Commit Graph

22335 Commits

Author SHA1 Message Date
Linus Torvalds
d0b89bd548 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Various low level fixes: fix more fallout from the FPU rework and the
  asm entry code rework, plus an MSI rework fix, and an idle-tracing fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu/math-emu: Fix crash in fork()
  x86/fpu/math-emu: Fix math-emu boot crash
  x86/idle: Restore trace_cpu_idle to mwait_idle() calls
  x86/irq: Build correct vector mapping for multiple MSI interrupts
  Revert "sched/x86_64: Don't save flags on context switch"
2015-08-22 08:15:36 -07:00
Ingo Molnar
827409b2f5 x86/fpu/math-emu: Fix crash in fork()
During later stages of math-emu bootup the following crash triggers:

	 math_emulate: 0060:c100d0a8
	 Kernel panic - not syncing: Math emulation needed in kernel
	 CPU: 0 PID: 1511 Comm: login Not tainted 4.2.0-rc7+ #1012
	 [...]
	 Call Trace:
	  [<c181d50d>] dump_stack+0x41/0x52
	  [<c181c918>] panic+0x77/0x189
	  [<c1003530>] ? math_error+0x140/0x140
	  [<c164c2d7>] math_emulate+0xba7/0xbd0
	  [<c100d0a8>] ? fpu__copy+0x138/0x1c0
	  [<c1109c3c>] ? __alloc_pages_nodemask+0x12c/0x870
	  [<c136ac20>] ? proc_clear_tty+0x40/0x70
	  [<c136ac6e>] ? session_clear_tty+0x1e/0x30
	  [<c1003530>] ? math_error+0x140/0x140
	  [<c1003575>] do_device_not_available+0x45/0x70
	  [<c100d0a8>] ? fpu__copy+0x138/0x1c0
	  [<c18258e6>] error_code+0x5a/0x60
	  [<c1003530>] ? math_error+0x140/0x140
	  [<c100d0a8>] ? fpu__copy+0x138/0x1c0
	  [<c100c205>] arch_dup_task_struct+0x25/0x30
	  [<c1048cea>] copy_process.part.51+0xea/0x1480
	  [<c115a8e5>] ? dput+0x175/0x200
	  [<c136af70>] ? no_tty+0x30/0x30
	  [<c1157242>] ? do_vfs_ioctl+0x322/0x540
	  [<c104a21a>] _do_fork+0xca/0x340
	  [<c1057b06>] ? SyS_rt_sigaction+0x66/0x90
	  [<c104a557>] SyS_clone+0x27/0x30
	  [<c1824a80>] sysenter_do_call+0x12/0x12

The reason is the incorrect assumption in fpu_copy(), that FNSAVE
can be executed from math-emu kernels as well.

Don't try to copy the registers, the soft state will be copied
by fork anyway, so the child task inherits the parent task's
soft math state.

With this fix applied math-emu kernels boot up fine on modern
hardware and the 'no387 nofxsr' boot options.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: 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: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-22 10:23:03 +02:00
Ingo Molnar
5fc960380e x86/fpu/math-emu: Fix math-emu boot crash
On a math-emu bootup the following crash occurs:

	Initializing CPU#0
	------------[ cut here ]------------
	kernel BUG at arch/x86/kernel/traps.c:779!
	invalid opcode: 0000 [#1] SMP
	[...]
	EIP is at do_device_not_available+0xe/0x70
	[...]
	Call Trace:
	 [<c18238e6>] error_code+0x5a/0x60
	 [<c1002bd0>] ? math_error+0x140/0x140
	 [<c100bbd9>] ? fpu__init_cpu+0x59/0xa0
	 [<c1012322>] cpu_init+0x202/0x330
	 [<c104509f>] ? __native_set_fixmap+0x1f/0x30
	 [<c1b56ab0>] trap_init+0x305/0x346
	 [<c1b548af>] start_kernel+0x1a5/0x35d
	 [<c1b542b4>] i386_start_kernel+0x82/0x86

The reason is that in the following commit:

  b1276c48e9 ("x86/fpu: Initialize fpregs in fpu__init_cpu_generic()")

I failed to consider math-emu's limitation that it cannot execute the
FNINIT instruction in kernel mode.

The long term fix might be to allow math-emu to execute (certain) kernel
mode FPU instructions, but for now apply the safe (albeit somewhat ugly)
fix: initialize the emulation state explicitly without trapping out to
the FPU emulator.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: 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: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-22 10:02:04 +02:00
Jisheng Zhang
e43d0189ac x86/idle: Restore trace_cpu_idle to mwait_idle() calls
Commit b253149b84 ("sched/idle/x86: Restore mwait_idle() to fix boot
hangs, to improve power savings and to improve performance") restores
mwait_idle(), but the trace_cpu_idle related calls are missing. This
causes powertop on my old desktop powered by Intel Core2 E6550 to
report zero wakeups and zero events.

Add them back to restore the proper behaviour.

Fixes: b253149b84 ("sched/idle/x86: Restore mwait_idle() to ...")
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Cc: <len.brown@intel.com>
Cc: stable@vger.kernel.org # 4.1
Link: http://lkml.kernel.org/r/1440046479-4262-1-git-send-email-jszhang@marvell.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-20 21:37:45 +02:00
Linus Torvalds
3d3e66ba2c xen: build fix for 4.2-rc7
- Fix i386 build with an (uncommon) configuration
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Merge tag 'for-linus-4.2-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen build fix from David Vrabel:
 "Fix i386 build with an (uncommon) configuration"

* tag 'for-linus-4.2-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: make CONFIG_XEN depend on CONFIG_X86_LOCAL_APIC
2015-08-20 12:21:26 -07:00
David Vrabel
87ffd2b9bb x86/xen: make CONFIG_XEN depend on CONFIG_X86_LOCAL_APIC
Since commit feb44f1f7a (x86/xen:
Provide a "Xen PV" APIC driver to support >255 VCPUs) Xen guests need
a full APIC driver and thus should depend on X86_LOCAL_APIC.

This fixes an i386 build failure with !SMP && !CONFIG_X86_UP_APIC by
disabling Xen support in this configuration.

Users needing Xen support in a non-SMP i386 kernel will need to enable
CONFIG_X86_UP_APIC.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>
2015-08-20 11:45:43 +01:00
Ingo Molnar
b5be5b7fff Merge branch 'x86/asm/urgent' to pick up an entry code fix
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-19 09:05:15 +02:00
Jiang Liu
527f0a91e9 x86/irq: Build correct vector mapping for multiple MSI interrupts
Alex Deucher, Mark Rustad and Alexander Holler reported a regression
with the latest v4.2-rc4 kernel, which breaks some SATA controllers.
With multi-MSI capable SATA controllers, only the first port works,
all other ports time out when executing SATA commands.

This happens because the first argument to assign_irq_vector_policy()
is always the base linux irq number of the multi MSI interrupt block,
so all subsequent vector assignments operate on the base linux irq
number, so all MSI irqs are handled as the first irq number. Therefor
the other MSI irqs of a device are never set up correctly and never
fire.

Add the loop iterator to the base irq number so all vectors are
assigned correctly.

Fixes: b5dc8e6c21 "x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors"
Reported-and-tested-by: Alex Deucher <alexdeucher@gmail.com>
Reported-and-tested-by: Mark Rustad <mrustad@gmail.com>
Reported-and-tested-by: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/1439911228-9880-1-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-18 18:18:55 +02:00
Andy Lutomirski
512255a2ad Revert "sched/x86_64: Don't save flags on context switch"
This reverts commit:

  2c7577a758 ("sched/x86_64: Don't save flags on context switch")

It was a nice speedup.  It's also not quite correct: SYSENTER
enables interrupts too early.

We can re-add this optimization once the SYSENTER code is beaten
into shape, which should happen in 4.3 or 4.4.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # v3.19
Link: http://lkml.kernel.org/r/85f56651f59f76624e80785a8fd3bdfdd089a818.1439838962.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-18 09:39:26 +02:00
Linus Torvalds
01565479e9 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Merge x86 fixes from Ingo Molnar:
 "Two followup fixes related to the previous LDT fix"

Also applied a further FPU emulation fix from Andy Lutomirski to the
branch before actually merging it.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
  x86/ldt: Further fix FPU emulation
  x86/ldt: Correct FPU emulation access to LDT
  x86/ldt: Correct LDT access in single stepping logic
2015-08-16 15:11:25 -07:00
Andy Lutomirski
12e244f4b5 x86/ldt: Further fix FPU emulation
The previous fix confused a selector with a segment prefix.  Fix it.

Compile-tested only.

Cc: stable@vger.kernel.org
Cc: Juergen Gross <jgross@suse.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: 4809146b86 ("x86/ldt: Correct FPU emulation access to LDT")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-16 15:11:05 -07:00
Linus Torvalds
45e38cff4f Just two very small & simple patches.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "Just two very small & simple patches"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST
  KVM: x86: zero IDT limit on entry to SMM
2015-08-14 17:27:52 -07:00
Linus Torvalds
b25c6cee55 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc fixes: PMU driver corner cases, tooling fixes, and an 'AUX'
  (Intel PT) race related core fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/cqm: Do not access cpu_data() from CPU_UP_PREPARE handler
  perf/x86/intel: Fix memory leak on hot-plug allocation fail
  perf: Fix PERF_EVENT_IOC_PERIOD migration race
  perf: Fix double-free of the AUX buffer
  perf: Fix fasync handling on inherited events
  perf tools: Fix test build error when bindir contains double slash
  perf stat: Fix transaction lenght metrics
  perf: Fix running time accounting
2015-08-14 10:57:16 -07:00
Linus Torvalds
cd88ec2317 x86: fix error handling for 32-bit compat out-of-range system call numbers
Commit 3f5159a922 ("x86/asm/entry/32: Update -ENOSYS handling to match
the 64-bit logic") broke the ENOSYS handling for the 32-bit compat case.
The proper error return value was never loaded into %rax, except if
things just happened to go through the audit paths, which ended up
reloading the return value.

This moves the loading or %rax into the normal system call path, just to
make sure the error case triggers it.  It's kind of sad, since it adds a
useless instruction to reload the register to the fast path, but it's
not like that single load from the stack is going to be noticeable.

Reported-by: David Drysdale <drysdale@google.com>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-13 16:19:44 -07:00
Linus Torvalds
6b476e1140 xen: bug fixes for 4.2-rc6
- Revert a fix from 4.2-rc5 that was causing lots of WARNING spam.
 - Fix a memory leak affecting backends in HVM guests.
 - Fix PV domU hang with certain configurations.
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Merge tag 'for-linus-4.2-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen bug fixes from David Vrabel:

 - revert a fix from 4.2-rc5 that was causing lots of WARNING spam.

 - fix a memory leak affecting backends in HVM guests.

 - fix PV domU hang with certain configurations.

* tag 'for-linus-4.2-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/xenbus: Don't leak memory when unmapping the ring on HVM backend
  Revert "xen/events/fifo: Handle linked events when closing a port"
  x86/xen: build "Xen PV" APIC driver for domU as well
2015-08-13 13:36:22 -07:00
Linus Torvalds
ed596cde94 Revert x86 sigcontext cleanups
This reverts commits 9a036b93a3 ("x86/signal/64: Remove 'fs' and 'gs'
from sigcontext") and c6f2062935 ("x86/signal/64: Fix SS handling for
signals delivered to 64-bit programs").

They were cleanups, but they break dosemu by changing the signal return
behavior (and removing 'fs' and 'gs' from the sigcontext struct - while
not actually changing any behavior - causes build problems).

Reported-and-tested-by: Stas Sergeev <stsp@list.ru>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-13 12:42:22 -07:00
Matt Fleming
d7a702f0b1 perf/x86/intel/cqm: Do not access cpu_data() from CPU_UP_PREPARE handler
Tony reports that booting his 144-cpu machine with maxcpus=10 triggers
the following WARN_ON():

[   21.045727] WARNING: CPU: 8 PID: 647 at arch/x86/kernel/cpu/perf_event_intel_cqm.c:1267 intel_cqm_cpu_prepare+0x75/0x90()
[   21.045744] CPU: 8 PID: 647 Comm: systemd-udevd Not tainted 4.2.0-rc4 #1
[   21.045745] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRHSXSD1.86B.0066.R00.1506021730 06/02/2015
[   21.045747]  0000000000000000 0000000082771b09 ffff880856333ba8 ffffffff81669b67
[   21.045748]  0000000000000000 0000000000000000 ffff880856333be8 ffffffff8107b02a
[   21.045750]  ffff88085b789800 ffff88085f68a020 ffffffff819e2470 000000000000000a
[   21.045750] Call Trace:
[   21.045757]  [<ffffffff81669b67>] dump_stack+0x45/0x57
[   21.045759]  [<ffffffff8107b02a>] warn_slowpath_common+0x8a/0xc0
[   21.045761]  [<ffffffff8107b15a>] warn_slowpath_null+0x1a/0x20
[   21.045762]  [<ffffffff81036725>] intel_cqm_cpu_prepare+0x75/0x90
[   21.045764]  [<ffffffff81036872>] intel_cqm_cpu_notifier+0x42/0x160
[   21.045767]  [<ffffffff8109a33d>] notifier_call_chain+0x4d/0x80
[   21.045769]  [<ffffffff8109a44e>] __raw_notifier_call_chain+0xe/0x10
[   21.045770]  [<ffffffff8107b538>] _cpu_up+0xe8/0x190
[   21.045771]  [<ffffffff8107b65a>] cpu_up+0x7a/0xa0
[   21.045774]  [<ffffffff8165e920>] cpu_subsys_online+0x40/0x90
[   21.045777]  [<ffffffff81433b37>] device_online+0x67/0x90
[   21.045778]  [<ffffffff81433bea>] online_store+0x8a/0xa0
[   21.045782]  [<ffffffff81430e78>] dev_attr_store+0x18/0x30
[   21.045785]  [<ffffffff8126b6ba>] sysfs_kf_write+0x3a/0x50
[   21.045786]  [<ffffffff8126ad40>] kernfs_fop_write+0x120/0x170
[   21.045789]  [<ffffffff811f0b77>] __vfs_write+0x37/0x100
[   21.045791]  [<ffffffff811f38b8>] ? __sb_start_write+0x58/0x110
[   21.045795]  [<ffffffff81296d2d>] ? security_file_permission+0x3d/0xc0
[   21.045796]  [<ffffffff811f1279>] vfs_write+0xa9/0x190
[   21.045797]  [<ffffffff811f2075>] SyS_write+0x55/0xc0
[   21.045800]  [<ffffffff81067300>] ? do_page_fault+0x30/0x80
[   21.045804]  [<ffffffff816709ae>] entry_SYSCALL_64_fastpath+0x12/0x71
[   21.045805] ---[ end trace fe228b836d8af405 ]---

The root cause is that CPU_UP_PREPARE is completely the wrong notifier
action from which to access cpu_data(), because smp_store_cpu_info()
won't have been executed by the target CPU at that point, which in turn
means that ->x86_cache_max_rmid and ->x86_cache_occ_scale haven't been
filled out.

Instead let's invoke our handler from CPU_STARTING and rename it
appropriately.

Reported-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vikas Shivappa <vikas.shivappa@intel.com>
Link: http://lkml.kernel.org/r/1438863163-14083-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 11:37:23 +02:00
Peter Zijlstra
dbc72b7a0c perf/x86/intel: Fix memory leak on hot-plug allocation fail
We fail to free the shared_regs allocation if the constraint_list
allocation fails.

Cure this and be more consistent in NULL-ing the pointers after free.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 11:37:22 +02:00
Jason A. Donenfeld
fc5fee86bd x86/xen: build "Xen PV" APIC driver for domU as well
It turns out that a PV domU also requires the "Xen PV" APIC
driver. Otherwise, the flat driver is used and we get stuck in busy
loops that never exit, such as in this stack trace:

(gdb) target remote localhost:9999
Remote debugging using localhost:9999
__xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
56              while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)
(gdb) bt
 #0  __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
 #1  __default_send_IPI_shortcut (shortcut=<optimized out>,
dest=<optimized out>, vector=<optimized out>) at
./arch/x86/include/asm/ipi.h:75
 #2  apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54
 #3  0xffffffff81011336 in arch_irq_work_raise () at
arch/x86/kernel/irq_work.c:47
 #4  0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at
kernel/irq_work.c:100
 #5  0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633
 #6  0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized
out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>,
fmt=<optimized out>, args=<optimized out>)
    at kernel/printk/printk.c:1778
 #7  0xffffffff816010c8 in printk (fmt=<optimized out>) at
kernel/printk/printk.c:1868
 #8  0xffffffffc00013ea in ?? ()
 #9  0x0000000000000000 in ?? ()

Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-10 15:33:10 +01:00
Juergen Gross
4809146b86 x86/ldt: Correct FPU emulation access to LDT
Commit 37868fe113 ("x86/ldt: Make modify_ldt synchronous")
introduced a new struct ldt_struct anchored at mm->context.ldt.

Adapt the x86 fpu emulation code to use that new structure.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: <stable@vger.kernel.org> # On top of: 37868fe113: x86/ldt: Make modify_ldt synchronous
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: billm@melbpc.org.au
Link: http://lkml.kernel.org/r/1438883674-1240-1-git-send-email-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-08 10:20:45 +02:00
Juergen Gross
136d9d83c0 x86/ldt: Correct LDT access in single stepping logic
Commit 37868fe113 ("x86/ldt: Make modify_ldt synchronous")
introduced a new struct ldt_struct anchored at mm->context.ldt.

convert_ip_to_linear() was changed to reflect this, but indexing
into the ldt has to be changed as the pointer is no longer void *.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: <stable@vger.kernel.org> # On top of: 37868fe113: x86/ldt: Make modify_ldt synchronous
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/1438848278-12906-1-git-send-email-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-08 10:20:45 +02:00
Haozhong Zhang
d7add05458 KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST
When kvm_set_msr_common() handles a guest's write to
MSR_IA32_TSC_ADJUST, it will calcuate an adjustment based on the data
written by guest and then use it to adjust TSC offset by calling a
call-back adjust_tsc_offset(). The 3rd parameter of adjust_tsc_offset()
indicates whether the adjustment is in host TSC cycles or in guest TSC
cycles. If SVM TSC scaling is enabled, adjust_tsc_offset()
[i.e. svm_adjust_tsc_offset()] will first scale the adjustment;
otherwise, it will just use the unscaled one. As the MSR write here
comes from the guest, the adjustment is in guest TSC cycles. However,
the current kvm_set_msr_common() uses it as a value in host TSC
cycles (by using true as the 3rd parameter of adjust_tsc_offset()),
which can result in an incorrect adjustment of TSC offset if SVM TSC
scaling is enabled. This patch fixes this problem.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Cc: stable@vger.linux.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-07 13:28:03 +02:00
Paolo Bonzini
18c3626e3d KVM: x86: zero IDT limit on entry to SMM
The recent BlackHat 2015 presentation "The Memory Sinkhole"
mentions that the IDT limit is zeroed on entry to SMM.

This is not documented, and must have changed some time after 2010
(see http://www.ssi.gouv.fr/uploads/IMG/pdf/IT_Defense_2010_final.pdf).
KVM was not doing it, but the fix is easy.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-07 12:46:32 +02:00
Linus Torvalds
4469942bbb Just two very small & simple patches.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "Just two very small & simple patches"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: MTRR: Use default type for non-MTRR-covered gfn before WARN_ON
  KVM: s390: Fix hang VCPU hang/loop regression
2015-08-05 18:50:38 +03:00
Alex Williamson
fc1a8126bf KVM: MTRR: Use default type for non-MTRR-covered gfn before WARN_ON
The patch was munged on commit to re-order these tests resulting in
excessive warnings when trying to do device assignment.  Return to
original ordering: https://lkml.org/lkml/2015/7/15/769

Fixes: 3e5d2fdced ("KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 11:57:57 +02:00
Linus Torvalds
51d2e09b94 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Fallout from the recent NMI fixes: make x86 LDT handling more robust.

  Also some EFI fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ldt: Make modify_ldt synchronous
  x86/xen: Probe target addresses in set_aliased_prot() before the hypercall
  x86/irq: Use the caller provided polarity setting in mp_check_pin_attr()
  efi: Check for NULL efi kernel parameters
  x86/efi: Use all 64 bit of efi_memmap in setup_e820()
2015-08-01 09:16:33 -07:00
Linus Torvalds
7c764cec37 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Must teardown SR-IOV before unregistering netdev in igb driver, from
    Alex Williamson.

 2) Fix ipv6 route unreachable crash in IPVS, from Alex Gartrell.

 3) Default route selection in ipv4 should take the prefix length, table
    ID, and TOS into account, from Julian Anastasov.

 4) sch_plug must have a reset method in order to purge all buffered
    packets when the qdisc is reset, likewise for sch_choke, from WANG
    Cong.

 5) Fix deadlock and races in slave_changelink/br_setport in bridging.
    From Nikolay Aleksandrov.

 6) mlx4 bug fixes (wrong index in port even propagation to VFs,
    overzealous BUG_ON assertion, etc.) from Ido Shamay, Jack
    Morgenstein, and Or Gerlitz.

 7) Turn off klog message about SCTP userspace interface compat that
    makes no sense at all, from Daniel Borkmann.

 8) Fix unbounded restarts of inet frag eviction process, causing NMI
    watchdog soft lockup messages, from Florian Westphal.

 9) Suspend/resume fixes for r8152 from Hayes Wang.

10) Fix busy loop when MSG_WAITALL|MSG_PEEK is used in TCP recv, from
    Sabrina Dubroca.

11) Fix performance regression when removing a lot of routes from the
    ipv4 routing tables, from Alexander Duyck.

12) Fix device leak in AF_PACKET, from Lars Westerhoff.

13) AF_PACKET also has a header length comparison bug due to signedness,
    from Alexander Drozdov.

14) Fix bug in EBPF tail call generation on x86, from Daniel Borkmann.

15) Memory leaks, TSO stats, watchdog timeout and other fixes to
    thunderx driver from Sunil Goutham and Thanneeru Srinivasulu.

16) act_bpf can leak memory when replacing programs, from Daniel
    Borkmann.

17) WOL packet fixes in gianfar driver, from Claudiu Manoil.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (79 commits)
  stmmac: fix missing MODULE_LICENSE in stmmac_platform
  gianfar: Enable device wakeup when appropriate
  gianfar: Fix suspend/resume for wol magic packet
  gianfar: Fix warning when CONFIG_PM off
  act_pedit: check binding before calling tcf_hash_release()
  net: sk_clone_lock() should only do get_net() if the parent is not a kernel socket
  net: sched: fix refcount imbalance in actions
  r8152: reset device when tx timeout
  r8152: add pre_reset and post_reset
  qlcnic: Fix corruption while copying
  act_bpf: fix memory leaks when replacing bpf programs
  net: thunderx: Fix for crash while BGX teardown
  net: thunderx: Add PCI driver shutdown routine
  net: thunderx: Fix crash when changing rss with mutliple traffic flows
  net: thunderx: Set watchdog timeout value
  net: thunderx: Wakeup TXQ only if CQE_TX are processed
  net: thunderx: Suppress alloc_pages() failure warnings
  net: thunderx: Fix TSO packet statistic
  net: thunderx: Fix memory leak when changing queue count
  net: thunderx: Fix RQ_DROP miscalculation
  ...
2015-07-31 17:10:56 -07:00
Andy Lutomirski
37868fe113 x86/ldt: Make modify_ldt synchronous
modify_ldt() has questionable locking and does not synchronize
threads.  Improve it: redesign the locking and synchronize all
threads' LDTs using an IPI on all modifications.

This will dramatically slow down modify_ldt in multithreaded
programs, but there shouldn't be any multithreaded programs that
care about modify_ldt's performance in the first place.

This fixes some fallout from the CVE-2015-5157 fixes.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org <security@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: xen-devel <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/4c6978476782160600471bd865b318db34c7b628.1438291540.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31 10:23:23 +02:00
Andy Lutomirski
aa1acff356 x86/xen: Probe target addresses in set_aliased_prot() before the hypercall
The update_va_mapping hypercall can fail if the VA isn't present
in the guest's page tables.  Under certain loads, this can
result in an OOPS when the target address is in unpopulated vmap
space.

While we're at it, add comments to help explain what's going on.

This isn't a great long-term fix.  This code should probably be
changed to use something like set_memory_ro.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Vrabel <dvrabel@cantab.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org <security@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: xen-devel <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/0b0e55b995cda11e7829f140b833ef932fcabe3a.1438291540.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31 10:23:22 +02:00
Ingo Molnar
1adb9123f9 * Fix an EFI boot issue preventing a Parallels virtual machine from
booting because the upper 32-bits of the EFI memmap pointer were
    being discarded in setup_e820() - Dmitry Skorodumov
 
  * Validate that the "efi" kernel parameter gets used with an argument,
    otherwise we will oops - Ricardo Neri
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Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

 * Fix an EFI boot issue preventing a Parallels virtual machine from
   booting because the upper 32-bits of the EFI memmap pointer were
   being discarded in setup_e820(). (Dmitry Skorodumov)

 * Validate that the "efi" kernel parameter gets used with an argument,
   otherwise we will oops. (Ricardo Neri)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31 09:55:26 +02:00
Jiang Liu
646c4b7549 x86/irq: Use the caller provided polarity setting in mp_check_pin_attr()
Commit d32932d02e ("x86/irq: Convert IOAPIC to use hierarchical
irqdomain interfaces") introduced a regression which causes
malfunction of interrupt lines.

The reason is that the conversion of mp_check_pin_attr() missed to
update the polarity selection of the interrupt pin with the caller
provided setting and instead uses a stale attribute value. That in
turn results in chosing the wrong interrupt flow handler.

Use the caller supplied setting to configure the pin correctly which
also choses the correct interrupt flow handler.

This restores the original behaviour and on the affected
machine/driver (Surface Pro 3, i2c controller) all IOAPIC IRQ
configuration are identical to v4.1.

Fixes: d32932d02e ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces")
Reported-and-tested-by: Matt Fleming <matt@codeblueprint.co.uk>
Reported-and-tested-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Chen Yu <yu.c.chen@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1438242695-23531-1-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-30 21:15:29 +02:00
Ricardo Neri
9115c7589b efi: Check for NULL efi kernel parameters
Even though it is documented how to specifiy efi parameters, it is
possible to cause a kernel panic due to a dereference of a NULL pointer when
parsing such parameters if "efi" alone is given:

PANIC: early exception 0e rip 10:ffffffff812fb361 error 0 cr2 0
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.2.0-rc1+ #450
[ 0.000000]  ffffffff81fe20a9 ffffffff81e03d50 ffffffff8184bb0f 00000000000003f8
[ 0.000000]  0000000000000000 ffffffff81e03e08 ffffffff81f371a1 64656c62616e6520
[ 0.000000]  0000000000000069 000000000000005f 0000000000000000 0000000000000000
[ 0.000000] Call Trace:
[ 0.000000]  [<ffffffff8184bb0f>] dump_stack+0x45/0x57
[ 0.000000]  [<ffffffff81f371a1>] early_idt_handler_common+0x81/0xae
[ 0.000000]  [<ffffffff812fb361>] ? parse_option_str+0x11/0x90
[ 0.000000]  [<ffffffff81f4dd69>] arch_parse_efi_cmdline+0x15/0x42
[ 0.000000]  [<ffffffff81f376e1>] do_early_param+0x50/0x8a
[ 0.000000]  [<ffffffff8106b1b3>] parse_args+0x1e3/0x400
[ 0.000000]  [<ffffffff81f37a43>] parse_early_options+0x24/0x28
[ 0.000000]  [<ffffffff81f37691>] ? loglevel+0x31/0x31
[ 0.000000]  [<ffffffff81f37a78>] parse_early_param+0x31/0x3d
[ 0.000000]  [<ffffffff81f3ae98>] setup_arch+0x2de/0xc08
[ 0.000000]  [<ffffffff8109629a>] ? vprintk_default+0x1a/0x20
[ 0.000000]  [<ffffffff81f37b20>] start_kernel+0x90/0x423
[ 0.000000]  [<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c
[ 0.000000]  [<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef
[ 0.000000] RIP 0xffffffff81ba2efc

This panic is not reproducible with "efi=" as this will result in a non-NULL
zero-length string.

Thus, verify that the pointer to the parameter string is not NULL. This is
consistent with other parameter-parsing functions which check for NULL pointers.

Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-07-30 18:07:11 +01:00
Dmitry Skorodumov
7cc03e4896 x86/efi: Use all 64 bit of efi_memmap in setup_e820()
The efi_info structure stores low 32 bits of memory map
in efi_memmap and high 32 bits in efi_memmap_hi.

While constructing pointer in the setup_e820(), need
to take into account all 64 bit of the pointer.

It is because on 64bit machine the function
efi_get_memory_map() may return full 64bit pointer and before
the patch that pointer was truncated.

The issue is triggered on Parallles virtual machine and
fixed with this patch.

Signed-off-by: Dmitry Skorodumov <sdmitry@parallels.com>
Cc: Denis V. Lunev <den@openvz.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-07-30 18:07:10 +01:00
Daniel Borkmann
2482abb93e ebpf, x86: fix general protection fault when tail call is invoked
With eBPF JIT compiler enabled on x86_64, I was able to reliably trigger
the following general protection fault out of an eBPF program with a simple
tail call, f.e. tracex5 (or a stripped down version of it):

  [  927.097918] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
  [...]
  [  927.100870] task: ffff8801f228b780 ti: ffff880016a64000 task.ti: ffff880016a64000
  [  927.102096] RIP: 0010:[<ffffffffa002440d>]  [<ffffffffa002440d>] 0xffffffffa002440d
  [  927.103390] RSP: 0018:ffff880016a67a68  EFLAGS: 00010006
  [  927.104683] RAX: 5a5a5a5a5a5a5a5a RBX: 0000000000000000 RCX: 0000000000000001
  [  927.105921] RDX: 0000000000000000 RSI: ffff88014e438000 RDI: ffff880016a67e00
  [  927.107137] RBP: ffff880016a67c90 R08: 0000000000000000 R09: 0000000000000001
  [  927.108351] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880016a67e00
  [  927.109567] R13: 0000000000000000 R14: ffff88026500e460 R15: ffff880220a81520
  [  927.110787] FS:  00007fe7d5c1f740(0000) GS:ffff880265000000(0000) knlGS:0000000000000000
  [  927.112021] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [  927.113255] CR2: 0000003e7bbb91a0 CR3: 000000006e04b000 CR4: 00000000001407e0
  [  927.114500] Stack:
  [  927.115737]  ffffc90008cdb000 ffff880016a67e00 ffff88026500e460 ffff880220a81520
  [  927.117005]  0000000100000000 000000000000001b ffff880016a67aa8 ffffffff8106c548
  [  927.118276]  00007ffcdaf22e58 0000000000000000 0000000000000000 ffff880016a67ff0
  [  927.119543] Call Trace:
  [  927.120797]  [<ffffffff8106c548>] ? lookup_address+0x28/0x30
  [  927.122058]  [<ffffffff8113d176>] ? __module_text_address+0x16/0x70
  [  927.123314]  [<ffffffff8117bf0e>] ? is_ftrace_trampoline+0x3e/0x70
  [  927.124562]  [<ffffffff810c1a0f>] ? __kernel_text_address+0x5f/0x80
  [  927.125806]  [<ffffffff8102086f>] ? print_context_stack+0x7f/0xf0
  [  927.127033]  [<ffffffff810f7852>] ? __lock_acquire+0x572/0x2050
  [  927.128254]  [<ffffffff810f7852>] ? __lock_acquire+0x572/0x2050
  [  927.129461]  [<ffffffff8119edfa>] ? trace_call_bpf+0x3a/0x140
  [  927.130654]  [<ffffffff8119ee4a>] trace_call_bpf+0x8a/0x140
  [  927.131837]  [<ffffffff8119edfa>] ? trace_call_bpf+0x3a/0x140
  [  927.133015]  [<ffffffff8119f008>] kprobe_perf_func+0x28/0x220
  [  927.134195]  [<ffffffff811a1668>] kprobe_dispatcher+0x38/0x60
  [  927.135367]  [<ffffffff81174b91>] ? seccomp_phase1+0x1/0x230
  [  927.136523]  [<ffffffff81061400>] kprobe_ftrace_handler+0xf0/0x150
  [  927.137666]  [<ffffffff81174b95>] ? seccomp_phase1+0x5/0x230
  [  927.138802]  [<ffffffff8117950c>] ftrace_ops_recurs_func+0x5c/0xb0
  [  927.139934]  [<ffffffffa022b0d5>] 0xffffffffa022b0d5
  [  927.141066]  [<ffffffff81174b91>] ? seccomp_phase1+0x1/0x230
  [  927.142199]  [<ffffffff81174b95>] seccomp_phase1+0x5/0x230
  [  927.143323]  [<ffffffff8102c0a4>] syscall_trace_enter_phase1+0xc4/0x150
  [  927.144450]  [<ffffffff81174b95>] ? seccomp_phase1+0x5/0x230
  [  927.145572]  [<ffffffff8102c0a4>] ? syscall_trace_enter_phase1+0xc4/0x150
  [  927.146666]  [<ffffffff817f9a9f>] tracesys+0xd/0x44
  [  927.147723] Code: 48 8b 46 10 48 39 d0 76 2c 8b 85 fc fd ff ff 83 f8 20 77 21 83
                       c0 01 89 85 fc fd ff ff 48 8d 44 d6 80 48 8b 00 48 83 f8 00 74
                       0a <48> 8b 40 20 48 83 c0 33 ff e0 48 89 d8 48 8b 9d d8 fd ff
                       ff 4c
  [  927.150046] RIP  [<ffffffffa002440d>] 0xffffffffa002440d

The code section with the instructions that traps points into the eBPF JIT
image of the root program (the one invoking the tail call instruction).

Using bpf_jit_disasm -o on the eBPF root program image:

  [...]
  4e:   mov    -0x204(%rbp),%eax
        8b 85 fc fd ff ff
  54:   cmp    $0x20,%eax               <--- if (tail_call_cnt > MAX_TAIL_CALL_CNT)
        83 f8 20
  57:   ja     0x000000000000007a
        77 21
  59:   add    $0x1,%eax                <--- tail_call_cnt++
        83 c0 01
  5c:   mov    %eax,-0x204(%rbp)
        89 85 fc fd ff ff
  62:   lea    -0x80(%rsi,%rdx,8),%rax  <--- prog = array->prog[index]
        48 8d 44 d6 80
  67:   mov    (%rax),%rax
        48 8b 00
  6a:   cmp    $0x0,%rax                <--- check for NULL
        48 83 f8 00
  6e:   je     0x000000000000007a
        74 0a
  70:   mov    0x20(%rax),%rax          <--- GPF triggered here! fetch of bpf_func
        48 8b 40 20                              [ matches <48> 8b 40 20 ... from above ]
  74:   add    $0x33,%rax               <--- prologue skip of new prog
        48 83 c0 33
  78:   jmpq   *%rax                    <--- jump to new prog insns
        ff e0
  [...]

The problem is that rax has 5a5a5a5a5a5a5a5a, which suggests a tail call
jump to map slot 0 is pointing to a poisoned page. The issue is the following:

lea instruction has a wrong offset, i.e. it should be ...

  lea    0x80(%rsi,%rdx,8),%rax

... but it actually seems to be ...

  lea   -0x80(%rsi,%rdx,8),%rax

... where 0x80 is offsetof(struct bpf_array, prog), thus the offset needs
to be positive instead of negative. Disassembling the interpreter, we btw
similarly do:

  [...]
  c88:  lea     0x80(%rax,%rdx,8),%rax  <--- prog = array->prog[index]
        48 8d 84 d0 80 00 00 00
  c90:  add     $0x1,%r13d
        41 83 c5 01
  c94:  mov     (%rax),%rax
        48 8b 00
  [...]

Now the other interesting fact is that this panic triggers only when things
like CONFIG_LOCKDEP are being used. In that case offsetof(struct bpf_array,
prog) starts at offset 0x80 and in non-CONFIG_LOCKDEP case at offset 0x50.
Reason is that the work_struct inside struct bpf_map grows by 48 bytes in my
case due to the lockdep_map member (which also has CONFIG_LOCK_STAT enabled
members).

Changing the emitter to always use the 4 byte displacement in the lea
instruction fixes the panic on my side. It increases the tail call instruction
emission by 3 more byte, but it should cover us from various combinations
(and perhaps other future increases on related structures).

After patch, disassembly:

  [...]
  9e:   lea    0x80(%rsi,%rdx,8),%rax   <--- CONFIG_LOCKDEP/CONFIG_LOCK_STAT
        48 8d 84 d6 80 00 00 00
  a6:   mov    (%rax),%rax
        48 8b 00
  [...]

  [...]
  9e:   lea    0x50(%rsi,%rdx,8),%rax   <--- No CONFIG_LOCKDEP
        48 8d 84 d6 50 00 00 00
  a6:   mov    (%rax),%rax
        48 8b 00
  [...]

Fixes: b52f00e6a7 ("x86: bpf_jit: implement bpf_tail_call() helper")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 17:02:19 -07:00
Linus Torvalds
2579d019ad Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Thomas Gleixner:
 "A single fix for the intel cqm perf facility to prevent IPIs from
  interrupt context"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/cqm: Return cached counter value from IRQ context
2015-07-26 11:46:32 -07:00
Linus Torvalds
2800348613 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 update contains:

   - the manual revert of the SYSCALL32 changes which caused a
     regression

   - a fix for the MPX vma handling

   - three fixes for the ioremap 'is ram' checks.

   - PAT warning fixes

   - a trivial fix for the size calculation of TLB tracepoints

   - handle old EFI structures gracefully

  This also contains a PAT fix from Jan plus a revert thereof.  Toshi
  explained why the code is correct"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/pat: Revert 'Adjust default caching mode translation tables'
  x86/asm/entry/32: Revert 'Do not use R9 in SYSCALL32' commit
  x86/mm: Fix newly introduced printk format warnings
  mm: Fix bugs in region_is_ram()
  x86/mm: Remove region_is_ram() call from ioremap
  x86/mm: Move warning from __ioremap_check_ram() to the call site
  x86/mm/pat, drivers/media/ivtv: Move the PAT warning and replace WARN() with pr_warn()
  x86/mm/pat, drivers/infiniband/ipath: Replace WARN() with pr_warn()
  x86/mm/pat: Adjust default caching mode translation tables
  x86/fpu: Disable dependent CPU features on "noxsave"
  x86/mpx: Do not set ->vm_ops on MPX VMAs
  x86/mm: Add parenthesis for TLB tracepoint size calculation
  efi: Handle memory error structures produced based on old versions of standard
2015-07-26 11:14:04 -07:00
Thomas Gleixner
1a4e879571 x86/mm/pat: Revert 'Adjust default caching mode translation tables'
Toshi explains:

"No, the default values need to be set to the fallback types,
 i.e. minimal supported mode.  For WC and WT, UC is the fallback type.

 When PAT is disabled, pat_init() does update the tables below to
 enable WT per the default BIOS setup.  However, when PAT is enabled,
 but CPU has PAT -errata, WT falls back to UC per the default values."

Revert: ca1fec58bc 'x86/mm/pat: Adjust default caching mode translation tables'
Requested-by: Toshi Kani <toshi.kani@hp.com>
Cc: Jan Beulich <jbeulich@suse.de>
Link: http://lkml.kernel.org/r/1437577776.3214.252.camel@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-26 10:27:37 +02:00
Matt Fleming
2c534c0da0 perf/x86/intel/cqm: Return cached counter value from IRQ context
Peter reported the following potential crash which I was able to
reproduce with his test program,

[  148.765788] ------------[ cut here ]------------
[  148.765796] WARNING: CPU: 34 PID: 2840 at kernel/smp.c:417 smp_call_function_many+0xb6/0x260()
[  148.765797] Modules linked in:
[  148.765800] CPU: 34 PID: 2840 Comm: perf Not tainted 4.2.0-rc1+ #4
[  148.765803]  ffffffff81cdc398 ffff88085f105950 ffffffff818bdfd5 0000000000000007
[  148.765805]  0000000000000000 ffff88085f105990 ffffffff810e413a 0000000000000000
[  148.765807]  ffffffff82301080 0000000000000022 ffffffff8107f640 ffffffff8107f640
[  148.765809] Call Trace:
[  148.765810]  <NMI>  [<ffffffff818bdfd5>] dump_stack+0x45/0x57
[  148.765818]  [<ffffffff810e413a>] warn_slowpath_common+0x8a/0xc0
[  148.765822]  [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60
[  148.765824]  [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60
[  148.765825]  [<ffffffff810e422a>] warn_slowpath_null+0x1a/0x20
[  148.765827]  [<ffffffff811613f6>] smp_call_function_many+0xb6/0x260
[  148.765829]  [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60
[  148.765831]  [<ffffffff81161748>] on_each_cpu_mask+0x28/0x60
[  148.765832]  [<ffffffff8107f6ef>] intel_cqm_event_count+0x7f/0xe0
[  148.765836]  [<ffffffff811cdd35>] perf_output_read+0x2a5/0x400
[  148.765839]  [<ffffffff811d2e5a>] perf_output_sample+0x31a/0x590
[  148.765840]  [<ffffffff811d333d>] ? perf_prepare_sample+0x26d/0x380
[  148.765841]  [<ffffffff811d3497>] perf_event_output+0x47/0x60
[  148.765843]  [<ffffffff811d36c5>] __perf_event_overflow+0x215/0x240
[  148.765844]  [<ffffffff811d4124>] perf_event_overflow+0x14/0x20
[  148.765847]  [<ffffffff8107e7f4>] intel_pmu_handle_irq+0x1d4/0x440
[  148.765849]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
[  148.765853]  [<ffffffff81219bad>] ? vunmap_page_range+0x19d/0x2f0
[  148.765854]  [<ffffffff81219d11>] ? unmap_kernel_range_noflush+0x11/0x20
[  148.765859]  [<ffffffff814ce6fe>] ? ghes_copy_tofrom_phys+0x11e/0x2a0
[  148.765863]  [<ffffffff8109e5db>] ? native_apic_msr_write+0x2b/0x30
[  148.765865]  [<ffffffff8109e44d>] ? x2apic_send_IPI_self+0x1d/0x20
[  148.765869]  [<ffffffff81065135>] ? arch_irq_work_raise+0x35/0x40
[  148.765872]  [<ffffffff811c8d86>] ? irq_work_queue+0x66/0x80
[  148.765875]  [<ffffffff81075306>] perf_event_nmi_handler+0x26/0x40
[  148.765877]  [<ffffffff81063ed9>] nmi_handle+0x79/0x100
[  148.765879]  [<ffffffff81064422>] default_do_nmi+0x42/0x100
[  148.765880]  [<ffffffff81064563>] do_nmi+0x83/0xb0
[  148.765884]  [<ffffffff818c7c0f>] end_repeat_nmi+0x1e/0x2e
[  148.765886]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
[  148.765888]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
[  148.765890]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
[  148.765891]  <<EOE>>  [<ffffffff8110ab66>] finish_task_switch+0x156/0x210
[  148.765898]  [<ffffffff818c1671>] __schedule+0x341/0x920
[  148.765899]  [<ffffffff818c1c87>] schedule+0x37/0x80
[  148.765903]  [<ffffffff810ae1af>] ? do_page_fault+0x2f/0x80
[  148.765905]  [<ffffffff818c1f4a>] schedule_user+0x1a/0x50
[  148.765907]  [<ffffffff818c666c>] retint_careful+0x14/0x32
[  148.765908] ---[ end trace e33ff2be78e14901 ]---

The CQM task events are not safe to be called from within interrupt
context because they require performing an IPI to read the counter value
on all sockets. And performing IPIs from within IRQ context is a
"no-no".

Make do with the last read counter value currently event in
event->count when we're invoked in this context.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vikas Shivappa <vikas.shivappa@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Will Auld <will.auld@intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1437490509-15373-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-26 10:22:29 +02:00
Denys Vlasenko
c0c3322e98 x86/asm/entry/32: Revert 'Do not use R9 in SYSCALL32' commit
This change reverts most of commit 53e9accf0f 'Do not use R9 in
SYSCALL32'. I don't yet understand how, but code in that commit
sometimes fails to preserve EBP.

See https://bugzilla.kernel.org/show_bug.cgi?id=101061
"Problems while executing 32-bit code on AMD64"

Reported-and-tested-by: Krzysztof A. Sobiecki <sobkas@gmail.com>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Will Drewry <wad@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
CC: x86@kernel.org
Link: http://lkml.kernel.org/r/1437740203-11552-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-24 16:36:00 +02:00
Thomas Gleixner
8a0a5da6d9 x86/mm: Fix newly introduced printk format warnings
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-24 16:35:33 +02:00
Paolo Bonzini
0da029ed7e KVM: x86: rename quirk constants to KVM_X86_QUIRK_*
Make them clearly architecture-dependent; the capability is valid for
all architectures, but the argument is not.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23 08:24:42 +02:00
Xiao Guangrong
fb279950ba KVM: vmx: obey KVM_QUIRK_CD_NW_CLEARED
OVMF depends on WB to boot fast, because it only clears caches after
it has set up MTRRs---which is too late.

Let's do writeback if CR0.CD is set to make it happy, similar to what
SVM is already doing.

Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23 08:23:01 +02:00
Paolo Bonzini
41dbc6bcd9 KVM: x86: introduce kvm_check_has_quirk
The logic of the disabled_quirks field usually results in a double
negation.  Wrap it in a simple function that checks the bit and
negates it.

Based on a patch from Xiao Guangrong.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23 08:22:45 +02:00
Xiao Guangrong
3e5d2fdced KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type
kvm_mtrr_get_guest_memory_type never returns -1 which is implied
in the current code since if @type = -1 (means no MTRR contains the
range), iter.partial_map must be true

Simplify the code to indicate this fact

Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23 08:21:48 +02:00
Xiao Guangrong
10dc331ff5 KVM: MTRR: fix memory type handling if MTRR is completely disabled
Currently code uses default memory type if MTRR is fully disabled,
fix it by using UC instead.

Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23 08:21:33 +02:00
Toshi Kani
9a58eebe1a x86/mm: Remove region_is_ram() call from ioremap
__ioremap_caller() calls region_is_ram() to walk through the
iomem_resource table to check if a target range is in RAM, which was
added to improve the lookup performance over page_is_ram() (commit
906e36c5c7 "x86: use optimized ioresource lookup in ioremap
function"). page_is_ram() was no longer used when this change was
added, though.

__ioremap_caller() then calls walk_system_ram_range(), which had
replaced page_is_ram() to improve the lookup performance (commit
c81c8a1eee "x86, ioremap: Speed up check for RAM pages").

Since both checks walk through the same iomem_resource table for
the same purpose, there is no need to call both functions.

Aside of that walk_system_ram_range() is the only useful check at the
moment because region_is_ram() always returns -1 due to an
implementation bug. That bug in region_is_ram() cannot be fixed
without breaking existing ioremap callers, which rely on the subtle
difference of walk_system_ram_range() versus non page aligned ranges.

Once these offending callers are fixed we can use region_is_ram() and
remove walk_system_ram_range().

[ tglx: Massaged changelog ]

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1437088996-28511-3-git-send-email-toshi.kani@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-22 17:20:34 +02:00
Toshi Kani
1c9cf9b211 x86/mm: Move warning from __ioremap_check_ram() to the call site
__ioremap_check_ram() has a WARN_ONCE() which is emitted when the
given pfn range is not RAM. The warning is bogus in two aspects:

- it never triggers since walk_system_ram_range() only calls
  __ioremap_check_ram() for RAM ranges.

- the warning message is wrong as it says: "ioremap on RAM' after it
  established that the pfn range is not RAM.

Move the WARN_ONCE() to __ioremap_caller(), and update the message to
include the address range so we get an actual warning when something
tries to ioremap system RAM.

[ tglx: Massaged changelog ]

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1437088996-28511-2-git-send-email-toshi.kani@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-22 17:20:33 +02:00
Jan Beulich
ca1fec58bc x86/mm/pat: Adjust default caching mode translation tables
Make WT really mean WT (rather than UC).

I can't see why commit 9cd25aac1f ("x86/mm/pat: Emulate PAT when
it is disabled") didn't make this to match its changes to
pat_init().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Link: http://lkml.kernel.org/r/55ACC3660200007800092E62@mail.emea.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21 08:23:06 +02:00
Jan Beulich
5bc016f1ab x86/fpu: Disable dependent CPU features on "noxsave"
Complete the set of dependent features that need disabling at
once: XSAVEC, AVX-512 and all currently known to the kernel
extensions to it, as well as MPX need to be disabled too.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/55ACC40D0200007800092E6C@mail.emea.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21 08:20:42 +02:00
Kirill A. Shutemov
a896527694 x86/mpx: Do not set ->vm_ops on MPX VMAs
MPX setups private anonymous mapping, but uses vma->vm_ops too.
This can confuse core VM, as it relies on vm->vm_ops to
distinguish file VMAs from anonymous.

As result we will get SIGBUS, because handle_pte_fault() thinks
it's file VMA without vm_ops->fault and it doesn't know how to
handle the situation properly.

Let's fix that by not setting ->vm_ops.

We don't really need ->vm_ops here: MPX VMA can be detected with
VM_MPX flag. And vma_merge() will not merge MPX VMA with non-MPX
VMA, because ->vm_flags won't match.

The only thing left is name of VMA. I'm not sure if it's part of
ABI, or we can just drop it. The patch keep it by providing
arch_vma_name() on x86.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org> # Fixes: 6b7339f4 (mm: avoid setting up anonymous pages into file mapping)
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@sr71.net
Link: http://lkml.kernel.org/r/20150720212958.305CC3E9@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21 07:57:16 +02:00