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Merge tag 'for-linus-4.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
"Xen features and fixes for v4.15-rc1
Apart from several small fixes it contains the following features:
- a series by Joao Martins to add vdso support of the pv clock
interface
- a series by Juergen Gross to add support for Xen pv guests to be
able to run on 5 level paging hosts
- a series by Stefano Stabellini adding the Xen pvcalls frontend
driver using a paravirtualized socket interface"
* tag 'for-linus-4.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (34 commits)
xen/pvcalls: fix potential endless loop in pvcalls-front.c
xen/pvcalls: Add MODULE_LICENSE()
MAINTAINERS: xen, kvm: track pvclock-abi.h changes
x86/xen/time: setup vcpu 0 time info page
x86/xen/time: set pvclock flags on xen_time_init()
x86/pvclock: add setter for pvclock_pvti_cpu0_va
ptp_kvm: probe for kvm guest availability
xen/privcmd: remove unused variable pageidx
xen: select grant interface version
xen: update arch/x86/include/asm/xen/cpuid.h
xen: add grant interface version dependent constants to gnttab_ops
xen: limit grant v2 interface to the v1 functionality
xen: re-introduce support for grant v2 interface
xen: support priv-mapping in an HVM tools domain
xen/pvcalls: remove redundant check for irq >= 0
xen/pvcalls: fix unsigned less than zero error check
xen/time: Return -ENODEV from xen_get_wallclock()
xen/pvcalls-front: mark expected switch fall-through
xen: xenbus_probe_frontend: mark expected switch fall-throughs
xen/time: do not decrease steal time after live migration on xen
...
Right now there is only a pvclock_pvti_cpu0_va() which is defined
on kvmclock since:
commit dac16fba6f
("x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap")
The only user of this interface so far is kvm. This commit adds a
setter function for the pvti page and moves pvclock_pvti_cpu0_va
to pvclock, which is a more generic place to have it; and would
allow other PV clocksources to use it, such as Xen.
While moving pvclock_pvti_cpu0_va into pvclock, rename also this
function to pvclock_get_pvti_cpu0_va (including its call sites)
to be symmetric with the setter (pvclock_set_pvti_cpu0_va).
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
The guest physical memory area holding the struct pvclock_wall_clock and
struct pvclock_vcpu_time_info are shared with the hypervisor. It
periodically updates the contents of the memory.
When SEV is active, the encryption attributes from the shared memory pages
must be cleared so that both hypervisor and guest can access the data.
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: kvm@vger.kernel.org
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lkml.kernel.org/r/20171020143059.3291-18-brijesh.singh@amd.com
kvm does not support setting the RTC, so the correct result is -ENODEV.
Returning -1 will cause sync_cmos_clock to keep trying to set the RTC
every second.
Signed-off-by: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which
will have to be picked up from other headers and .c files.
Create a trivial placeholder <linux/sched/clock.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
200 commits and noteworthy changes for most architectures.
* ARM:
- GICv3 save/restore
- cache flushing fixes
- working MSI injection for GICv3 ITS
- physical timer emulation
* MIPS:
- various improvements under the hood
- support for SMP guests
- a large rewrite of MMU emulation. KVM MIPS can now use MMU notifiers
to support copy-on-write, KSM, idle page tracking, swapping, ballooning
and everything else. KVM_CAP_READONLY_MEM is also supported, so that
writes to some memory regions can be treated as MMIO. The new MMU also
paves the way for hardware virtualization support.
* PPC:
- support for POWER9 using the radix-tree MMU for host and guest
- resizable hashed page table
- bugfixes.
* s390: expose more features to the guest
- more SIMD extensions
- instruction execution protection
- ESOP2
* x86:
- improved hashing in the MMU
- faster PageLRU tracking for Intel CPUs without EPT A/D bits
- some refactoring of nested VMX entry/exit code, preparing for live
migration support of nested hypervisors
- expose yet another AVX512 CPUID bit
- host-to-guest PTP support
- refactoring of interrupt injection, with some optimizations thrown in
and some duct tape removed.
- remove lazy FPU handling
- optimizations of user-mode exits
- optimizations of vcpu_is_preempted() for KVM guests
* generic:
- alternative signaling mechanism that doesn't pound on tsk->sighand->siglock
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"4.11 is going to be a relatively large release for KVM, with a little
over 200 commits and noteworthy changes for most architectures.
ARM:
- GICv3 save/restore
- cache flushing fixes
- working MSI injection for GICv3 ITS
- physical timer emulation
MIPS:
- various improvements under the hood
- support for SMP guests
- a large rewrite of MMU emulation. KVM MIPS can now use MMU
notifiers to support copy-on-write, KSM, idle page tracking,
swapping, ballooning and everything else. KVM_CAP_READONLY_MEM is
also supported, so that writes to some memory regions can be
treated as MMIO. The new MMU also paves the way for hardware
virtualization support.
PPC:
- support for POWER9 using the radix-tree MMU for host and guest
- resizable hashed page table
- bugfixes.
s390:
- expose more features to the guest
- more SIMD extensions
- instruction execution protection
- ESOP2
x86:
- improved hashing in the MMU
- faster PageLRU tracking for Intel CPUs without EPT A/D bits
- some refactoring of nested VMX entry/exit code, preparing for live
migration support of nested hypervisors
- expose yet another AVX512 CPUID bit
- host-to-guest PTP support
- refactoring of interrupt injection, with some optimizations thrown
in and some duct tape removed.
- remove lazy FPU handling
- optimizations of user-mode exits
- optimizations of vcpu_is_preempted() for KVM guests
generic:
- alternative signaling mechanism that doesn't pound on
tsk->sighand->siglock"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (195 commits)
x86/kvm: Provide optimized version of vcpu_is_preempted() for x86-64
x86/paravirt: Change vcp_is_preempted() arg type to long
KVM: VMX: use correct vmcs_read/write for guest segment selector/base
x86/kvm/vmx: Defer TR reload after VM exit
x86/asm/64: Drop __cacheline_aligned from struct x86_hw_tss
x86/kvm/vmx: Simplify segment_base()
x86/kvm/vmx: Get rid of segment_base() on 64-bit kernels
x86/kvm/vmx: Don't fetch the TSS base from the GDT
x86/asm: Define the kernel TSS limit in a macro
kvm: fix page struct leak in handle_vmon
KVM: PPC: Book3S HV: Disable HPT resizing on POWER9 for now
KVM: Return an error code only as a constant in kvm_get_dirty_log()
KVM: Return an error code only as a constant in kvm_get_dirty_log_protect()
KVM: Return directly after a failed copy_from_user() in kvm_vm_compat_ioctl()
KVM: x86: remove code for lazy FPU handling
KVM: race-free exit from KVM_RUN without POSIX signals
KVM: PPC: Book3S HV: Turn "KVM guest htab" message into a debug message
KVM: PPC: Book3S PR: Ratelimit copy data failure error messages
KVM: Support vCPU-based gfn->hva cache
KVM: use separate generations for each address space
...
Mike reported that he could trigger the WARN_ON_ONCE() in
set_sched_clock_stable() using hotplug.
This exposed a fundamental problem with the interface, we should never
mark the TSC stable if we ever find it to be unstable. Therefore
set_sched_clock_stable() is a broken interface.
The reason it existed is that not having it is a pain, it means all
relevant architecture code needs to call clear_sched_clock_stable()
where appropriate.
Of the three architectures that select HAVE_UNSTABLE_SCHED_CLOCK ia64
and parisc are trivial in that they never called
set_sched_clock_stable(), so add an unconditional call to
clear_sched_clock_stable() to them.
For x86 the story is a lot more involved, and what this patch tries to
do is ensure we preserve the status quo. So even is Cyrix or Transmeta
have usable TSC they never called set_sched_clock_stable() so they now
get an explicit mark unstable.
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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>
Fixes: 9881b024b7 ("sched/clock: Delay switching sched_clock to stable")
Link: http://lkml.kernel.org/r/20170119133633.GB6536@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is no point in having an extra type for extra confusion. u64 is
unambiguous.
Conversion was done with the following coccinelle script:
@rem@
@@
-typedef u64 cycle_t;
@fix@
typedef cycle_t;
@@
-cycle_t
+u64
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
When booting a kvm guest on AMD with the latest kernel the following
messages are displayed in the boot log:
tsc: Unable to calibrate against PIT
tsc: HPET/PMTIMER calibration failed
aa297292d7 ("x86/tsc: Enumerate SKL cpu_khz and tsc_khz via CPUID")
introduced a change to account for a difference in cpu and tsc frequencies for
Intel SKL processors. Before this change the native tsc set
x86_platform.calibrate_tsc to native_calibrate_tsc() which is a hardware
calibration of the tsc, and in tsc_init() executed
tsc_khz = x86_platform.calibrate_tsc();
cpu_khz = tsc_khz;
The kvm code changed x86_platform.calibrate_tsc to kvm_get_tsc_khz() and
executed the same tsc_init() function. This meant that KVM guests did not
execute the native hardware calibration function.
After aa297292d7, there are separate native calibrations for cpu_khz and
tsc_khz. The code sets x86_platform.calibrate_tsc to native_calibrate_tsc()
which is now an Intel specific calibration function, and
x86_platform.calibrate_cpu to native_calibrate_cpu() which is the "old"
native_calibrate_tsc() function (ie, the native hardware calibration
function).
tsc_init() now does
cpu_khz = x86_platform.calibrate_cpu();
tsc_khz = x86_platform.calibrate_tsc();
if (tsc_khz == 0)
tsc_khz = cpu_khz;
else if (abs(cpu_khz - tsc_khz) * 10 > tsc_khz)
cpu_khz = tsc_khz;
The kvm code should not call the hardware initialization in
native_calibrate_cpu(), as it isn't applicable for kvm and it didn't do that
prior to aa297292d7.
This patch resolves this issue by setting x86_platform.calibrate_cpu to
kvm_get_tsc_khz().
v2: I had originally set x86_platform.calibrate_cpu to
cpu_khz_from_cpuid(), however, pbonzini pointed out that the CPUID leaf
in that function is not available in KVM. I have changed the function
pointer to kvm_get_tsc_khz().
Fixes: aa297292d7 ("x86/tsc: Enumerate SKL cpu_khz and tsc_khz via CPUID")
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Len Brown <len.brown@intel.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Guided by grsecurity's analogous __read_only markings in arch/x86,
this applies several uses of __ro_after_init to structures that are
only updated during __init, and const for some structures that are
never updated. Additionally extends __init markings to some functions
that are only used during __init, and cleans up some missing C99 style
static initializers.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Brown <david.brown@linaro.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20160808232906.GA29731@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Newer KVM won't be exposing PVCLOCK_COUNTS_FROM_ZERO anymore.
The purpose of that flags was to start counting system time from 0 when
the KVM clock has been initialized.
We can achieve the same by selecting one read as the initial point.
A simple subtraction will work unless the KVM clock count overflows
earlier (has smaller width) than scheduler's cycle count. We should be
safe till x86_128.
Because PVCLOCK_COUNTS_FROM_ZERO was enabled only on new hypervisors,
setting sched clock as stable based on PVCLOCK_TSC_STABLE_BIT might
regress on older ones.
I presume we don't need to change kvm_clock_read instead of introducing
kvm_sched_clock_read. A problem could arise in case sched_clock is
expected to return the same value as get_cycles, but we should have
merged those clocks in that case.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are two kexec load syscalls, kexec_load another and kexec_file_load.
kexec_file_load has been splited as kernel/kexec_file.c. In this patch I
split kexec_load syscall code to kernel/kexec.c.
And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.
The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled. But kexec-tools use
kexec_load syscall can bypass the checking.
Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel. KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.
Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig. Also updated general kernel code with to
kexec_load syscall.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Petr Tesarik <ptesarik@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If you try to enable NOHZ_FULL on a guest today, you'll get
the following error when the guest tries to deactivate the
scheduler tick:
WARNING: CPU: 3 PID: 2182 at kernel/time/tick-sched.c:192 can_stop_full_tick+0xb9/0x290()
NO_HZ FULL will not work with unstable sched clock
CPU: 3 PID: 2182 Comm: kworker/3:1 Not tainted 4.0.0-10545-gb9bb6fb #204
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: events flush_to_ldisc
ffffffff8162a0c7 ffff88011f583e88 ffffffff814e6ba0 0000000000000002
ffff88011f583ed8 ffff88011f583ec8 ffffffff8104d095 ffff88011f583eb8
0000000000000000 0000000000000003 0000000000000001 0000000000000001
Call Trace:
<IRQ> [<ffffffff814e6ba0>] dump_stack+0x4f/0x7b
[<ffffffff8104d095>] warn_slowpath_common+0x85/0xc0
[<ffffffff8104d146>] warn_slowpath_fmt+0x46/0x50
[<ffffffff810bd2a9>] can_stop_full_tick+0xb9/0x290
[<ffffffff810bd9ed>] tick_nohz_irq_exit+0x8d/0xb0
[<ffffffff810511c5>] irq_exit+0xc5/0x130
[<ffffffff814f180a>] smp_apic_timer_interrupt+0x4a/0x60
[<ffffffff814eff5e>] apic_timer_interrupt+0x6e/0x80
<EOI> [<ffffffff814ee5d1>] ? _raw_spin_unlock_irqrestore+0x31/0x60
[<ffffffff8108bbc8>] __wake_up+0x48/0x60
[<ffffffff8134836c>] n_tty_receive_buf_common+0x49c/0xba0
[<ffffffff8134a6bf>] ? tty_ldisc_ref+0x1f/0x70
[<ffffffff81348a84>] n_tty_receive_buf2+0x14/0x20
[<ffffffff8134b390>] flush_to_ldisc+0xe0/0x120
[<ffffffff81064d05>] process_one_work+0x1d5/0x540
[<ffffffff81064c81>] ? process_one_work+0x151/0x540
[<ffffffff81065191>] worker_thread+0x121/0x470
[<ffffffff81065070>] ? process_one_work+0x540/0x540
[<ffffffff8106b4df>] kthread+0xef/0x110
[<ffffffff8106b3f0>] ? __kthread_parkme+0xa0/0xa0
[<ffffffff814ef4f2>] ret_from_fork+0x42/0x70
[<ffffffff8106b3f0>] ? __kthread_parkme+0xa0/0xa0
---[ end trace 06e3507544a38866 ]---
However, it turns out that kvmclock does provide a stable
sched_clock callback. So, let the scheduler know this which
in turn makes NOHZ_FULL work in the guest.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This reverts commit ff7bbb9c6a.
Sasha Levin is seeing odd jump in time values during boot of a KVM guest:
[...]
[ 0.000000] tsc: Detected 2260.998 MHz processor
[3376355.247558] Calibrating delay loop (skipped) preset value..
[...]
and bisected them to this commit.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If you try to enable NOHZ_FULL on a guest today, you'll get
the following error when the guest tries to deactivate the
scheduler tick:
WARNING: CPU: 3 PID: 2182 at kernel/time/tick-sched.c:192 can_stop_full_tick+0xb9/0x290()
NO_HZ FULL will not work with unstable sched clock
CPU: 3 PID: 2182 Comm: kworker/3:1 Not tainted 4.0.0-10545-gb9bb6fb #204
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: events flush_to_ldisc
ffffffff8162a0c7 ffff88011f583e88 ffffffff814e6ba0 0000000000000002
ffff88011f583ed8 ffff88011f583ec8 ffffffff8104d095 ffff88011f583eb8
0000000000000000 0000000000000003 0000000000000001 0000000000000001
Call Trace:
<IRQ> [<ffffffff814e6ba0>] dump_stack+0x4f/0x7b
[<ffffffff8104d095>] warn_slowpath_common+0x85/0xc0
[<ffffffff8104d146>] warn_slowpath_fmt+0x46/0x50
[<ffffffff810bd2a9>] can_stop_full_tick+0xb9/0x290
[<ffffffff810bd9ed>] tick_nohz_irq_exit+0x8d/0xb0
[<ffffffff810511c5>] irq_exit+0xc5/0x130
[<ffffffff814f180a>] smp_apic_timer_interrupt+0x4a/0x60
[<ffffffff814eff5e>] apic_timer_interrupt+0x6e/0x80
<EOI> [<ffffffff814ee5d1>] ? _raw_spin_unlock_irqrestore+0x31/0x60
[<ffffffff8108bbc8>] __wake_up+0x48/0x60
[<ffffffff8134836c>] n_tty_receive_buf_common+0x49c/0xba0
[<ffffffff8134a6bf>] ? tty_ldisc_ref+0x1f/0x70
[<ffffffff81348a84>] n_tty_receive_buf2+0x14/0x20
[<ffffffff8134b390>] flush_to_ldisc+0xe0/0x120
[<ffffffff81064d05>] process_one_work+0x1d5/0x540
[<ffffffff81064c81>] ? process_one_work+0x151/0x540
[<ffffffff81065191>] worker_thread+0x121/0x470
[<ffffffff81065070>] ? process_one_work+0x540/0x540
[<ffffffff8106b4df>] kthread+0xef/0x110
[<ffffffff8106b3f0>] ? __kthread_parkme+0xa0/0xa0
[<ffffffff814ef4f2>] ret_from_fork+0x42/0x70
[<ffffffff8106b3f0>] ? __kthread_parkme+0xa0/0xa0
---[ end trace 06e3507544a38866 ]---
However, it turns out that kvmclock does provide a stable
sched_clock callback. So, let the scheduler know this which
in turn makes NOHZ_FULL work in the guest.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
paravirt_enabled has the following effects:
- Disables the F00F bug workaround warning. There is no F00F bug
workaround any more because Linux's standard IDT handling already
works around the F00F bug, but the warning still exists. This
is only cosmetic, and, in any event, there is no such thing as
KVM on a CPU with the F00F bug.
- Disables 32-bit APM BIOS detection. On a KVM paravirt system,
there should be no APM BIOS anyway.
- Disables tboot. I think that the tboot code should check the
CPUID hypervisor bit directly if it matters.
- paravirt_enabled disables espfix32. espfix32 should *not* be
disabled under KVM paravirt.
The last point is the purpose of this patch. It fixes a leak of the
high 16 bits of the kernel stack address on 32-bit KVM paravirt
guests. Fixes CVE-2014-8134.
Cc: stable@vger.kernel.org
Suggested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We can use get_cpu() and put_cpu() to replace
preempt_disable()/cpu = smp_processor_id() and
preempt_enable() for slightly better code.
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These days hv_clock allocation is memblock based (i.e. the percpu
allocator is not involved), which means that the physical address
of each of the per-cpu hv_clock areas is guaranteed to remain
unchanged through all its lifetime and we do not need to update
its location after CPU bring-up.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Implement reset of kernel watchdogs at pvclock read time. This avoids
adding special code to every watchdog.
This is possible for watchdogs which measure time based on sched_clock() or
ktime_get() variants.
Suggested by Don Zickus.
Acked-by: Don Zickus <dzickus@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings. In any case, they are temporary and harmless.
This removes all the arch/x86 uses of the __cpuinit macros from
all C files. x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/core
Frederic sayed: "Most of these patches have been hanging around for
several month now, in -mmotm for a significant chunk. They already
missed a few releases."
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
kernel might hung in pvclock_clocksource_read() due to
uninitialized memory might contain odd version value in
following cycle:
do {
version = __pvclock_read_cycles(src, &ret, &flags);
} while ((src->version & 1) || version != src->version);
if secondary kvmclock is accessed before it's registered with kvm.
Clear garbage in pvclock shared memory area right after it's
allocated to avoid this issue.
Ref: https://bugzilla.kernel.org/show_bug.cgi?id=59521
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
[See BZ for analysis. We may want a different fix for 3.11, but
this is the safest for now - Paolo]
Cc: <stable@vger.kernel.org> # 3.8
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
All the virtualized platforms (KVM, lguest and Xen) have persistent
wallclocks that have more than one second of precision.
read_persistent_wallclock() and update_persistent_wallclock() allow
for nanosecond precision but their implementation on x86 with
x86_platform.get/set_wallclock() only allows for one second precision.
This means guests may see a wallclock time that is off by up to 1
second.
Make set_wallclock() and get_wallclock() take a struct timespec
parameter (which allows for nanosecond precision) so KVM and Xen
guests may start with a more accurate wallclock time and a Xen dom0
can maintain a more accurate wallclock for guests.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
* master: (15791 commits)
Linux 3.9-rc1
btrfs/raid56: Add missing #include <linux/vmalloc.h>
fix compat_sys_rt_sigprocmask()
SUNRPC: One line comment fix
ext4: enable quotas before orphan cleanup
ext4: don't allow quota mount options when quota feature enabled
ext4: fix a warning from sparse check for ext4_dir_llseek
ext4: convert number of blocks to clusters properly
ext4: fix possible memory leak in ext4_remount()
jbd2: fix ERR_PTR dereference in jbd2__journal_start
metag: Provide dma_get_sgtable()
metag: prom.h: remove declaration of metag_dt_memblock_reserve()
metag: copy devicetree to non-init memory
metag: cleanup metag_ksyms.c includes
metag: move mm/init.c exports out of metag_ksyms.c
metag: move usercopy.c exports out of metag_ksyms.c
metag: move setup.c exports out of metag_ksyms.c
metag: move kick.c exports out of metag_ksyms.c
metag: move traps.c exports out of metag_ksyms.c
metag: move irq enable out of irqflags.h on SMP
...
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Conflicts:
arch/x86/kernel/kvmclock.c
This fixes boot lockups with "no-kvmclock", when the host is not
exposing this particular feature (QEMU: -cpu ...,-kvmclock) or when
the kvmclock initialization failed for whatever reason.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
To match whats mapped via vsyscalls to userspace.
Reported-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
In short, it is illegal to call __pa() on an address holding
a percpu variable. This replaces those __pa() calls with
slow_virt_to_phys(). All of the cases in this patch are
in boot time (or CPU hotplug time at worst) code, so the
slow pagetable walking in slow_virt_to_phys() is not expected
to have a performance impact.
The times when this actually matters are pretty obscure
(certain 32-bit NUMA systems), but it _does_ happen. It is
important to keep KVM guests working on these systems because
the real hardware is getting harder and harder to find.
This bug manifested first by me seeing a plain hang at boot
after this message:
CPU 0 irqstacks, hard=f3018000 soft=f301a000
or, sometimes, it would actually make it out to the console:
[ 0.000000] BUG: unable to handle kernel paging request at ffffffff
I eventually traced it down to the KVM async pagefault code.
This can be worked around by disabling that code either at
compile-time, or on the kernel command-line.
The kvm async pagefault code was injecting page faults in
to the guest which the guest misinterpreted because its
"reason" was not being properly sent from the host.
The guest passes a physical address of an per-cpu async page
fault structure via an MSR to the host. Since __pa() is
broken on percpu data, the physical address it sent was
bascially bogus and the host went scribbling on random data.
The guest never saw the real reason for the page fault (it
was injected by the host), assumed that the kernel had taken
a _real_ page fault, and panic()'d. The behavior varied,
though, depending on what got corrupted by the bad write.
Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20130122212435.4905663F@kernel.stglabs.ibm.com
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Hook into generic pvclock vsyscall code, with the aim to
allow userspace to have visibility into pvclock data.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
We want to expose the pvclock shared memory areas, which
the hypervisor periodically updates, to userspace.
For a linear mapping from userspace, it is necessary that
entire page sized regions are used for array of pvclock
structures.
There is no such guarantee with per cpu areas, therefore move
to memblock_alloc based allocation.
Acked-by: Glauber Costa <glommer@parallels.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
CPU offline path calls the hrtimer interrupt handler with interrupts
disabled, without touching preempt_count, triggering this warning.
Remove the warning since it is supposed to be used from hrtimer
interrupt context only.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
check_and_clear_guest_paused does not need to be exported as it isn't used
by any modules, remove the export.
Signed-off-by: Eric B Munson <emunson@mgebm.net>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
When a host stops or suspends a VM it will set a flag to show this. The
watchdog will use these functions to determine if a softlockup is real, or the
result of a suspended VM.
Signed-off-by: Eric B Munson <emunson@mgebm.net>
asm-generic changes Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Upon resume from hibernation, CPU 0's hvclock area contains the old
values for system_time and tsc_timestamp. It is necessary for the
hypervisor to update these values with uptodate ones before the CPU uses
them.
Abstract TSC's save/restore sched_clock_state functions and use
restore_state to write to KVM_SYSTEM_TIME MSR, forcing an update.
Also move restore_sched_clock_state before __restore_processor_state,
since the later calls CONFIG_LOCK_STAT's lockstat_clock (also for TSC).
Thanks to Igor Mammedov for tracking it down.
Fixes suspend-to-disk with kvmclock.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
When kvm guest uses kvmclock, it may hang on vcpu hot-plug.
This is caused by an overflow in pvclock_get_nsec_offset,
u64 delta = tsc - shadow->tsc_timestamp;
which in turn is caused by an undefined values from percpu
hv_clock that hasn't been initialized yet.
Uninitialized clock on being booted cpu is accessed from
start_secondary
-> smp_callin
-> smp_store_cpu_info
-> identify_secondary_cpu
-> mtrr_ap_init
-> mtrr_restore
-> stop_machine_from_inactive_cpu
-> queue_stop_cpus_work
...
-> sched_clock
-> kvm_clock_read
which is well before x86_cpuinit.setup_percpu_clockev call in
start_secondary, where percpu clock is initialized.
This patch introduces a hook that allows to setup/initialize
per_cpu clock early and avoid overflow due to reading
- undefined values
- old values if cpu was offlined and then onlined again
Another possible early user of this clock source is ftrace that
accesses it to get timestamps for ring buffer entries. So if
mtrr_ap_init is moved from identify_secondary_cpu to past
x86_cpuinit.setup_percpu_clockev in start_secondary, ftrace
may cause the same overflow/hang on cpu hot-plug anyway.
More complete description of the problem:
https://lkml.org/lkml/2012/2/2/101
Credits to Marcelo Tosatti <mtosatti@redhat.com> for hook idea.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Prevent tracing of preempt_disable() in get_cpu_var() in
kvm_clock_read(). When CONFIG_DEBUG_PREEMPT is enabled,
preempt_disable/enable() are traced and this causes the function_graph
tracer to go into an infinite recursion. By open coding the
preempt_disable() around the get_cpu_var(), we can use the notrace
version which prevents preempt_disable/enable() from being traced and
prevents the recursion.
Based on a similar patch for Xen from Jeremy Fitzhardinge.
Tested-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch implements the kvm bits of the steal time infrastructure.
The most important part of it, is the steal time clock. It is an
continuous clock that shows the accumulated amount of steal time
since vcpu creation. It is supposed to survive cpu offlining/onlining.
[marcelo: fix build with CONFIG_KVM_GUEST=n]
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Eric B Munson <emunson@mgebm.net>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Avi Kivity <avi@redhat.com>
CC: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This converts the remaining x86 clocksources to use
clocksource_register_hz/khz.
CC: jacob.jun.pan@intel.com
CC: Glauber Costa <glommer@redhat.com>
CC: Dimitri Sivanich <sivanich@sgi.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Jeremy Fitzhardinge <jeremy@xensource.com>
CC: Chris McDermott <lcm@us.ibm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Async PF also needs to hook into smp_prepare_boot_cpu so move the hook
into generic code.
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Fix a hang during SMP kernel boot on KVM that showed up
after commit 489fb490db
(2.6.35) and 59aab522154a2f17b25335b63c1cf68a51fb6ae0
(2.6.34.1). The problem only occurs when
CONFIG_PRINTK_TIME is set.
KVM-Stable-Tag.
Signed-off-by: Arjan Koers <0h61vkll2ly8@xutrox.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If the HV told us we can fully trust the TSC, skip any
correction
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
We now added a new set of clock-related msrs in replacement of the old
ones. In theory, we could just try to use them and get a return value
indicating they do not exist, due to our use of kvm_write_msr_save.
However, kvm clock registration happens very early, and if we ever
try to write to a non-existant MSR, we raise a lethal #GP, since our
idt handlers are not in place yet.
So this patch tests for a cpuid feature exported by the host to
decide which set of msrs are supported.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (38 commits)
x86: Move get/set_wallclock to x86_platform_ops
x86: platform: Fix section annotations
x86: apic namespace cleanup
x86: Distangle ioapic and i8259
x86: Add Moorestown early detection
x86: Add hardware_subarch ID for Moorestown
x86: Add early platform detection
x86: Move tsc_init to late_time_init
x86: Move tsc_calibration to x86_init_ops
x86: Replace the now identical time_32/64.c by time.c
x86: time_32/64.c unify profile_pc
x86: Move calibrate_cpu to tsc.c
x86: Make timer setup and global variables the same in time_32/64.c
x86: Remove mca bus ifdef from timer interrupt
x86: Simplify timer_ack magic in time_32.c
x86: Prepare unification of time_32/64.c
x86: Remove do_timer hook
x86: Add timer_init to x86_init_ops
x86: Move percpu clockevents setup to x86_init_ops
x86: Move xen_post_allocator_init into xen_pagetable_setup_done
...
Fix up conflicts in arch/x86/include/asm/io_apic.h
get/set_wallclock() have already a set of platform dependent
implementations (default, EFI, paravirt). MRST will add another
variant.
Moving them to platform ops simplifies the existing code and minimizes
the effort to integrate new variants.
Signed-off-by: Feng Tang <feng.tang@intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The use of __pa() to calculate the address of a C-visible symbol
is wrong, and can lead to unpredictable results. See arch/x86/include/asm/page.h
for details.
It should be replaced with __pa_symbol(), that does the correct math here,
by taking relocations into account. This ensures the correct wallclock data
structure physical address is passed to the hypervisor.
Cc: stable@kernel.org
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
