The guest address, raddr, should be unsigned, aka abi_ulong.
The host addresses should be cast via *intptr_t not long.
Drop the inline and fix two other whitespace issues.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230626140250.69572-1-richard.henderson@linaro.org>

Support for execveat syscall was implemented in 55bbe4 and is available
since QEMU 8.0.0. It relies on host execveat, which is widely available
on most of Linux kernels today.

However, this change breaks qemu-user self emulation, if "host" qemu
version is less than 8.0.0. Indeed, it does not implement yet execveat.
This strange use case happens with most of distribution today having
binfmt support.

With a concrete failing example:
$ qemu-x86_64-7.2 qemu-x86_64-8.0 /bin/bash -c /bin/ls
/bin/bash: line 1: /bin/ls: Function not implemented
-> not implemented means execve returned ENOSYS

qemu-user-static 7.2 and 8.0 can be conveniently grabbed from debian
packages qemu-user-static* [1].

One usage of this is running wine-arm64 from linux-x64 (details [2]).
This is by updating qemu embedded in docker image that we ran into this
issue.

The solution to update host qemu is not always possible. Either it's
complicated or ask you to recompile it, or simply is not accessible
(GitLab CI, GitHub Actions). Thus, it could be worth to implement execve
without relying on execveat, which is the goal of this patch.

This patch was tested with example presented in this commit message.

[1] http://ftp.us.debian.org/debian/pool/main/q/qemu/
[1] https://www.linaro.org/blog/emulate-windows-on-arm/



Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Message-Id: <20230705121023.973284-1-pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Based on gcc's nios2.h setting BIGGEST_ALIGNMENT to 32 bits.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Based on gcc's microblaze.h setting BIGGEST_ALIGNMENT to 32 bits.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Be careful not to change linux_dirent64, which is a host structure.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Be careful not to change linux_dirent64, which is a host structure.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

These definitions are in sparc/signal.c.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Untabify and re-indent.
We had a mix of 2, 3, 4, and 8 space indentation.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

* SCSI unit attention fix
* add PCIe devices to s390x emulator
* IDE unplug fix for Xen

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* tag 'for-upstream' of https://gitlab.com/bonzini/qemu

:
  scsi: clear unit attention only for REPORT LUNS commands
  scsi: cleanup scsi_clear_unit_attention()
  scsi: fetch unit attention when creating the request
  kconfig: Add PCIe devices to s390x machines
  hw/ide/piix: properly initialize the BMIBA register

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

scsi_clear_unit_attention() now only handles REPORTED LUNS DATA HAS
CHANGED.

This only happens when we handle REPORT LUNS commands, so let's rename
the function in scsi_clear_reported_luns_changed() and call it only in
scsi_target_emulate_report_luns().

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-ID: <20230712134352.118655-4-sgarzare@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The previous commit moved the unit attention clearing when we create
the request. So now we can clean scsi_clear_unit_attention() to handle
only the case of the REPORT LUNS command: this is the only case in
which a UNIT ATTENTION is cleared without having been reported.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-ID: <20230712134352.118655-3-sgarzare@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Commit 1880ad4f ("virtio-scsi: Batched prepare for cmd reqs") split
calls to scsi_req_new() and scsi_req_enqueue() in the virtio-scsi device.
No ill effects were observed until commit 8cc5583a ("virtio-scsi: Send
"REPORTED LUNS CHANGED" sense data upon disk hotplug events") added a
unit attention that was easy to trigger with device hotplug and
hot-unplug.

Because the two calls were separated, all requests in the batch were
prepared calling scsi_req_new() to report a sense.  The first one
submitted would report the right sense and reset it to NO_SENSE, while
the others reported CHECK_CONDITION with no sense data.  This caused
SCSI errors in Linux.

To solve this issue, let's fetch the unit attention as early as possible
when we prepare the request, so that only the first request in the batch
will use the unit attention SCSIReqOps and the others will not report
CHECK CONDITION.

Fixes: 1880ad4f ("virtio-scsi: Batched prepare for cmd reqs")
Fixes: 8cc5583a ("virtio-scsi: Send "REPORTED LUNS CHANGED" sense data upon disk hotplug events")
Reported-by: Thomas Huth <thuth@redhat.com>
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2176702


Co-developed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-ID: <20230712134352.118655-2-sgarzare@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

It is useful to extend the number of available PCIe devices to KVM guests
for passthrough scenarios and also to expose these models to a different
(big endian) architecture. Introduce a new config PCIE_DEVICES to select
models, Intel Ethernet adapters and one USB controller. These devices all
support MSI-X which is a requirement on s390x as legacy INTx are not
supported.

Cc: Matthew Rosato <mjrosato@linux.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Message-ID: <20230712080146.839113-1-clg@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

According to the 82371FB documentation (82371FB.pdf, 2.3.9. BMIBA-BUS
MASTER INTERFACE BASE ADDRESS REGISTER, April 1997), the register is
32bit wide. To properly reset it to default values, all 32bit need to be
cleared. Bit #0 "Resource Type Indicator (RTE)" needs to be enabled.

The initial change wrote just the lower 8 bit, leaving parts of the "Bus
Master Interface Base Address" address at bit 15:4 unchanged.

Fixes: e6a71ae3 ("Add support for 82371FB (Step A1) and Improved support for 82371SB (Function 1)")

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Reviewed-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20230712074721.14728-1-olaf@aepfle.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Pull request

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* tag 'block-pull-request' of https://gitlab.com/stefanha/qemu

:
  virtio-blk: fix host notifier issues during dataplane start/stop

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

The main loop thread can consume 100% CPU when using --device
virtio-blk-pci,iothread=<iothread>. ppoll() constantly returns but
reading virtqueue host notifiers fails with EAGAIN. The file descriptors
are stale and remain registered with the AioContext because of bugs in
the virtio-blk dataplane start/stop code.

The problem is that the dataplane start/stop code involves drain
operations, which call virtio_blk_drained_begin() and
virtio_blk_drained_end() at points where the host notifier is not
operational:
- In virtio_blk_data_plane_start(), blk_set_aio_context() drains after
  vblk->dataplane_started has been set to true but the host notifier has
  not been attached yet.
- In virtio_blk_data_plane_stop(), blk_drain() and blk_set_aio_context()
  drain after the host notifier has already been detached but with
  vblk->dataplane_started still set to true.

I would like to simplify ->ioeventfd_start/stop() to avoid interactions
with drain entirely, but couldn't find a way to do that. Instead, this
patch accepts the fragile nature of the code and reorders it so that
vblk->dataplane_started is false during drain operations. This way the
virtio_blk_drained_begin() and virtio_blk_drained_end() calls don't
touch the host notifier. The result is that
virtio_blk_data_plane_start() and virtio_blk_data_plane_stop() have
complete control over the host notifier and stale file descriptors are
no longer left in the AioContext.

This patch fixes the 100% CPU consumption in the main loop thread and
correctly moves host notifier processing to the IOThread.

Fixes: 1665d932 ("virtio-blk: implement BlockDevOps->drained_begin()")
Reported-by: Lukáš Doktor <ldoktor@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Lukas Doktor <ldoktor@redhat.com>
Message-id: 20230704151527.193586-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Hi,

"Host Memory Backends" and "Memory devices" queue ("mem"):
- Memory device cleanups (especially around machine initialization)
- "x-ignore-shared" migration support for virtio-mem
- Add an abstract virtio-md-pci device as a common parent for
  virtio-mem-pci and virtio-pmem-pci (virtio based memory devices)
- Device unplug support for virtio-mem-pci

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* tag 'mem-2023-07-12' of https://github.com/davidhildenbrand/qemu

: (21 commits)
  virtio-mem-pci: Device unplug support
  virtio-mem: Prepare for device unplug support
  virtio-md-pci: Support unplug requests for compatible devices
  virtio-md-pci: Handle unplug of virtio based memory devices
  arm/virt: Use virtio-md-pci (un)plug functions
  pc: Factor out (un)plug handling of virtio-md-pci devices
  virtio-md-pci: New parent type for virtio-mem-pci and virtio-pmem-pci
  virtio-mem: Support "x-ignore-shared" migration
  migration/ram: Expose ramblock_is_ignored() as migrate_ram_is_ignored()
  virtio-mem: Skip most of virtio_mem_unplug_all() without plugged memory
  softmmu/physmem: Warn with ram_block_discard_range() on MAP_PRIVATE file mapping
  memory-device: Track used region size in DeviceMemoryState
  memory-device: Refactor memory_device_pre_plug()
  hw/i386/pc: Remove PC_MACHINE_DEVMEM_REGION_SIZE
  hw/i386/acpi-build: Rely on machine->device_memory when building SRAT
  hw/i386/pc: Use machine_memory_devices_init()
  hw/loongarch/virt: Use machine_memory_devices_init()
  hw/ppc/spapr: Use machine_memory_devices_init()
  hw/arm/virt: Use machine_memory_devices_init()
  memory-device: Introduce machine_memory_devices_init()
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Let's support device unplug by forwarding the unplug_request_check()
callback to the virtio-mem device.

Further, disallow changing the requested-size once an unplug request is
pending.

Disallowing requested-size changes handles corner cases such as
(1) pausing the VM (2) requesting device unplug and (3) adjusting the
requested size. If the VM would plug memory (due to the requested size
change) before processing the unplug request, we would be in trouble.

Message-ID: <20230711153445.514112-8-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

In many cases, blindly unplugging a virtio-mem device is problematic. We
can only safely remove a device once:
* The guest is not expecting to be able to read unplugged memory
  (unplugged-inaccessible == on)
* The virtio-mem device does not have memory plugged (size == 0)
* The virtio-mem device does not have outstanding requests to the VM to
  plug memory (requested-size == 0)

So let's add a callback to the virtio-mem device class to check for that.
We'll wire-up virtio-mem-pci next.

Message-ID: <20230711153445.514112-7-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

Let's support unplug requests for virtio-md-pci devices that provide
a unplug_request_check() callback.

We'll wire that up for virtio-mem-pci next.

Message-ID: <20230711153445.514112-6-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

While we fence unplug requests from the outside, the VM can still
trigger unplug of virtio based memory devices, for example, in Linux
doing on a virtio-mem-pci device:
    # echo 0 > /sys/bus/pci/slots/3/power

While doing that is not really expected to work without harming the
guest OS (e.g., removing a virtio-mem device while it still provides
memory), let's make sure that we properly handle it on the QEMU side.

We'll add support for unplugging of virtio-mem devices in some
configurations next.

Message-ID: <20230711153445.514112-5-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

Let's use our new helper functions. Note that virtio-pmem-pci is not
enabled for arm and, therefore, not compiled in.

Message-ID: <20230711153445.514112-4-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

Let's factor out (un)plug handling, to be reused from arm/virt code.

Provide stubs for the case that CONFIG_VIRTIO_MD is not selected because
neither virtio-mem nor virtio-pmem is enabled. While this cannot
currently happen for x86, it will be possible for arm/virt.

Message-ID: <20230711153445.514112-3-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

Let's add a new abstract "virtio memory device" type, and use it as
parent class of virtio-mem-pci and virtio-pmem-pci.

Message-ID: <20230711153445.514112-2-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

To achieve desired "x-ignore-shared" functionality, we should not
discard all RAM when realizing the device and not mess with
preallocation/postcopy when loading device state. In essence, we should
not touch RAM content.

As "x-ignore-shared" gets set after realizing the device, we cannot
rely on that. Let's simply skip discarding of RAM on incoming migration.
Note that virtio_mem_post_load() will call
virtio_mem_restore_unplugged() -- unless "x-ignore-shared" is set. So
once migration finished we'll have a consistent state.

The initial system reset will also not discard any RAM, because
virtio_mem_unplug_all() will not call virtio_mem_unplug_all() when no
memory is plugged (which is the case before loading the device state).

Note that something like VM templating -- see commit b17fbbe5
("migration: allow private destination ram with x-ignore-shared") -- is
currently incompatible with virtio-mem and ram_block_discard_range() will
warn in case a private file mapping is supplied by virtio-mem.

For VM templating with virtio-mem, it makes more sense to either
(a) Create the template without the virtio-mem device and hotplug a
    virtio-mem device to the new VM instances using proper own memory
    backend.
(b) Use a virtio-mem device that doesn't provide any memory in the
    template (requested-size=0) and use private anonymous memory.

Message-ID: <20230706075612.67404-5-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

virtio-mem wants to know whether it should not mess with the RAMBlock
content (e.g., discard RAM, preallocate memory) on incoming migration.

So let's expose that function as migrate_ram_is_ignored() in
migration/misc.h

Message-ID: <20230706075612.67404-4-david@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

Already when starting QEMU we perform one system reset that ends up
triggering virtio_mem_unplug_all() with no actual memory plugged yet.
That, in turn will trigger ram_block_discard_range() and perform some
other actions that are not required in that case.

Let's optimize virtio_mem_unplug_all() for the case that no memory is
plugged. This will be beneficial for x-ignore-shared support as well.

Message-ID: <20230706075612.67404-3-david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

ram_block_discard_range() cannot possibly do the right thing in
MAP_PRIVATE file mappings in the general case.

To achieve the documented semantics, we also have to punch a hole into
the file, possibly messing with other MAP_PRIVATE/MAP_SHARED mappings
of such a file.

For example, using VM templating -- see commit b17fbbe5 ("migration:
allow private destination ram with x-ignore-shared") -- in combination with
any mechanism that relies on discarding of RAM is problematic. This
includes:
* Postcopy live migration
* virtio-balloon inflation/deflation or free-page-reporting
* virtio-mem

So at least warn that there is something possibly dangerous is going on
when using ram_block_discard_range() in these cases.

Message-ID: <20230706075612.67404-2-david@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

Let's avoid iterating over all devices and simply track it in the
DeviceMemoryState.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230623124553.400585-11-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

Let's move memory_device_check_addable() and basic checks out of
memory_device_get_free_addr() directly into memory_device_pre_plug().

Separating basic checks from address assignment is cleaner and
prepares for further changes.

As all memory device users now use memory_devices_init(), and that
function enforces that the size is 0, we can drop the check for an empty
region.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230623124553.400585-10-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

There are no remaining users in the tree. Libvirt never used that
property and a quick internet search revealed no other users.

Further, we renamed that property already in commit f2ffbe2b
("pc: rename "hotplug memory" terminology to "device memory"") without
anybody complaining.

So let's just get rid of it.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Eduardo Habkost <eduardo@habkost.net>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230623124553.400585-9-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>