Commit Graph
44087 Commits
Author SHA1 Message Date
Jan Beulich d8f8cb8bdd xl: move freemem()'s "credit expired" loop exit
Move the "credit expired" loop exit to the middle of the loop,
immediately after "return true". This way having reached the goal on the
last iteration would be reported as success to the caller, rather than
as "timed out".

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2022-07-18 17:48:18 +02:00
Juergen Gross 3db29e8fac tools/xenstore: add documentation for extended watch command
Add documentation for an extension of the WATCH command used to limit
the scope of watched paths. Additionally it enables to receive more
information in the events related to special watches (@introduceDomain
or @releaseDomain).

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
2022-07-18 17:47:23 +02:00
Juergen Gross 6574f38779 tools/xenstore: add documentation for new set/get-quota commands
Add documentation for two new Xenstore wire commands SET_QUOTA and
GET_QUOTA used to set or query the Xenstore quota of a given domain.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
2022-07-18 17:47:04 +02:00
Juergen Gross 1a564e4b3b tools/xenstore: add documentation for new set/get-feature commands
Add documentation for two new Xenstore wire commands SET_FEATURE and
GET_FEATURE used to set or query the Xenstore features visible in the
ring page of a given domain.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
2022-07-18 17:46:47 +02:00
Andrew Cooper 660d69cd5a xen/wait: Minor asm improvements
There is no point preserving all registers.  Instead, preserve an arbitrary 6
registers, and list the rest as clobbered.  This does not alter the register
scheduling at all, but does reduce the amount of state needing saving.

Use a named parameter for page size, instead of needing to parse which is
parameter 3.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-18 15:55:53 +01:00
Andrew Cooper d93a8c481c xen/wait: Extend the description of how this logic actually works
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-18 15:55:53 +01:00
Andrew Cooper 7a105f7c76 xen/wait: Drop vestigial remnants of TRAP_regs_partial
The preservation of entry_vector was introduced with ecf9846a6a ("x86:
save/restore only partial register state where possible") where
TRAP_regs_partial was introduced, but missed from f9eb74789a ("x86/entry:
Remove support for partial cpu_user_regs frames") where TRAP_regs_partial was
removed.

Fixes: f9eb74789a ("x86/entry: Remove support for partial cpu_user_regs frames")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-18 15:55:53 +01:00
Andrew Cooper 0af91dc032 xen: Fix latent check-endbr.sh bug with 32bit build environments
While Xen's current VMA means it works, the mawk fix (i.e. using $((0xN)) in
the shell) isn't portable in 32bit shells.  See the code comment for the fix.

The fix found a second latent bug.  Recombining $vma_hi/lo should have used
printf "%s%08x" and only worked previously because $vma_lo had bits set in
it's top nibble.  Combining with the main fix, %08x becomes %07x.

Fixes: b2ebe879a4 ("xen: Fix check-endbr.sh with mawk")
Reported-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-18 15:32:27 +01:00
Anthony PERARD b2ebe879a4 xen: Fix check-endbr.sh with mawk
check-endbr.sh works with gawk, but fails with mawk. The produced $ALL
file is smaller as it is missing 0x$vma_lo on every line.  With mawk,
int(0x2A) just produces 0, instead of the expected value.

The use of hexadecimal-constant in awk is an optional part of the posix
spec, and mawk doesn't seems to implemented.

There is a way to convert an hexadecimal to a number be putting it in a
string, and awk as I understand is supposed to use strtod() to convert
the string to a number when needed. The expression 'int("0x15") + 21'
would produce the expected value in `mawk` but now `gawk` won't convert
the string to a number unless we use the option "--non-decimal-data".

So let's convert the hexadecimal number before using it in the awk
script. The shell as no issue with dealing with hexadecimal-constant so
we'll simply use the expression "$(( 0x15 ))" to convert the value
before using it in awk.

Note: This does introduce a latent portability bug, which fixed in a separate
      change to avoid mixing complexity/explanations.

Fixes: 4d037425dc ("x86: Build check for embedded endbr64 instructions")
Resolves: xen-project/xen#26
Reported-by: Luca Fancellu <Luca.Fancellu@arm.com>
Reported-by: Mathieu Tarral <mathieu.tarral@protonmail.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-07-18 15:31:18 +01:00
Julien Grall a5fb66f451 Revert "xen/arm: mm: Add more ASSERT() in {destroy, modify}_xen_mappings()"
This reverts commit 9b962e6183. This
was committed by mistake (lack an x86 ack).
2022-07-17 14:11:27 +01:00
Julien Grall 9b962e6183 xen/arm: mm: Add more ASSERT() in {destroy, modify}_xen_mappings()
Both destroy_xen_mappings() and modify_xen_mappings() will take in
parameter a range [start, end[. Both end should be page aligned.

Add extra ASSERT() to ensure start and end are page aligned. Take the
opportunity to rename 'v' to 's' to be consistent with the other helper.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>

----
    Changes in v2:
        - Also modify prototype. Note that on x86, the first parameter
          was not matching in the declaration and prototype.
        - Add Bertrand's reviewed-by
2022-07-17 14:10:08 +01:00
Julien Grall 25424d1a6b xen/arm: head: Add missing isb after writing to SCTLR_EL2/HSCTLR
Write to SCTLR_EL2/HSCTLR may not be visible until the next context
synchronization. When initializing the CPU, we want the update to take
effect right now. So add an isb afterwards.

Spec references:
    - AArch64: D13.1.2 ARM DDI 0406C.d
    - AArch32 v8: G8.1.2 ARM DDI 0406C.d
    - AArch32 v7: B5.6.3 ARM DDI 0406C.d

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2022-07-17 14:10:08 +01:00
Julien Grall d07358f2dc xen/arm32: head.S: Introduce a macro to load the physical address of a symbol
A lot of places in the ARM32 assembly requires to load the physical address
of a symbol. Rather than open-coding the translation, introduce a new macro
that will load the phyiscal address of a symbol.

Lastly, use the new macro to replace all the current open-coded version.

Note that most of the comments associated to the code changed have been
removed because the code is now self-explanatory.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2022-07-17 14:10:08 +01:00
Andrew Cooper ab2977b027 README: State POSIX compatibility as a requirement for AWK
In particular, we support FreeBSD and NetBSD build environments, and some
Linux build environments use MAWK over GAWK anyway.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2022-07-15 12:55:16 +01:00
Anthony PERARD f717590f57 xen: Introduce $AWK in check-endbr.sh
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-07-15 12:55:16 +01:00
Xenia Ragiadakou 355caa9ef2 xen/arm: traps: Fix MISRA C 2012 Rule 8.4 violation
Add the function prototype of show_stack() in <asm/processor.h> header file
so that it is visible before its definition in traps.c.

Although show_stack() is referenced only in traps.c, it is declared with
external linkage because, during development, it is often called also by
other files for debugging purposes. Declaring it static would increase
development effort. Add appropriate comment

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2022-07-14 12:07:36 +01:00
Jiamei Xie 6655eb8109 xen/arm: avoid overflow when setting vtimer in context switch
virt_vtimer_save() will calculate the next deadline when the vCPU is
scheduled out. At the moment, Xen will use the following equation:

  virt_timer.cval + virt_time_base.offset - boot_count

The three values are 64-bit and one (cval) is controlled by domain. In
theory, it would be possible that the domain has started a long time
after the system boot. So virt_time_base.offset - boot_count may be a
large numbers.

This means a domain may inadvertently set a cval so the result would
overflow. Consequently, the deadline would be set very far in the
future. This could result to loss of timer interrupts or the vCPU
getting block "forever".

One way to solve the problem, would be to separately
   1) compute when the domain was created in ns
   2) convert cval to ns
   3) Add 1 and 2 together

The first part of the equation never change (the value is set/known at
domain creation). So take the opportunity to store it in domain structure.

Signed-off-by: Jiamei Xie <jiamei.xie@arm.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2022-07-14 12:03:59 +01:00
Andrew Cooper d8cb7e0f06 x86/spec-ctrl: Mitigate Branch Type Confusion when possible
Branch Type Confusion affects AMD/Hygon CPUs on Zen2 and earlier.  To
mitigate, we require SMT safety (STIBP on Zen2, no-SMT on Zen1), and to issue
an IBPB on each entry to Xen, to flush the BTB.

Due to performance concerns, dom0 (which is trusted in most configurations) is
excluded from protections by default.

Therefore:
 * Use STIBP by default on Zen2 too, which now means we want it on by default
   on all hardware supporting STIBP.
 * Break the current IBPB logic out into a new function, extending it with
   IBPB-at-entry logic.
 * Change the existing IBPB-at-ctxt-switch boolean to be tristate, and disable
   it by default when IBPB-at-entry is providing sufficient safety.

If all PV guests on the system are trusted, then it is recommended to boot
with `spec-ctrl=ibpb-entry=no-pv`, as this will provide an additional marginal
perf improvement.

This is part of XSA-407 / CVE-2022-23825.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Andrew Cooper 9deaf2d932 x86/spec-ctrl: Enable Zen2 chickenbit
... as instructed in the Branch Type Confusion whitepaper.

This is part of XSA-407.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-07-12 16:23:00 +01:00
Andrew Cooper 76cb04ad64 x86/cpuid: Enumeration for BTC_NO
BTC_NO indicates that hardware is not succeptable to Branch Type Confusion.

Zen3 CPUs don't suffer BTC.

This is part of XSA-407.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Andrew Cooper 53a570b285 x86/spec-ctrl: Support IBPB-on-entry
We are going to need this to mitigate Branch Type Confusion on AMD/Hygon CPUs,
but as we've talked about using it in other cases too, arrange to support it
generally.  However, this is also very expensive in some cases, so we're going
to want per-domain controls.

Introduce SCF_ist_ibpb and SCF_entry_ibpb controls, adding them to the IST and
DOM masks as appropriate.  Also introduce X86_FEATURE_IBPB_ENTRY_{PV,HVM} to
to patch the code blocks.

For SVM, the STGI is serialising enough to protect against Spectre-v1 attacks,
so no "else lfence" is necessary.  VT-x will use use the MSR host load list,
so doesn't need any code in the VMExit path.

For the IST path, we can't safely check CPL==0 to skip a flush, as we might
have hit an entry path before it's IBPB.  As IST hitting Xen is rare, flush
irrespective of CPL.  A later path, SCF_ist_sc_msr, provides Spectre-v1
safety.

For the PV paths, we know we're interrupting CPL>0, while for the INTR paths,
we can safely check CPL==0.  Only flush when interrupting guest context.

An "else lfence" is needed for safety, but we want to be able to skip it on
unaffected CPUs, so the block wants to be an alternative, which means the
lfence has to be inline rather than UNLIKELY() (the replacement block doesn't
have displacements fixed up for anything other than the first instruction).

As with SPEC_CTRL_ENTRY_FROM_INTR_IST, %rdx is 0 on entry so rely on this to
shrink the logic marginally.  Update the comments to specify this new
dependency.

This is part of XSA-407.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Andrew Cooper e9b8d31981 x86/spec-ctrl: Rework SPEC_CTRL_ENTRY_FROM_INTR_IST
We are shortly going to add a conditional IBPB in this path.

Therefore, we cannot hold spec_ctrl_flags in %eax, and rely on only clobbering
it after we're done with its contents.  %rbx is available for use, and the
more normal register to hold preserved information in.

With %rax freed up, use it instead of %rdx for the RSB tmp register, and for
the adjustment to spec_ctrl_flags.

This leaves no use of %rdx, except as 0 for the upper half of WRMSR.  In
practice, %rdx is 0 from SAVE_ALL on all paths and isn't likely to change in
the foreseeable future, so update the macro entry requirements to state this
dependency.  This marginal optimisation can be revisited if circumstances
change.

No practical change.

This is part of XSA-407.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Andrew Cooper a8e5ef079d x86/spec-ctrl: Rename opt_ibpb to opt_ibpb_ctxt_switch
We are about to introduce the use of IBPB at different points in Xen, making
opt_ibpb ambiguous.  Rename it to opt_ibpb_ctxt_switch.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Andrew Cooper 76d6a36f64 x86/spec-ctrl: Rename SCF_ist_wrmsr to SCF_ist_sc_msr
We are about to introduce SCF_ist_ibpb, at which point SCF_ist_wrmsr becomes
ambiguous.

No functional change.

This is part of XSA-407.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Andrew Cooper 5796912f72 x86/spec-ctrl: Rework spec_ctrl_flags context switching
We are shortly going to need to context switch new bits in both the vcpu and
S3 paths.  Introduce SCF_IST_MASK and SCF_DOM_MASK, and rework d->arch.verw
into d->arch.spec_ctrl_flags to accommodate.

No functional change.

This is part of XSA-407.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Juergen Gross 033ae6f88b xen/build: remove unneeded enumeration in clean-files of xen/include/Makefile
Enumerating a file from $(targets) in $(clean-files) isn't needed.

Remove hypercall-defs.h and headers*.chk from $(clean-files) in
xen/include/Makefile.

Reported-by: Jan Beulich <jbeulich@suse.com>
Fixes: eca1f00d02 ("xen: generate hypercall interface related code")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 15:25:35 +02:00
Juergen Gross 134d53f577 tools/init-xenstore-domain: fix memory map for PVH stubdom
In case of maxmem != memsize the E820 map of the PVH stubdom is wrong,
as it is missing the RAM above memsize.

Additionally the memory map should only specify the Xen special pages
as reserved.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2022-07-12 15:25:20 +02:00
Jan Beulich e58370df76 xl: relax freemem()'s retry calculation
While in principle possible also under other conditions as long as other
parallel operations potentially consuming memory aren't "locked out", in
particular with IOMMU large page mappings used in Dom0 (for PV when in
strict mode; for PVH when not sharing page tables with HAP) ballooning
out of individual pages can actually lead to less free memory available
afterwards. This is because to split a large page, one or more page
table pages are necessary (one per level that is split).

When rebooting a guest I've observed freemem() to fail: A single page
was required to be ballooned out (presumably because of heap
fragmentation in the hypervisor). This ballooning out of a single page
of course went fast, but freemem() then found that it would require to
balloon out another page. This repeating just another time leads to the
function to signal failure to the caller - without having come anywhere
near the designated 30s that the whole process is allowed to not make
any progress at all.

Convert from a simple retry count to actually calculating elapsed time,
subtracting from an initial credit of 30s. Don't go as far as limiting
the "wait_secs" value passed to libxl_wait_for_memory_target(), though.
While this leads to the overall process now possibly taking longer (if
the previous iteration ended very close to the intended 30s), this
compensates to some degree for the value passed really meaning "allowed
to run for this long without making progress".

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2022-07-12 15:25:00 +02:00
George Dunlap a7f006bb31 MAINTAINERS: Make Daniel P. Smith sole XSM maintainer
While mail hasn't been bouncing, Daniel De Graaf has not been
responding to patch submissions or otherwise interacting with the
community for several years.  Daniel Smith has at least been working
with the code, and is a regular member of our community; and he has
agreed to step up into the role.

Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2022-07-12 15:24:30 +02:00
Demi Marie Obenour dc7da0874b EFI: preserve the System Resource Table for dom0
The EFI System Resource Table (ESRT) is necessary for fwupd to identify
firmware updates to install.  According to the UEFI specification §23.4,
the ESRT shall be stored in memory of type EfiBootServicesData.  However,
memory of type EfiBootServicesData is considered general-purpose memory
by Xen, so the ESRT needs to be moved somewhere where Xen will not
overwrite it.  Copy the ESRT to memory of type EfiRuntimeServicesData,
which Xen will not reuse.  dom0 can use the ESRT if (and only if) it is
in memory of type EfiRuntimeServicesData.

Earlier versions of this patch reserved the memory in which the ESRT was
located.  This created awkward alignment problems, and required either
splitting the E820 table or wasting memory.  It also would have required
a new platform op for dom0 to use to indicate if the ESRT is reserved.
By copying the ESRT into EfiRuntimeServicesData memory, the E820 table
does not need to be modified, and dom0 can just check the type of the
memory region containing the ESRT.  The copy is only done if the ESRT is
not already in EfiRuntimeServicesData memory, avoiding memory leaks on
repeated kexec.

See https://lore.kernel.org/xen-devel/20200818184018.GN1679@mail-itl/T/
for details.

Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Tested-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 08:39:19 +02:00
Anthony PERARD d778089ac7 libxl: check return value of libxl__xs_directory in name2bdf
libxl__xs_directory() can potentially return NULL without setting `n`.
As `n` isn't initialised, we need to check libxl__xs_directory()
return value before checking `n`. Otherwise, `n` might be non-zero
with `bdfs` NULL which would lead to a segv.

Fixes: 57bff091f4 ("libxl: add 'name' field to 'libxl_device_pci' in the IDL...")
Reported-by: "G.R." <firemeteor@users.sourceforge.net>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Tested-by: "G.R." <firemeteor@users.sourceforge.net>
2022-07-12 08:38:51 +02:00
Anthony PERARD d693b22733 tools/helpers: fix build of xen-init-dom0 with -Werror
Missing prototype of asprintf() without _GNU_SOURCE.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Henry Wang <Henry.Wang@arm.com>
2022-07-12 08:38:35 +02:00
Anthony PERARD ee38108991 tools/fuzz/libelf: rework makefile
Rename ELF_LIB_OBJS to LIBELF_OBJS as to have the same name as in
libs/guest/.

Replace "-I" by "-iquote".

Remove the use of "vpath". It will not works when we will convert this
makefile to subdirmk. Instead, we create symlinks to the source files.

Since we are creating a new .gitignore for the links, also move the
existing entry to it.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
2022-07-12 08:36:37 +02:00
Andrew Cooper 27357c394b x86/spec-ctrl: Add fine-grained cmdline suboptions for primitives
Support controling the PV/HVM suboption of msr-sc/rsb/md-clear, which
previously wasn't possible.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-11 15:21:35 +01:00
Andrew Cooper 382326cac5 xen/cmdline: Extend parse_boolean() to signal a name match
This will help parsing a sub-option which has boolean and non-boolean options
available.

First, rework 'int val' into 'bool has_neg_prefix'.  This inverts it's value,
but the resulting logic is far easier to follow.

Second, reject anything of the form 'no-$FOO=' which excludes ambiguous
constructs such as 'no-$foo=yes' which have never been valid.

This just leaves the case where everything is otherwise fine, but parse_bool()
can't interpret the provided string.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-11 15:21:35 +01:00
Andrew Cooper 4cdb519d79 x86/spec-ctrl: Honour spec-ctrl=0 for unpriv-mmio sub-option
This was an oversight from when unpriv-mmio was introduced.

Fixes: 8c24b70fed ("x86/spec-ctrl: Add spec-ctrl=unpriv-mmio")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-11 15:21:35 +01:00
Jane Malalane 2ce11ce249 x86/HVM: allow per-domain usage of hardware virtualized APIC
Introduce a new per-domain creation x86 specific flag to
select whether hardware assisted virtualization should be used for
x{2}APIC.

A per-domain option is added to xl in order to select the usage of
x{2}APIC hardware assisted virtualization, as well as a global
configuration option.

Having all APIC interaction exit to Xen for emulation is slow and can
induce much overhead. Hardware can speed up x{2}APIC by decoding the
APIC access and providing a VM exit with a more specific exit reason
than a regular EPT fault or by altogether avoiding a VM exit.

On the other hand, being able to disable x{2}APIC hardware assisted
virtualization can be useful for testing and debugging purposes.

Note:

- vmx_install_vlapic_mapping doesn't require modifications regardless
of whether the guest has "Virtualize APIC accesses" enabled or not,
i.e., setting the APIC_ACCESS_ADDR VMCS field is fine so long as
virtualize_apic_accesses is supported by the CPU.

- Both per-domain and global assisted_x{2}apic options are not part of
the migration stream, unless explicitly set in the respective
configuration files. Default settings of assisted_x{2}apic done
internally by the toolstack, based on host capabilities at create
time, are not migrated.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jane Malalane <jane.malalane@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: "Roger Pau Monné" <roger.pau@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
2022-07-11 12:15:05 +02:00
Jane Malalane 6b2b9b3405 x86: report Interrupt Controller Virtualization capabilities
Add XEN_SYSCTL_PHYSCAP_X86_ASSISTED_XAPIC and
XEN_SYSCTL_PHYSCAP_X86_ASSISTED_X2APIC to report accelerated xAPIC and
x2APIC, on x86 hardware. This is so that xAPIC and x2APIC virtualization
can subsequently be enabled on a per-domain basis.
No such features are currently implemented on AMD hardware.

HW assisted xAPIC virtualization will be reported if HW, at the
minimum, supports virtualize_apic_accesses as this feature alone means
that an access to the APIC page will cause an APIC-access VM exit. An
APIC-access VM exit provides a VMM with information about the access
causing the VM exit, unlike a regular EPT fault, thus simplifying some
internal handling.

HW assisted x2APIC virtualization will be reported if HW supports
virtualize_x2apic_mode and, at least, either apic_reg_virt or
virtual_intr_delivery. This also means that
sysctl follows the conditionals in vmx_vlapic_msr_changed().

For that purpose, also add an arch-specific "capabilities" parameter
to struct xen_sysctl_physinfo.

Note that this interface is intended to be compatible with AMD so that
AVIC support can be introduced in a future patch. Unlike Intel that
has multiple controls for APIC Virtualization, AMD has one global
'AVIC Enable' control bit, so fine-graining of APIC virtualization
control cannot be done on a common interface.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jane Malalane <jane.malalane@citrix.com>
Reviewed-by: "Roger Pau Monné" <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2022-07-11 12:13:59 +02:00
Juergen Gross a58fca51ab docs: add reference to release cycle discussion
As it is coming up basically every release cycle of Xen, add a
reference to the discussion why the current release scheme has been
selected in the release management documentation.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Henry Wang <Henry.Wang@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2022-07-11 12:13:40 +02:00
Anthony PERARD 6899af7609 tools/examples: cleanup Makefile
Don't check if a target exist before installing it. For directory,
install doesn't complain, and for file it would prevent from updating
them. Also remove the existing loop and instead install all files with
a single call to $(INSTALL_DATA).

Remove XEN_CONFIGS-y which isn't used.

Remove "build" target.

Add an empty line after the first comment. The comment isn't about
$(XEN_READMES), it is about the makefile as a whole.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
2022-07-11 12:13:24 +02:00
Anthony PERARD 524cf4da66 tools/console: have one Makefile per program/directory
Sources of both xenconsoled and xenconsole are already separated into
different directory and don't share anything in common. Having two
different Makefile means it's easier to deal with *FLAGS.

Some common changes:
Rename $(BIN) to $(TARGETS), this will be useful later.
Stop removing *.so *.rpm *.a as they aren't created here.
Use $(OBJS-y) to list objects.
Update $(CFLAGS) for the directory rather than a single object.

daemon:
    Remove the need for $(LDLIBS_xenconsoled), use $(LDLIBS) instead.
    Remove the need for $(CONSOLE_CFLAGS-y) and use $(CFLAGS-y)
	instead.

client:
    Remove the unused $(LDLIBS_xenconsole)

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
2022-07-11 12:13:07 +02:00
Juergen Gross 796dae0fe4 xen/x86: remove cf_check attribute from hypercall handlers
Now that the hypercall handlers are all being called directly instead
through a function vector, the "cf_check" attribute can be removed.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Daniel P. Smith <dpsmith@apertussolutions.com> # xsm parts
Acked-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Téo Couprie Diaz <teo.coupriediaz@arm.com>
Acked-by: Dario Faggioli <dfaggioli@suse.com>
2022-07-11 12:11:17 +02:00
Juergen Gross 39fc5f5c02 xen/arm: call hypercall handlers via generated macro
Instead of using a function table use the generated macros for calling
the appropriate hypercall handlers.

This makes the calls of the handlers type safe.

For deprecated hypercalls define stub functions.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Tested-by: Michal Orzel <michal.orzel@arm.com>
2022-07-11 12:09:48 +02:00
Juergen Gross 8523851dbc xen/x86: call hypercall handlers via generated macro
Instead of using a function table use the generated macros for calling
the appropriate hypercall handlers.

This is beneficial to performance and avoids speculation issues.

With calling the handlers using the correct number of parameters now
it is possible to do the parameter register clobbering in the NDEBUG
case after returning from the handler. With the additional generated
data the hard coded hypercall_args_table[] can be replaced by tables
using the generated number of parameters.

Note that this change modifies behavior of clobbering registers in a
minor way: in case a hypercall is returning -ENOSYS (or the unsigned
equivalent thereof) for any reason the parameter registers will no
longer be clobbered. This should be of no real concern, as those cases
ought to be extremely rare and reuse of the registers in those cases
seems rather far fetched.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-11 12:09:13 +02:00
Juergen Gross f9db6bc39d xen: use generated prototypes for hypercall handlers
Remove the hypercall handler's prototypes in the related header files
and use the generated ones instead.

Some handlers having been static before need to be made globally
visible.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
2022-07-11 12:08:03 +02:00
Juergen Gross eca1f00d02 xen: generate hypercall interface related code
Instead of repeating similar data multiple times use a single source
file and a generator script for producing prototypes and call sequences
of the hypercalls.

As the script already knows the number of parameters used add generating
a macro for populating an array with the number of parameters per
hypercall.

The priorities for the specific hypercalls are based on two benchamrks
performed in guests (PV and PVH):

- make -j 4 of the Xen hypervisor (resulting in cpu load with lots of
  processes created)
- scp of a large file to the guest (network load)

With a small additional debug patch applied the number of the
different hypercalls in the guest and in dom0 (for looking at backend
activity related hypercalls) were counted while the benchmark in domU
was running:

PV-hypercall    PV-guest build   PV-guest scp    dom0 build     dom0 scp
mmu_update           186175729           2865         20936        33725
stack_switch           1273311          62381        108589       270764
multicall              2182803             50           302          524
update_va_mapping       571868             10            60           80
xen_version              73061            850           859         5432
grant_table_op               0              0         35557       139110
iret                  75673006         484132        268157       757958
vcpu_op                 453037          71199        138224       334988
set_segment_base       1650249          62387        108645       270823
mmuext_op             11225681            188          7239         3426
sched_op                280153         134645         70729       137943
event_channel_op        192327          66204         71409       214191
physdev_op                   0              0          7721         4315
(the dom0 values are for the guest running the build or scp test, so
dom0 acting as backend)

HVM-hypercall   PVH-guest build    PVH-guest scp
vcpu_op                  277684             2324
event_channel_op         350233            57383
(the related dom0 counter values are in the same range as with the test
running in the PV guest)

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
2022-07-11 12:06:19 +02:00
Juergen Gross e1664942b2 xen: include compat/platform.h from hypercall.h
The definition of compat_platform_op_t is in compat/platform.h
already, so include that file from hypercall.h instead of repeating
the typedef.

This allows to remove the related include statement from
arch/x86/x86_64/platform_hypercall.c.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2022-07-11 11:59:16 +02:00
Juergen Gross 7e21b25059 xen: harmonize return types of hypercall handlers
Today most hypercall handlers have a return type of long, while the
compat ones return an int. There are a few exceptions from that rule,
however.

Get rid of the exceptions by letting compat handlers always return int
and others always return long, with the exception of the Arm specific
physdev_op handler.

For the compat hvm case use eax instead of rax for the stored result as
it should have been from the beginning.

Additionally move some prototypes to include/asm-x86/hypercall.h
as they are x86 specific. Move the compat_platform_op() prototype to
the common header.

Rename paging_domctl_continuation() to do_paging_domctl_cont() and add
a matching define for the associated hypercall.

Make do_callback_op() and compat_callback_op() more similar by adding
the const attribute to compat_callback_op()'s 2nd parameter.

Change the type of the cmd parameter for [do|compat]_kexec_op() to
unsigned int, as this is more appropriate for the compat case.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Christopher Clark <christopher.w.clark@gmail.com> # argo
2022-07-11 11:58:21 +02:00
Juergen Gross 980bfb1ac9 Config.mk: use newest Mini-OS commit
Switch to use the newest Mini-OS commit in order to get the recent
fixes.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2022-07-08 09:42:27 +02:00
Penny Zheng f81fcc3919 update SUPPORT.md for static allocation
SUPPORT.md doesn't seem to explicitly say whether static memory is
supported, so this commit updates SUPPORT.md to add feature static
allocation tech preview for now.

Signed-off-by: Penny Zheng <penny.zheng@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2022-07-08 09:42:14 +02:00