linux.git/drivers/acpi/scan.c, branch v4.12

ACPI / scan: Fix enumeration for special SPI and I2C devices

2017-06-21T21:14:55+00:00

Commit f406270bf73d ("ACPI / scan: Set the visited flag for all
enumerated devices") caused that two group of special SPI or I2C
devices do not enumerate. SPI and I2C devices are expected to be
enumerated by the SPI and I2C subsystems but change caused that
acpi_bus_attach() marks those devices with acpi_device_set_enumerated().

First group of devices are matched using Device Tree compatible property
with special _HID "PRP0001". Those devices have matched scan handler,
acpi_scan_attach_handler() retuns 1 and acpi_bus_attach() marks them
with acpi_device_set_enumerated().

Second group of devices without valid _HID such as "LNXVIDEO" have
device->pnp.type.platform_id set to zero and change again marks them
with acpi_device_set_enumerated().

Fix this by flagging the SPI and I2C devices during struct acpi_device
object initialization time and let the code in acpi_bus_attach() to go
through the device_attach() and acpi_default_enumeration() path for all
SPI and I2C devices.

Fixes: f406270bf73d (ACPI / scan: Set the visited flag for all enumerated devices)
Signed-off-by: Jarkko Nikula 
Acked-by: Mika Westerberg 
Cc: 4.11+  # 4.11+
Signed-off-by: Rafael J. Wysocki

ACPI/IORT: Ignore all errors except EPROBE_DEFER

2017-05-30T09:31:32+00:00

While deferring the probe of IOMMU masters, xlate and
add_device callbacks called from iort_iommu_configure
can pass back error values like -ENODEV, which means
the IOMMU cannot be connected with that master for real
reasons. Before the IOMMU probe deferral, all such errors
were ignored. Now all those errors are propagated back,
killing the master's probe for such errors. Instead ignore
all the errors except EPROBE_DEFER, which is the only one
of concern and let the master work without IOMMU, thus
restoring the old behavior. Also make explicit that
acpi_dma_configure handles only -EPROBE_DEFER from
iort_iommu_configure.

Fixes: 5a1bb638d567 ("drivers: acpi: Handle IOMMU lookup failure with deferred probing or error")
Signed-off-by: Sricharan R 
Signed-off-by: Joerg Roedel

Merge tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

2017-05-09T22:15:47+00:00

Pull IOMMU updates from Joerg Roedel:

 - code optimizations for the Intel VT-d driver

 - ability to switch off a previously enabled Intel IOMMU

 - support for 'struct iommu_device' for OMAP, Rockchip and Mediatek
   IOMMUs

 - header optimizations for IOMMU core code headers and a few fixes that
   became necessary in other parts of the kernel because of that

 - ACPI/IORT updates and fixes

 - Exynos IOMMU optimizations

 - updates for the IOMMU dma-api code to bring it closer to use per-cpu
   iova caches

 - new command-line option to set default domain type allocated by the
   iommu core code

 - another command line option to allow the Intel IOMMU switched off in
   a tboot environment

 - ARM/SMMU: TLB sync optimisations for SMMUv2, Support for using an
   IDENTITY domain in conjunction with DMA ops, Support for SMR masking,
   Support for 16-bit ASIDs (was previously broken)

 - various other small fixes and improvements

* tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (63 commits)
  soc/qbman: Move dma-mapping.h include to qman_priv.h
  soc/qbman: Fix implicit header dependency now causing build fails
  iommu: Remove trace-events include from iommu.h
  iommu: Remove pci.h include from trace/events/iommu.h
  arm: dma-mapping: Don't override dma_ops in arch_setup_dma_ops()
  ACPI/IORT: Fix CONFIG_IOMMU_API dependency
  iommu/vt-d: Don't print the failure message when booting non-kdump kernel
  iommu: Move report_iommu_fault() to iommu.c
  iommu: Include device.h in iommu.h
  x86, iommu/vt-d: Add an option to disable Intel IOMMU force on
  iommu/arm-smmu: Return IOVA in iova_to_phys when SMMU is bypassed
  iommu/arm-smmu: Correct sid to mask
  iommu/amd: Fix incorrect error handling in amd_iommu_bind_pasid()
  iommu: Make iommu_bus_notifier return NOTIFY_DONE rather than error code
  omap3isp: Remove iommu_group related code
  iommu/omap: Add iommu-group support
  iommu/omap: Make use of 'struct iommu_device'
  iommu/omap: Store iommu_dev pointer in arch_data
  iommu/omap: Move data structures to omap-iommu.h
  iommu/omap: Drop legacy-style device support
  ...

Merge branches 'arm/exynos', 'arm/omap', 'arm/rockchip', 'arm/mediatek', 'arm/smmu', 'arm/core', 'x86/vt-d', 'x86/amd' and 'core' into next

2017-05-04T16:06:17+00:00

drivers: acpi: Handle IOMMU lookup failure with deferred probing or error

2017-04-20T14:31:08+00:00

This is an equivalent to the DT's handling of the iommu master's probe
with deferred probing when the corrsponding iommu is not probed yet.
The lack of a registered IOMMU can be caused by the lack of a driver for
the IOMMU, the IOMMU device probe not having been performed yet, having
been deferred, or having failed.

The first case occurs when the firmware describes the bus master and
IOMMU topology correctly but no device driver exists for the IOMMU yet
or the device driver has not been compiled in. Return NULL, the caller
will configure the device without an IOMMU.

The second and third cases are handled by deferring the probe of the bus
master device which will eventually get reprobed after the IOMMU.

The last case is currently handled by deferring the probe of the bus
master device as well. A mechanism to either configure the bus master
device without an IOMMU or to fail the bus master device probe depending
on whether the IOMMU is optional or mandatory would be a good
enhancement.

Tested-by: Hanjun Guo 
Reviewed-by: Robin Murphy 
[Lorenzo: Added fixes for dma_coherent_mask overflow, acpi_dma_configure
          called multiple times for same device]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sricharan R 
Signed-off-by: Joerg Roedel

ACPI / scan: Avoid enumerating devices more than once

2017-04-19T20:57:04+00:00

acpi_bus_attach() does not check the visited flag for devices that
have been enumerated already and some of them may be enumerated
for multiple times as a result, because some callers of
acpi_bus_scan() don't check the visited flag either.

For this reason, modify acpi_bus_attach() to check the visited flag
and avoid enumerating devices that have already been enumerated.

Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Mika Westerberg 
Reviewed-by: Joey Lee

ACPI / scan: Apply default enumeration to devices with ACPI drivers

2017-04-19T20:56:44+00:00

The current code in acpi_bus_attach() is inconsistent with respect
to device objects with ACPI drivers bound to them, as it allows
ACPI drivers to bind to device objects with existing "physical"
device companions, but it doesn't allow "physical" device objects
to be created for ACPI device objects with ACPI drivers bound to
them.  Thus, in some cases, the outcome depends on the ordering
of events which is confusing at best.

For this reason, modify acpi_bus_attach() to call
acpi_default_enumeration() for device objects with the
pnp.type.platform_id flag set regardless of whether or not
any ACPI drivers are bound to them.

Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Mika Westerberg 
Reviewed-by: Joey Lee

Merge back ACPI namespace scan code changes for v4.12.

2017-04-14T22:22:00+00:00

ACPI / scan: Set the visited flag for all enumerated devices

2017-04-13T02:42:18+00:00

Commit 10c7e20b2ff3 (ACPI / scan: fix enumeration (visited) flags for
bus rescans) attempted to fix a problem with ACPI-based enumerateion
of I2C/SPI devices, but it forgot to ensure that the visited flag
will be set for all of the other enumerated devices, so fix that.

Fixes: 10c7e20b2ff3 (ACPI / scan: fix enumeration (visited) flags for bus rescans)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=194885
Reported-and-tested-by: Kevin Locke 
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Mika Westerberg 
Cc: 4.8+  # 4.8+

ACPI / scan: Drop support for force_remove

2017-04-13T01:51:47+00:00

/sys/firmware/acpi/hotplug/force_remove was presumably added to support
auto offlining in the past. This is, however, inherently dangerous for
some hotplugable resources like memory. The memory offlining fails when
the memory is still in use and cannot be dropped or migrated. If we
ignore the failure we are basically allowing for subtle memory
corruption or a crash.

We have actually noticed the later while hitting BUG() during the memory
hotremove (remove_memory):
	ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
			check_memblock_offlined_cb);
	if (ret)
		BUG();

it took us quite non-trivial time realize that the customer had
force_remove enabled. Even if the BUG was removed here and we could
propagate the error up the call chain it wouldn't help at all because
then we would hit a crash or a memory corruption later and harder to
debug. So force_remove is unfixable for the memory hotremove. We haven't
checked other hotplugable resources to be prone to a similar problems.

Remove the force_remove functionality because it is not fixable currently.
Keep the sysfs file and report an error if somebody tries to enable it.
Encourage users to report about the missing functionality and work with
them with an alternative solution.

Reviewed-by: Lee, Chun-Yi 
Signed-off-by: Michal Hocko 
Signed-off-by: Rafael J. Wysocki