linux.git/drivers/xen, branch v6.7-rc2

xen/events: remove some info_for_irq() calls in pirq handling

2023-11-15T08:51:51+00:00

Instead of the IRQ number user the struct irq_info pointer as parameter
in the internal pirq related functions. This allows to drop some calls
of info_for_irq().

Signed-off-by: Juergen Gross 
Reviewed-by: Oleksandr Tyshchenko 
Signed-off-by: Juergen Gross

xen/events: modify internal [un]bind interfaces

2023-11-15T08:29:39+00:00

Modify the internal bind- and unbind-interfaces to take a struct
irq_info parameter. When allocating a new IRQ pass the pointer from
the allocating function further up.

This will reduce the number of info_for_irq() calls and make the code
more efficient.

Signed-off-by: Juergen Gross 
Reviewed-by: Oleksandr Tyshchenko 
Signed-off-by: Juergen Gross

xen/events: drop xen_allocate_irqs_dynamic()

2023-11-15T08:02:59+00:00

Instead of having a common function for allocating a single IRQ or a
consecutive number of IRQs, split up the functionality into the callers
of xen_allocate_irqs_dynamic().

This allows to handle any allocation error in xen_irq_init() gracefully
instead of panicing the system. Let xen_irq_init() return the irq_info
pointer or NULL in case of an allocation error.

Additionally set the IRQ into irq_info already at allocation time, as
otherwise the IRQ would be '0' (which is a valid IRQ number) until
being set.

Signed-off-by: Juergen Gross 
Reviewed-by: Oleksandr Tyshchenko 
Signed-off-by: Juergen Gross

xen/events: remove some simple helpers from events_base.c

2023-11-14T09:16:34+00:00

The helper functions type_from_irq() and cpu_from_irq() are just one
line functions used only internally.

Open code them where needed. At the same time modify and rename
get_evtchn_to_irq() to return a struct irq_info instead of the IRQ
number.

Signed-off-by: Juergen Gross 
Reviewed-by: Oleksandr Tyshchenko 
Signed-off-by: Juergen Gross

xen/events: reduce externally visible helper functions

2023-11-14T08:29:28+00:00

get_evtchn_to_irq() has only one external user while irq_from_evtchn()
provides the same functionality and is exported for a wider user base.
Modify the only external user of get_evtchn_to_irq() to use
irq_from_evtchn() instead and make get_evtchn_to_irq() static.

evtchn_from_irq() and irq_from_virq() have a single external user and
can easily be combined to a new helper irq_evtchn_from_virq() allowing
to drop irq_from_virq() and to make evtchn_from_irq() static.

Signed-off-by: Juergen Gross 
Reviewed-by: Oleksandr Tyshchenko 
Signed-off-by: Juergen Gross

xen/events: remove unused functions

2023-11-13T14:45:20+00:00

There are no users of xen_irq_from_pirq() and xen_set_irq_pending().

Remove those functions.

Signed-off-by: Juergen Gross 
Reviewed-by: Oleksandr Tyshchenko 
Signed-off-by: Juergen Gross

xen/events: fix delayed eoi list handling

2023-11-13T14:21:08+00:00

When delaying eoi handling of events, the related elements are queued
into the percpu lateeoi list. In case the list isn't empty, the
elements should be sorted by the time when eoi handling is to happen.

Unfortunately a new element will never be queued at the start of the
list, even if it has a handling time lower than all other list
elements.

Fix that by handling that case the same way as for an empty list.

Fixes: e99502f76271 ("xen/events: defer eoi in case of excessive number of events")
Reported-by: Jan Beulich 
Signed-off-by: Juergen Gross 
Reviewed-by: Oleksandr Tyshchenko 
Signed-off-by: Juergen Gross

xen/shbuf: eliminate 17 kernel-doc warnings

2023-11-13T07:14:42+00:00

Don't use kernel-doc markers ("/**") for comments that are not in
kernel-doc format. This prevents multiple kernel-doc warnings:

xen-front-pgdir-shbuf.c:25: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * This structure represents the structure of a shared page
xen-front-pgdir-shbuf.c:37: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Shared buffer ops which are differently implemented
xen-front-pgdir-shbuf.c:65: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Get granted reference to the very first page of the
xen-front-pgdir-shbuf.c:85: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Map granted references of the shared buffer.
xen-front-pgdir-shbuf.c:106: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Unmap granted references of the shared buffer.
xen-front-pgdir-shbuf.c:127: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Free all the resources of the shared buffer.
xen-front-pgdir-shbuf.c:154: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Get the number of pages the page directory consumes itself.
xen-front-pgdir-shbuf.c:164: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Calculate the number of grant references needed to share the buffer
xen-front-pgdir-shbuf.c:176: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Calculate the number of grant references needed to share the buffer
xen-front-pgdir-shbuf.c:194: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Unmap the buffer previously mapped with grant references
xen-front-pgdir-shbuf.c:242: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Map the buffer with grant references provided by the backend.
xen-front-pgdir-shbuf.c:324: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Fill page directory with grant references to the pages of the
xen-front-pgdir-shbuf.c:354: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Fill page directory with grant references to the pages of the
xen-front-pgdir-shbuf.c:393: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Grant references to the frontend's buffer pages.
xen-front-pgdir-shbuf.c:422: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Grant all the references needed to share the buffer.
xen-front-pgdir-shbuf.c:470: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Allocate all required structures to mange shared buffer.
xen-front-pgdir-shbuf.c:510: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Allocate a new instance of a shared buffer.

Signed-off-by: Randy Dunlap 
Reported-by: kernel test robot 
Closes: lore.kernel.org/r/202311060203.yQrpPZhm-lkp@intel.com
Acked-by: Juergen Gross 
Cc: Juergen Gross 
Cc: Stefano Stabellini 
Cc: Oleksandr Tyshchenko 
Cc: xen-devel@lists.xenproject.org
Link: https://lore.kernel.org/r/20231106055631.21520-1-rdunlap@infradead.org
Signed-off-by: Juergen Gross

acpi/processor: sanitize _OSC/_PDC capabilities for Xen dom0

2023-11-13T06:22:00+00:00

The Processor capability bits notify ACPI of the OS capabilities, and
so ACPI can adjust the return of other Processor methods taking the OS
capabilities into account.

When Linux is running as a Xen dom0, the hypervisor is the entity
in charge of processor power management, and hence Xen needs to make
sure the capabilities reported by _OSC/_PDC match the capabilities of
the driver in Xen.

Introduce a small helper to sanitize the buffer when running as Xen
dom0.

When Xen supports HWP, this serves as the equivalent of commit
a21211672c9a ("ACPI / processor: Request native thermal interrupt
handling via _OSC") to avoid SMM crashes.  Xen will set bit
ACPI_PROC_CAP_COLLAB_PROC_PERF (bit 12) in the capability bits and the
_OSC/_PDC call will apply it.

[ jandryuk: Mention Xen HWP's need.  Support _OSC & _PDC ]
Signed-off-by: Roger Pau Monné 
Cc: stable@vger.kernel.org
Signed-off-by: Jason Andryuk 
Reviewed-by: Michal Wilczynski 
Reviewed-by: Juergen Gross 
Link: https://lore.kernel.org/r/20231108212517.72279-1-jandryuk@gmail.com
Signed-off-by: Juergen Gross

xen/events: avoid using info_for_irq() in xen_send_IPI_one()

2023-11-13T06:22:00+00:00

xen_send_IPI_one() is being used by cpuhp_report_idle_dead() after
it calls rcu_report_dead(), meaning that any RCU usage by
xen_send_IPI_one() is a bad idea.

Unfortunately xen_send_IPI_one() is using notify_remote_via_irq()
today, which is using irq_get_chip_data() via info_for_irq(). And
irq_get_chip_data() in turn is using a maple-tree lookup requiring
RCU.

Avoid this problem by caching the ipi event channels in another
percpu variable, allowing the use notify_remote_via_evtchn() in
xen_send_IPI_one().

Fixes: 721255b9826b ("genirq: Use a maple tree for interrupt descriptor management")
Reported-by: David Woodhouse 
Signed-off-by: Juergen Gross 
Tested-by: David Woodhouse 
Acked-by: Stefano Stabellini 
Signed-off-by: Juergen Gross