Certain clocks (such as TSC) in older 2.6 guests overaccount for lost
ticks, causing severe time drift. Interrupt reinjection magnifies the
problem.
Provide an option to disable it.
[avi: allow room for expansion in case we want to disable reinjection
of other timers]
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Since we advertise MSR_VM_HSAVE_PA, userspace will attempt to read it
even on Intel. Implement fake support for this MSR to avoid the
warnings.
Signed-off-by: Avi Kivity <avi@redhat.com>
vmap() on guest pages hides those pages from the Linux mm for an extended
(userspace determined) amount of time. Get rid of it.
Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit change the name of emulator_read_std into kvm_read_guest_virt,
and add new function name kvm_write_guest_virt that allow writing into a
guest virtual address.
Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
VMX initializes the TSC offset for each vcpu at different times, and
also reinitializes it for vcpus other than 0 on APIC SIPI message.
This bug causes the TSC's to appear unsynchronized in the guest, even if
the host is good.
Older Linux kernels don't handle the situation very well, so
gettimeofday is likely to go backwards in time:
http://www.mail-archive.com/kvm@vger.kernel.org/msg02955.htmlhttp://sourceforge.net/tracker/index.php?func=detail&aid=2025534&group_id=180599&atid=893831
Fix it by initializating the offset of each vcpu relative to vm creation
time, and moving it from vmx_vcpu_reset to vmx_vcpu_setup, out of the
APIC MP init path.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Using a for_each loop style removes the need to write callback and nasty
casts.
Implement the walk_shadow() using the for_each_shadow_entry().
Signed-off-by: Avi Kivity <avi@redhat.com>
Limit KVM_CAP_SET_GUEST_DEBUG only to those archs (currently x86) that
support it. This simplifies user space stub implementations.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The AMD SVM instruction family all overload the 0f 01 /3 opcode, further
multiplexing on the three r/m bits. But the code decided that anything that
isn't a vmmcall must be an lidt (which shares the 0f 01 /3 opcode, for the
case that mod = 3).
Fix by aborting emulation if this isn't a vmmcall.
Signed-off-by: Avi Kivity <avi@redhat.com>
If cr4.pge is cleared, we ought to treat any ptes in the page as non-global.
This allows us to remove the check from set_spte().
Signed-off-by: Avi Kivity <avi@redhat.com>
Don't allow a vcpu with cr4.pge cleared to use a shadow page created with
cr4.pge set; this might cause a cr3 switch not to sync ptes that have the
global bit set (the global bit has no effect if !cr4.pge).
This can only occur on smp with different cr4.pge settings for different
vcpus (since a cr4 change will resync the shadow ptes), but there's no
cost to being correct here.
Signed-off-by: Avi Kivity <avi@redhat.com>
Instead of "calculating" it on every shadow page allocation, set it once
when switching modes, and copy it when allocating pages.
This doesn't buy us much, but sets up the stage for inheriting more
information related to the mmu setup.
Signed-off-by: Avi Kivity <avi@redhat.com>
Remove some unnecessary blank lines to accord with Kernel's coding style.
Also remove vcpu_get_itir_on_fault due to no reference to it.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Remove the remaining arch fragments of the old guest debug interface
that now break non-x86 builds.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Implement KVM_IA64_VCPU_[GS]ET_STACK ioctl calls. This is required
for live migrations.
Patch is based on previous implementation that was part of old
GET/SET_REGS ioctl calls.
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Add the remaining bits to make use of debug registers also for guest
debugging, thus enabling the use of hardware breakpoints and
watchpoints.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
So far KVM only had basic x86 debug register support, once introduced to
realize guest debugging that way. The guest itself was not able to use
those registers.
This patch now adds (almost) full support for guest self-debugging via
hardware registers. It refactors the code, moving generic parts out of
SVM (VMX was already cleaned up by the KVM_SET_GUEST_DEBUG patches), and
it ensures that the registers are properly switched between host and
guest.
This patch also prepares debug register usage by the host. The latter
will (once wired-up by the following patch) allow for hardware
breakpoints/watchpoints in guest code. If this is enabled, the guest
will only see faked debug registers without functionality, but with
content reflecting the guest's modifications.
Tested on Intel only, but SVM /should/ work as well, but who knows...
Known limitations: Trapping on tss switch won't work - most probably on
Intel.
Credits also go to Joerg Roedel - I used his once posted debugging
series as platform for this patch.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
When single-stepping over STI and MOV SS, we must clear the
corresponding interruptibility bits in the guest state. Otherwise
vmentry fails as it then expects bit 14 (BS) in pending debug exceptions
being set, but that's not correct for the guest debugging case.
Note that clearing those bits is safe as we check for interruptibility
based on the original state and do not inject interrupts or NMIs if
guest interruptibility was blocked.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This rips out the support for KVM_DEBUG_GUEST and introduces a new IOCTL
instead: KVM_SET_GUEST_DEBUG. The IOCTL payload consists of a generic
part, controlling the "main switch" and the single-step feature. The
arch specific part adds an x86 interface for intercepting both types of
debug exceptions separately and re-injecting them when the host was not
interested. Moveover, the foundation for guest debugging via debug
registers is layed.
To signal breakpoint events properly back to userland, an arch-specific
data block is now returned along KVM_EXIT_DEBUG. For x86, the arch block
contains the PC, the debug exception, and relevant debug registers to
tell debug events properly apart.
The availability of this new interface is signaled by
KVM_CAP_SET_GUEST_DEBUG. Empty stubs for not yet supported archs are
provided.
Note that both SVM and VTX are supported, but only the latter was tested
yet. Based on the experience with all those VTX corner case, I would be
fairly surprised if SVM will work out of the box.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
VMX differentiates between processor and software generated exceptions
when injecting them into the guest. Extend vmx_queue_exception
accordingly (and refactor related constants) so that we can use this
service reliably for the new guest debugging framework.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Userspace has to tell the kernel module somehow that nested SVM should be used.
The easiest way that doesn't break anything I could think of is to implement
if (cpuid & svm)
allow write to efer
else
deny write to efer
Old userspaces mask the SVM capability bit, so they don't break.
In order to find out that the SVM capability is set, I had to split the
kvm_emulate_cpuid into a finding and an emulating part.
(introduced in v6)
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Normally setting the SVME bit in EFER is not allowed, as we did
not support SVM. Not since we do, we should also allow enabling
SVM mode.
v2 comes as last patch, so we don't enable half-ready code
v4 introduces a module option to enable SVM
v6 warns that nesting is enabled
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
KVM tries to read the VM_CR MSR to find out if SVM was disabled by
the BIOS. So implement read support for this MSR to make nested
SVM running.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
This adds the #VMEXIT intercept, so we return to the level 1 guest
when something happens in the level 2 guest that should return to
the level 1 guest.
v2 implements HIF handling and cleans up exception interception
v3 adds support for V_INTR_MASKING_MASK
v4 uses the host page hsave
v5 removes IOPM merging code
v6 moves mmu code out of the atomic section
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch implements VMRUN. VMRUN enters a virtual CPU and runs that
in the same context as the normal guest CPU would run.
So basically it is implemented the same way, a normal CPU would do it.
We also prepare all intercepts that get OR'ed with the original
intercepts, as we do not allow a level 2 guest to be intercepted less
than the first level guest.
v2 implements the following improvements:
- fixes the CPL check
- does not allocate iopm when not used
- remembers the host's IF in the HIF bit in the hflags
v3:
- make use of the new permission checking
- add support for V_INTR_MASKING_MASK
v4:
- use host page backed hsave
v5:
- remove IOPM merging code
v6:
- save cr4 so PAE l1 guests work
v7:
- return 0 on vmrun so we check the MSRs too
- fix MSR check to use the correct variable
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
This implements the VMLOAD and VMSAVE instructions, that usually surround
the VMRUN instructions. Both instructions load / restore the same elements,
so we only need to implement them once.
v2 fixes CPL checking and replaces memcpy by assignments
v3 makes use of the new permission checking
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Implement the hsave MSR, that gives the VCPU a GPA to save the
old guest state in.
v2 allows userspace to save/restore hsave
v4 dummys out the hsave MSR, so we use a host page
v6 remembers the guest's hsave and exports the MSR
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch implements the GIF flag and the clgi and stgi instructions that
set this flag. Only if the flag is set (default), interrupts can be received by
the CPU.
To keep the information about that somewhere, this patch adds a new hidden
flags vector. that is used to store information that does not go into the
vmcb, but is SVM specific.
I tried to write some code to make -no-kvm-irqchip work too, but the first
level guest won't even boot with that atm, so I ditched it.
v2 moves the hflags to x86 generic code
v3 makes use of the new permission helper
v6 only enables interrupt_window if GIF=1
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
These are helpers for the nested SVM implementation.
- nsvm_printk implements a debug printk variant
- nested_svm_do calls a handler that can accesses gpa-based memory
v3 makes use of the new permission checker
v6 changes:
- streamline nsvm_debug()
- remove printk(KERN_ERR)
- SVME check before CPL check
- give GP error code
- use new EFER constant
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
MSR_EFER_SVME_MASK, MSR_VM_CR and MSR_VM_HSAVE_PA are set in KVM
specific headers. Linux does have nice header files to collect
EFER bits and MSR IDs, so IMHO we should put them there.
While at it, I also changed the naming scheme to match that
of the other defines.
(introduced in v6)
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
The current VINTR intercept setters don't look clean to me. To make
the code easier to read and enable the possibilty to trap on a VINTR
set, this uses a helper function to set the VINTR intercept.
v2 uses two distinct functions for setting and clearing the bit
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
With a sufficiently new compiler and binutils, code which wasn't
previously generating .eh_frame sections has begun to. Certain
architectures (powerpc, in this case) may generate unexpected relocation
formats in response to this, preventing modules from loading.
While the new relocation types should probably be handled, revert to the
previous behaviour with regards to generation of .eh_frame sections.
(This was reported against Fedora, which appears to be the only distro
doing any building against gcc-4.4 at present: RH bz#486545.)
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Alexandre Oliva <aoliva@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert the change to the orphan dates of Windows 95, DOS, compression.
Add a new orphan date for OS/2.
Signed-off-by: Jody McIntyre <scjody@sun.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (32 commits)
ucc_geth: Fix oops when using fixed-link support
dm9000: locking bugfix
net: update dnet.c for bus_id removal
dnet: DNET should depend on HAS_IOMEM
dca: add missing copyright/license headers
nl80211: Check that function pointer != NULL before using it
sungem: missing net_device_ops
be2net: fix to restore vlan ids into BE2 during a IF DOWN->UP cycle
be2net: replenish when posting to rx-queue is starved in out of mem conditions
bas_gigaset: correctly allocate USB interrupt transfer buffer
smsc911x: reset last known duplex and carrier on open
sh_eth: Fix mistake of the address of SH7763
sh_eth: Change handling of IRQ
netns: oops in ip[6]_frag_reasm incrementing stats
net: kfree(napi->skb) => kfree_skb
net: fix sctp breakage
ipv6: fix display of local and remote sit endpoints
net: Document /proc/sys/net/core/netdev_budget
tulip: fix crash on iface up with shirq debug
virtio_net: Make virtio_net support carrier detection
...
This patch fixes bug #12208:
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12208
Subject : uml is very slow on 2.6.28 host
This turned out to be not a scheduler regression, but an already
existing problem in ptrace being triggered by subtle scheduler
changes.
The problem is this:
- task A is ptracing task B
- task B stops on a trace event
- task A is woken up and preempts task B
- task A calls ptrace on task B, which does ptrace_check_attach()
- this calls wait_task_inactive(), which sees that task B is still on the runq
- task A goes to sleep for a jiffy
- ...
Since UML does lots of the above sequences, those jiffies quickly add
up to make it slow as hell.
This patch solves this by not rescheduling in read_unlock() after
ptrace_stop() has woken up the tracer.
Thanks to Oleg Nesterov and Ingo Molnar for the feedback.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Grant picked up the wrong version of "Respect _PAGE_COHERENT on classic
ppc32 SW" (commit a4bd6a93c3)
It was missing the code to actually deal with the fixup of
_PAGE_COHERENT based on the CPU feature.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
commit b1c4a9dddf ("ucc_geth: Change
uec phy id to the same format as gianfar's") introduced a regression
in the ucc_geth driver that causes this oops when fixed-link is used:
Unable to handle kernel paging request for data at address 0x00000000
Faulting instruction address: 0xc0151270
Oops: Kernel access of bad area, sig: 11 [#1]
TMCUTU
NIP: c0151270 LR: c0151270 CTR: c0017760
REGS: cf81fa60 TRAP: 0300 Not tainted (2.6.29-rc8)
MSR: 00009032 <EE,ME,IR,DR> CR: 24024042 XER: 20000000
DAR: 00000000, DSISR: 20000000
TASK = cf81cba0[1] 'swapper' THREAD: cf81e000
GPR00: c0151270 cf81fb10 cf81cba0 00000000 c0272e20 c025f354 00001e80
cf86b08c
GPR08: d1068200 cffffb74 06000000 d106c200 42024042 10085148 0fffd000
0ffc81a0
GPR16: 00000001 00000001 00000000 007ffeb0 00000000 0000c000 cf83f36c
cf83f000
GPR24: 00000030 cf83f360 cf81fb20 00000000 d106c200 20000000 00001e80
cf83f360
NIP [c0151270] ucc_geth_open+0x330/0x1efc
LR [c0151270] ucc_geth_open+0x330/0x1efc
Call Trace:
[cf81fb10] [c0151270] ucc_geth_open+0x330/0x1efc (unreliable)
[cf81fba0] [c0187638] dev_open+0xbc/0x12c
[cf81fbc0] [c0187e38] dev_change_flags+0x8c/0x1b0
This patch fixes the issue by removing offending (and somewhat
duplicate) code from init_phy() routine, and changes _probe()
function to use uec_mdio_bus_name().
Also, since we fully construct phy_bus_id in the _probe() routine,
we no longer need ->phy_address and ->mdio_bus fields in
ucc_geth_info structure.
I wish the patch would be a bit shorter, but it seems like the only
way to fix the issue in a sane way. Luckily, the patch has been
tested with real PHYs and fixed-link, so no further regressions
expected.
Reported-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Tested-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes a locking bug in the dm9000 driver. It calls
request_irq() without setting IRQF_DISABLED ... which is
correct for handlers that support IRQ sharing, since that
behavior is not guaranteed for shared IRQs. However, its
IRQ handler then wrongly assumes that IRQs are blocked.
So the fix just uses the right spinlock primitives in the
IRQ handler.
NOTE: this is a classic example of the type of bug which
lockdep currently masks by forcibly setting IRQF_DISABLED
on IRQ handlers that did not request that flag.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hollis Blanchard