Now move the relevant codes into separate files:
kernel/crash_reserve.c, include/linux/crash_reserve.h.
And add config item CRASH_RESERVE to control its enabling.
And also update the old ifdeffery of CONFIG_CRASH_CORE, including of
<linux/crash_core.h> and config item dependency on CRASH_CORE
accordingly.
And also do renaming as follows:
- arch/xxx/kernel/{crash_core.c => vmcore_info.c}
because they are only related to vmcoreinfo exporting on x86, arm64,
riscv.
And also Remove config item CRASH_CORE, and rely on CONFIG_KEXEC_CORE to
decide if build in crash_core.c.
[yang.lee@linux.alibaba.com: remove duplicated include in vmcore_info.c]
Link: https://lkml.kernel.org/r/20240126005744.16561-1-yang.lee@linux.alibaba.com
Link: https://lkml.kernel.org/r/20240124051254.67105-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pingfan Liu <piliu@redhat.com>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Michael Kelley <mhklinux@outlook.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/8d7d86a24ea36985845c17b6da0933fedbf99ad8.1703693980.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Qemu fw_cfg support was missing for RISC-V, which made it hard to do
proper vmcore dumps from qemu.
Add the missing RISC-V arch-defines.
You can now do vmcore dumps from qemu. Add "-device vmcoreinfo" to the
qemu command-line. From the qemu monitor:
(qemu) dump-guest-memory vmcore
The vmcore can now be used, e.g., with the "crash" utility.
Acked-by: "Michael S. Tsirkin" <mst@redhat.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Clément Léger <cleger@rivosinc.com>
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Message-Id: <20231012102852.234442-1-bjorn@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Here is the large set of char, misc, and other "small" driver subsystem
changes for 5.17-rc1.
Lots of different things are in here for char/misc drivers such as:
- habanalabs driver updates
- mei driver updates
- lkdtm driver updates
- vmw_vmci driver updates
- android binder driver updates
- other small char/misc driver updates
Also smaller driver subsystems have also been updated, including:
- fpga subsystem updates
- iio subsystem updates
- soundwire subsystem updates
- extcon subsystem updates
- gnss subsystem updates
- phy subsystem updates
- coresight subsystem updates
- firmware subsystem updates
- comedi subsystem updates
- mhi subsystem updates
- speakup subsystem updates
- rapidio subsystem updates
- spmi subsystem updates
- virtual driver updates
- counter subsystem updates
Too many individual changes to summarize, the shortlog contains the full
details.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc and other driver updates from Greg KH:
"Here is the large set of char, misc, and other "small" driver
subsystem changes for 5.17-rc1.
Lots of different things are in here for char/misc drivers such as:
- habanalabs driver updates
- mei driver updates
- lkdtm driver updates
- vmw_vmci driver updates
- android binder driver updates
- other small char/misc driver updates
Also smaller driver subsystems have also been updated, including:
- fpga subsystem updates
- iio subsystem updates
- soundwire subsystem updates
- extcon subsystem updates
- gnss subsystem updates
- phy subsystem updates
- coresight subsystem updates
- firmware subsystem updates
- comedi subsystem updates
- mhi subsystem updates
- speakup subsystem updates
- rapidio subsystem updates
- spmi subsystem updates
- virtual driver updates
- counter subsystem updates
Too many individual changes to summarize, the shortlog contains the
full details.
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (406 commits)
counter: 104-quad-8: Fix use-after-free by quad8_irq_handler
dt-bindings: mux: Document mux-states property
dt-bindings: ti-serdes-mux: Add defines for J721S2 SoC
counter: remove old and now unused registration API
counter: ti-eqep: Convert to new counter registration
counter: stm32-lptimer-cnt: Convert to new counter registration
counter: stm32-timer-cnt: Convert to new counter registration
counter: microchip-tcb-capture: Convert to new counter registration
counter: ftm-quaddec: Convert to new counter registration
counter: intel-qep: Convert to new counter registration
counter: interrupt-cnt: Convert to new counter registration
counter: 104-quad-8: Convert to new counter registration
counter: Update documentation for new counter registration functions
counter: Provide alternative counter registration functions
counter: stm32-timer-cnt: Convert to counter_priv() wrapper
counter: stm32-lptimer-cnt: Convert to counter_priv() wrapper
counter: ti-eqep: Convert to counter_priv() wrapper
counter: ftm-quaddec: Convert to counter_priv() wrapper
counter: intel-qep: Convert to counter_priv() wrapper
counter: microchip-tcb-capture: Convert to counter_priv() wrapper
...
There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field. Move the firmware qemu_fw_cfg sysfs code to use default_groups
field which has been the preferred way since aa30f47cf6 ("kobject: Add
support for default attribute groups to kobj_type") so that we can soon
get rid of the obsolete default_attrs field.
Cc: Gabriel Somlo <somlo@cmu.edu>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: qemu-devel@nongnu.org
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20220105183133.2812848-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Explicitly remove the file entries from sysfs before dropping the final
reference for symmetry reasons and for consistency with the rest of the
driver.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211201132528.30025-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to always NUL-terminate file names retrieved from the firmware
to avoid accessing data beyond the entry slab buffer and exposing it
through sysfs in case the firmware data is corrupt.
Fixes: 75f3e8e47f ("firmware: introduce sysfs driver for QEMU's fw_cfg device")
Cc: stable@vger.kernel.org # 4.6
Cc: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211201132528.30025-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
An initialised kobject must be freed using kobject_put() to avoid
leaking associated resources (e.g. the object name).
Commit fe3c606843 ("firmware: Fix a reference count leak.") "fixed"
the leak in the first error path of the file registration helper but
left the second one unchanged. This "fix" would however result in a NULL
pointer dereference due to the release function also removing the never
added entry from the fw_cfg_entry_cache list. This has now been
addressed.
Fix the remaining kobject leak by restoring the common error path and
adding the missing kobject_put().
Fixes: 75f3e8e47f ("firmware: introduce sysfs driver for QEMU's fw_cfg device")
Cc: stable@vger.kernel.org # 4.6
Cc: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211201132528.30025-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit fe3c606843 ("firmware: Fix a reference count leak.") "fixed"
a kobject leak in the file registration helper by properly calling
kobject_put() for the entry in case registration of the object fails
(e.g. due to a name collision).
This would however result in a NULL pointer dereference when the
release function tries to remove the never added entry from the
fw_cfg_entry_cache list.
Fix this by moving the list-removal out of the release function.
Note that the offending commit was one of the benign looking umn.edu
fixes which was reviewed but not reverted. [1][2]
[1] https://lore.kernel.org/r/202105051005.49BFABCE@keescook
[2] https://lore.kernel.org/all/YIg7ZOZvS3a8LjSv@kroah.com
Fixes: fe3c606843 ("firmware: Fix a reference count leak.")
Cc: stable@vger.kernel.org # 5.8
Cc: Qiushi Wu <wu000273@umn.edu>
Cc: Kees Cook <keescook@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211201132528.30025-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fw_cfg_showrev() is called by an indirect call in kobj_attr_show(),
which violates clang's CFI checking because fw_cfg_showrev()'s second
parameter is 'struct attribute', whereas the ->show() member of 'struct
kobj_structure' expects the second parameter to be of type 'struct
kobj_attribute'.
$ cat /sys/firmware/qemu_fw_cfg/rev
3
$ dmesg | grep "CFI failure"
[ 26.016832] CFI failure (target: fw_cfg_showrev+0x0/0x8):
Fix this by converting fw_cfg_rev_attr to 'struct kobj_attribute' where
this would have been caught automatically by the incompatible pointer
types compiler warning. Update fw_cfg_showrev() accordingly.
Fixes: 75f3e8e47f ("firmware: introduce sysfs driver for QEMU's fw_cfg device")
Link: https://github.com/ClangBuiltLinux/linux/issues/1299
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210211194258.4137998-1-nathan@kernel.org
kobject_init_and_add() takes reference even when it fails.
If this function returns an error, kobject_put() must be called to
properly clean up the memory associated with the object.
Callback function fw_cfg_sysfs_release_entry() in kobject_put()
can handle the pointer "entry" properly.
Signed-off-by: Qiushi Wu <wu000273@umn.edu>
Link: https://lore.kernel.org/r/20200613190533.15712-1-wu000273@umn.edu
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
A couple of drivers produced build errors after the mod_devicetable.h
header was split out from the platform_device one, e.g.
drivers/media/platform/davinci/vpbe_osd.c:42:40: error: array type has incomplete element type 'struct platform_device_id'
drivers/media/platform/davinci/vpbe_venc.c:42:40: error: array type has incomplete element type 'struct platform_device_id'
This adds the inclusion where needed.
Fixes: ac3167257b ("headers: separate linux/mod_devicetable.h from linux/platform_device.h")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
If the "etc/vmcoreinfo" fw_cfg file is present and we are not running
the kdump kernel, write the addr/size of the vmcoreinfo ELF note.
The DMA operation is expected to run synchronously with today qemu,
but the specification states that it may become async, so we run
"control" field check in a loop for eventual changes.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add an optional <dma_off> kernel module (or command line) parameter
using the following syntax:
[qemu_fw_cfg.]ioport=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
or
[qemu_fw_cfg.]mmio=<size>@<base>[:<ctrl_off>:<data_off>[:<dma_off>]]
and initializes the register address using given or default offset.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Create a common header file for well-known values and structures to be
shared by the Linux kernel with qemu or other projects.
It is based from qemu/docs/specs/fw_cfg.txt which references
qemu/include/hw/nvram/fw_cfg_keys.h "for the most up-to-date and
authoritative list" & vmcoreinfo.txt. Those files don't have an
explicit license, but qemu/hw/nvram/fw_cfg.c is BSD-license, so
Michael S. Tsirkin suggested to use the same license.
The patch intentionally left out DMA & vmcoreinfo structures &
defines, which are added in the commits making usage of it.
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
fw_cfg_read_blob() may fail, but does not return error. This may lead
to surprising behaviours, like populating zero file entries (in
register_file() or during read). Return an error if ACPI locking
failed. Also, the following DMA read/write extension will add more
error paths that should be handled appropriately.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The function is not small and getting bigger.
Let the compiler decide instead. No profiling done, hopefully
unnecessary.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Use struct fw_cfg_files to read the directory size, fixing the sparse
warnings:
drivers/firmware/qemu_fw_cfg.c:485:17: warning: cast to restricted __be32
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Use a restricted type for reading FW_CFG_ID, fixing sparse warning:
drivers/firmware/qemu_fw_cfg.c:540:22: warning: cast to restricted __le32
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Modify fw_cfg_sysfs_entry to store entry values, instead of reusing
the restricted types.
Fixes warnings such as:
$ make C=1 CF=-D__CHECK_ENDIAN__ drivers/firmware/qemu_fw_cfg.o
drivers/firmware/qemu_fw_cfg.c:491:29: warning: incorrect type in assignment (different base types)
drivers/firmware/qemu_fw_cfg.c:491:29: expected restricted __be32 [usertype] size
drivers/firmware/qemu_fw_cfg.c:491:29: got unsigned int
drivers/firmware/qemu_fw_cfg.c:492:31: warning: incorrect type in assignment (different base types)
drivers/firmware/qemu_fw_cfg.c:492:31: expected restricted __be16 [usertype] select
drivers/firmware/qemu_fw_cfg.c:492:31: got int
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Dispatch to the appropriate iowrite() instead of casting restricted
type to u16.
- if fw_cfg_is_mmio:
before: iowrite16(cpu_to_be16(key))
after: iowrite16be(key)
- if !fw_cfg_is_mmio:
before: iowrite16(cpu_to_le16(key))
after: iowrite16(key)
which is equivalent on little-endian systems, where fw_cfg IO is supported.
Fixes:
$ make C=1 CF=-D__CHECK_ENDIAN__ drivers/firmware/qemu_fw_cfg.o
drivers/firmware/qemu_fw_cfg.c:55:33: warning: restricted __be16 degrades to integer
drivers/firmware/qemu_fw_cfg.c:55:52: warning: restricted __le16 degrades to integer
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fix ptr_ret.cocci warnings:
drivers/firmware/efi/efi.c:610:8-14: WARNING: PTR_ERR_OR_ZERO can be used
Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR
Generated by: scripts/coccinelle/api/ptr_ret.cocci
Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Gabriel Somlo <somlo@cmu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
On driver remove(), all objects created during probe() should be
removed, but sysfs qemu_fw_cfg/rev file was left. Also reorder
functions to match probe() error cleanup code.
Cc: stable@vger.kernel.org
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Here's the "big" driver core update for 4.7-rc1.
Mostly just debugfs changes, the long-known and messy races with removing
debugfs files should be fixed thanks to the great work of Nicolai Stange. We
also have some isa updates in here (the x86 maintainers told me to take it
through this tree), a new warning when we run out of dynamic char major
numbers, and a few other assorted changes, details in the shortlog.
All have been in linux-next for some time with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here's the "big" driver core update for 4.7-rc1.
Mostly just debugfs changes, the long-known and messy races with
removing debugfs files should be fixed thanks to the great work of
Nicolai Stange. We also have some isa updates in here (the x86
maintainers told me to take it through this tree), a new warning when
we run out of dynamic char major numbers, and a few other assorted
changes, details in the shortlog.
All have been in linux-next for some time with no reported issues"
* tag 'driver-core-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (32 commits)
Revert "base: dd: don't remove driver_data in -EPROBE_DEFER case"
gpio: ws16c48: Utilize the ISA bus driver
gpio: 104-idio-16: Utilize the ISA bus driver
gpio: 104-idi-48: Utilize the ISA bus driver
gpio: 104-dio-48e: Utilize the ISA bus driver
watchdog: ebc-c384_wdt: Utilize the ISA bus driver
iio: stx104: Utilize the module_isa_driver and max_num_isa_dev macros
iio: stx104: Add X86 dependency to STX104 Kconfig option
Documentation: Add ISA bus driver documentation
isa: Implement the max_num_isa_dev macro
isa: Implement the module_isa_driver macro
pnp: pnpbios: Add explicit X86_32 dependency to PNPBIOS
isa: Decouple X86_32 dependency from the ISA Kconfig option
driver-core: use 'dev' argument in dev_dbg_ratelimited stub
base: dd: don't remove driver_data in -EPROBE_DEFER case
kernfs: Move faulting copy_user operations outside of the mutex
devcoredump: add scatterlist support
debugfs: unproxify files created through debugfs_create_u32_array()
debugfs: unproxify files created through debugfs_create_blob()
debugfs: unproxify files created through debugfs_create_bool()
...
It acpi_acquire_global_lock() return AE_NOT_CONFIGURED then "glk" isn't
initialized, which, if you got very unlucky, could cause a bug.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Allowing for the future possibility of implementing AML-based
(i.e., firmware-triggered) access to the QEMU fw_cfg device,
acquire the global ACPI lock when accessing the device on behalf
of the guest-side sysfs driver, to prevent any potential race
conditions.
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If platform_driver_register fails, we should
cleanup fw_cfg_top_ko before exiting.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Gabriel Somlo <somlo@cmu.edu>
Refrain from defining default fw_cfg register offsets on
unsupported architectures -- throw an error instead. If
QEMU were to add fw_cfg support on additional architectures,
we should add them to the FW_CFG_SYSFS depends statement in
drivers/firmware/Kconfig, and provide default values for
register offsets in drivers/firmware/qemu_fw_cfg.c at that
time.
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Each fw_cfg entry of type "file" has an associated 56-char,
nul-terminated ASCII string which represents its name. While
the fw_cfg device doesn't itself impose any specific naming
convention, QEMU developers have traditionally used path name
semantics (i.e. "etc/acpi/rsdp") to descriptively name the
various fw_cfg "blobs" passed into the guest.
This patch attempts, on a best effort basis, to create a
directory hierarchy representing the content of fw_cfg file
names, under /sys/firmware/qemu_fw_cfg/by_name.
Upon successful creation of all directories representing the
"dirname" portion of a fw_cfg file, a symlink will be created
to represent the "basename", pointing at the appropriate
/sys/firmware/qemu_fw_cfg/by_key entry. If a file name is not
suitable for this procedure (e.g., if its basename or dirname
components collide with an already existing dirname component
or basename, respectively) the corresponding fw_cfg blob is
skipped and will remain available in sysfs only by its selector
key value.
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make fw_cfg entries of type "file" available via sysfs. Entries
are listed under /sys/firmware/qemu_fw_cfg/by_key, in folders
named after each entry's selector key. Filename, selector value,
and size read-only attributes are included for each entry. Also,
a "raw" attribute allows retrieval of the full binary content of
each entry.
The fw_cfg device can be instantiated automatically from ACPI or
the Device Tree, or manually by using a kernel module (or command
line) parameter, with a syntax outlined in the documentation file.
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
