kernel() can only return 0 (because kernel copies cannot fail),
simplify the code throughout.

No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-11-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:32 +02:00
Ingo Molnar
6ff15f8db7 x86/fpu: Change 'size_total' parameter to unsigned and standardize the size checks in copy_xstate_to_*()
'size_total' is derived from an unsigned input parameter - and then converted
to 'int' and checked for negative ranges:

	if (size_total < 0 || offset < size_total) {

This conversion and the checks are unnecessary obfuscation, reject overly
large requested copy sizes outright and simplify the underlying code.

Reported-by: Rik van Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.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>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-10-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:32 +02:00
Ingo Molnar
56583c9a14 x86/fpu: Clarify parameter names in the copy_xstate_to_*() methods
Right now there's a confusing mixture of 'offset' and 'size' parameters:

 - __copy_xstate_to_*() input parameter 'end_pos' not not really an offset,
   but the full size of the copy to be performed.

 - input parameter 'count' to copy_xstate_to_*() shadows that of
   __copy_xstate_to_*()'s 'count' parameter name - but the roles
   are different: the first one is the total number of bytes to
   be copied, while the second one is a partial copy size.

To unconfuse all this, use a consistent set of parameter names:

 - 'size' is the partial copy size within a single xstate component
 - 'size_total' is the total copy requested
 - 'offset_start' is the requested starting offset.
 - 'offset' is the offset within an xstate component.

No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-9-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:32 +02:00
Ingo Molnar
8a5b731889 x86/fpu: Remove the 'start_pos' parameter from the __copy_xstate_to_*() functions
'start_pos' is always 0, so remove it and remove the pointless check of 'pos < 0'
which can not ever be true as 'pos' is unsigned ...

No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-8-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:31 +02:00
Ingo Molnar
becb2bb72f x86/fpu: Clean up the parameter definitions of copy_xstate_to_*()
Remove pointless 'const' of non-pointer input parameter.

Remove unnecessary parenthesis that shows uncertainty about arithmetic operator precedence.

Clarify copy_xstate_to_user() description.

No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-7-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:31 +02:00
Ingo Molnar
d7eda6c99c x86/fpu: Clean up parameter order in the copy_xstate_to_*() APIs
Parameter ordering is weird:

  int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, struct xregs_state *xsave);
  int copy_xstate_to_user(unsigned int pos, unsigned int count, void __user *ubuf, struct xregs_state *xsave);

'pos' and 'count', which are attributes of the destination buffer, are listed before the destination
buffer itself ...

List them after the primary arguments instead.

This makes the code more similar to regular memcpy() variant APIs.

No change in functionality.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-6-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:31 +02:00
Ingo Molnar
a69c158fb3 x86/fpu: Remove 'kbuf' parameter from the copy_xstate_to_user() APIs
The 'kbuf' parameter is unused in the _user() side of the API, remove it.

This simplifies the code and makes it easier to think about.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-5-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:31 +02:00
Ingo Molnar
4d981cf2d9 x86/fpu: Remove 'ubuf' parameter from the copy_xstate_to_kernel() APIs
The 'ubuf' parameter is unused in the _kernel() side of the API, remove it.

This simplifies the code and makes it easier to think about.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-4-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:31 +02:00
Ingo Molnar
f0d4f30a7f x86/fpu: Split copy_xstate_to_user() into copy_xstate_to_kernel() & copy_xstate_to_user()
copy_xstate_to_user() is a weird API - in part due to a bad API inherited
from the regset APIs.

But don't propagate that bad API choice into the FPU code - so as a first
step split the API into kernel and user buffer handling routines.

(Also split the xstate_copyout() internal helper.)

The split API is a dumb duplication that should be obviously correct, the
real splitting will be done in the next patch.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-3-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:30 +02:00
Ingo Molnar
656f083116 x86/fpu: Rename copyin_to_xsaves()/copyout_from_xsaves() to copy_user_to_xstate()/copy_xstate_to_user()
The 'copyin/copyout' nomenclature needlessly departs from what the modern FPU code
uses, which is:

 copy_fpregs_to_fpstate()
 copy_fpstate_to_sigframe()
 copy_fregs_to_user()
 copy_fxregs_to_kernel()
 copy_fxregs_to_user()
 copy_kernel_to_fpregs()
 copy_kernel_to_fregs()
 copy_kernel_to_fxregs()
 copy_kernel_to_xregs()
 copy_user_to_fregs()
 copy_user_to_fxregs()
 copy_user_to_xregs()
 copy_xregs_to_kernel()
 copy_xregs_to_user()

I.e. according to this pattern, the following rename should be done:

  copyin_to_xsaves()    -> copy_user_to_xstate()
  copyout_from_xsaves() -> copy_xstate_to_user()

or, if we want to be pedantic, denote that that the user-space format is ptrace:

  copyin_to_xsaves()    -> copy_user_ptrace_to_xstate()
  copyout_from_xsaves() -> copy_xstate_to_user_ptrace()

But I'd suggest the shorter, non-pedantic name.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
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: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-2-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 13:04:30 +02:00
Uros Bizjak
3c52b5c643 x86/asm: Remove unnecessary \n\t in front of CC_SET() from asm templates
There is no need for \n\t in front of CC_SET(), as the macro already includes these two.

Signed-off-by: Uros Bizjak <ubizjak@gmail.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/20170906151808.5634-1-ubizjak@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-24 11:19:01 +02:00
Josh Poimboeuf
f5caf621ee x86/asm: Fix inline asm call constraints for Clang
For inline asm statements which have a CALL instruction, we list the
stack pointer as a constraint to convince GCC to ensure the frame
pointer is set up first:

  static inline void foo()
  {
	register void *__sp asm(_ASM_SP);
	asm("call bar" : "+r" (__sp))
  }

Unfortunately, that pattern causes Clang to corrupt the stack pointer.

The fix is easy: convert the stack pointer register variable to a global
variable.

It should be noted that the end result is different based on the GCC
version.  With GCC 6.4, this patch has exactly the same result as
before:

	defconfig	defconfig-nofp	distro		distro-nofp
 before	9820389		9491555		8816046		8516940
 after	9820389		9491555		8816046		8516940

With GCC 7.2, however, GCC's behavior has changed.  It now changes its
behavior based on the conversion of the register variable to a global.
That somehow convinces it to *always* set up the frame pointer before
inserting *any* inline asm.  (Therefore, listing the variable as an
output constraint is a no-op and is no longer necessary.)  It's a bit
overkill, but the performance impact should be negligible.  And in fact,
there's a nice improvement with frame pointers disabled:

	defconfig	defconfig-nofp	distro		distro-nofp
 before	9796316		9468236		9076191		8790305
 after	9796957		9464267		9076381		8785949

So in summary, while listing the stack pointer as an output constraint
is no longer necessary for newer versions of GCC, it's still needed for
older versions.

Suggested-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3db862e970c432ae823cf515c52b54fec8270e0e.1505942196.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-23 15:06:20 +02:00
Linus Torvalds
0a8abd97dc xen: Fixes for rc2
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Merge tag 'for-linus-4.14b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "A fix for a missing __init annotation and two cleanup patches"

* tag 'for-linus-4.14b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen, arm64: drop dummy lookup_address()
  xen: don't compile pv-specific parts if XEN_PV isn't configured
  xen: x86: mark xen_find_pt_base as __init
2017-09-22 06:40:47 -10:00
Linus Torvalds
7a6d0071d8 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 - Fix compiler warnings in inside-secure
 - Fix LS1021A support in caam
 - Avoid using RBP in x86 crypto code
 - Fix bug in talitos that prevents hashing with algif
 - Fix bugs talitos hashing code that cause incorrect hash result
 - Fix memory freeing path bug in drbg
 - Fix af_alg crash when two SG lists are chained

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: af_alg - update correct dst SGL entry
  crypto: caam - fix LS1021A support on ARMv7 multiplatform kernel
  crypto: inside-secure - fix gcc-4.9 warnings
  crypto: talitos - Don't provide setkey for non hmac hashing algs
  crypto: talitos - fix hashing
  crypto: talitos - fix sha224
  crypto: x86/twofish - Fix RBP usage
  crypto: sha512-avx2 - Fix RBP usage
  crypto: x86/sha256-ssse3 - Fix RBP usage
  crypto: x86/sha256-avx2 - Fix RBP usage
  crypto: x86/sha256-avx - Fix RBP usage
  crypto: x86/sha1-ssse3 - Fix RBP usage
  crypto: x86/sha1-avx2 - Fix RBP usage
  crypto: x86/des3_ede - Fix RBP usage
  crypto: x86/cast6 - Fix RBP usage
  crypto: x86/cast5 - Fix RBP usage
  crypto: x86/camellia - Fix RBP usage
  crypto: x86/blowfish - Fix RBP usage
  crypto: drbg - fix freeing of resources
2017-09-22 06:15:27 -10:00
Ladi Prosek
44889942b6 KVM: nVMX: fix HOST_CR3/HOST_CR4 cache
For nested virt we maintain multiple VMCS that can run on a vCPU. So it is
incorrect to keep vmcs_host_cr3 and vmcs_host_cr4, whose purpose is caching
the value of the rarely changing HOST_CR3 and HOST_CR4 VMCS fields, in
vCPU-wide data structures.

Hyper-V nested on KVM runs into this consistently for me with PCID enabled.
CR3 is updated with a new value, unlikely(cr3 != vmx->host_state.vmcs_host_cr3)
fires, and the currently loaded VMCS is updated. Then we switch from L2 to
L1 and the next exit reverts CR3 to its old value.

Fixes: d6e41f1151 ("x86/mm, KVM: Teach KVM's VMX code that CR3 isn't a constant")
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-22 10:41:32 +02:00
Colin Ian King
51a9a8284e x86/xen: clean up clang build warning
In the case where sizeof(maddr) != sizeof(long) p is initialized and
never read and clang throws a warning on this.  Move declaration of
p to clean up the clang build warning:

warning: Value stored to 'p' during its initialization is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-09-21 12:34:03 -04:00
Josh Poimboeuf
8f182f845d crypto: x86/twofish - Fix RBP usage
Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.

Use R13 instead of RBP.  Both are callee-saved registers, so the
substitution is straightforward.

Reported-by: Eric Biggers <ebiggers@google.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-09-20 17:42:38 +08:00
Josh Poimboeuf
ca04c82376 crypto: sha512-avx2 - Fix RBP usage
Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.

Mix things up a little bit to get rid of the RBP usage, without hurting
performance too much.  Use RDI instead of RBP for the TBL pointer.  That
will clobber CTX, so spill CTX onto the stack and use R12 to read it in
the outer loop.  R12 is used as a non-persistent temporary variable
elsewhere, so it's safe to use.

Also remove the unused y4 variable.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-09-20 17:42:37 +08:00
Josh Poimboeuf
539012dcbd crypto: x86/sha256-ssse3 - Fix RBP usage
Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.

Swap the usages of R12 and RBP.  Use R12 for the TBL register, and use
RBP to store the pre-aligned stack pointer.

Reported-by: Eric Biggers <ebiggers@google.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-09-20 17:42:37 +08:00
Josh Poimboeuf
d3dfbfe2e6 crypto: x86/sha256-avx2 - Fix RBP usage
Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.

There's no need to use RBP as a temporary register for the TBL value,
because it always stores the same value: the address of the K256 table.
Instead just reference the address of K256 directly.

Reported-by: Eric Biggers <ebiggers@google.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-09-20 17:42:36 +08:00
Josh Poimboeuf
673ac6fbc7 crypto: x86/sha256-avx - Fix RBP usage
Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.

Swap the usages of R12 and RBP.  Use R12 for the TBL register, and use
RBP to store the pre-aligned stack pointer.

Reported-by: Eric Biggers <ebiggers@google.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-09-20 17:42:36 +08:00