Commit Graph
100 Commits
Author SHA1 Message Date
Jan Beulich bf08a8a08a x86/HVM: use single (atomic) MOV for aligned emulated writes
Using memcpy() may result in multiple individual byte accesses
(dependening how memcpy() is implemented and how the resulting insns,
e.g. REP MOVSB, get carried out in hardware), which isn't what we
want/need for carrying out guest insns as correctly as possible. Fall
back to memcpy() only for accesses not 2, 4, or 8 bytes in size.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2020-01-03 17:04:41 +01:00
Jan Beulich c663d0c815 x86/mm: drop redundant smp_wmb() from _put_final_page_type()
get_page_light()'s use of cmpxchg() is a full barrier already anyway.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 10:02:48 +01:00
Jan Beulich c497bfa633 x86/mm: avoid IOMMU operations in more cases in _get_page_type()
All that really matters is whether writability of a page changes; in
particular e.g. page table -> page table (but different levels)
transitions do not require unmapping the page from the IOMMU again.

Note that the XSA-288 fix did arrange for PGT_none pages not needing
special consideration here.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 10:01:43 +01:00
Jan Beulich 3d4985fc84 x86: move vgc_flags to struct pv_vcpu
There's been effectively no use of the field for HVM.

Also shrink the field to unsigned int, even if this doesn't immediately
yield any space benefit for the structure itself. The resulting 32-bit
padding slot can eventually be used for some other field. The change in
size makes accesses slightly more efficient though, as no REX.W prefix
is going to be needed anymore on the respective insns.

Mirror the HVM side change here (dropping of setting the field to
VGCF_online) also to Arm, on the assumption that it was cloned like
this originally. VGCF_online really should simply and consistently be
the guest view of the inverse of VPF_down, and hence needs representing
only in the get/set vCPU context interfaces.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 09:57:05 +01:00
Jan Beulich 3f8c7d3d76 x86: move and rename NR_VECTORS
This is an architectural definition, so move it to x86-defns.h and add
an X86_ prefix. This in particular allows removing the inclusion of
irq_vectors.h by virtually every source file, due to irq.h and
hvm/vmx/vmcs.h having needed to include it: Changes to IRQ vector usage
shouldn't really trigger full rebuilds.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 09:56:04 +01:00
Jan Beulich 3fba06ba9f x86/IRQ: re-use legacy vector ranges on APs
The legacy vectors have been actively used on CPU 0 only. CPUs not
sharing vector space with CPU 0 can easily re-use them, slightly
increasing the relatively scarce resource of total vectors available in
the system. As a result the legacy vector range simply becomes a
sub-range of the dynamic one, with an extra check performed in
_assign_irq_vector() (we can't rely on the
"per_cpu(vector_irq, new_cpu)[vector] >= 0" check in the subsequent
loop, as we need to also exclude vectors of disabled legacy IRQs).

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 09:54:59 +01:00
Jan Beulich 8fb4e83dc3 x86/IRQ: flip legacy and dynamic vector ranges
There's no reason to have the PIC vectors (which are typically entirely
unused on 64-bit systems anyway) right below the high priority ones. Put
them in the lowest possible range, and shift the dynamic vector range up
accordingly. This is to reduce the priority of PIC vectors in the LAPIC
vs all other ones.

Note that irq_move_cleanup_interrupt(), despite using
FIRST_DYNAMIC_VECTOR, does not get touched, as PIC interrupts aren't
movable.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 09:54:19 +01:00
Jan Beulich 53fd9dafeb x86/IRQ: simplify pending EOI stack logic for internally used IRQs
In 5655ce8b1e ("x86/IRQ: make internally used IRQs also honor the
pending EOI stack") it was mentioned that both the check_eoi_deferral
per-CPU variable and the cpu_has_pending_apic_eoi() were added just to
have as little impact on existing behavior as possible, to reduce the
risk of a last minute regression in 4.13.

Upon closer inspection, dropping the variable is an option only if all
callers of ->end() would assume the responsibility of also calling
flush_ready_eoi(). Therefore only drop the cpu_has_pending_apic_eoi()
guard now.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 09:53:35 +01:00
Jan Beulich 189da94865 x86/IRQ: move and rename __do_IRQ_guest()
This is for it to be next to do_IRQ(). Beyond the actual code movement
this
- drops the leading underscores,
- passes in desc and vector, rather than irq,
- flips the order of two ASSERT()s,
- changes i and sp to unsigned int,
- restricts the scope of d and sp,
- corrects style.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 09:52:41 +01:00
Jan Beulich 160e7544d6 x86/IRQ: move do_IRQ()
This is to avoid forward declarations of static functions. Beyond the
actual code movement this does
- u8 -> uint8_t,
- convert to Xen style,
- drop unnecessary parentheses and alike,
- strip trailing white space.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-27 09:51:52 +01:00
Jan Beulich a555d3363d x86emul: introduce CASE_SIMD_..._FP_VEX()
Since there are many AVX{,2} insns having legacy SIMD counterparts, have
macros covering both in one go. This (imo) improves readability and helps
prepare for optionally disabling SIMD support in the emulator.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-23 14:16:11 +01:00
Jan Beulich 053118f7ac x86emul: drop CASE_SIMD_DOUBLE_FP()
It's used only by CASE_SIMD_ALL_FP(), which can equally well be
implemented in terms of CASE_SIMD_{PACKED,SCALAR}_FP().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-23 14:15:17 +01:00
Jan Beulich 2520620266 x86emul: introduce CASE_SIMD_PACKED_INT_VEX()
Since there are many AVX{,2} insns having legacy MMX and SIMD
counterparts, have a macro covering all three in one go. This (imo)
improves readability (simply by the shrunk number of lines) and helps
prepare for optionally disabling MMX and SIMD support in the emulator.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-23 14:13:37 +01:00
Jan Beulich f71dbc2f4c x86emul: use CASE_SIMD_PACKED_INT() where possible
This (imo) improves readability (simply by the shrunk number of lines)
and helps prepare for optionally disabling MMX and SIMD support in the
emulator.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-20 16:46:20 +01:00
Jan Beulich 619a7119da x86: explicitly disallow guest access to PPIN
To fulfill the "protected" in its name, don't let the real hardware
values leak. While we could report a control register value expressing
this (which I would have preferred), unconditionally raise #GP for all
accesses (in the interest of getting this done).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-20 16:30:13 +01:00
Jan Beulich 5c13ed79f3 x86: provide Dom0 access to PPIN via XENPF_resource_op
It was requested that we provide a way independent of the MCE reporting
interface that Dom0 software could use to get hold of the values for
particular CPUs.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-18 14:49:59 +01:00
Jan Beulich dea5d6dd05 x86: include the PPIN in MCE records when available
Quoting the respective Linux commit:

    Intel Xeons from Ivy Bridge onwards support a processor identification
    number set in the factory. To the user this is a handy unique number to
    identify a particular CPU. Intel can decode this to the fab/production
    run to track errors. On systems that have it, include it in the machine
    check record. I'm told that this would be helpful for users that run
    large data centers with multi-socket servers to keep track of which CPUs
    are seeing errors.

Newer AMD CPUs support this too, at different MSR numbers.

Take the opportunity and hide __MC_NMSRS from the public interface going
forward.

[Linux commit 3f5a7896a5096fd50030a04d4c3f28a7441e30a5]
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-18 14:49:10 +01:00
Jan Beulich 2d696d6145 x86emul: correct far branch handling for 64-bit mode
AMD and friends explicitly specify that 64-bit operands aren't possible
for these insns. Nevertheless REX.W isn't fully ignored: It still
cancels a possible operand size override (0x66). Intel otoh explicitly
provides for 64-bit operands on the respective insn page of the SDM.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-16 17:37:09 +01:00
Jan Beulich ffa21ea530 x86emul: correct LFS et al handling for 64-bit mode
AMD and friends explicitly specify that 64-bit operands aren't possible
for these insns. Nevertheless REX.W isn't fully ignored: It still
cancels a possible operand size override (0x66). Intel otoh explicitly
provides for 64-bit operands on the respective insn page of the SDM.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-16 17:35:50 +01:00
Jan Beulich 99dd522c3f x86emul: correct segment override decode for 64-bit mode
The legacy / compatibility mode ES, CS, SS, and DS overrides are fully
ignored prefixes in 64-bit mode, i.e. they in particular don't cancel an
earlier FS or GS one. (They don't violate the REX-prefix-must-be-last
rule though.)

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-16 17:34:46 +01:00
Jan Beulich 7442006b9f x86+Arm32: make find_next_{,zero_}bit() have well defined behavior
These functions getting used with the 2nd and 3rd arguments being equal
wasn't well defined: Arm64 reliably returns the value of the 2nd
argument in this case, while on x86 for bitmaps up to 64 bits wide the
return value was undefined (due to the undefined behavior of a shift of
a value by the number of bits it's wide) when the incoming value was 64.
On Arm32 an actual out of bounds access would happen when the
size/offset value is a multiple of 32; if this access doesn't fault, the
return value would have been sufficiently correct afaict.

Make the functions consistently tolerate the last two arguments being
equal (and in fact the 3rd argument being greater or equal to the 2nd),
in favor of finding and fixing all the use sites that violate the
original more strict assumption.

This is XSA-307.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien@xen.org>
2019-12-11 14:06:18 +01:00
Jan Beulich b73aad4c8b x86/i8259A: don't open-code LEGACY_VECTOR()
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-09 14:03:01 +01:00
Jan Beulich 2d7572cdfa lz4: refine commit 9143a6c55e for the 64-bit case
I clearly went too far there: While the LZ4_WILDCOPY() instances indeed
need prior guarding, LZ4_SECURECOPY() needs this only in the 32-bit case
(where it simply aliases LZ4_WILDCOPY()). "cpy" can validly point
(slightly) below "op" in these cases, due to

		cpy = op + length - (STEPSIZE - 4);

where length can be as low as 0 and STEPSIZE is 8. However, instead of
removing the check via "#if !LZ4_ARCH64", refine it such that it would
also properly work in the 64-bit case, aborting decompression instead
of continuing on bogus input.

Reported-by: Mark Pryor <pryorm09@gmail.com>
Reported-by: Jeremi Piotrowski <jeremi.piotrowski@gmail.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Mark Pryor <pryorm09@gmail.com>
Tested-by: Jeremi Piotrowski <jeremi.piotrowski@gmail.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-09 14:01:25 +01:00
Jan Beulich b813ce366a x86/CPUID: RSTR_FP_ERR_PTRS depends on FPU
There's nothing to restore here if there's no FPU in the first place.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-09 14:00:15 +01:00
Jan Beulich 8359dde718 x86: support Atom Tremont
Add model 0x86 to relevant switch() statements, as per SDM 069 Vol 4.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-06 11:02:48 +01:00
Jan Beulich 0f216f8eb8 x86: don't offer Hyper-V option when "PV Shim Exclusive"
This only added dead code. Use "if" instead of "depends on" to make
(halfway) clear that other guest options should also go in the same
block. Move the option down such that the shim related options get
presented first, avoiding to ask the question when the answer may end
up being discarded.

While in the neighborhood also bring PV_SHIM_EXCLUSIVE into more
"canonical" shape.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-06 11:02:09 +01:00
Jan Beulich f5536cd68b x86/nEPT: ditch nept_sp_entry()
It's bogusly non-static. It making the call sites actually less easy to
read, and there being another open-coded use in the file - let's just
get rid of it.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
2019-12-06 11:01:18 +01:00
Jan Beulich d5294a302c x86: avoid HPET use on certain Intel platforms
Linux commit fc5db58539b49351e76f19817ed1102bf7c712d0 says

"Some Coffee Lake platforms have a skewed HPET timer once the SoCs entered
 PC10, which in consequence marks TSC as unstable because HPET is used as
 watchdog clocksource for TSC."

Follow this for Xen as well. Looking at its patch context made me notice
they have a pre-existing quirk for Bay Trail as well. The comment there,
however, points at a Cherry Trail document. Looking at the datasheets of
both, there appear to be similar issues, so go beyond Linux'es coverage
and exclude both. Also key the disable on the PCI IDs of the actual
affected devices, rather than those of 00:00.0.

Apply the workarounds only when the use of HPET was not explicitly
requested on the command line and when use of (deep) C-states was not
disabled.

Adjust a few types in touched or nearby code at the same time.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-03 14:14:44 +01:00
Jan Beulich 921f1f4226 gnttab: make sure grant map operations don't skip their IOMMU part
Two almost simultaneous mapping requests need to make sure that at the
completion of the earlier one IOMMU mappings (established explicitly
here in the PV case) have been put in place. Forever since the splitting
of the grant table lock a violation of this has been possible (using
simplified pin counts, as it doesn't matter whether we talk about read
or write mappings here):

initial state: act->pin = 0

vCPU A: progress the operation past the dropping of the locks after the
        act->pin updates (act->pin = 1, old_pin = 0, act_pin = 1)

vCPU B: progress the operation past the dropping of the locks after the
        act->pin updates (act->pin = 2, old_pin = 1, act_pin = 2)

vCPU B: (re-)acquire both gt locks, mapkind() returns 0, but both
        iommu_legacy_map() invocations get skipped due to non-zero
        old_pin

vCPU B: return to caller without IOMMU mapping

vCPU A: (re-)acquire both gt locks, mapkind() returns 0,
        iommu_legacy_map() gets invoked

With the locks dropped intermediately, whether to invoke
iommu_legacy_map() must depend on only the return value of mapkind()
and of course the kind of mapping request being processed, just like
is already the case in unmap_common().

Also fix the style of the adjacent comment, and correct a nearby one
still referring to a prior name of what is now mapkind().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-12-03 14:13:40 +01:00
Jan Beulich d0d72e60f5 x86: fix clang .macro retention check
There were two problems here: The first closing parentheses got parsed
by make to end the $(call invocation, and the escaping of the quotes
wasn't right either, as there's nowhere they would get un-escaped.

Furthermore there appears to be a puzzling problem with \n getting
expanded to an actual newline too early in some environments. Convert
these to semicolons at the same time.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Roger Pau Monné <roger.pau@citrix.com> [On FreeBSD and Debian 9.5]
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-11-29 17:10:00 +01:00
Jan Beulich 0ef3ad9712 console: avoid buffer overrun in guest_console_write()
conring_puts() has been requiring a nul-terminated string, which the
local kbuf[] doesn't get set for anymore. Add a length parameter to the
function, just like was done for others, thus allowing embedded nul to
also be read through XEN_SYSCTL_readconsole.

While there drop a stray cast: Both operands of - are already uint32_t.

Fixes: ea601ec999 ("xen/console: Rework HYPERCALL_console_io interface")
Reported-by: Jürgen Groß <jgross@suse.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <julien@xen.org>
2019-11-29 17:09:16 +01:00
Jan Beulich aaf8839fdf console: avoid buffer overflow in guest_console_write()
The switch of guest_console_write()'s second parameter from plain to
unsigned int has caused the function's main loop header to no longer
guard the min_t() use within the function against effectively negative
values, due to the casts hidden inside the macro. Replace by a plain
min(), casting one of the arguments as necessary.

Fixes: ea601ec999 ("xen/console: Rework HYPERCALL_console_io interface")
Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Julien Grall <julien@xen.org>
2019-11-29 17:08:20 +01:00
Jan Beulich 81ecb38b83 build: provide option to disambiguate symbol names
The .file assembler directives generated by the compiler do not include
any path components (gcc) or just the ones specified on the command line
(clang, at least version 5), and hence multiple identically named source
files (in different directories) may produce identically named static
symbols (in their kallsyms representation). The binary diffing algorithm
used by xen-livepatch, however, depends on having unique symbols.

Make the ENFORCE_UNIQUE_SYMBOLS Kconfig option control the (build)
behavior, and if enabled use objcopy to prepend the (relative to the
xen/ subdirectory) path to the compiler invoked STT_FILE symbols. Note
that this build option is made no longer depend on LIVEPATCH, but merely
defaults to its setting now.

Conditionalize explicit .file directive insertion in C files where it
exists just to disambiguate names in a less generic manner; note that
at the same time the redundant emission of STT_FILE symbols gets
suppressed for clang. Assembler files as well as multiply compiled C
ones using __OBJECT_FILE__ are left alone for the time being.

Since we now expect there not to be any duplicates anymore, also don't
force the selection of the option to 'n' anymore in allrandom.config.
Similarly COVERAGE no longer suppresses duplicate symbol warnings if
enforcement is in effect, which in turn allows
SUPPRESS_DUPLICATE_SYMBOL_WARNINGS to simply depend on
!ENFORCE_UNIQUE_SYMBOLS.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Wei Liu <wl@xen.org>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Tested-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-11-28 17:47:25 +01:00
Jan Beulich 5655ce8b1e x86/IRQ: make internally used IRQs also honor the pending EOI stack
At the time the pending EOI stack was introduced there were no
internally used IRQs which would have the LAPIC EOI issued from the
->end() hook. This had then changed with the introduction of IOMMUs,
but the interaction issue was presumably masked by
irq_guest_eoi_timer_fn() frequently EOI-ing interrupts way too early
(which got fixed by 359cf6f8a0 ["x86/IRQ: don't keep EOI timer
running without need"]).

The problem is that with us re-enabling interrupts across handler
invocation, a higher priority (guest) interrupt may trigger while
handling a lower priority (internal) one. The EOI issued from
->end() (for ACKTYPE_EOI kind interrupts) would then mistakenly
EOI the higher priority (guest) interrupt, breaking (among other
things) pending EOI stack logic's assumptions.

Notes:

- In principle we could get away without the check_eoi_deferral flag.
  I've introduced it just to make sure there's as little change as
  possible to unaffected paths.
- Similarly the cpu_has_pending_apic_eoi() check in do_IRQ() isn't
  strictly necessary.
- The new function's name isn't very helpful with its use in
  end_level_ioapic_irq_new(). I did also consider eoi_APIC_irq() (to
  parallel ack_APIC_irq()), but then liked this even less.

Reported-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Diagnosed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-11-28 15:14:03 +01:00
Jan Beulich 5530782cfe EFI: fix "efi=attr=" handling
Commit 633a409473 ("docs: Improve documentation and parsing for efi=")
failed to honor the strcmp()-like return value convention of
cmdline_strcmp().

Reported-by: Roman Shaposhnik <roman@zededa.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-11-26 14:17:45 +01:00
Jan Beulich 3f1a53bef8 x86/p2m-pt: fix (latent) page table mapping leak on do_recalc() error paths
There are two mappings active in the middle of do_recalc(), and hence
commit 0d0f4d78e5 ("p2m: change write_p2m_entry to return an error
code") should have added (or otherwise invoked) unmapping code just
like it did in p2m_next_level(), despite us not expecting any errors
here. Arrange for the existing unmap invocation to take effect in all
cases.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-11-26 14:17:11 +01:00
Jan Beulich ba2ab00bbb IOMMU: default to always quarantining PCI devices
XSA-302 relies on the use of libxl's "assignable-add" feature to prepare
devices to be assigned to untrusted guests.

Unfortunately, this is not considered a strictly required step for
device assignment. The PCI passthrough documentation on the wiki
describes alternate ways of preparing devices for assignment, and
libvirt uses its own ways as well. Hosts where these alternate methods
are used will still leave the system in a vulnerable state after the
device comes back from a guest.

Default to always quarantining PCI devices, but provide a command line
option to revert back to prior behavior (such that people who both
sufficiently trust their guests and want to be able to use devices in
Dom0 again after they had been in use by a guest wouldn't need to
"manually" move such devices back from DomIO to Dom0).

This is XSA-306.

Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
2019-11-26 14:15:01 +01:00
Jan Beulich f06d11d5a8 AMD/IOMMU: restore DTE fields in amd_iommu_setup_domain_device()
Commit 1b00c16bdf ("AMD/IOMMU: pre-fill all DTEs right after table
allocation") moved ourselves into a more secure default state, but
didn't take sufficient care to also undo the effects when handing a
previously disabled device back to a(nother) domain. Put the fields
that may have been changed elsewhere back to their intended values
(some fields amd_iommu_disable_domain_device() touches don't
currently get written anywhere else, and hence don't need modifying
here).

Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-11-15 14:17:26 +01:00
Jan Beulich a72c508656 x86emul: 16-bit XBEGIN does not truncate rIP
SDM rev 071 points out this fact explicitly.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-11-15 14:15:31 +01:00
Jan Beulich ad591454f0 AMD/IOMMU: don't needlessly trigger errors/crashes when unmapping a page
Unmapping a page which has never been mapped should be a no-op (note how
it already is in case there was no root page table allocated). There's
in particular no need to grow the number of page table levels in use,
and there's also no need to allocate intermediate page tables except
when needing to split a large page.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-11-12 11:08:34 +01:00
Jan Beulich 93021cbe88 x86/PV: check GDT/LDT limits during emulation
Accesses beyond the LDT limit originating from emulation would trigger
the ASSERT() in pv_map_ldt_shadow_page(). On production builds such
accesses would cause an attempt to promote the touched page (offset from
the present LDT base address) to a segment descriptor one. If this
happens to succeed, guest user mode would be able to elevate its
privileges to that of the guest kernel. This is particularly easy when
there's no LDT at all, in which case the LDT base stored internally to
Xen is simply zero.

Also adjust the ASSERT() that was triggering: It was off by one to
begin with, and for production builds we also better use
ASSERT_UNREACHABLE() instead with suitable recovery code afterwards.

This is XSA-298.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-10-31 16:08:16 +01:00
Jan Beulich 64b5d83460 MAINTAINERS: correct description of M:
Let's reflect reality, its use by add_maintainers.pl / get_maintainer.pl,
as well as what
https://wiki.xenproject.org/wiki/Submitting_Xen_Project_Patches says.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-25 10:40:12 +02:00
Jan Beulich 9633929824 x86: fix off-by-one in is_xen_fixed_mfn()
__2M_rwdata_end marks the first byte after the Xen image, not its last
byte. Subtract 1 to obtain the upper bound to compare against. (Note
that instead switching from <= to < is less desirable, as in principle
__pa() might return rubbish for addresses outside of the Xen image.)

Since the & needs to be dropped from the line in question, also drop it
from the adjacent one.

Reported-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-25 10:38:58 +02:00
Jan Beulich 1b00c16bdf AMD/IOMMU: pre-fill all DTEs right after table allocation
Make sure we don't leave any DTEs unexpected requests through which
would be passed through untranslated. Set V and IV right away (with
all other fields left as zero), relying on the V and/or IV bits
getting cleared only by amd_iommu_set_root_page_table() and
amd_iommu_set_intremap_table() under special pass-through circumstances.
Switch back to initial settings in amd_iommu_disable_domain_device().

Take the liberty and also make the latter function static, constifying
its first parameter at the same time, at this occasion.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-10 09:51:46 +02:00
Jan Beulich 110d762e54 AMD/IOMMU: allow callers to request allocate_buffer() to skip its memset()
The command ring buffer doesn't need clearing up front in any event.
Subsequently we'll also want to avoid clearing the device tables.

While playing with functions signatures replace undue use of fixed width
types at the same time, and extend this to deallocate_buffer() as well.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-10 09:51:12 +02:00
Jan Beulich fd345376a5 AMD/IOMMU: allocate one device table per PCI segment
Having a single device table for all segments can't possibly be right.
(Even worse, the symbol wasn't static despite being used in just one
source file.) Attach the device tables to their respective IVRS mapping
ones.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-10 09:50:00 +02:00
Jan Beulich 89a854301e x86emul: adjust MOVSXD source operand handling
XED commit 1b2fd94425 ("Update MOVSXD to modern behavior") points out
that as of SDM rev 064 MOVSXD is specified to read only 16 bits from
memory (or register) when used without REX.W and with operand size
override. Since the upper 16 bits of the value read won't be used
anyway in this case, make the emulation uniformly follow this more
compatible behavior when not emulating an AMD-like CPU, at the risk
of missing an exception when emulating on/for older hardware (the
boundary at SandyBridge noted in said commit looks questionable - I've
observed the "new" behavior also on Westmere, and a discussion there
lead to Mark finding that even Merom has this behavior already).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-04 17:57:03 +02:00
Jan Beulich 2c9e748729 tools/xen-cpuid: avoid producing bogus output
I was (mistakenly, as - looking at the code - it's clearly not intended
to work) passing the tool "Raw" and "Host" as command line arguments.
Avoid printing just "Raw       " with not even a newline at the end in
such a case. Instead report what wasn't understood by the parsing logic.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-02 13:38:02 +02:00
Jan Beulich c0d87ba91f MAINTAINERS: add tools/misc/xen-cpuid to "X86 ARCHITECTURE"
Along the lines of other x86-specific pieces under tools/.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-10-02 13:37:43 +02:00
Jan Beulich 41fd1009cd IOMMU: add missing HVM check
Fix an unguarded d->arch.hvm access in assign_device().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-10-02 13:36:59 +02:00
Jan Beulich fedd7c073b x86: correct bogus error indicator of cpu_add()
Commit 54ce2db8b8 ("x86/numa: adjust datatypes for node and pxm")
changed this from the -1 (i.e. -EPERM, which was already bogus) that
comes back from setup_node() to NUMA_NO_NODE (0xff). Use a proper error
indicator instead.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-30 15:46:24 +02:00
Jan Beulich 7cc2fe0ddc x86emul: move ARPL #UD check
The #UD for being outside of protected mode gets raised for ARPL only
after having read the memory operand - correct this by moving up the
respective construct.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-30 15:45:16 +02:00
Jan Beulich d5b7d10cb4 ns16550: make PCI device hiding uniform
The difference between pci_hide_device() and pci_ro_device() is that
the former only prevents a device from getting assigned to a guest,
while the latter additionally arranges for Dom0 write attempts to the
device's config space to be ignored/discarded. Whether we want one or
the other certainly doesn't depend on whether the device is in our set
of known devices. All that matters is whether we use a PCI device: Call
pci_ro_device() in any such case.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-29 10:03:56 +01:00
Jan Beulich 322609f9c9 AMD/IOMMU: tidy struct ivrs_mappings
Move the device flags field up into an unused hole, thus shrinking
overall structure size by 8 bytes. Use bool and uint<N>_t as
appropriate. Drop pointless (redundant) initializations.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:03:48 +02:00
Jan Beulich 34a9ef62d3 AMD/IOMMU: restrict interrupt remapping table sizes
There's no point setting up tables with more space than a PCI device can
use. For both MSI and MSI-X we can determine how many interrupts could
be set up at most. Tables allocated during ACPI table parsing, however,
will (for now at least) continue to be set up to have maximum size.

Note that until we would want to use sub-page allocations here there's
no point checking whether both MSI and MSI-X are supported by a device -
an order-0 allocation will fit the dual case in any event, no matter
that the MSI-X vector count may be smaller than the MSI one.

On my Rome system this reduces space needed from just over 1k pages to
about 125.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:02:59 +02:00
Jan Beulich bb038f3116 AMD/IOMMU: replace INTREMAP_ENTRIES
Prepare for the number of entries to not be the maximum possible, by
separating checks against maximum size from ones against actual size.
For caller side simplicity have alloc_intremap_entry() return the
maximum possible value upon allocation failure, rather than the first
just out-of-bounds one.

Have the involved functions already take all the subsequently needed
arguments here already, to reduce code churn in the patch actually
making the allocation size dynamic.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
2019-09-25 16:02:21 +02:00
Jan Beulich 93a7810126 x86/PCI: read maximum MSI vector count early
Rather than doing this every time we set up interrupts for a device
anew (and then in several places) fill this invariant field right after
allocating struct pci_dev.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:01:31 +02:00
Jan Beulich 4e5e40fbd5 AMD/IOMMU: make phantom functions share interrupt remapping tables
Rather than duplicating entries in amd_iommu_msi_msg_update_ire(), share
the tables. This mainly requires some care while freeing them, to avoid
freeing memory blocks twice.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
2019-09-25 16:00:46 +02:00
Jan Beulich d7cfeb7c13 AMD/IOMMU: don't blindly allocate interrupt remapping tables
ACPI tables are free to list far more device coordinates than there are
actual devices. By delaying the table allocations for most cases, and
doing them only when an actual device is known to be present at a given
position, overall memory used for the tables goes down from over 500k
pages to just over 1k (on my system having such ACPI table contents).

Tables continue to get allocated right away for special entries
(IO-APIC, HPET) as well as for alias IDs. While in the former case
that's simply because there may not be any device at a given position,
in the latter case this is to avoid having to introduce ref-counting of
table usage.

The change involves invoking
iterate_ivrs_mappings(amd_iommu_setup_device_table) a second time,
because the function now wants to be able to find PCI devices, which
isn't possible yet when IOMMU setup happens very early during x2APIC
mode setup. In this context amd_iommu_init_interrupt() gets renamed as
well.

The logic adjusting a DTE's interrupt remapping attributes also gets
changed, such that the lack of an IRT would result in target aborted
rather than non-remapped interrupts (should any occur).

Note that for now phantom functions get separate IRTs allocated, as was
the case before.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:00:05 +02:00
Jan Beulich ff22a91b4c ACPI/cpuidle: bump maximum number of power states we support
Commit 4c6cd64519 ("mwait_idle: Skylake Client Support") added a table
with 8 entries, which - together with C0 - rendered the current limit
too low. It should have been accompanied by an increase of the constant;
do this now. Don't bump by too much though, as there are a number of on-
stack arrays which are dimensioned by this constant.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-25 15:53:35 +02:00
Jan Beulich 4f54473d00 SVM: correct CPUID event processing
hvm_monitor_cpuid() expects the input registers, not two of the outputs
(it was this way right from its introduction by commit d05f1eb374
["hvm/svm: implement CPUID events"]).

However, once having made the necessary adjustment, the SVM and VMX
functions are so similar that they should be folded (thus avoiding
further similar asymmetries to get introduced). Use the best of both
worlds by e.g. using "curr" consistently. This then being the only
caller of hvm_check_cpuid_faulting(), fold in that function as well.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Alexandru Isaila <aisaila@bitdefender.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-25 15:51:52 +02:00
Jan Beulich c9c7ac508b libxc/x86: correct overflow avoidance check in AMD CPUID handling
Commit df29d03f1d ("libxc/x86: avoid certain overflows in CPUID APIC ID
adjustments" introduced a one bit too narrow mask when checking whether
multiplying by 1 (in particular in leaf 1) would result in overflow.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 15:50:58 +02:00
Jan Beulich df29d03f1d libxc/x86: avoid certain overflows in CPUID APIC ID adjustments
Recent AMD processors may report up to 128 logical processors in CPUID
leaf 1. Doubling this value produces 0 (which OSes sincerely dislike),
as the respective field is only 8 bits wide. Suppress doubling the value
(and its leaf 0x80000008 counterpart) in such a case.

Note that while there's a similar overflow in intel_xc_cpuid_policy(),
that one is being left alone for now.

Note further that while it was considered to suppress the multiplication
by 2 altogether if the host topology already provides at least one bit
of thread ID within APIC IDs, it was decided to avoid more change here
than really needed at this point.

Also zap leaf 4 (and at the same time leaf 2) EDX output for AMD, as it
should have been from the beginning.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-24 10:50:33 +02:00
Jan Beulich 445891bb8e x86/traps: widen condition for logging top-of-stack
Despite -fno-omit-frame-pointer the compiler may omit the frame pointer,
often for relatively simple leaf functions. (To give a specific example,
the case I've run into this with is _pci_hide_device() and gcc 8.
Interestingly the even more simple neighboring iommu_has_feature() does
get a frame pointer set up, around just a single instruction. But this
may be a result of the size-of-asm() effects discussed elsewhere.)

Log the top-of-stack value if it looks valid _or_ if RIP looks invalid.

Also annotate all stack trace entries with a marker, to indicate their
origin:
R: register state
F: frame pointer based
S: raw stack contents

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-24 10:48:44 +02:00
Jan Beulich 22c419eec6 x86/traps: guard top-of-stack reads
Nothing guarantees that the original frame's stack pointer points at
readable memory. Avoid a (likely nested) crash by attaching exception
recovery to the read (making it a single read at the same time). Don't
even invoke _show_trace() in case of a non-readable top slot.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-24 10:47:53 +02:00
Jan Beulich dffb6c488a x86: PCID is unused when !PV
This allows in particular some streamlining of the TLB flushing code
paths.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-18 15:21:51 +02:00
Jan Beulich 36c357817d x86/CPUID: drop INVPCID dependency on PCID
PCID validly depends on LM, as it can be enabled in Long Mode only.
INVPCID, otoh, can be used not only without PCID enabled, but also
outside of Long Mode altogether. In both cases its functionality is
simply restricted to PCID 0, which is sort of expected as no other PCID
can be activated there.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-18 15:20:00 +02:00
Jan Beulich 24c704fb0c x86/HVM: relax shadow mode check in hvm_set_cr3()
There's no need to re-obtain a page reference if only bits not affecting
the address change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-18 15:19:08 +02:00
Jan Beulich edc426665f x86: limit the amount of TLB flushing in switch_cr3_cr4()
We really need to flush the TLB just once, if we do so with or after the
CR3 write. The only case where two flushes are unavoidable is when we
mean to turn off CR4.PGE (perhaps just temporarily; see the code
comment).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-18 15:14:49 +02:00
Jan Beulich 464409f6cf x86: adjust cr3_pcid() return type
There's no need for it to be 64 bits wide - only the low twelve bits
of CR3 hold the PCID.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-18 15:14:08 +02:00
Jan Beulich 935641add6 x86emul: treat Hygon guests like AMD ones
For some reason the Hygon enabling series left out the insn emulator.
Make appropriate adjustments wherever we've been special casing AMD.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-18 15:13:21 +02:00
Jan Beulich ef265d7551 core-parking: interact with runtime SMT-disabling
When disabling SMT at runtime, secondary threads should no longer be
candidates for bringing back up in response to _PUR ACPI events. Purge
them from the tracking array.

Doing so involves adding locking to guard accounting data in the core
parking code. While adding the declaration for the lock, take the
liberty to drop two unnecessary forward function declarations.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-18 15:12:33 +02:00
Jan Beulich 27ddc58d42 x86/PCI: read MSI-X table entry count early
Rather than doing this every time we set up interrupts for a device
anew (and then in two distinct places) fill this invariant field
right after allocating struct arch_msix.

While at it also obtain the MSI-X capability structure position just
once, in msix_capability_init(), rather than in each caller.

Furthermore take the opportunity and eliminate the multi_msix_capable()
alias of msix_table_size().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-17 16:06:15 +02:00
Jan Beulich 076c34d12a AMD/IOMMU: let callers of amd_iommu_alloc_intremap_table() handle errors
Additional users of the function will want to handle errors more
gracefully. Remove the BUG_ON()s and make the current caller panic()
instead.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-17 16:05:34 +02:00
Jan Beulich 34c0dcf84f AMD/IOMMU: introduce a "valid" flag for IVRS mappings
For us to no longer blindly allocate interrupt remapping tables for
everything the ACPI tables name, we can't use struct ivrs_mappings'
intremap_table field anymore to also have the meaning of "this entry
is valid". Add a separate boolean field instead.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-17 16:05:01 +02:00
Jan Beulich 2ec0c0e13e AMD/IOMMU: don't free shared IRT multiple times
Calling amd_iommu_free_intremap_table() for every IVRS entry is correct
only in per-device-IRT mode. Use a NULL 2nd argument to indicate that
the shared table should be freed, and call the function exactly once in
shared mode.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-17 16:03:44 +02:00
Jan Beulich 8e8ae158c8 x86/shadow: fold p2m page accounting into sh_min_allocation()
This is to make the function live up to the promise its name makes. And
it simplifies all callers.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
2019-09-11 14:54:34 +02:00
Jan Beulich 1835980fc6 x86emul: fix test harness and fuzzer build dependencies
Commit fd35f32b4b ("tools/x86emul: Use struct cpuid_policy in the
userspace test harnesses") didn't account for the dependencies of
cpuid-autogen.h to potentially change between incremental builds. In
particular the harness has a "run" goal which is supposed to be usable
independently of the rest of the tools sub-tree building, and both the
harness and the fuzzer code are also supposed to be buildable
independently. Therefore a re-build of the generated header needs to be
triggered first, which is achieved by introducing a new top-level target
pattern (for just the "run" part for now).

Further cpuid.o did not have any dependencies added for it.

Finally, while at it, add a "run" target to the cpu-policy test harness.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2019-09-10 16:35:09 +02:00
Jan Beulich fba818d400 x86/IRQ: make 'i' debug output more tabular again
Since the affinity values are no longer of uniform width, move them
further to the right such that as much of the output as possible comes
out aligned with one another.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-10 16:34:21 +02:00
Jan Beulich fef9e95ee1 x86: drop CONFIG_X86_MCE_THERMAL
There's no point having this if it's not exposed through Kconfig.

Take the liberty and also drop an unnecessary "return" in context.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-06 17:06:19 +02:00
Jan Beulich fa8f9792be VT-d/ATS: tidy device_in_domain()
Use appropriate types. Drop unnecessary casts. Check for failures which
can (at least in theory because of non-obvious breakage elsewhere)
occur, instead of ones which really can't (map_domain_page() won't
return NULL).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
2019-09-05 10:02:11 +02:00
Jan Beulich aa370d3c26 x86/cpu-policy: work around bogus warning in test harness
Despite %.12s properly limiting the number of characters read from
ident[], gcc 9 (at least up to 9.2.0) warns about the strings not
being nul-terminated:

test-cpu-policy.c:64:18: error: '%.12s' directive argument is not a nul-terminated string [-Werror=format-overflow=]
   64 |             fail("  Test '%.12s', expected vendor %u, got %u\n",
      |                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test-cpu-policy.c:20:12: note: in definition of macro 'fail'
   20 |     printf(fmt, ##__VA_ARGS__);                 \
      |            ^~~
test-cpu-policy.c:64:27: note: format string is defined here
   64 |             fail("  Test '%.12s', expected vendor %u, got %u\n",
      |                           ^~~~~
test-cpu-policy.c:44:7: note: referenced argument declared here
   44 |     } tests[] = {
      |       ^~~~~

The issue was reported against gcc in their bugzilla (bug 91667).

Re-order array entries, oddly enough suppressing the warning.

Reported-by: Christopher Clark <christopher.w.clark@gmail.com>
Reported-by: Dario Faggioli <dfaggioli@suse.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-05 10:00:07 +02:00
Jan Beulich 4067bbfa3b VT-d: avoid PCI device lookup
The two uses of pci_get_pdev_by_domain() lack proper locking, but are
also only used to get hold of a NUMA node ID. Calculate and store the
node ID earlier on and remove the lookups (in lieu of fixing the
locking).

While doing this it became apparent that iommu_alloc()'s use of
alloc_pgtable_maddr() would occur before RHSAs would have been parsed:
iommu_alloc() gets called from the DRHD parsing routine, which - on
spec conforming platforms - happens strictly before RHSA parsing. Defer
the allocation until after all ACPI table parsing has finished,
established the node ID there first.

Suggested-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
2019-09-05 09:58:17 +02:00
Jan Beulich e03eb14548 VT-d: tidy <X>_to_<Y>() functions
Drop iommu_to_drhd() altogether - there's no need for a loop here, the
corresponding DRHD is a field in struct intel_iommu.

Constify drhd_to_rhsa()'s parameter and adjust style.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
2019-09-05 09:57:44 +02:00
Jan Beulich 8b25551baa x86/shadow: don't enable shadow mode with too small a shadow allocation (part 2)
Commit 2634b997af ("x86/shadow: don't enable shadow mode with too small
a shadow allocation") was incomplete: The adjustment done there to
shadow_enable() is also needed in shadow_one_bit_enable(). The (new)
problem report was (apparently) a failed PV guest migration followed by
another migration attempt for that same guest. Disabling log-dirty mode
after the first one had left a couple of shadow pages allocated (perhaps
something that also wants fixing), and hence the second enabling of
log-dirty mode wouldn't have allocated anything further.

Reported-by: James Wang <jnwang@suse.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
2019-09-05 09:56:42 +02:00
Jan Beulich 73dad9d966 x86emul: support INVPCID
Just like for INVLPGA the HVM hook only supports PCID 0 for the time
being for individual address invalidation. It also translates the other
types to a full flush, which is architecturally permitted and
performance-wise presumably not much worse because emulation is slow
anyway.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-03 14:50:33 +02:00
Jan Beulich 749c6e3c0e x86emul: generalize invlpg() hook
The hook is already in use for INVLPGA as well. Rename the hook and add
parameters. For the moment INVLPGA with a non-zero ASID remains
unsupported, but the TODO item gets pushed into the actual hook handler.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-03 14:49:52 +02:00
Jan Beulich 4d4fec207b x86/HVM: ignore guest INVD uses
The only place we'd expect the insn to be sensibly used is in
(virtualization unaware) firmware.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-03 14:49:20 +02:00
Jan Beulich ad3abc47dd x86emul: support WBNOINVD
Rev 037 of Intel's ISA extensions document does not state intercept
behavior for the insn (I've been unofficially told that the distinction
is going to be by exit qualification, as I would have assumed
considering that this way it's sufficiently transparent to unaware
software, as using WBINVD in place of WBNOINVD is always correct, just
less efficient). Similarly AMD's PM volume 2 version 3.31 only states
that both use the same VMEXIT, but not how to distinugish them (other
than by decoding the insn). Therefore in the HVM case for now it'll be
backed by the same ->wbinvd_intercept() handlers.

Use this occasion and also add the two missing table entries for
CLDEMOTE, which doesn't require any further changes to make work.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-03 14:48:19 +02:00
Jan Beulich e8e9f4b982 x86: shrink video_{flags,mode} to {8,16} bits
We really don't need them to be any wider.

Also remove the C level declaration (and hence also the GLOBAL) of
video_mode altogether; it's used in assembly code only.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-02 14:45:57 +02:00
Jan Beulich 242d78ae76 x86: a little bit of 16-bit video mode setting code cleanup
To "compensate" for the code size growth by an earlier change:
- drop "trampoline" labels (in almost all cases the target label is
  reachable with an 8-bit-displacement branch anyway, and a single 16-
  bit-displacement branch is still better than a pair of two branches)
- drop an entirely dead insn from wakeup.S:mode_setw
- reduce code size in a few other (obvious I hope) cases, by more
  suitable insn/operands selection

Also drop redundant #define-s (move suitable #include a little earlier
instead) and add two alignment directives.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-02 14:45:18 +02:00
Jan Beulich d1235883bf x86/ACPI: restore VESA mode upon resume from S3
In order for "acpi_sleep=s3_mode" to have any effect, we should record
the video mode we switched to during boot. Since right now there's mode
setting code for VESA modes only in the resume case, record the mode
just in that one case.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-02 14:41:19 +02:00
Jan Beulich 52dba7bd0b x86emul: generalize wbinvd() hook
The hook is already in use for other purposes, and emulating e.g.
CLFLUSH by issuing WBINVD is, well, not very nice. Rename the hook and
add parameters. Use lighter weight flushing insns when possible in
hvmemul_cache_op().

hvmemul_cache_op() treating x86emul_invd the same as x86emul_wbinvd is
to retain original behavior, but I'm not sure this is what we want in
the long run.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Paul Durrant <paul.durrant@citrix.com>
2019-09-02 14:40:15 +02:00
Jan Beulich 7ad6f2a9be timers: limit heap size
First and foremost make timer_softirq_action() avoid growing the heap
if its new size can't be stored without truncation. 64k entries is a
lot, and I don't think we're at risk of actually running into the issue,
but I also think it's better not to allow for hard to debug problems to
occur in the first place.

Furthermore also adjust the code such the size/limit fields becoming
unsigned int would at least work from a mere sizing point of view. For
this also switch various uses of plain int to unsigned int.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-02 14:38:37 +02:00
Jan Beulich 6e2ea60524 x86: move INVPCID_TYPE_* to x86-defns.h
This way the insn emulator can then too use the #define-s. In place of
the TYPE infix add an X86 prefix.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-08-30 15:21:54 +02:00
Jan Beulich eb91201107 x86/ACPI: re-park previously parked CPUs upon resume from S3
Aiui when resuming from S3, CPUs come back out of RESET/INIT. Therefore
they need to undergo the same procedure as was added elsewhere by
commits d8f974f1a6 ("x86: command line option to avoid use of secondary
hyper-threads") and 8797d20a6e ("x86: possibly bring up all CPUs even
if not all are supposed to be used").

Just like done at boot time, avoid (at least pointlessly) using
stop-machine logic.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-08-30 10:24:13 +02:00
Jan Beulich 41c7700a00 x86: properly gate clearing of PKU feature
setup_clear_cpu_cap() is __init and hence may not be called post-boot.
Note that opt_pku nevertheless is not getting __initdata added - see
e.g. commit 43fa95ae6a ("mm: make opt_bootscrub non-init").

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-08-29 15:10:07 +02:00
Jan Beulich 7888440625 x86/xpti: Don't leak TSS-adjacent percpu data via Meltdown
The XPTI work restricted the visibility of most of memory, but missed a few
aspects when it came to the TSS.

Given that the TSS is just an object in percpu data, the 4k mapping for it
created in setup_cpu_root_pgt() maps adjacent percpu data, making it all
leakable via Meltdown, even when XPTI is in use.

Furthermore, no care is taken to check that the TSS doesn't cross a page
boundary.  As it turns out, struct tss_struct is aligned on its size which
does prevent it straddling a page boundary.

Rework the TSS types while making this change.  Rename tss_struct to tss64, to
mirror the existing tss32 structure we have in HVM's Tast Switch logic.  Drop
tss64's alignment and __cacheline_filler[] field.

Introduce tss_page which contains a single tss64 and keeps the rest of the
page clear, so no adjacent data can be leaked.  Move the definition from
setup.c to traps.c, which is a more appropriate place for it to live.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
2019-08-12 14:10:09 +01:00
Jan Beulich 943c598efd x86: define a few selector values
TSS, LDT, and per-CPU entries all can benefit a little from also having
their selector values defined.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-08-09 16:35:42 +02:00
Jan Beulich 99e2326582 AMD/IOMMU: drop stray "else"
The blank line between it and the prior if() clearly indicates that this
was meant to be a standalone if().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-08-07 12:12:00 +02:00