Commit Graph
46621 Commits
Author SHA1 Message Date
Volodymyr Babchuk 99eeb2eb0b rangeset: add rangeset_purge() function
This function can be used when user wants to remove all rangeset
entries but do not want to destroy rangeset itself.

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2024-02-27 14:56:19 +01:00
Oleksandr Andrushchenko fe62abfcb2 rangeset: add RANGESETF_no_print flag
There are range sets which should not be printed, so introduce a flag
which allows marking those as such. Implement relevant logic to skip
such entries while printing.

While at it also simplify the definition of the flags by directly
defining those without helpers.

Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
2024-02-27 14:55:42 +01:00
Oleksandr Andrushchenko 8c5bca7074 vpci/header: implement guest BAR register handlers
Add relevant vpci register handlers when assigning PCI device to a domain
and remove those when de-assigning. This allows having different
handlers for different domains, e.g. hwdom and other guests.

Emulate guest BAR register values: this allows creating a guest view
of the registers and emulates size and properties probe as it is done
during PCI device enumeration by the guest.

All empty, IO and ROM BARs for guests are emulated by returning 0 on
reads and ignoring writes: this BARs are special with this respect as
their lower bits have special meaning, so returning default ~0 on read
may confuse guest OS.

Introduce is_hwdom convenience variable and convert an existing
is_hardware_domain() check.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
2024-02-27 14:55:15 +01:00
Volodymyr Babchuk e262826159 vpci/header: rework exit path in init_header()
Introduce "fail" label in init_header() function to have the centralized
error return path. This is the pre-requirement for the future changes
in this function.

This patch does not introduce functional changes.

Suggested-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
2024-02-27 14:54:49 +01:00
Oleksandr Andrushchenko f20dde9259 vpci: add hooks for PCI device assign/de-assign
When a PCI device gets assigned/de-assigned we need to
initialize/de-initialize vPCI state for the device.

Also, rename vpci_add_handlers() to vpci_assign_device() and
vpci_remove_device() to vpci_deassign_device() to better reflect role
of the functions.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2024-02-27 14:54:21 +01:00
Oleksandr Andrushchenko 80b0eb095a vpci: restrict unhandled read/write operations for guests
A guest would be able to read and write those registers which are not
emulated and have no respective vPCI handlers, so it will be possible
for it to access the hardware directly.
In order to prevent a guest from reads and writes from/to the unhandled
registers make sure only hardware domain can access the hardware directly
and restrict guests from doing so.

Suggested-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
2024-02-27 14:53:50 +01:00
Oleksandr Andrushchenko 4f78438b45 vpci: use per-domain PCI lock to protect vpci structure
Use the per-domain PCI read/write lock to protect the presence of the
pci device vpci field. This lock can be used (and in a few cases is used
right away) so that vpci removal can be performed while holding the lock
in write mode. Previously such removal could race with vpci_read for
example.

When taking both d->pci_lock and pdev->vpci->lock, they should be
taken in this exact order: d->pci_lock then pdev->vpci->lock to avoid
possible deadlock situations.

1. Per-domain's pci_lock is used to protect pdev->vpci structure
from being removed.

2. Writing the command register and ROM BAR register may trigger
modify_bars to run, which in turn may access multiple pdevs while
checking for the existing BAR's overlap. The overlapping check, if
done under the read lock, requires vpci->lock to be acquired on both
devices being compared, which may produce a deadlock. It is not
possible to upgrade read lock to write lock in such a case. So, in
order to prevent the deadlock, use d->pci_lock in write mode instead.

All other code, which doesn't lead to pdev->vpci destruction and does
not access multiple pdevs at the same time, can still use a
combination of the read lock and pdev->vpci->lock.

3. Drop const qualifier where the new rwlock is used and this is
appropriate.

4. Do not call process_pending_softirqs with any locks held. For that
unlock prior the call and re-acquire the locks after. After
re-acquiring the lock there is no need to check if pdev->vpci exists:
 - in apply_map because of the context it is called (no race condition
   possible)
 - for MSI/MSI-X debug code because it is called at the end of
   pdev->vpci access and no further access to pdev->vpci is made

5. Use d->pci_lock around for_each_pdev and pci_get_pdev()
while accessing pdevs in vpci code.

6. Switch vPCI functions to use per-domain pci_lock for ensuring pdevs
do not go away. The vPCI functions call several MSI-related functions
which already have existing non-vPCI callers. Change those MSI-related
functions to allow using either pcidevs_lock() or d->pci_lock for
ensuring pdevs do not go away. Holding d->pci_lock in read mode is
sufficient. Note that this pdev protection mechanism does not protect
other state or critical sections. These MSI-related functions already
have other race condition and state protection mechanims (e.g.
d->event_lock and msixtbl RCU), so we deduce that the use of the global
pcidevs_lock() is to ensure that pdevs do not go away.

7. Introduce wrapper construct, pdev_list_is_read_locked(), for checking
that pdevs do not go away. The purpose of this wrapper is to aid
readability and document the intent of the pdev protection mechanism.

8. When possible, the existing non-vPCI callers of these MSI-related
functions haven't been switched to use the newly introduced per-domain
pci_lock, and will continue to use the global pcidevs_lock(). This is
done to reduce the risk of the new locking scheme introducing
regressions. Those users will be adjusted in due time. One exception
is where the pcidevs_lock() in allocate_and_map_msi_pirq() is moved to
the caller, physdev_map_pirq(): this instance is switched to
read_lock(&d->pci_lock) right away.

Suggested-by: Roger Pau Monné <roger.pau@citrix.com>
Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2024-02-27 14:53:15 +01:00
Jan Beulich cfe3ad6712 x86: re-run exception-from-stub recovery selftests with CET-SS enabled
On the BSP, shadow stacks are enabled only relatively late in the
booting process. They in particular aren't active yet when initcalls are
run. Keep the testing there, but invoke that testing a 2nd time when
shadow stacks are active, to make sure we won't regress that case after
addressing XSA-451.

While touching this code, switch the guard from NDEBUG to CONFIG_DEBUG,
such that IS_ENABLED() can validly be used at the new call site.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2024-02-27 13:49:52 +01:00
Jan Beulich 91f5f7a915 x86: account for shadow stack in exception-from-stub recovery
Dealing with exceptions raised from within emulation stubs involves
discarding return address (replaced by exception related information).
Such discarding of course also requires removing the corresponding entry
from the shadow stack.

Also amend the comment in fixup_exception_return(), to further clarify
why use of ptr[1] can't be an out-of-bounds access.

While touching do_invalid_op() also add a missing fall-through
annotation.

This is CVE-2023-46841 / XSA-451.

Fixes: 209fb9919b ("x86/extable: Adjust extable handling to be shadow stack compatible")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2024-02-27 13:49:22 +01:00
Andrew Cooper 28154a245c x86: document how stub exception recovery works
Describe how it is meant to work, even if one aspect of it will only be
taken care of subsequently.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-27 13:48:48 +01:00
Jens Wiklander 7356bb5e47 xen/arm: ffa: reclaim shared memory on guest destroy
When an FF-A enabled guest is destroyed it may leave behind memory
shared with SPs. This memory must be reclaimed before it's reused or an
SP may make changes to memory used by a new unrelated guest. So when the
domain is teared down add FF-A requests to reclaim all remaining shared
memory.

SPs in the secure world are notified using VM_DESTROYED that a guest has
been destroyed. An SP is supposed to relinquish all shared memory to allow
reclaiming the memory. The relinquish operation may need to be delayed if
the shared memory is for instance part of a DMA operation.

The domain reference counter is increased when the first FF-A shared
memory is registered and the counter is decreased again when the last
shared memory is reclaimed. If FF-A shared memory registrations remain
at the end of of ffa_domain_teardown() a timer is set to try to reclaim
the shared memory every second until the memory is reclaimed.

A few minor style fixes with a removed empty line here and an added new
line there.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2024-02-27 11:12:06 +00:00
Roger Pau Monné ca7c872c70 xen: introduce Kconfig function alignment option
And use it to replace CODE_ALIGN in assembly.  This allows to generalize the
way the code alignment gets set across all architectures.

No functional change intended.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Acked-by: Shawn Anastasio <sanastasio@raptorengineering.com>
2024-02-27 10:17:59 +01:00
Maria Celeste Cesario 84b9617c03 xen/ppc: address violations of MISRA C:2012 Rule 11.8
The xen sources contain violations of MISRA C:2012 Rule 11.8 whose
headline states:
"A conversion shall not remove any const, volatile or _Atomic qualification
from the type pointed to by a pointer".

Fix violation by adding missing const qualifier in cast.

Signed-off-by: Maria Celeste Cesario <maria.celeste.cesario@bugseng.com>
Signed-off-by: Simone Ballarin <simone.ballarin@bugseng.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Shawn Anastasio <sanastasio@raptorengineering.com>
2024-02-27 10:16:52 +01:00
Olaf Hering 150e7a4e79 automation: remove bin86/dev86 from tumbleweed image
https://build.opensuse.org/request/show/1126240

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2024-02-27 10:16:35 +01:00
Andrew Cooper 37541208f1 x86/entry: Introduce EFRAME_* constants
restore_all_guest() does a lot of manipulation of the stack after popping the
GPRs, and uses raw %rsp displacements to do so.  Also, almost all entrypaths
use raw %rsp displacements prior to pushing GPRs.

Provide better mnemonics, to aid readability and reduce the chance of errors
when editing.

No functional change.  The resulting binary is identical.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 18:20:27 +00:00
Andrew Cooper 0603a0c092 x86/entry: Simplify expressions in compat_restore_all_guest()
compat_restore_all_guest() already has SPEC_CTRL_EXIT_TO_PV with a documented
requirement for %rsp to be both regs and cpuinfo.

Use the now-normal annotations and simplify the expressions which happen to be
a subtraction of 0.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 18:20:27 +00:00
Andrew Cooper 7d3c91377d x86/entry: Adjustments to "reduce assembly code size of entry points"
Some retroactive review, for if I'd got to the patch in time.

 * The new ASM-friendly BUILD_BUG_ON() should be in a header file.
 * entry_int82() wants the movl->movb treatment too.

Fixes: c144b9e324 ("x86: Reduce assembly code size of entry points")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 18:20:27 +00:00
Andrew Cooper 6f1b280876 docs/sphinx: Start an FAQ, and add Kconfig/CET details
This is long overdue, and we need to start somewhere.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 18:20:27 +00:00
George Dunlap 03fb5f503c nestedsvm: Remove bogus debug message from nestedsvm_check_intercepts
Changeset ef3e8db806 ("x86/hvm: Corrections and improvements to
unhandled vmexit logging") introduced a printk to the default path of
the switch statement in nestedsvm_check_intercepts(), complaining of
an unknown exit reason.

Unfortunately, the "core" switch statement which is meant to handle
all vmexit reasons is in nsvm_vmcb_guest_intercepts_exitcode(); the
switch statement in nestedsvm_check_intercepts() is only meant to
superimpose on top of that some special-casing for how to interaction
between L1 and L0 vmexits.

Remove the printk, and add a comment to prevent future confusion.

Fixes: ef3e8db806 ("x86/hvm: Corrections and improvements to unhandled vmexit logging")

Signed-off-by: George Dunlap <george.dunlap@cloud.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 15:57:56 +00:00
George Dunlap 2beef32b42 xen/hvm: Move other hvm_function_table booleans into the caps bitfield
Moving them all together has several advantages:
 * Collects them all in one part of the struct
 * The `caps` field means that we can drop the "_supported" suffix, as it's
   clear what is meant.

While here, replace some 0/1 values with false/true.

Signed-off-by: George Dunlap <george.dunlap@cloud.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 15:57:56 +00:00
George Dunlap 42b8e78b37 svm: Improve type of cpu_has_svm_feature
The "effective type" of the cpu_has_svm_feature macro is effectively
an unsigned log with one bit set (or not); at least one place someone
felt compelled to do a !! to make sure that they got a boolean out of
it.

Ideally the whole of this would be folded into the cpufeature.h
infrastructure.  But for now, duplicate the more type-safe static
inlines in that file, and remove the !!.

Signed-off-by: George Dunlap <george.dunlap@cloud.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 15:57:56 +00:00
George Dunlap 5cd5e3070b xen/hvm: Convert hap_capabilities into a bitfield
hvm_function_table is an internal structure; rather than manually
|-ing and &-ing bits, just make it a boolean bitfield and let the
compiler do all the work.  This makes everything easier to read, and
presumably allows the compiler more flexibility in producing efficient
code.

No functional change intended.

Signed-off-by: George Dunlap <george.dunlap@cloud.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 15:57:56 +00:00
Roger Pau Monné 60e00f77a5 x86/spec: fix BRANCH_HARDEN option to only be set when build-enabled
The current logic to handle the BRANCH_HARDEN option will report it as enabled
even when build-time disabled. Fix this by only allowing the option to be set
when support for it is built into Xen.

Fixes: 2d6f36daa0 ('x86/nospec: Introduce CONFIG_SPECULATIVE_HARDEN_BRANCH')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 16:06:42 +01:00
Anthony PERARD 21051291ad automation: Rework "build-each-commit-gcc" test
Current issues with this test are:
- when the job timeout, the log file is lost as there is no chance to
  run the `mv` command.
- GitLab job log is limited in size, so one usually have to download
  the artifacts, which may be missing.

Use $GITLAB_CI to detect when the script is run as part of a GitLab
pipeline. GitLab will add "GITLAB_CI=true" in the environment
variables.

When run as part of $GITLAB_CI, ignore "dirty" worktree to allow to
write "build-each-commit-gcc.log", which can then be grabbed as
artifacts, even when the job timeout. The `git clean` command is
changed to keep those build logs.

When run as part of $GITLAB_CI, we will also store the build output in
a log file instead of writing it to stdout, because GitLab's job log
is limited. But we will write the log to stdout in case of error, so
we can find out more quickly why there's been an error.

This patch also make use of a GitLab feature, "log sections", which we
will collapse by default. One section per commit been built.

There's a bit of colour added to the logs.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2024-02-26 16:05:59 +01:00
Jan Beulich 56a9641359 x86: Dom0 "broken ELF" reporting adjustments
elf_load_binary() isn't the primary source of brokenness being
indicated. Therefore make the respective PVH log message there
conditional (much like PV has it), and add another instance when
elf_xen_parse() failed (again matching behavior in the PV case).

Make the PV side match the (new) use of %pd here.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2024-02-26 16:04:45 +01:00
Jan Beulich 164daecb18 x86/HVM: limit upcall vector related verbosity
Avoid logging all-identical messages for every vCPU, but make sure to
log unusual events like the vector differing from vCPU 0's (note that
the respective condition also makes sure vCPU 0 itself will have the
vector setting logged), or it changing after it was once set. (Arguably
a downside is that some vCPU not having its vector set would no longer
be recognizable from the logs. But I think that's tolerable as
sufficiently unlikely outside of people actively fiddling with related
code.)

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2024-02-26 16:03:44 +01:00
Oleksii Kurochko 8de3afc0b4 xen: move BUG_ON(), WARN_ON(), ASSERT(), ASSERT_UNREACHABLE() to xen/bug.h
Move the macros mentioned in the commit subject to their appropriate
locations.
Additionally, eliminate the dependency of xen/lib.h from xen/bug.h and
include "xen/bug.h" in files where xen/bug.h macros are utilized.

Most of the changes were made because a file requires macros from xen/bug.h,
except for some files for Arm which require definitions of BUG_OPCODE,
BUG_INSTR, BUG_FN_REG.

xen/lib.h was added to list-sort.c ( otherwise compilation errors related
to {d}printk occur during compilation of list-sort.c. ) as xen/lib.h was
removed from xen/list.h. Since nothing in xen/list.h depends on xen/lib.h
functionality and only xen/bug.h is needed.

cpufeature.h requires the inclusion of <xen/cache.h>;
otherwise, the following error will occur:
ld: common/monitor.o:/build/xen/./arch/x86/include/asm/cpufeature.h:41:
multiple definitions of `__cacheline_aligned';

Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2024-02-26 10:19:08 +01:00
Roger Pau Monné 2ce562b2a4 x86/altcall: use a union as register type for function parameters on clang
The current code for alternative calls uses the caller parameter types as the
types for the register variables that serve as function parameters:

uint8_t foo;
[...]
alternative_call(myfunc, foo);

Would expand roughly into:

register unint8_t a1_ asm("rdi") = foo;
register unsigned long a2_ asm("rsi");
[...]
asm volatile ("call *%c[addr](%%rip)"...);

However with -O2 clang will generate incorrect code, given the following
example:

unsigned int func(uint8_t t)
{
    return t;
}

static void bar(uint8_t b)
{
    int ret_;
    register uint8_t di asm("rdi") = b;
    register unsigned long si asm("rsi");
    register unsigned long dx asm("rdx");
    register unsigned long cx asm("rcx");
    register unsigned long r8 asm("r8");
    register unsigned long r9 asm("r9");
    register unsigned long r10 asm("r10");
    register unsigned long r11 asm("r11");

    asm volatile ( "call %c[addr]"
                   : "+r" (di), "=r" (si), "=r" (dx),
                     "=r" (cx), "=r" (r8), "=r" (r9),
                     "=r" (r10), "=r" (r11), "=a" (ret_)
                   : [addr] "i" (&(func)), "g" (func)
                   : "memory" );
}

void foo(unsigned int a)
{
    bar(a);
}

Clang generates the following assembly code:

func:                                   # @func
        movl    %edi, %eax
        retq
foo:                                    # @foo
        callq   func
        retq

Note the truncation of the unsigned int parameter 'a' of foo() to uint8_t when
passed into bar() is lost.  clang doesn't zero extend the parameters in the
callee when required, as the psABI mandates.

The above can be worked around by using a union when defining the register
variables, so that `di` becomes:

register union {
    uint8_t e;
    unsigned long r;
} di asm("rdi") = { .e = b };

Which results in following code generated for `foo()`:

foo:                                    # @foo
        movzbl  %dil, %edi
        callq   func
        retq

So the truncation is not longer lost.  Apply such workaround only when built
with clang.

Reported-by: Matthew Grooms <mgrooms@shrew.net>
Link: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=277200
Link: https://github.com/llvm/llvm-project/issues/12579
Link: https://github.com/llvm/llvm-project/issues/82598
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 10:18:01 +01:00
Roger Pau Monné ef101f5251 xen/cmdline: fix printf format specifier in no_config_param()
'*' sets the width field, which is the minimum number of characters to output,
but what we want in no_config_param() is the precision instead, which is '.*'
as it imposes a maximum limit on the output.

Fixes: 68d757df8d ('x86/pv: Options to disable and/or compile out 32bit PV support')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2024-02-26 10:17:40 +01:00
Nicola Vetrini 001d7fdb55 xen/consoled: drop return value from consoled_guest_rx/tx
These functions never saw a usage of their return value since
they were introduced, so it can be dropped since their usages
violate MISRA C Rule 17.7:
"The value returned by a function having non-void return type shall be used".

No functional change.

Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2024-02-26 10:17:17 +01:00
Jan Beulich f49fb70d3d x86/hpet: use an atomic add instead of a cmpxchg loop
The usage of a cmpxchg loop in hpet_get_channel() is unnecessary, as the same
can be achieved with an atomic increment, which is both simpler to read, and
avoid any need for a loop.

Note there can be a small divergence in the channel returned if next_channel
overflows, but returned channel will always be in the [0, num_hpets_used)
range, and that's fine for the purpose of balancing HPET channels across CPUs.

Signed-of-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
2024-02-26 10:16:56 +01:00
Roger Pau Monné f0622dd4fd xen/livepatch: fix norevert test hook setup typo
The test code has a typo in using LIVEPATCH_APPLY_HOOK() instead of
LIVEPATCH_REVERT_HOOK().

Fixes: 6047104c3c ('livepatch: Add per-function applied/reverted state tracking marker')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
2024-02-26 10:13:46 +01:00
Andrew Cooper 92babc88f6 Revert stubdom+xenstore 9pfs changes
to unblock CI.  It turns out there are still issues in some configurations.

https://gitlab.com/xen-project/xen/-/pipelines/1188660609

This reverts commit f5e1c527d0.
This reverts commit a76f8809f1.
This reverts commit 93892648ff.
This reverts commit 297a2587e6.
This reverts commit 0b761781c4.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
2024-02-23 18:51:10 +00:00
Juergen Gross f5e1c527d0 tools/xenstored: have a single do_control_memreport()
With 9pfs now available in Xenstore-stubdom, there is no reason to
have distinct do_control_memreport() variants for the daemon and the
stubdom implementations.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
2024-02-23 17:43:06 +00:00
Juergen Gross a76f8809f1 tools/xenstored: support complete log capabilities in stubdom
With 9pfs being fully available in Xenstore-stubdom now, there is no
reason to not fully support all logging capabilities in stubdom.

Open the logfile on stubdom only after the 9pfs file system has been
mounted.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2024-02-23 17:43:06 +00:00
Juergen Gross 93892648ff tools/xenstored: add helpers for filename handling
Add some helpers for handling filenames which might need different
implementations between stubdom and daemon environments:

- expansion of relative filenames (those are not really defined today,
  just expand them to be relative to /var/lib/xen/xenstore)
- expansion of xenstore_daemon_rundir() (used e.g. for saving the state
  file in case of live update - needs to be unchanged in the daemon
  case, but should result in /var/lib/xen/xenstore for stubdom)

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
2024-02-23 17:43:06 +00:00
Juergen Gross 297a2587e6 tools/xenstored: mount 9pfs device in stubdom
Mount the 9pfs device in stubdom enabling it to use files.

This has to happen in a worker thread in order to allow the main thread
handling the required Xenstore accesses in parallel.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
2024-02-23 17:43:06 +00:00
Juergen Gross e21d9dbf44 tools: add 9pfs device to xenstore-stubdom
Add a 9pfs device to Xenstore stubdom in order to allow it to do e.g.
logging into a dom0 file.

Use the following parameters for the new device:

- tag = "Xen"
- type = "xen_9pfsd"
- path = "/var/lib/xen/xenstore"
- security-model = "none"

For now don't limit allowed file space or number of files.

Add a new libxl function for adding it similar to the function for
adding the console device.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2024-02-23 17:43:06 +00:00
Juergen Gross 0b761781c4 stubdom: extend xenstore stubdom configs
Extend the config files of the Xenstore stubdoms to include XENBUS
and 9PFRONT items in order to support file based logging.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
2024-02-23 17:43:06 +00:00
Juergen Gross 4287a71f9b tools/xl: support new 9pfs backend xen_9pfsd
Add support for the new 9pfs backend "xen_9pfsd". For this backend type
the tag defaults to "Xen" and the host side path to
"/var/log/xen/guests/<dom-name>".

Do most of the default settings in libxl. Unfortunately the default
path can't easily be set in libxl, as the domain name isn't available
in the related 9pfs specific function.

Settings the defaults in libxl requires to move the sanity checking
of 9pfs parameters from xl to libxl, too.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2024-02-23 17:43:06 +00:00
Juergen Gross ab5a6b5986 tools/libs/light: add backend type for 9pfs PV devices
Make the backend type of 9pfs PV devices configurable. The default is
"qemu" with the related Xenstore backend-side directory being "9pfs".

Add another type "xen_9pfsd" with the related Xenstore backend-side
directory "xen_9pfs".

As additional security features it is possible to specify:
- "max-space" for limiting the maximum space consumed on the filesystem
  in MBs
- "max-files" for limiting the maximum number of files in the
  filesystem
- "max-open-files" for limiting the maximum number of concurrent open
  files

For convenience "auto-delete" is available to let the backend delete the
oldest file of the guest in case otherwise "max-space" or "max-files"
would be violated.

The xen-9pfsd daemon will be started by libxenlight automatically when
the first "xen_9pfs" device is being created.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: George Dunlap <george.dunlap@cloud.com> # Golang bits
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2024-02-23 17:43:06 +00:00
Edwin Török 098d868e52 tools/oxenstored: Make Quota.t pure
Now that we no longer have a hashtable inside we can make Quota.t pure, and
push the mutable update to its callers.  Store.t already had a mutable Quota.t
field.

No functional change.

Signed-off-by: Edwin Török <edwin.torok@cloud.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
2024-02-23 17:43:06 +00:00
Edwin Török b6cf604207 tools/oxenstored: Use Map instead of Hashtbl for quotas
On a stress test running 1000 VMs flamegraphs have shown that
`oxenstored` spends a large amount of time in `Hashtbl.copy` and the GC.

Hashtable complexity:
 * read/write: O(1) average
 * copy: O(domains) -- copying the entire table

Map complexity:
 * read/write: O(log n) worst case
 * copy: O(1) -- a word copy

We always perform at least one 'copy' when processing each xenstore
packet (regardless whether it is a readonly operation or inside a
transaction or not), so the actual complexity per packet is:
  * Hashtbl: O(domains)
  * Map: O(log domains)

Maps are the clear winner, and a better fit for the immutable xenstore
tree.

Signed-off-by: Edwin Török <edwin.torok@cloud.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
2024-02-23 17:43:06 +00:00
Petr Beneš 7e5b662b28 x86/altp2m: p2m_altp2m_get_or_propagate() should honor ap2m->default_access
This patch addresses a behavior discrepancy in the handling of altp2m views,
where upon the creation and subsequent EPT violation, the page access
permissions were incorrectly inherited from the hostp2m instead of respecting
the altp2m default_access.

Previously, when a new altp2m view was established with restrictive
default_access permissions and activated via xc_altp2m_switch_to_view(),
it failed to trigger an event on the first access violation.  This behavior
diverged from the intended mechanism, where the altp2m's default_access
should dictate the initial permissions, ensuring proper event triggering on
access violations.

The correction involves modifying the handling mechanism to respect the
altp2m view's default_access upon its activation, eliminating the need for
setting memory access permissions for the entire altp2m range (e.g. within
xen-access.c).  This change not only aligns the behavior with the expected
access control logic but also results in a significant performance improvement
by reducing the overhead associated with setting memory access permissions
across the altp2m range.

Signed-off-by: Petr Beneš <w1benny@gmail.com>
Acked-by: Tamas K Lengyel <tamas@tklengyel.com>
2024-02-23 17:43:06 +00:00
Andrew Cooper 98e79be5b6 xen/*/asm-offset: Fix bad copy&paste from x86
All architectures have copy&pasted bad logic from x86.

OFFSET() having a trailing semi-colon within the macro expansion can be a
problematic pattern.  It's benign in this case, but fix it anyway.

Perform style fixes for the other macros, and tame the mess of BLANK()
position to be consistent (one BLANK() after each block) so the intermediate
form is legible too.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Shawn Anastasio <sanastasio@raptorengineering.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
2024-02-23 17:43:06 +00:00
Luca Fancellu 812bdc99f4 xen-analysis.py: Accept deviation comment at the end of the line
Implement the in-code suppression comment at the end of the line.
Now it is possible to add a Xen deviaiton comment with the syntax
described in the docs at the end of the line affected by the
violation, to deviate it.

Eclair natively supports it, so the translation for the tool will
be straighforward, but the other tool needs to translate an
occurrence of the tag into a suppressino comment at the end of the
previous line, this will have a corner case where the line number
1 of the file can't be deviated in this way for such tools.

Updated documentation.

Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2024-02-22 16:08:25 +00:00
Luca Fancellu d064b429b6 xen-analysis.py: Substitute only the comment instead of the line
Change the code in tag_database.py to substitute only the SAF-*
comment instead of replacing the line.

Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2024-02-22 16:08:22 +00:00
Luca Fancellu ddd6696fc6 xen-analysis.py: Use named group for tag regex
Use named group for the regex matching a tag identifier, this
is done to ease retrieving the matching group instead of using
an index.

Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2024-02-22 16:08:06 +00:00
Jan Beulich 8c5e4ce145 consolidate do_bug_frame() / bug_fn_t
The type not being used in do_bug_frame() is suspicious. Apparently
that's solely because the type uses a pointer-to-const parameter,
when so far run_in_exception_handler() wanted functions taking pointer-
to-non-const. Expand use of const, in turn requiring common code's
do_bug_frame() as well as [gs]et_irq_regs() to also gain const. This
then brings the former function also closer to the common one, with
Arm's use of vaddr_t remaining as a difference.

While there also replace the bogus use of hard tabs in [gs]et_irq_regs()
(I clearly didn't mean to put it in like this).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Julien Grall <jgrall@amazon.com>
2024-02-22 12:16:55 +01:00
Jan Beulich f75b051f78 x86/APIC: drop regs parameter from direct vector handler functions
The only place it was needed is in the spurious handler, and there we
can use get_irq_regs() instead.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2024-02-22 12:16:17 +01:00