ACPI currently emulates a timeout for semaphores with calls to
down_trylock and sleep. This produces horrible behaviour in terms of
fairness and excessive wakeups. Now that we have a unified semaphore
implementation, adding a real down_trylock is almost trivial.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
This essentially reverts commit 71fc47a9ad
("ACPI: basic initramfs DSDT override support"), because the code simply
isn't ready.
It did ugly things to the init sequence to populate the rootfs image
early, but that just ended up showing other problems with the whole
approach. The fact is, the VFS layer simply isn't initialized this
early, and the relevant ACPI code should either run much later, or this
shouldn't be done at all.
For 2.6.25, we'll just pick the latter option. We can revisit this
concept later if necessary.
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Tilman Schmidt <tilman@imap.cc>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Eric Piel <eric.piel@tremplin-utc.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Markus Gaugusch <dsdt@gaugusch.at>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The raw_pci_read() interface (as the raw_pci_ops->read() before it)
unconditionally fills in a 32-bit integer return value regardless of the
size of the operation requested.
So claiming to take a "void *" is wrong, as is passing in a pointer to
just a byte variable.
Noticed by pageexec when enabling -fstack-protector (which needs other
patches too to actually work, but that's a separate issue).
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We want to allow different implementations of pci_raw_ops for standard
and extended config space on x86. Rather than clutter generic code with
knowledge of this, we make pci_raw_ops private to x86 and use it to
implement the new raw interface -- raw_pci_read() and raw_pci_write().
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The acpi_no_initrd_override parameter permits to disable the load of an ACPI
table from the initramfs.
Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Len Brown <len.brown@intel.com>
Small ACPICA extension to be able to store the name of operation regions in osl.c later
In ACPI, AML can define accesses to IO ports and System Memory by Operation
Regions. Those are not registered as done by PNPACPI using resource templates
(and _CRS/_SRS methods).
The IO ports and System Memory regions may get accessed by arbitrary AML code.
When native drivers are accessing the same resources bad things can happen
(e.g. a critical shutdown temperature of 3000 C every 2 months or so).
It is not really possible to register the operation regions via
request_resource, as they often overlap with pnp or other resources (e.g.
statically setup IO resources below 0x100).
This approach stores all Operation Region declarations (IO and System Memory
only) at ACPI table parse time. It offers a similar functionality like
request_region and let drivers which are known to possibly use the same IO
ports and Memory which are also often used by ACPI (hwmon and i2c) check for
ACPI interference.
A boot parameter acpi_enforce_resources=strict/lax/no is provided, which
is default set to lax:
- strict: let conflicting drivers fail to load with an error message
- lax: let conflicting driver work normal with a warning message
- no: no functional change at all
Depending on the feedback and the kind of interferences we see, this
should be set to strict at later time.
Goal of this patch set is:
- Identify ACPI interferences in bug reports (very hard to reproduce
and to identify)
- Find BIOSes for that an ACPI driver should exist for specific HW
instead of a native one.
- stability in general
Provide acpi_check_{mem_}region.
Drivers can additionally check against possible ACPI interference by also
invoking this shortly before they call request_region.
If -EBUSY is returned, the driver must not load.
Use acpi_enforce_resources=strict/lax/no options to:
- strict: let conflicting drivers fail to load with an error message
- lax: let conflicting driver work normal with a warning message
- no: no functional change at all
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
