Commit Graph

14 Commits

Author SHA1 Message Date
Ross Lagerwall
410b4d560d xen-hvm: Avoid livelock while handling buffered ioreqs
A malicious or buggy guest may generated buffered ioreqs faster than
QEMU can process them in handle_buffered_iopage(). The result is a
livelock - QEMU continuously processes ioreqs on the main thread without
iterating through the main loop which prevents handling other events,
processing timers, etc. Without QEMU handling other events, it often
results in the guest becoming unsable and makes it difficult to stop the
source of buffered ioreqs.

To avoid this, if we process a full page of buffered ioreqs, stop and
reschedule an immediate timer to continue processing them. This lets
QEMU go back to the main loop and catch up.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-Id: <20240404140833.1557953-1-ross.lagerwall@citrix.com>
Signed-off-by: Anthony PERARD <anthony@xenproject.org>
2024-07-01 14:57:18 +02:00
Edgar E. Iglesias
9ecdd4bf08 xen: mapcache: Add support for grant mappings
Add a second mapcache for grant mappings. The mapcache for
grants needs to work with XC_PAGE_SIZE granularity since
we can't map larger ranges than what has been granted to us.

Like with foreign mappings (xen_memory), machines using grants
are expected to initialize the xen_grants MR and map it
into their address-map accordingly.

CC: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2024-06-09 20:16:14 +02:00
Edgar E. Iglesias
1be974bc26 xen: Add xen_mr_is_memory()
Add xen_mr_is_memory() to abstract away tests for the
xen_memory MR.

No functional changes.

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240529140739.1387692-4-edgar.iglesias@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2024-06-04 11:53:34 +02:00
Paolo Bonzini
0973996fe4 xen: initialize legacy backends from xen_bus_init()
Prepare for moving the calls to xen_be_register() under the
control of xen_bus_init(), using the normal xen_backend_init()
method that is used by the "modern" backends.

This requires the xenstore global variable to be initialized,
which is done by xen_be_init().  To ensure that everything is
ready at the time the xen_backend_init() functions are called,
remove the xen_be_init() function from all the boards and
place it directly in xen_bus_init().

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240509170044.190795-7-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-05-10 15:45:15 +02:00
Philippe Mathieu-Daudé
8570951fcc hw/xen: Use target-agnostic qemu_target_page_bits()
Instead of the target-specific TARGET_PAGE_BITS definition,
use qemu_target_page_bits() which is target agnostic.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20231114143816.71079-15-philmd@linaro.org>
2024-03-09 18:51:45 +01:00
Philippe Mathieu-Daudé
b934c3fa21 hw/xen: Rename 'ram_memory' global variable as 'xen_memory'
To avoid a potential global variable shadow in
hw/i386/pc_piix.c::pc_init1(), rename Xen's
"ram_memory" as "xen_memory".

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20231114143816.71079-11-philmd@linaro.org>
2024-03-09 18:51:45 +01:00
Manos Pitsidianakis
d0e16850ee hw/xen: convert stderr prints to error/warn reports
According to the QEMU Coding Style document:

> Do not use printf(), fprintf() or monitor_printf(). Instead, use
> error_report() or error_vreport() from error-report.h. This ensures the
> error is reported in the right place (current monitor or stderr), and in
> a uniform format.
> Use error_printf() & friends to print additional information.

This commit changes fprintfs that report warnings and errors to the
appropriate report functions.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 42a8953553cf68e8bacada966f93af4fbce45919.1706544115.git.manos.pitsidianakis@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2024-02-02 13:51:59 +00:00
Manos Pitsidianakis
9a1f02a354 hw/xen/xen-hvm-common.c: convert DPRINTF to tracepoints
Tracing DPRINTFs to stderr might not be desired. A developer that relies
on tracepoints should be able to opt-in to each tracepoint and rely on
QEMU's log redirection, instead of stderr by default.

This commit converts DPRINTFs in this file that are used for tracing
into tracepoints.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: b000ab73022dfeb7a7ab0ee8fd0f41fb208adaf0.1706544115.git.manos.pitsidianakis@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2024-02-02 13:51:59 +00:00
Steve Sistare
0f1db069b6 cpus: check running not RUN_STATE_RUNNING
When a vm transitions from running to suspended, runstate notifiers are
not called, so the notifiers still think the vm is running.  Hence, when
we call vm_start to restore the suspended state, we call vm_state_notify
with running=1.  However, some notifiers check for RUN_STATE_RUNNING.
They must check the running boolean instead.

No functional change.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/1704312341-66640-4-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-01-04 09:52:42 +08:00
Peter Maydell
bcb40db010 xen: Don't pass MemoryListener around by value
Coverity points out (CID 1513106, 1513107) that MemoryListener is a
192 byte struct which we are passing around by value.  Switch to
passing a const pointer into xen_register_ioreq() and then to
xen_do_ioreq_register().  We can also make the file-scope
MemoryListener variables const, since nothing changes them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230718101057.1110979-1-peter.maydell@linaro.org>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2023-08-01 10:22:33 +01:00
Isaku Yamahata
5369a36c4f exec/memory: Add symbolic value for memory listener priority for accel
Add MEMORY_LISTNER_PRIORITY_ACCEL for the symbolic value for the memory
listener to replace the hard-coded value 10 for accel.

No functional change intended.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <feebe423becc6e2aa375f59f6abce9a85bc15abb.1687279702.git.isaku.yamahata@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-06-28 14:27:59 +02:00
Vikram Garhwal
6c4193ed16 hw/xen/xen-hvm-common: Use g_new and error_report
Replace g_malloc with g_new and perror with error_report.

Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Paul Durrant <paul@xen.org>
2023-06-15 16:46:28 -07:00
Stefano Stabellini
5ff5c8da94 hw/xen/xen-hvm-common: skip ioreq creation on ioreq registration failure
On ARM it is possible to have a functioning xenpv machine with only the
PV backends and no IOREQ server. If the IOREQ server creation fails continue
to the PV backends initialization.

Also, moved the IOREQ registration and mapping subroutine to new function
xen_do_ioreq_register().

Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Paul Durrant <paul@xen.org>
2023-06-15 16:46:08 -07:00
Stefano Stabellini
f17068c1c7 xen-hvm: reorganize xen-hvm and move common function to xen-hvm-common
This patch does following:
1. creates arch_handle_ioreq() and arch_xen_set_memory(). This is done in
    preparation for moving most of xen-hvm code to an arch-neutral location,
    move the x86-specific portion of xen_set_memory to arch_xen_set_memory.
    Also, move handle_vmport_ioreq to arch_handle_ioreq.

2. Pure code movement: move common functions to hw/xen/xen-hvm-common.c
    Extract common functionalities from hw/i386/xen/xen-hvm.c and move them to
    hw/xen/xen-hvm-common.c. These common functions are useful for creating
    an IOREQ server.

    xen_hvm_init_pc() contains the architecture independent code for creating
    and mapping a IOREQ server, connecting memory and IO listeners, initializing
    a xen bus and registering backends. Moved this common xen code to a new
    function xen_register_ioreq() which can be used by both x86 and ARM machines.

    Following functions are moved to hw/xen/xen-hvm-common.c:
        xen_vcpu_eport(), xen_vcpu_ioreq(), xen_ram_alloc(), xen_set_memory(),
        xen_region_add(), xen_region_del(), xen_io_add(), xen_io_del(),
        xen_device_realize(), xen_device_unrealize(),
        cpu_get_ioreq_from_shared_memory(), cpu_get_ioreq(), do_inp(),
        do_outp(), rw_phys_req_item(), read_phys_req_item(),
        write_phys_req_item(), cpu_ioreq_pio(), cpu_ioreq_move(),
        cpu_ioreq_config(), handle_ioreq(), handle_buffered_iopage(),
        handle_buffered_io(), cpu_handle_ioreq(), xen_main_loop_prepare(),
        xen_hvm_change_state_handler(), xen_exit_notifier(),
        xen_map_ioreq_server(), destroy_hvm_domain() and
        xen_shutdown_fatal_error()

3. Removed static type from below functions:
    1. xen_region_add()
    2. xen_region_del()
    3. xen_io_add()
    4. xen_io_del()
    5. xen_device_realize()
    6. xen_device_unrealize()
    7. xen_hvm_change_state_handler()
    8. cpu_ioreq_pio()
    9. xen_exit_notifier()

4. Replace TARGET_PAGE_SIZE with XC_PAGE_SIZE to match the page side with Xen.

Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2023-06-15 16:45:59 -07:00