Andrew Cooper [Mon, 18 Dec 2017 13:54:25 +0000 (13:54 +0000)]
x86: Support indirect thunks from assembly code
Introduce INDIRECT_CALL and INDIRECT_JMP which either degrade to a normal
indirect branch, or dispatch to the __x86_indirect_thunk_* symbols.
Update all the manual indirect branches in to use the new thunks. The
indirect branches in the early boot and kexec path are left intact as we can't
use the compiled-in thunks at those points.
This is part of XSA-254.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Mon, 18 Dec 2017 13:54:25 +0000 (13:54 +0000)]
x86: Support compiling with indirect branch thunks
Use -mindirect-branch=thunk-extern/-mindirect-branch-register when available.
To begin with, use the retpoline thunk. Later work will add alternative
thunks which can be selected at boot time.
This is part of XSA-254.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Jan Beulich [Tue, 16 Jan 2018 16:50:59 +0000 (17:50 +0100)]
x86: allow Meltdown band-aid to be disabled
First of all we don't need it on AMD systems. Additionally allow its use
to be controlled by command line option. For best backportability, this
intentionally doesn't use alternative instruction patching to achieve
the intended effect - while we likely want it, this will be later
follow-up.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Jan Beulich [Tue, 16 Jan 2018 16:49:03 +0000 (17:49 +0100)]
x86: Meltdown band-aid against malicious 64-bit PV guests
This is a very simplistic change limiting the amount of memory a running
64-bit PV guest has mapped (and hence available for attacking): Only the
mappings of stack, IDT, and TSS are being cloned from the direct map
into per-CPU page tables. Guest controlled parts of the page tables are
being copied into those per-CPU page tables upon entry into the guest.
Cross-vCPU synchronization of top level page table entry changes is
being effected by forcing other active vCPU-s of the guest into the
hypervisor.
The change to context_switch() isn't strictly necessary, but there's no
reason to keep switching page tables once a PV guest is being scheduled
out.
This isn't providing full isolation yet, but it should be covering all
pieces of information exposure of which would otherwise require an XSA.
There is certainly much room for improvement, especially of performance,
here - first and foremost suppressing all the negative effects on AMD
systems. But in the interest of backportability (including to really old
hypervisors, which may not even have alternative patching) any such is
being left out here.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Andrew Cooper [Fri, 6 Oct 2017 13:21:32 +0000 (13:21 +0000)]
x86/Rules: Use -mskip-rax-setup if the compiler supports it
This option is available from GCC 5 onwards, and was specifically introduced
as an optimisation for Linux. When using variadic functions, the caller needs
to know how many floating point arguments were passed. Xen, like Linux,
doesn't uses floating point arguments, so doesn't need to emit code to inform
variadic functions such as printk() that there are zero arguments.
Andrew Cooper [Fri, 29 Dec 2017 12:56:24 +0000 (12:56 +0000)]
x86/bitops: Introduce variable/constant pairs for __{set,clear,change}_bit()
Just as with test_bit, the non-atomic set/clear/change helpers can be better
optimised by the compiler in the case that the nr parameter is constant, and
it often is.
This results in a general replacement of `mov $imm, %reg; bt* %reg, mem` with
the shorter and more simple `op $imm, mem`, also reducing register pressure.
The net diffstat is:
add/remove: 0/1 grow/shrink: 5/17 up/down: 90/-301 (-211)
As a piece of minor cleanup, drop unnecessary brackets in the test_bit()
macro, and fix the indentation.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Dario Faggioli <dfaggioli@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Fri, 29 Dec 2017 12:56:34 +0000 (12:56 +0000)]
xen/credit2: Drop unnecessary bit test
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: George Dunlap <george.dunlap@citrix.com> Reviewed-by: Dario Faggioli <dfaggioli@suse.com>
c/s b6c2c7f48a unfortunately broke booting on affected systems. Most of the
time, ioemul_handle_quirk() doesn't write a custom stub, and the redundant
call was depending on the seemingly-pointless writing of the default stub.
Alter the ioemul_handle_quirk() API to return a boolean if a custom stub was
written, allowing its caller to know whether it should write a default stub
instead.
Finally, adjust the /* Regular stubs */ comment to make it clearer that the 16
refers to the length of the emul stub opcode.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Tue, 9 Jan 2018 16:28:28 +0000 (16:28 +0000)]
x86/ioemul: Account for ioemul_handle_quirk() in stub length check
The opcode potentially written into ctxt->io_emul_stub[] in the case
that ioemul_handle_quirk() is overriding the default logic isnt
accounted for in the build-time check that the stubs are large enough.
Introduce IOEMUL_QUIRK_STUB_BYTES and use for both the main and quirk
stub cases. As a slim optimisation, avoid writing out the default stub
when we know we are going to overwrite it.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
x86: Don't use potentially incorrect CPUID values for topology information
Intel says for CPUID leaf 0Bh:
"Software must not use EBX[15:0] to enumerate processor
topology of the system. This value in this field
(EBX[15:0]) is only intended for display/diagnostic
purposes. The actual number of logical processors
available to BIOS/OS/Applications may be different from
the value of EBX[15:0], depending on software and platform
hardware configurations."
And yet, we're using them to derive the number cores in a package
and the number of siblings in a core.
Derive the number of siblings and cores from EAX instead, which is
intended for that.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Andrew Cooper [Wed, 16 Aug 2017 17:06:59 +0000 (18:06 +0100)]
x86/entry: Remove support for partial cpu_user_regs frames
Save all GPRs on entry to Xen.
The entry_int82() path is via a DPL1 gate, only usable by 32bit PV guests, so
can get away with only saving the 32bit registers. All other entrypoints can
be reached from 32 or 64bit contexts.
This is part of XSA-254.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Roger Pau Monné [Thu, 4 Jan 2018 13:29:16 +0000 (14:29 +0100)]
x86/upcall: inject a spurious event after setting upcall vector
In case the vCPU has pending events to inject. This fixes a bug that
happened if the guest mapped the vcpu info area using
VCPUOP_register_vcpu_info without having setup the event channel
upcall, and then setup the upcall vector.
In this scenario the guest would not receive any upcalls, because the
call to VCPUOP_register_vcpu_info would have marked the vCPU as having
pending events, but the vector could not be injected because it was
not yet setup.
This has not caused issues so far because all the consumers first
setup the vector callback and then map the vcpu info page, but there's
no limitation that prevents doing it in the inverse order.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
This patch adds the old value param and the onchangeonly option
to the VM_EVENT_REASON_MOV_TO_MSR event.
The param was added to the vm_event_mov_to_msr struct and to the
hvm_monitor_msr function. Finally I've changed the bool_t param
to a bool for the hvm_msr_write_intercept function.
Signed-off-by: Alexandru Isaila <aisaila@bitdefender.com> Acked-by: Tamas K Lengyel <tamas@tklengyel.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Thu, 4 Jan 2018 13:27:38 +0000 (14:27 +0100)]
x86/msr: Free msr_vcpu_policy during vcpu destruction
c/s 4187f79dc7 "x86/msr: introduce struct msr_vcpu_policy" introduced a
per-vcpu memory allocation, but failed to free it in the clean vcpu
destruction case.
This is XSA-253.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Fri, 2 Dec 2016 15:00:41 +0000 (15:00 +0000)]
xen/x86: Correct mandatory and SMP barrier definitions
Barriers are a complicated topic, a source of confusion, and their incorrect
use is a common cause of bugs. It really doesn't help when Xen's API is the
same as Linux, but its ABI different.
Bring the two back in line, so programmers stand a chance of actually getting
their usage correct.
Drop the links in the comment, both of which are now stale. Instead, refer to
the vendor system manuals in a generic way.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Fri, 2 Dec 2016 15:00:41 +0000 (15:00 +0000)]
xen/x86: Drop unnecessary barriers
x86's current implementation of wmb() is a compiler barrier. As a result, the
only change in this patch is to remove an mfence instruction from
cpuidle_disable_deep_cstate().
None of these barriers serve any purpose. They are not synchronising with
remote cpus, and their compiler-barrier properties are not needed for
correctness purposes.
Furthermore, these wmb()'s specifically do not want to turn into sfence
instructions in future changes where wmb()'s implementation is corrected.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Various minor optimizations in rb_erase():
- Avoid multiple loading of node->__rb_parent_color when computing parent
and color information (possibly not in close sequence, as there might
be further branches in the algorithm)
- In the 1-child subcase of case 1, copy the __rb_parent_color field from
the erased node to the child instead of recomputing it from the desired
parent and color
- When searching for the erased node's successor, differentiate between
cases 2 and 3 based on whether any left links were followed. This avoids
a condition later down.
- In case 3, keep a pointer to the erased node's right child so we don't
have to refetch it later to adjust its parent.
- In the no-childs subcase of cases 2 and 3, place the rebalance assigment
last so that the compiler can remove the following if(rebalance) test.
Also, added some comments to illustrate cases 2 and 3.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 4f035ad67f4633c233cb3642711d49b4efc9c82d]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
rbtree: handle 1-child recoloring in rb_erase() instead of rb_erase_color()
An interesting observation for rb_erase() is that when a node has
exactly one child, the node must be black and the child must be red.
An interesting consequence is that removing such a node can be done by
simply replacing it with its child and making the child black,
which we can do efficiently in rb_erase(). __rb_erase_color() then
only needs to handle the no-childs case and can be modified accordingly.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 46b6135a7402ac23c5b25f2bd79b03bab8f98278]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
When looking to fetch a node's sibling, we went through a sequence of:
- check if node is the parent's left child
- if it is, then fetch the parent's right child
This can be replaced with:
- fetch the parent's right child as an assumed sibling
- check that node is NOT the fetched child
This avoids fetching the parent's left child when node is actually
that child. Saves a bit on code size, though it doesn't seem to make
a large difference in speed.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 59633abf34e2f44b8e772a2c12a92132aa7c2220]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Jan Beulich [Wed, 3 Jan 2018 10:05:05 +0000 (11:05 +0100)]
simplify xenmem_add_to_physmap_batch()
There's no need for
- advancing the handles and at the same time using
__copy_{from,to}_guest_offset(),
- an "out" label,
- local variables "done" and (function scope) "rc".
To better reflect its resulting use also rename the function's "start"
parameter to "extent".
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Jan Beulich [Wed, 3 Jan 2018 10:04:26 +0000 (11:04 +0100)]
x86/E820: improve insn selection
..., largely to shrink code size a little:
- use TEST instead of CMP with zero immediate
- use MOVZWL instead of AND with 0xffff immediate
- compute final highmem_bk value in registers, accessing memory just
once
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Jan Beulich [Wed, 3 Jan 2018 10:03:56 +0000 (11:03 +0100)]
x86/E820: don't overrun array
The bounds check needs to be done after the increment, not before, or
else it needs to use a one lower immediate. Also use word operations
rather than byte ones for both the increment and the compare (allowing
E820_BIOS_MAX to be more easily bumped, should the need ever arise).
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Jan Beulich [Wed, 3 Jan 2018 10:02:10 +0000 (11:02 +0100)]
x86/Intel: drop another 32-bit leftover
None of the models MISC_ENABLE MSR access is excluded for support 64-bit
mode - drop the conditional from early_init_intel(). Also convert
pointless rdmsr_safe() elsewhere to rdmsrl().
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Andrew Cooper [Wed, 5 Oct 2016 11:42:15 +0000 (12:42 +0100)]
xen/x86: Replace appropriate mandatory barriers with SMP barriers
There is no functional change. Xen currently assignes smp_* meaning to
the non-smp_* barriers.
All of these uses are just to deal with shared memory between multiple
processors, which means that the smp_*() varients are the correct ones to use.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
rbtree: low level optimizations in __rb_erase_color()
In __rb_erase_color(), we often already have pointers to the nodes being
rotated and/or know what their colors must be, so we can generate more
efficient code than the generic __rb_rotate_left() and __rb_rotate_right()
functions.
Also when the current node is red or when flipping the sibling's color,
the parent is already known so we can use the more efficient
rb_set_parent_color() function to set the desired color.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 6280d2356fd8ad0936a63c10dc1e6accf48d0c61]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
rbtree: optimize case selection logic in __rb_erase_color()
In __rb_erase_color(), we have to select one of 3 cases depending on the
color on the 'other' node children. If both children are black, we flip a
few node colors and iterate. Otherwise, we do either one or two tree
rotations, depending on the color of the 'other' child opposite to 'node',
and then we are done.
The corresponding logic had duplicate checks for the color of the 'other'
child opposite to 'node'. It was checking it first to determine if both
children are black, and then to determine how many tree rotations are
required. Rearrange the logic to avoid that extra check.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit e125d1471a4f8f1bf7ea9a83deb8d23cb40bd712]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
rbtree: adjust node color in __rb_erase_color() only when necessary
In __rb_erase_color(), we were always setting a node to black after
exiting the main loop. And in one case, after fixing up the tree to
satisfy all rbtree invariants, we were setting the current node to root
just to guarantee a loop exit, at which point the root would be set to
black. However this is not necessary, as the root of an rbtree is already
known to be black. The only case where the color flip is required is when
we exit the loop due to the current node being red, and it's easiest to
just do the flip at that point instead of doing it after the loop.
[adrian.hunter@intel.com: perf tools: fix build for another rbtree.c change] Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit d6ff1273928ebf15466a85b7e1810cd00e72998b]
Ported only rbtree.c to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
rbtree: low level optimizations in rb_insert_color()
- Use the newly introduced rb_set_parent_color() function to flip the color
of nodes whose parent is already known.
- Optimize rb_parent() when the node is known to be red - there is no need
to mask out the color in that case.
- Flipping gparent's color to red requires us to fetch its rb_parent_color
field, so we can reuse it as the parent value for the next loop iteration.
- Do not use __rb_rotate_left() and __rb_rotate_right() to handle tree
rotations: we already have pointers to all relevant nodes, and know their
colors (either because we want to adjust it, or because we've tested it,
or we can deduce it as black due to the node proximity to a known red node).
So we can generate more efficient code by making use of the node pointers
we already have, and setting both the parent and color attributes for
nodes all at once. Also in Case 2, some node attributes don't have to
be set because we know another tree rotation (Case 3) will always follow
and override them.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 5bc9188aa207dafd47eab57df7c4fe5b3d3f636a]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
rbtree: adjust root color in rb_insert_color() only when necessary
The root node of an rbtree must always be black. However,
rb_insert_color() only needs to maintain this invariant when it has been
broken - that is, when it exits the loop due to the current (red) node
being the root. In all other cases (exiting after tree rotations, or
exiting due to an existing black parent) the invariant is already
satisfied, so there is no need to adjust the root node color.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 6d58452dc066db61acdff7b84671db1b11a3de1c]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
rbtree: break out of rb_insert_color loop after tree rotation
It is a well known property of rbtrees that insertion never requires more
than two tree rotations. In our implementation, after one loop iteration
identified one or two necessary tree rotations, we would iterate and look
for more. However at that point the node's parent would always be black,
which would cause us to exit the loop.
We can make the code flow more obvious by just adding a break statement
after the tree rotations, where we know we are done. Additionally, in the
cases where two tree rotations are necessary, we don't have to update the
'node' pointer as it wouldn't be used until the next loop iteration, which
we now avoid due to this break statement.
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 1f0528653e41ec230c60f5738820e8a544731399]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
rbtree: move some implementation details from rbtree.h to rbtree.c
rbtree users must use the documented APIs to manipulate the tree
structure. Low-level helpers to manipulate node colors and parenthood are
not part of that API, so move them to lib/rbtree.c
Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit bf7ad8eeab995710c766df49c9c69a8592ca0216]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Empty nodes have no color. We can make use of this property to simplify
the code emitted by the RB_EMPTY_NODE and RB_CLEAR_NODE macros. Also,
we can get rid of the rb_init_node function which had been introduced by
commit 88d19cf37952 ("timers: Add rb_init_node() to allow for stack
allocated rb nodes") to avoid some issue with the empty node's color not
being initialized.
I'm not sure what the RB_EMPTY_NODE checks in rb_prev() / rb_next() are
doing there, though. axboe introduced them in commit 10fd48f2376d
("rbtree: fixed reversed RB_EMPTY_NODE and rb_next/prev"). The way I
see it, the 'empty node' abstraction is only used by rbtree users to
flag nodes that they haven't inserted in any rbtree, so asking the
predecessor or successor of such nodes doesn't make any sense.
One final rb_init_node() caller was recently added in sysctl code to
implement faster sysctl name lookups. This code doesn't make use of
RB_EMPTY_NODE at all, and from what I could see it only called
rb_init_node() under the mistaken assumption that such initialization was
required before node insertion.
[sfr@canb.auug.org.au: fix net/ceph/osd_client.c build] Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 4c199a93a2d36b277a9fd209a0f2793f8460a215]
Ported rbtree.h and rbtree.c changes which are relevant to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Wolfram Strepp [Wed, 20 Dec 2017 17:00:49 +0000 (18:00 +0100)]
rbtree: remove redundant if()-condition in rb_erase()
Furthermore, notice that the initial checks:
if (!node->rb_left)
child = node->rb_right;
else if (!node->rb_right)
child = node->rb_left;
else
{
...
}
guarantee that old->rb_right is set in the final else branch, therefore
we can omit checking that again.
Signed-off-by: Wolfram Strepp <wstrepp@gmx.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Linux commit 4b324126e0c6c3a5080ca3ec0981e8766ed6f1ee]
Ported to Xen.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Wed, 20 Dec 2017 11:52:15 +0000 (11:52 +0000)]
x86/nops: Switch to the P6 nops as a compile-time default
Along with c/s d7128e735031 switching the runtime choice of best nops, switch
the compile-time default to P6 nops. This is more efficient on most
processors for alternative points which add/remove code, rather than switch
between two different pieces of code.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Jan Beulich [Wed, 20 Dec 2017 09:12:11 +0000 (10:12 +0100)]
x86/shadow: make 1-bit-disable match 1-bit-enable
shadow_one_bit_enable() sets PG_SH_enable (if not already set of course)
in addition to the bit being requested. Make shadow_one_bit_disable()
behave similarly - clear PG_SH_enable if that's the only bit remaining.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Tim Deegan <tim@xen.org>
Jan Beulich [Wed, 20 Dec 2017 09:05:16 +0000 (10:05 +0100)]
x86/shadow: ignore sh_pin() failure in one more case
Following what we've already done in the XSA-250 fix, convert another
sh_pin() caller to no longer fail the higher level operation if pinning
fails, as pinning is a performance optimization only in those places.
Suggested-by: Tim Deegan <tim@xen.org> Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Tim Deegan <tim@xen.org>
Jan Beulich [Wed, 20 Dec 2017 09:04:16 +0000 (10:04 +0100)]
x86/shadow: drop further 32-bit relics
PV guests don't ever get shadowed in other than 4-level mode anymore;
commit 5a3ce8f85e ("x86/shadow: drop stray name tags from
sh_{guest_get,map}_eff_l1e()") didn't go quite fare enough (and there's
a good chance that further cleanup opportunity exists, which I simply
didn't notice).
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Tim Deegan <tim@xen.org>
Jan Beulich [Wed, 20 Dec 2017 09:03:20 +0000 (10:03 +0100)]
x86: introduce NOP9 forms
Both Intel and AMD recommend an operand-size-override-prefixed long NOP
form for covering 9 bytes, so introduce this and use it in p6_nops[] to
allow further reducing the number of NOPs needed when covering larger
ranges.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Roger Pau Monné [Wed, 20 Dec 2017 09:00:16 +0000 (10:00 +0100)]
x86/dom0: remove is_pv_domain leftovers from the PV domain builder
Those where added when PVHv1 was sharing the domain builder with PV.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Roger Pau Monné [Wed, 20 Dec 2017 08:59:21 +0000 (09:59 +0100)]
x86/dom0: remove autotranslate leftovers
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Roger Pau Monne [Tue, 19 Dec 2017 14:17:52 +0000 (14:17 +0000)]
libxl/pvh: force PVH guests to use the xenstore shutdown
PVH guests are all required to support the xenstore-based shutdown
signalling, since there is no other way for a PVH guest to be
requested to shut down.
For HVM guests we check whether the guest has installed a PV-on-HVM
interrupt callback; that does not make sense for PVH guests.
So for PVH guests, take the PV path: assume that all PVH guests have
suitable xenstore drivers.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Acked-by: Ian Jackson <ian.jackson@eu.citrix.com> Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Jan Beulich [Fri, 15 Dec 2017 10:17:19 +0000 (11:17 +0100)]
domctl: improve locking during domain destruction
There is no need to hold the global domctl lock across domain_kill() -
the domain lock is fully sufficient here, and parallel cleanup after
multiple domains performs quite a bit better this way.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Jan Beulich [Fri, 15 Dec 2017 10:14:31 +0000 (11:14 +0100)]
x86: remove _PAGE_PSE check from get_page_from_l2e()
With L2_DISALLOW_MASK containing _PAGE_PSE unconditionally as of commit 56fff3e5e9 ("x86: nuke PV superpage option and code") there's no point
anymore in separately checking for the bit.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Jan Beulich [Fri, 15 Dec 2017 10:11:36 +0000 (11:11 +0100)]
x86/HVM: fix hvmemul_rep_outs_set_context()
There were two issues with this function: Its use of
hvmemul_do_pio_buffer() was wrong (the function deals only with
individual port accesses, not repeated ones, i.e. passing it
"*reps * bytes_per_rep" does not have the intended effect). And it
could have processed a larger set of operations in one go than was
probably intended (limited just by the size that xmalloc() can hand
back).
By converting to proper use of hvmemul_do_pio_buffer(), no intermediate
buffer is needed at all. As a result a preemption check is being added.
Also drop unused parameters from the function.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Razvan Cojocaru <rcojocaru@bitdefender.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Yi Sun [Fri, 20 Oct 2017 08:50:00 +0000 (10:50 +0200)]
x86: implement data structure and CPU init flow for MBA
This patch implements main data structures of MBA.
Like CAT features, MBA HW info has cos_max which means the max thrtl
register number, and thrtl_max which means the max throttle value
(delay value). It also has a flag to represent if the throttle
value is linear or non-linear.
One thrtl register of MBA stores a throttle value for one or more
domains. The throttle value means the delay applied to traffic between
L2 cache and next cache level.
This patch also implements init flow for MBA and register stub
callback functions.
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Yi Sun [Fri, 20 Oct 2017 08:50:00 +0000 (10:50 +0200)]
x86: a few optimizations to psr codes
This patch refines psr codes:
1. Change type of 'cat_init_feature' to 'bool' to remove the pointless
returning of error code.
2. Move printk in 'cat_init_feature' to reduce a return path.
3. Define a local variable 'feat_mask' in 'psr_cpu_init' to reduce calling of
'cpuid_count_leaf()'.
4. Change 'PSR_INFO_IDX_CAT_FLAG' to 'PSR_INFO_IDX_CAT_FLAGS'.
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Yi Sun [Fri, 20 Oct 2017 08:50:00 +0000 (10:50 +0200)]
x86: rename 'cbm_type' to 'psr_type' to make it general
This patch renames 'cbm_type' to 'psr_type' to generalize it.
Then, we can reuse this for all psr allocation features.
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Yi Sun [Tue, 24 Oct 2017 09:33:00 +0000 (11:33 +0200)]
Rename PSR sysctl/domctl interfaces and xsm policy to make them be general
This patch renames PSR sysctl/domctl interfaces and related xsm policy to
make them be general for all resource allocation features but not only
for CAT. Then, we can resuse the interfaces for all allocation features.
Basically, it changes 'psr_cat_op' to 'psr_alloc', and remove 'CAT_' from some
macros. E.g.:
1. psr_cat_op -> psr_alloc
2. XEN_DOMCTL_psr_cat_op -> XEN_DOMCTL_psr_alloc
3. XEN_SYSCTL_psr_cat_op -> XEN_SYSCTL_psr_alloc
4. XEN_DOMCTL_PSR_CAT_SET_L3_CBM -> XEN_DOMCTL_PSR_SET_L3_CBM
5. XEN_SYSCTL_PSR_CAT_get_l3_info -> XEN_SYSCTL_PSR_get_l3_info
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com> Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
This patch creates MBA feature document in doc/features/. It describes
key points to implement MBA which is described in details in Intel SDM
"Introduction to Memory Bandwidth Allocation".
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Andrew Cooper [Wed, 6 Dec 2017 17:46:20 +0000 (17:46 +0000)]
x86/vmx: Don't use hvm_inject_hw_exception() in long_mode_do_msr_write()
Since c/s 49de10f3c1718 "x86/hvm: Don't raise #GP behind the emulators back
for MSR accesses", returning X86EMUL_EXCEPTION has pushed the exception
generation to the top of the call tree.
Using hvm_inject_hw_exception() and returning X86EMUL_EXCEPTION causes a
double #GP injection, which combines to #DF.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
Andrew Cooper [Wed, 13 Dec 2017 16:55:38 +0000 (16:55 +0000)]
xen/efi: Fix build with clang-5.0
The clang-5.0 build is reliably failing with:
Error: size of boot.o:.text is 0x01
which is because efi_arch_flush_dcache_area() exists as a single ret
instruction. Mark it as __init like everything else in the files.
Spotted by Travis.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Acked-by: Jan Beulich <jbeulich@suse.com>
Tom Lendacky [Thu, 30 Nov 2017 22:46:40 +0000 (16:46 -0600)]
x86/microcode: Add support for fam17h microcode loading
The size for the Microcode Patch Block (MPB) for an AMD family 17h
processor is 3200 bytes. Add a #define for fam17h so that it does
not default to 2048 bytes and fail a microcode load/update.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
[Linux commit f4e9b7af0cd58dd039a0fb2cd67d57cea4889abf]
Ported to Xen.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
Julien Grall [Tue, 12 Dec 2017 19:02:12 +0000 (19:02 +0000)]
xen/arm: traps: Merge do_trap_instr_abort_guest and do_trap_data_abort_guest
The two helpers do_trap_instr_abort_guest and do_trap_data_abort_guest
are used trap stage-2 abort. While the former is only handling prefetch
abort and the latter data abort, they are very similarly and does not
warrant to have separate helpers.
For instance, merging the both will make easier to maintain stage-2 abort
handling. So consolidate the two helpers in a new helper
do_trap_stage2_abort.
Julien Grall [Tue, 12 Dec 2017 19:02:11 +0000 (19:02 +0000)]
xen/arm: traps: Move the definition of mmio_info_t in try_handle_mmio
mmio_info_t is currently filled by do_trap_data_guest_abort but only
important when emulation an MMIO region.
A follow-up patch will merge stage-2 prefetch abort and stage-2 data abort
in a single helper. To prepare that, mmio_info_t is now filled by
try_handle_mmio.
Julien Grall [Tue, 12 Dec 2017 19:02:10 +0000 (19:02 +0000)]
xen/arm: traps: Remove the field gva from mmio_info_t
mmio_info_t is used to gather information in order do emulation of a
region. Guest virtual address is unlikely to be a useful information and
not currently used. So remove the field gva from mmio_info_t and replace
by a local variable.
Julien Grall [Tue, 12 Dec 2017 19:02:07 +0000 (19:02 +0000)]
xen/arm: p2m: Rename p2m_flush_tlb and p2m_flush_tlb_sync
Rename p2m_flush_tlb and p2m_flush_tlb_sync to respectively
p2m_tlb_flush and p2m_force_tlb_flush_sync.
At first glance, inverting 'flush' and 'tlb' might seem pointless but
would be helpful in the future in order to get more easily some code ported
from x86 P2M or even to shared with.
For p2m_flush_tlb_sync, the 'force' was added because the TLBs are
flush unconditionally. A follow-up patch will add an helper to flush
TLBs only in certain cases.
Julien Grall [Tue, 12 Dec 2017 19:02:06 +0000 (19:02 +0000)]
xen/arm: domain_build: Use copy_to_guest_phys_flush_dcache in dtb_load
The function dtb_load is dealing with IPA but uses gvirt_to_maddr to do
the translation. This is currently working fine because the stage-1 MMU
is disabled.
Rather than relying on such assumption, use the new
copy_to_guest_phys_flush_dcache. This also result to a slightly more
comprehensible code.
Julien Grall [Tue, 12 Dec 2017 19:02:05 +0000 (19:02 +0000)]
xen/arm: domain_build: Rework initrd_load to use the generic copy helper
The function initrd_load is dealing with IPA but uses gvirt_to_maddr to
do the translation. This is currently working fine because the stage-1 MMU
is disabled.
Furthermore, the function is implementing its own copy to guest resulting
in code duplication and making more difficult to update the logic in
page-tables (such support for Populate On Demand).
The new copy_to_guest_phys_flush_dcache could be used here by temporarily
mapping the full initrd in the virtual space.
Julien Grall [Tue, 12 Dec 2017 19:02:04 +0000 (19:02 +0000)]
xen/arm: kernel: Rework kernel_zimage_load to use the generic copy helper
The function kernel_zimage is dealing with IPA but uses gvirt_to_maddr to
do the translation. This is currently working fine because the stage-1 MMU
is disabled.
Furthermore, the function is implementing its own copy to guest resulting
in code duplication and making more difficult to update the logic in
page-tables (such support for Populate On Demand).
The new copy_to_guest_phys_flush_dcache could be used here by
temporarily mapping the full kernel in the virtual space.
Julien Grall [Tue, 12 Dec 2017 19:02:02 +0000 (19:02 +0000)]
xen/arm: Extend copy_to_guest to support copying from/to guest physical address
The only differences between copy_to_guest and access_guest_memory_by_ipa are:
- The latter does not support copying data crossing page boundary
- The former is copying from/to guest VA whilst the latter from
guest PA
copy_to_guest can easily be extended to support copying from/to guest
physical address. For that a new bit is used to tell whether linear
address or ipa is been used.
Lastly access_guest_memory_by_ipa is reimplemented using copy_to_guest.
This also has the benefits to extend the use of it, it is now possible
to copy data crossing page boundary.
Julien Grall [Tue, 12 Dec 2017 19:02:01 +0000 (19:02 +0000)]
xen/arm: guest_copy: Extend the prototype to pass the vCPU
Currently, guest_copy assumes the copy will only be done for the current
vCPU. copy_guest is meant to be vCPU agnostic, so extend the prototype
to pass the vCPU.
At the same time, encapsulate the vCPU in an union to allow extension
for copying from a guest domain (ipa case) in the future.
projects / xen.git / log