max_num_isa_dev is a macro to determine the maximum possible number of
ISA devices which may be registered in the I/O port address space given
the address extent of the ISA devices.
The highest base address possible for an ISA device is 0x3FF; this
results in 1024 possible base addresses. Dividing the number of possible
base addresses by the address extent taken by each device results in the
maximum number of devices on a system.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The module_isa_driver macro is a helper macro for ISA drivers which do
not do anything special in module init/exit. This eliminates a lot of
boilerplate code. Each module may only use this macro once, and calling
it replaces module_init and module_exit.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pnp: pnpbios: Add explicit X86_32 dependency to PNPBIOS
The PNPBIOS driver requires preprocessor defines (located in
include/asm/segment.h) only declared if the architecture is set to
X86_32. If the architecture is set to X86_64, the PNPBIOS driver will
not build properly. The X86 dependecy for the PNPBIOS configuration
option is changed to an explicit X86_32 dependency in order to prevent
an attempt to build for an unsupported architecture.
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
isa: Decouple X86_32 dependency from the ISA Kconfig option
The introduction of the ISA_BUS option blocks the compilation of ISA
drivers on non-x86 platforms. The ISA_BUS configuration option should
not be necessary if the X86_32 dependency can be decoupled from the ISA
configuration option. This patch both removes the ISA_BUS configuration
option entirely and removes the X86_32 dependency from the ISA
configuration option.
Arnd Bergmann [Thu, 24 Mar 2016 21:19:40 +0000 (22:19 +0100)]
driver-core: use 'dev' argument in dev_dbg_ratelimited stub
dev_dbg_ratelimited() is a macro that ignores its first argument when DEBUG is
not set, which can lead to unused variable warnings:
ethernet/mellanox/mlxsw/pci.c: In function 'mlxsw_pci_cqe_sdq_handle':
ethernet/mellanox/mlxsw/pci.c:646:18: warning: unused variable 'pdev' [-Wunused-variable]
ethernet/mellanox/mlxsw/pci.c: In function 'mlxsw_pci_cqe_rdq_handle':
ethernet/mellanox/mlxsw/pci.c:671:18: warning: unused variable 'pdev' [-Wunused-variable]
The macro already ensures that all its other arguments are silently
ignored by the compiler without triggering a warning, through the
use of the no_printk() macro, but the dev argument is not passed into
that.
This changes the definition to use the same trick as no_printk() with
an if(0) that leads the compiler to not evaluate the side-effects but
still see that 'dev' might not be unused.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Andrew Lunn <andrew@lunn.ch> Fixes: 6f586e663e3b ("driver-core: Shut up dev_dbg_reatelimited() without DEBUG") Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Yi Zhang [Tue, 8 Mar 2016 15:15:22 +0000 (23:15 +0800)]
base: dd: don't remove driver_data in -EPROBE_DEFER case
the driver_data may be used for sanity check, it fails the
probe() if driver_data is NULL after it is re-triggered.
for example, soc_probe() in sound/soc/soc-core.c
Signed-off-by: Yi Zhang <yizhang_hust@163.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Chris Wilson [Thu, 31 Mar 2016 10:45:06 +0000 (11:45 +0100)]
kernfs: Move faulting copy_user operations outside of the mutex
A fault in a user provided buffer may lead anywhere, and lockdep warns
that we have a potential deadlock between the mm->mmap_sem and the
kernfs file mutex:
[ 82.811702] ======================================================
[ 82.811705] [ INFO: possible circular locking dependency detected ]
[ 82.811709] 4.5.0-rc4-gfxbench+ #1 Not tainted
[ 82.811711] -------------------------------------------------------
[ 82.811714] kms_setmode/5859 is trying to acquire lock:
[ 82.811717] (&dev->struct_mutex){+.+.+.}, at: [<ffffffff8150d9c1>] drm_gem_mmap+0x1a1/0x270
[ 82.811731]
but task is already holding lock:
[ 82.811734] (&mm->mmap_sem){++++++}, at: [<ffffffff8117b364>] vm_mmap_pgoff+0x44/0xa0
[ 82.811745]
which lock already depends on the new lock.
Highly unlikely though this scenario is, we can avoid the issue entirely
by moving the copy operation from out under the kernfs_get_active()
tracking by assigning the preallocated buffer its own mutex. The
temporary buffer allocation doesn't require mutex locking as it is
entirely local.
The locked section was extended by the addition of the preallocated buf
to speed up md user operations in
Merge tag 'dm-4.6-fix-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fix from Mike Snitzer:
"Fix for earlier 4.6-rc4 stable@ commit that introduced improper use of
write lock in cmd_read_lock() -- due to cut-n-paste gone awry (and
sparse didn't catch it)"
* tag 'dm-4.6-fix-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm cache metadata: fix cmd_read_lock() acquiring write lock
Commit 9567366fefdd ("dm cache metadata: fix READ_LOCK macros and
cleanup WRITE_LOCK macros") uses down_write() instead of down_read() in
cmd_read_lock(), yet up_read() is used to release the lock in
READ_UNLOCK(). Fix it.
Fixes: 9567366fefdd ("dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros") Cc: stable@vger.kernel.org Signed-off-by: Ahmed Samy <f.fallen45@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Merge tag 'char-misc-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc fixes from Greg KH:
"Here are some small char/misc driver fixes for 4.6-rc4. Full details
are in the shortlog, nothing major here.
These have all been in linux-next for a while with no reported issues"
* tag 'char-misc-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
lkdtm: do not leak free page on kmalloc failure
lkdtm: fix memory leak of base
lkdtm: fix memory leak of val
extcon: palmas: Drop stray IRQF_EARLY_RESUME flag
Merge tag 'driver-core-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull misc fixes from Greg KH:
"Here are three small fixes for 4.6-rc4.
Two fix up some lz4 issues with big endian systems, and the remaining
one resolves a minor debugfs issue that was reported.
All have been in linux-next with no reported issues"
* tag 'driver-core-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
lib: lz4: cleanup unaligned access efficiency detection
lib: lz4: fixed zram with lz4 on big endian machines
debugfs: Make automount point inodes permanently empty
Merge tag 'usb-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB driver fixes from Greg KH:
"Here are some small USB fixes for 4.6-rc4.
Mostly xhci fixes for reported issues, a UAS bug that has hit a number
of people, including stable tree users, and a few other minor things.
All have been in linux-next for a while with no reported issues"
* tag 'usb-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: hcd: out of bounds access in for_each_companion
USB: uas: Add a new NO_REPORT_LUNS quirk
USB: uas: Limit qdepth at the scsi-host level
doc: usb: Fix typo in gadget_multi documentation
usb: host: xhci-plat: Make enum xhci_plat_type start at a non zero value
xhci: fix 10 second timeout on removal of PCI hotpluggable xhci controllers
usb: xhci: fix wild pointers in xhci_mem_cleanup
usb: host: xhci-plat: fix cannot work if R-Car Gen2/3 run on above 4GB phys
usb: host: xhci: add a new quirk XHCI_NO_64BIT_SUPPORT
xhci: resume USB 3 roothub first
usb: xhci: applying XHCI_PME_STUCK_QUIRK to Intel BXT B0 host
cdc-acm: fix crash if flushed with nothing buffered
Merge tag 'dmaengine-fix-4.6-rc4' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fixes from Vinod Koul:
"This time we have some odd fixes in hsu, edma, omap and xilinx.
Usual fixes and nothing special"
* tag 'dmaengine-fix-4.6-rc4' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: dw: fix master selection
dmaengine: edma: special case slot limit workaround
dmaengine: edma: Remove dynamic TPTC power management feature
dmaengine: vdma: don't crash when bad channel is requested
dmaengine: omap-dma: Do not suppress interrupts for memcpy
dmaengine: omap-dma: Fix polled channel completion detection and handling
dmaengine: hsu: correct use of channel status register
dmaengine: hsu: correct residue calculation of active descriptor
dmaengine: hsu: set HSU_CH_MTSR to memory width
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A few fixes for the current series. This contains:
- Two fixes for NVMe:
One fixes a reset race that can be triggered by repeated
insert/removal of the module.
The other fixes an issue on some platforms, where we get probe
timeouts since legacy interrupts isn't working. This used not to
be a problem since we had the worker thread poll for completions,
but since that was killed off, it means those poor souls can't
successfully probe their NVMe device. Use a proper IRQ check and
probe (msi-x -> msi ->legacy), like most other drivers to work
around this. Both from Keith.
- A loop corruption issue with offset in iters, from Ming Lei.
- A fix for not having the partition stat per cpu ref count
initialized before sending out the KOBJ_ADD, which could cause user
space to access the counter prior to initialization. Also from
Ming Lei.
- A fix for using the wrong congestion state, from Kaixu Xia"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: loop: fix filesystem corruption in case of aio/dio
NVMe: Always use MSI/MSI-x interrupts
NVMe: Fix reset/remove race
writeback: fix the wrong congested state variable definition
block: partition: initialize percpuref before sending out KOBJ_ADD
Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Ross Zwisler:
"Two fixes:
- Fix memcpy_from_pmem() to fallback to memcpy() for architectures
where CONFIG_ARCH_HAS_PMEM_API=n.
- Add a comment explaining why we write data twice when clearing
poison in pmem_do_bvec().
This has passed a boot test on an X86_32 config, which was the
architecture where issue #1 above was first noticed"
Dan Williams adds:
"We're giving this multi-maintainer setup a shot, so expect libnvdimm
pull requests from either Ross or I going forward"
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm, pmem: clarify the write+clear_poison+write flow
pmem: fix BUG() error in pmem.h:48 on X86_32
Merge tag 'mmc-v4.6-rc3' of git://git.linaro.org/people/ulf.hansson/mmc
Pull MMC fixes from Ulf Hansson:
"Here are a couple of mmc fixes intended for v4.6 rc4.
Regarding the fix for the regression about mmcblk device indexes. The
approach taken to solve the problem seems to be good enough. There
were some discussions around the solution, but it seems like people
were happy about it in the end.
MMC core:
- Restore similar old behaviour when assigning mmcblk device indexes
MMC host:
- tegra: Disable UHS-I modes for Tegra124 to fix regression"
* tag 'mmc-v4.6-rc3' of git://git.linaro.org/people/ulf.hansson/mmc:
mmc: tegra: Disable UHS-I modes for Tegra124
mmc: block: Use the mmc host device index as the mmcblk device index
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"This contains fixes for exynos, amdgpu, radeon, i915 and qxl.
It also contains some fixes to the core drm edid parser.
qxl:
- fix for a cursor hotspot issue
radeon:
- some MST fixes that I've been running locally and make my monitor a
bit happier
exynos:
- fix some regressions and build fixes
amdgpu:
- a couple of small fixes
i915:
- two DP MST fixes and a couple of other regression fixes
Nothing too out of the ordinary or surprising at this point"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/exynos: Use VIDEO_SAMSUNG_S5P_G2D=n as G2D Kconfig dependency
drm/exynos: fix a warning message
drm/exynos: mic: fix an error code
drm/exynos: fimd: fix broken dp_clock control
drm/exynos: build fbdev code conditionally
drm/exynos: fix adjusted_mode pointer in exynos_plane_mode_set
drm/exynos: fix error handling in exynos_drm_subdrv_open
drm/amd/amdgpu: fix irq domain remove for tonga ih
drm/i915: fix deadlock on lid open
drm/radeon: use helper for mst connector dpms.
drm/radeon/mst: port some MST setup code from DAL.
drm/amdgpu: add invisible pin size statistic
drm/edid: Fix DMT 1024x768@43Hz (interlaced) timings
drm/i915: Exit cherryview_irq_handler() after one pass
drm/i915: Call intel_dp_mst_resume() before resuming displays
drm/i915: Fix race condition in intel_dp_destroy_mst_connector()
drm/edid: Fix parsing of EDID 1.4 Established Timings III descriptor
drm/edid: Fix EDID Established Timings I and II
drm/qxl: fix cursor position with non-zero hotspot
Merge branch 'parisc-4.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc ftrace fixes from Helge Deller:
"This is (most likely) the last pull request for v4.6 for the parisc
architecture.
It fixes the FTRACE feature for parisc, which is horribly broken since
quite some time and doesn't even compile. This patch just fixes the
bare minimum (it actually removes more lines than it adds), so that
the function tracer works again on 32- and 64bit kernels.
I've queued up additional patches on top of this patch which e.g. add
the syscall tracer, but those have to wait for the merge window for
v4.7."
* 'parisc-4.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix ftrace function tracer
Dan Williams [Fri, 15 Apr 2016 02:40:47 +0000 (19:40 -0700)]
libnvdimm, pmem: clarify the write+clear_poison+write flow
The ACPI specification does not specify the state of data after a clear
poison operation. Potential future libnvdimm bus implementations for
other architectures also might not specify or disagree on the state of
data after clear poison. Clarify why we write twice.
Reported-by: Jeff Moyer <jmoyer@redhat.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Add scatterlist support (dev_coredumpsg) to allow drivers to avoid
vmalloc() like dev_coredumpm(), while also avoiding the module
reference that the latter function requires.
This internally uses dev_coredumpm() with function inside the
devcoredump module, requiring removing the const
(which touches the driver using it.)
Ming Lei [Fri, 15 Apr 2016 10:51:28 +0000 (18:51 +0800)]
block: loop: fix filesystem corruption in case of aio/dio
Starting from commit e36f620428(block: split bios to max possible length),
block core starts to split bio in the middle of bvec.
Unfortunately loop dio/aio doesn't consider this situation, and
always treat 'iter.iov_offset' as zero. Then filesystem corruption
is observed.
This patch figures out the offset of the base bvevc via
'bio->bi_iter.bi_bvec_done' and fixes the issue by passing the offset
to iov iterator.
Fixes: e36f6204288088f (block: split bios to max possible length) Cc: Keith Busch <keith.busch@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@vger.kernel.org (4.5) Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"Misc fixes: a binutils fix, an lguest fix, an mcelog fix and a missing
documentation fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Avoid using object after free in genpool
lguest, x86/entry/32: Fix handling of guest syscalls using interrupt gates
x86/build: Build compressed x86 kernels as PIE
x86/mm/pkeys: Add missing Documentation
Merge branch 'mm-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull mm gup cleanup from Ingo Molnar:
"This removes the ugly get-user-pages API hack, now that all upstream
code has been migrated to it"
("ugly" is putting it mildly. But it worked.. - Linus)
* 'mm-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
mm/gup: Remove the macro overload API migration helpers from the get_user*() APIs
Merge tag 'dm-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- fix a 4.6-rc1 bio-based DM 'struct dm_target_io' leak in an error
path
- stable@ fix for DM cache metadata's READ_LOCK macros that were
incorrectly returning error if the block manager was in read-only
mode; also cleanup multi-statement macros to use do {} while(0)
* tag 'dm-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros
dm: fix dm_target_io leak if clone_bio() returns an error
Merge tag 'sound-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"We've had a very calm development cycle, so far. Here are the few
fixes for HD-audio and USB-audio, all of which are small and easy"
* tag 'sound-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Fix inconsistent monitor_present state until repoll
ALSA: hda - Fix regression of monitor_present flag in eld proc file
ALSA: usb-audio: Skip volume controls triggers hangup on Dell USB Dock
ALSA: hda/realtek - Enable the ALC292 dock fixup on the Thinkpad T460s
ALSA: sscape: Use correct format identifier for size_t
ALSA: usb-audio: Add a quirk for Plantronics BT300
ALSA: usb-audio: Add a sample rate quirk for Phoenix Audio TMX320
ALSA: hda - Bind with i915 only when Intel graphics is present
Merge branch 'mailbox-devel' of git://git.linaro.org/landing-teams/working/fujitsu/integration
Pull mailbox fixes from Jussi Brar:
"Misc fixes:
mailbox-test driver:
- prevent memory leak and another cosmetic change
mailbox:
- change the returned error code
Xgene driver:
- return -ENOMEM instead of PTR_ERR for failed devm_kzalloc"
* 'mailbox-devel' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
mailbox: Stop using ENOSYS for anything other than unimplemented syscalls
mailbox: mailbox-test: Prevent memory leak
mailbox: mailbox-test: Use more consistent format for calling copy_from_user()
mailbox: xgene-slimpro: Fix wrong test for devm_kzalloc
Merge tag 'for-linus-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs/fscrypto fixes from Jaegeuk Kim:
"In addition to f2fs/fscrypto fixes, I've added one patch which
prevents RCU mode lookup in d_revalidate, as Al mentioned.
These patches fix f2fs and fscrypto based on -rc3 bug fixes in ext4
crypto, which have not yet been fully propagated as follows.
- use of dget_parent and file_dentry to avoid crashes
- disallow RCU-mode lookup in d_invalidate
- disallow -ENOMEM in the core data encryption path"
* tag 'for-linus-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
ext4/fscrypto: avoid RCU lookup in d_revalidate
fscrypto: don't let data integrity writebacks fail with ENOMEM
f2fs: use dget_parent and file_dentry in f2fs_file_open
fscrypto: use dget_parent() in fscrypt_d_revalidate()
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
"This fixes an NFS regression caused by the skcipher/hash conversion in
sunrpc. It also fixes a build problem in certain configurations with
bcm63xx"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
hwrng: bcm63xx - fix device tree compilation
sunrpc: Fix skcipher/shash conversion
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull keys bugfixes from James Morris:
"Two bugfixes for Keys related code"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
ASN.1: fix open failure check on headername
assoc_array: don't call compare_object() on a node
Mike Snitzer [Tue, 12 Apr 2016 16:14:46 +0000 (12:14 -0400)]
dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros
The READ_LOCK macro was incorrectly returning -EINVAL if
dm_bm_is_read_only() was true -- it will always be true once the cache
metadata transitions to read-only by dm_cache_metadata_set_read_only().
Wrap READ_LOCK and WRITE_LOCK multi-statement macros in do {} while(0).
Also, all accesses of the 'cmd' argument passed to these related macros
are now encapsulated in parenthesis.
A follow-up patch can be developed to eliminate the use of macros in
favor of pure C code. Avoiding that now given that this needs to apply
to stable@.
Reported-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Fixes: d14fcf3dd79 ("dm cache: make sure every metadata function checks fail_io") Cc: stable@vger.kernel.org
Keith Busch [Fri, 8 Apr 2016 22:09:10 +0000 (16:09 -0600)]
NVMe: Always use MSI/MSI-x interrupts
Multiple users have reported device initialization failure due the driver
not receiving legacy PCI interrupts. This is not unique to any particular
controller, but has been observed on multiple platforms.
There have been no issues reported or observed when with message signaled
interrupts, so this patch attempts to use MSI-x during initialization,
falling back to MSI. If that fails, legacy would become the default.
The setup_io_queues error handling had to change as a result: the admin
queue's msix_entry used to be initialized to the legacy IRQ. The case
where nr_io_queues is 0 would fail request_irq when setting up the admin
queue's interrupt since re-enabling MSI-x fails with 0 vectors, leaving
the admin queue's msix_entry invalid. Instead, return success immediately.
Reported-by: Tim Muhlemmer <muhlemmer@gmail.com> Reported-by: Jon Derrick <jonathan.derrick@intel.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
/proc/iomem: only expose physical resource addresses to privileged users
In commit c4004b02f8e5b ("x86: remove the kernel code/data/bss resources
from /proc/iomem") I was hoping to remove the phyiscal kernel address
data from /proc/iomem entirely, but that had to be reverted because some
system programs actually use it.
This limits all the detailed resource information to properly
credentialed users instead.
pci-sysfs: use proper file capability helper function
The PCI config access checked the file capabilities correctly, but used
the itnernal security capability check rather than the helper function
that is actually meant for that.
The security_capable() has unusual return values and is not meant to be
used elsewhere (the only other use is in the capability checking
functions that we actually intend people to use, and this odd PCI usage
really stood out when looking around the capability code.
Make file credentials available to the seqfile interfaces
A lot of seqfile users seem to be using things like %pK that uses the
credentials of the current process, but that is actually completely
wrong for filesystem interfaces.
The unix semantics for permission checking files is to check permissions
at _open_ time, not at read or write time, and that is not just a small
detail: passing off stdin/stdout/stderr to a suid application and making
the actual IO happen in privileged context is a classic exploit
technique.
So if we want to be able to look at permissions at read time, we need to
use the file open credentials, not the current ones. Normal file
accesses can just use "f_cred" (or any of the helper functions that do
that, like file_ns_capable()), but the seqfile interfaces do not have
any such options.
It turns out that seq_file _does_ save away the user_ns information of
the file, though. Since user_ns is just part of the full credential
information, replace that special case with saving off the cred pointer
instead, and suddenly seq_file has all the permission information it
needs.
Sadly, my hope that nobody would actually use the special kernel entries
in /proc/iomem were dashed by kexec. Which reads /proc/iomem explicitly
to find the kernel base address. Nasty.
Anyway, that means we can't do the sane and simple thing and just remove
the entries, and we'll instead have to mask them out based on permissions.
Reported-by: Zhengyu Zhang <zhezhang@redhat.com> Reported-by: Dave Young <dyoung@redhat.com> Reported-by: Freeman Zhang <freeman.zhang1992@gmail.com> Reported-by: Emrah Demir <ed@abdsec.com> Reported-by: Baoquan He <bhe@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After 'commit fc0c2028135c ("x86, pmem: use memcpy_mcsafe()
for memcpy_from_pmem()")', probing a PMEM device hits the BUG()
error below on X86_32 kernel.
kernel BUG at include/linux/pmem.h:48!
memcpy_from_pmem() calls arch_memcpy_from_pmem(), which is
unimplemented since CONFIG_ARCH_HAS_PMEM_API is undefined on
X86_32.
Fix the BUG() error by adding default_memcpy_from_pmem().
Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
The RB-tree regmap cache needs to allocate new space on first writes.
However, allocations in an atomic context (e.g. when a spinlock is held)
are not allowed. The function regmap_write calls map->lock, which
acquires a spinlock in the fast_io case. Since the pwm-fsl-ftm driver
uses MMIO, the regmap bus of type regmap_mmio is being used which has
fast_io set to true.
The MMIO space of the pwm-fsl-ftm driver is reasonable condense, hence
using the much faster flat regmap cache is anyway the better choice.
Signed-off-by: Stefan Agner <stefan@agner.ch> Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Jon Hunter [Wed, 13 Apr 2016 14:35:56 +0000 (15:35 +0100)]
mmc: tegra: Disable UHS-I modes for Tegra124
Tegra124 has been randomly hanging during system suspend when entering
the Tegra LP1 low power state. The hang is caused by the Tegra SDHCI
driver and linked to the UHS-I tuning sequence. Disabling the UHS-I
modes for Tegra124 prevents any hangs from occurring when entering
system suspend.
Unfortunately, the tuning sequence described in the public Tegra
documentation is incomplete and on inspection of the current tuning
sequence that has been implemented is also incomplete and may cause
problems. In the short-term it is safer to disable UHS-I modes for now
and fix later because it would be too large of a change to simply patch
now. Therefore, disable UHS-I modes for Tegra124.
mmc: block: Use the mmc host device index as the mmcblk device index
Commit 520bd7a8b415 ("mmc: core: Optimize boot time by detecting cards
simultaneously") causes regressions for some platforms.
These platforms relies on fixed mmcblk device indexes, instead of
deploying the defacto standard with UUID/PARTUUID. In other words their
rootfs needs to be available at hardcoded paths, like /dev/mmcblk0p2.
Such guarantees have never been made by the kernel, but clearly the above
commit changes the behaviour. More precisely, because of that the order
changes of how cards becomes detected, so do their corresponding mmcblk
device indexes.
As the above commit significantly improves boot time for some platforms
(magnitude of seconds), let's avoid reverting this change but instead
restore the behaviour of how mmcblk device indexes becomes picked.
By using the same index for the mmcblk device as for the corresponding mmc
host device, the probe order of mmc host devices decides the index we get
for the mmcblk device.
For those platforms that suffers from a regression, one could expect that
this updated behaviour should be sufficient to meet their expectations of
"fixed" mmcblk device indexes.
Another side effect from this change, is that the same index is used for
the mmc host device, the mmcblk device and the mmc block queue. That
should clarify their relationship.
Reported-by: Peter Hurley <peter@hurleysoftware.com> Reported-by: Laszlo Fiat <laszlo.fiat@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Fixes: 520bd7a8b415 ("mmc: core: Optimize boot time by detecting cards
simultaneously") Cc: <stable@vger.kernel.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Dave Airlie [Thu, 14 Apr 2016 03:05:56 +0000 (13:05 +1000)]
Merge branch 'drm-fixes-4.6' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
some misc radeon fixes.
* 'drm-fixes-4.6' of git://people.freedesktop.org/~agd5f/linux:
drm/amd/amdgpu: fix irq domain remove for tonga ih
drm/radeon: use helper for mst connector dpms.
drm/radeon/mst: port some MST setup code from DAL.
drm/amdgpu: add invisible pin size statistic
Merge tag 'sh-fixes-4.6-rc1' of git://git.libc.org/linux-sh
Pull arch/sh fixes from Rich Felker:
"Fixes for two arch/sh build regressions that appeared in 4.6-rc1, one
introduced by me, and one caused by changes elsewhere"
* tag 'sh-fixes-4.6-rc1' of git://git.libc.org/linux-sh:
sh: fix function signature of cpu_coregroup_mask to match pointer type
sh: fix smp-shx3 build regression from removal of arch localtimer
usb: hcd: out of bounds access in for_each_companion
On BXT platform Host Controller and Device Controller figure as
same PCI device but with different device function. HCD should
not pass data to Device Controller but only to Host Controllers.
Checking if companion device is Host Controller, otherwise skip.
Cc: <stable@vger.kernel.org> Signed-off-by: Robert Dobrowolski <robert.dobrowolski@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hans de Goede [Tue, 12 Apr 2016 10:27:09 +0000 (12:27 +0200)]
USB: uas: Add a new NO_REPORT_LUNS quirk
Add a new NO_REPORT_LUNS quirk and set it for Seagate drives with
an usb-id of: 0bc2:331a, as these will fail to respond to a
REPORT_LUNS command.
Cc: stable@vger.kernel.org Reported-and-tested-by: David Webb <djw@noc.ac.uk> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hans de Goede [Tue, 12 Apr 2016 10:27:08 +0000 (12:27 +0200)]
USB: uas: Limit qdepth at the scsi-host level
Commit 64d513ac31bd ("scsi: use host wide tags by default") causes
the SCSI core to queue more commands then we can handle on devices with
multiple LUNs, limit the queue depth at the scsi-host level instead of
per slave to fix this.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1315013 Cc: stable@vger.kernel.org # 4.4.x and 4.5.x Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Griffin [Wed, 13 Apr 2016 16:58:44 +0000 (19:58 +0300)]
usb: host: xhci-plat: Make enum xhci_plat_type start at a non zero value
Otherwise generic-xhci and xhci-platform which have no data get wrongly
detected as XHCI_PLAT_TYPE_MARVELL_ARMADA by xhci_plat_type_is().
This fixes a regression in v4.5 for STiH407 family SoC's which use the
synopsis dwc3 IP, whereby the disable_clk error path gets taken due to
wrongly being detected as XHCI_PLAT_TYPE_MARVELL_ARMADA and the hcd never
gets added.
I suspect this will also fix other dwc3 DT platforms such as Exynos,
although I've only tested on STih410 SoC.
xhci: fix 10 second timeout on removal of PCI hotpluggable xhci controllers
PCI hotpluggable xhci controllers such as some Alpine Ridge solutions will
remove the xhci controller from the PCI bus when the last USB device is
disconnected.
Add a flag to indicate that the host is being removed to avoid queueing
configure_endpoint commands for the dropped endpoints.
For PCI hotplugged controllers this will prevent 5 second command timeouts
For static xhci controllers the configure_endpoint command is not needed
in the removal case as everything will be returned, freed, and the
controller is reset.
For now the flag is only set for PCI connected host controllers.
usb: host: xhci: add a new quirk XHCI_NO_64BIT_SUPPORT
On some xHCI controllers (e.g. R-Car SoCs), the AC64 bit (bit 0) of
HCCPARAMS1 is set to 1. However, the xHCs don't support 64-bit
address memory pointers actually. So, in this case, this driver should
call dma_set_coherent_mask(dev, DMA_BIT_MASK(32)) in xhci_gen_setup().
Otherwise, the xHCI controller will be died after a usb device is
connected if it runs on above 4GB physical memory environment.
So, this patch adds a new quirk XHCI_NO_64BIT_SUPPORT to resolve
such an issue.
Give USB3 devices a better chance to enumerate at USB 3 speeds if
they are connected to a suspended host.
Solves an issue with NEC uPD720200 host hanging when partially
enumerating a USB3 device as USB2 after host controller runtime resume.
These identifiers are bogus. The interested architectures should define
HAVE_EFFICIENT_UNALIGNED_ACCESS whenever relevant to do so. If this
isn't true for some arch, it should be fixed in the arch definition.
lib: lz4: fixed zram with lz4 on big endian machines
Based on Sergey's test patch [1], this fixes zram with lz4 compression
on big endian cpus.
Note that the 64-bit preprocessor test is not a cleanup, it's part of
the fix, since those identifiers are bogus (for example, __ppc64__
isn't defined anywhere else in the kernel, which means we'd fall into
the 32-bit definitions on ppc64).
Andy Shevchenko [Fri, 8 Apr 2016 13:22:17 +0000 (16:22 +0300)]
dmaengine: dw: fix master selection
The commit 895005202987 ("dmaengine: dw: apply both HS interfaces and remove
slave_id usage") cleaned up the code to avoid usage of depricated slave_id
member of generic slave configuration.
Meanwhile it broke the master selection by removing important call to
dwc_set_masters() in ->device_alloc_chan_resources() which copied masters from
custom slave configuration to the internal channel structure.
Everything works until now since there is no customized connection of
DesignWare DMA IP to the bus, i.e. one bus and one or more masters are in use.
The configurations where 2 masters are connected to the different masters are
not working anymore. We are expecting one user of such configuration and need
to select masters properly. Besides that it is obviously a performance
regression since only one master is in use in multi-master configuration.
Select masters in accordance with what user asked for. Keep this patch in a form
more suitable for back porting.
We are safe to take necessary data in ->device_alloc_chan_resources() because
we don't support generic slave configuration embedded into custom one, and thus
the only way to provide such is to use the parameter to a filter function which
is called exactly before channel resource allocation.
While here, replase BUG_ON to less noisy dev_warn() and prevent channel
allocation in case of error.
Fixes: 895005202987 ("dmaengine: dw: apply both HS interfaces and remove slave_id usage") Cc: stable@vger.kernel.org Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68knommu/coldfire fix from Greg Ungerer:
"Only a single change that removes a local arch specific gpio bus sysfs
device that now clashes with the generic gpio bus sysfs device
interface"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68k/gpio: remove arch specific sysfs bus device
Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"A batch of fixes for -rc4, for various platforms.
Nothing really substantial and worth pointing out in particular; small
fixes for various bugs, see shortlog for details"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: sa1100: remove references to the defunct handhelds.org
bus: uniphier-system-bus: fix condition of overlap check
ARM: uniphier: drop weird sizeof()
ARM: dts: am335x-baltos-ir5221: fix cpsw_emac0 link type
ARM: OMAP: Correct interrupt type for ARM TWD
ARM: DRA722: Add ID detect for Silicon Rev 2.0
ARM: dts: am43xx: fix edma memcpy channel allocation
ARM: dts: AM43x-epos: Fix clk parent for synctimer
ARM: OMAP2: Fix up interconnect barrier initialization for DRA7
documentation: Fix pinctrl documentation for Meson8 / Meson8b
ARM: dts: amlogic: Split pinctrl device for Meson8 / Meson8b
ARM: mvebu: Correct unit address for linksys
bus: mvebu-mbus: use %pa to print phys_addr_t
arm64: dts: vulcan: Update PCI ranges
ARM: u8500_defconfig: turn on the Synaptics RMI4 driver
ARM: pxa: fix the number of DMA requestor lines
ARM: OMAP2+: hwmod: Fix updating of sysconfig register
ARM: OMAP2+: Use srst_udelay for USB on dm814x
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Radim Krčmář:
"ARM fixes:
- Wrong indentation in the PMU code from the merge window
- A long-time bug occuring with running ntpd on the host, candidate
for stable
- Properly handle (and warn about) the unsupported configuration of
running on systems with less than 40 bits of PA space
- More fixes to the PM and hotplug notifier stuff from the merge
window
x86:
- leak of guest xcr0 (typically shows up as SIGILL)
- new maintainer (who is sending the pull request too)
- fix for merge window regression
- fix for guest CPUID"
Paolo Bonzini points out:
"For the record, this tag is signed by me because I prepared the pull
request. Further pull requests for 4.6 will be signed and sent out by
Radim directly"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: mask CPUID(0xD,0x1).EAX against host value
kvm: x86: do not leak guest xcr0 into host interrupt handlers
KVM: MMU: fix permission_fault()
KVM: new maintainer on the block
arm64: KVM: unregister notifiers in hyp mode teardown path
arm64: KVM: Warn when PARange is less than 40 bits
KVM: arm/arm64: Handle forward time correction gracefully
arm64: KVM: Add braces to multi-line if statement in virtual PMU code
Tony Luck [Wed, 6 Apr 2016 08:05:16 +0000 (10:05 +0200)]
x86/mce: Avoid using object after free in genpool
When we loop over all queued machine check error records to pass them
to the registered notifiers we use llist_for_each_entry(). But the loop
calls gen_pool_free() for the entry in the body of the loop - and then
the iterator looks at node->next after the free.
Use llist_for_each_entry_safe() instead.
Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Cc: Gong Chen <gong.chen@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/0205920@agluck-desk.sc.intel.com Link: http://lkml.kernel.org/r/1459929916-12852-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
ALSA: hda - Fix inconsistent monitor_present state until repoll
While the previous commit fixed the missing monitor_present flag
update, it may be still in an inconsistent state while the driver
repolls: the flag itself is updated, but the eld_valid flag and the
contents don't follow until the repoll finishes (and may be repeated
for a few times).
The basic problem is that pin_eld->monitor_present is updated in the
caller side. This should have been updated only in update_eld(). So,
the proper fix is to avoid accessing pin_eld but only spec->temp_eld.
ALSA: hda - Fix regression of monitor_present flag in eld proc file
The commit [bd48128539ab: ALSA: hda - Fix forgotten HDMI
monitor_present update] covered the missing update of monitor_present
flag, but this caused a regression for devices without the i915 eld
notifier. Since the old code supposed that pin_eld->monitor_present
was updated by the caller side, the hdmi_present_sense_via_verbs()
doesn't update the temporary eld->monitor_present but only
pin_eld->monitor_present, which is now overridden in update_eld().
The fix is to update pin_eld->monitor_present as well before calling
update_eld().
Note that this may still leave monitor_present flag in an inconsistent
state when the driver repolls, but this is at least the old behavior.
More proper fix will follow in the later patch.
Jaegeuk Kim [Tue, 12 Apr 2016 23:05:36 +0000 (16:05 -0700)]
ext4/fscrypto: avoid RCU lookup in d_revalidate
As Al pointed, d_revalidate should return RCU lookup before using d_inode.
This was originally introduced by:
commit 34286d666230 ("fs: rcu-walk aware d_revalidate method").
Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Theodore Ts'o <tytso@mit.edu> Cc: stable <stable@vger.kernel.org>
Seth Forshee [Wed, 9 Mar 2016 15:18:07 +0000 (09:18 -0600)]
debugfs: Make automount point inodes permanently empty
Starting with 4.1 the tracing subsystem has its own filesystem
which is automounted in the tracing subdirectory of debugfs.
Prior to this debugfs could be bind mounted in a cloned mount
namespace, but if tracefs has been mounted under debugfs this
now fails because there is a locked child mount. This creates
a regression for container software which bind mounts debugfs
to satisfy the assumption of some userspace software.
In other pseudo filesystems such as proc and sysfs we're already
creating mountpoints like this in such a way that no dirents can
be created in the directories, allowing them to be exceptions to
some MNT_LOCKED tests. In fact we're already do this for the
tracefs mountpoint in sysfs.
Do the same in debugfs_create_automount(), since the intention
here is clearly to create a mountpoint. This fixes the regression,
as locked child mounts on permanently empty directories do not
cause a bind mount to fail.
Nicolai Stange [Tue, 22 Mar 2016 13:11:20 +0000 (14:11 +0100)]
debugfs: unproxify files created through debugfs_create_u32_array()
The struct file_operations u32_array_fops associated with files created
through debugfs_create_u32_array() has been lifetime aware already:
everything needed for subsequent operation is copied to a ->f_private
buffer at file opening time in u32_array_open(). Now, ->open() is always
protected against file removal issues by the debugfs core.
There is no need for the debugfs core to wrap the u32_array_fops
with a file lifetime managing proxy.
Make debugfs_create_u32_array() create its files in non-proxying operation
mode by means of debugfs_create_file_unsafe().
Nicolai Stange [Tue, 22 Mar 2016 13:11:19 +0000 (14:11 +0100)]
debugfs: unproxify files created through debugfs_create_blob()
Currently, the struct file_operations fops_blob associated with files
created through the debugfs_create_blob() helpers are not file
lifetime aware.
Thus, a lifetime managing proxy is created around fops_blob each time such
a file is opened which is an unnecessary waste of resources.
Implement file lifetime management for the fops_bool file_operations.
Namely, make read_file_blob() safe gainst file removals by means of
debugfs_use_file_start() and debugfs_use_file_finish().
Make debugfs_create_blob() create its files in non-proxying operation mode
by means of debugfs_create_file_unsafe().
Nicolai Stange [Tue, 22 Mar 2016 13:11:18 +0000 (14:11 +0100)]
debugfs: unproxify files created through debugfs_create_bool()
Currently, the struct file_operations fops_bool associated with files
created through the debugfs_create_bool() helpers are not file
lifetime aware.
Thus, a lifetime managing proxy is created around fops_bool each time such
a file is opened which is an unnecessary waste of resources.
Implement file lifetime management for the fops_bool file_operations.
Namely, make debugfs_read_file_bool() and debugfs_write_file_bool() safe
against file removals by means of debugfs_use_file_start() and
debugfs_use_file_finish().
Make debugfs_create_bool() create its files in non-proxying operation mode
through debugfs_create_mode_unsafe().
Finally, purge debugfs_create_mode() as debugfs_create_bool() had been its
last user.
Nicolai Stange [Tue, 22 Mar 2016 13:11:17 +0000 (14:11 +0100)]
debugfs: unproxify integer attribute files
Currently, the struct file_operations associated with the integer attribute
style files created through the debugfs_create_*() helpers are not file
lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE().
Thus, a lifetime managing proxy is created around the original fops each
time such a file is opened which is an unnecessary waste of resources.
Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself
to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing
within the struct file_operations thus defined.
Introduce the debugfs_create_mode_unsafe() helper, analogous to
debugfs_create_mode(), but distinct in that it creates the files in
non-proxying operation mode through debugfs_create_file_unsafe().
Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE()
into debugfs_create_mode_unsafe() instead of former debugfs_create_mode().
Nicolai Stange [Tue, 22 Mar 2016 13:11:16 +0000 (14:11 +0100)]
debugfs, coccinelle: check for obsolete DEFINE_SIMPLE_ATTRIBUTE() usage
In order to protect against file removal races, debugfs files created via
debugfs_create_file() now get wrapped by a struct file_operations at their
opening.
If the original struct file_operations are known to be safe against removal
races by themselves already, the proxy creation may be bypassed by creating
the files through debugfs_create_file_unsafe().
In order to help debugfs users who use the common
DEFINE_SIMPLE_ATTRIBUTE() + debugfs_create_file()
idiom to transition to removal safe struct file_operations, the helper
macro DEFINE_DEBUGFS_ATTRIBUTE() has been introduced.
Thus, the preferred strategy is to use
DEFINE_DEBUGFS_ATTRIBUTE() + debugfs_create_file_unsafe()
now.
Introduce a Coccinelle script that searches for
DEFINE_SIMPLE_ATTRIBUTE()-defined struct file_operations handed into
debugfs_create_file(). Suggest to turn these usages into the
DEFINE_DEBUGFS_ATTRIBUTE() + debugfs_create_file_unsafe()
pattern.
Nicolai Stange [Tue, 22 Mar 2016 13:11:15 +0000 (14:11 +0100)]
debugfs: add support for self-protecting attribute file fops
In order to protect them against file removal issues, debugfs_create_file()
creates a lifetime managing proxy around each struct file_operations
handed in.
In cases where this struct file_operations is able to manage file lifetime
by itself already, the proxy created by debugfs is a waste of resources.
The most common class of struct file_operations given to debugfs are those
defined by means of the DEFINE_SIMPLE_ATTRIBUTE() macro.
Introduce a DEFINE_DEBUGFS_ATTRIBUTE() macro to allow any
struct file_operations of this class to be easily made file lifetime aware
and thus, to be operated unproxied.
Specifically, introduce debugfs_attr_read() and debugfs_attr_write()
which wrap simple_attr_read() and simple_attr_write() under the protection
of a debugfs_use_file_start()/debugfs_use_file_finish() pair.
Make DEFINE_DEBUGFS_ATTRIBUTE() set the defined struct file_operations'
->read() and ->write() members to these wrappers.
Export debugfs_create_file_unsafe() in order to allow debugfs users to
create their files in non-proxying operation mode.
Nicolai Stange [Tue, 22 Mar 2016 13:11:14 +0000 (14:11 +0100)]
debugfs: prevent access to removed files' private data
Upon return of debugfs_remove()/debugfs_remove_recursive(), it might
still be attempted to access associated private file data through
previously opened struct file objects. If that data has been freed by
the caller of debugfs_remove*() in the meanwhile, the reading/writing
process would either encounter a fault or, if the memory address in
question has been reassigned again, unrelated data structures could get
overwritten.
However, since debugfs files are seldomly removed, usually from module
exit handlers only, the impact is very low.
Currently, there are ~1000 call sites of debugfs_create_file() spread
throughout the whole tree and touching all of those struct file_operations
in order to make them file removal aware by means of checking the result of
debugfs_use_file_start() from within their methods is unfeasible.
Instead, wrap the struct file_operations by a lifetime managing proxy at
file open:
- In debugfs_create_file(), the original fops handed in has got stashed
away in ->d_fsdata already.
- In debugfs_create_file(), install a proxy file_operations factory,
debugfs_full_proxy_file_operations, at ->i_fop.
This proxy factory has got an ->open() method only. It carries out some
lifetime checks and if successful, dynamically allocates and sets up a new
struct file_operations proxy at ->f_op. Afterwards, it forwards to the
->open() of the original struct file_operations in ->d_fsdata, if any.
The dynamically set up proxy at ->f_op has got a lifetime managing wrapper
set for each of the methods defined in the original struct file_operations
in ->d_fsdata.
Its ->release()er frees the proxy again and forwards to the original
->release(), if any.
In order not to mislead the VFS layer, it is strictly necessary to leave
those fields blank in the proxy that have been NULL in the original
struct file_operations also, i.e. aren't supported. This is why there is a
need for dynamically allocated proxies. The choice made not to allocate a
proxy instance for every dentry at file creation, but for every
struct file object instantiated thereof is justified by the expected usage
pattern of debugfs, namely that in general very few files get opened more
than once at a time.
The wrapper methods set in the struct file_operations implement lifetime
managing by means of the SRCU protection facilities already in place for
debugfs:
They set up a SRCU read side critical section and check whether the dentry
is still alive by means of debugfs_use_file_start(). If so, they forward
the call to the original struct file_operation stored in ->d_fsdata, still
under the protection of the SRCU read side critical section.
This SRCU read side critical section prevents any pending debugfs_remove()
and friends to return to their callers. Since a file's private data must
only be freed after the return of debugfs_remove(), the ongoing proxied
call is guarded against any file removal race.
If, on the other hand, the initial call to debugfs_use_file_start() detects
that the dentry is dead, the wrapper simply returns -EIO and does not
forward the call. Note that the ->poll() wrapper is special in that its
signature does not allow for the return of arbitrary -EXXX values and thus,
POLLHUP is returned here.
In order not to pollute debugfs with wrapper definitions that aren't ever
needed, I chose not to define a wrapper for every struct file_operations
method possible. Instead, a wrapper is defined only for the subset of
methods which are actually set by any debugfs users.
Currently, these are:
The ->release() wrapper is special in that it does not protect the original
->release() in any way from dead files in order not to leak resources.
Thus, any ->release() handed to debugfs must implement file lifetime
management manually, if needed.
For only 33 out of a total of 434 releasers handed in to debugfs, it could
not be verified immediately whether they access data structures that might
have been freed upon a debugfs_remove() return in the meanwhile.
Export debugfs_use_file_start() and debugfs_use_file_finish() in order to
allow any ->release() to manually implement file lifetime management.
For a set of common cases of struct file_operations implemented by the
debugfs_core itself, future patches will incorporate file lifetime
management directly within those in order to allow for their unproxied
operation. Rename the original, non-proxying "debugfs_create_file()" to
"debugfs_create_file_unsafe()" and keep it for future internal use by
debugfs itself. Factor out code common to both into the new
__debugfs_create_file().
Nicolai Stange [Tue, 22 Mar 2016 13:11:13 +0000 (14:11 +0100)]
debugfs: prevent access to possibly dead file_operations at file open
Nothing prevents a dentry found by path lookup before a return of
__debugfs_remove() to actually get opened after that return. Now, after
the return of __debugfs_remove(), there are no guarantees whatsoever
regarding the memory the corresponding inode's file_operations object
had been kept in.
Since __debugfs_remove() is seldomly invoked, usually from module exit
handlers only, the race is hard to trigger and the impact is very low.
A discussion of the problem outlined above as well as a suggested
solution can be found in the (sub-)thread rooted at
http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk
("Yet another pipe related oops.")
Basically, Greg KH suggests to introduce an intermediate fops and
Al Viro points out that a pointer to the original ones may be stored in
->d_fsdata.
Follow this line of reasoning:
- Add SRCU as a reverse dependency of DEBUG_FS.
- Introduce a srcu_struct object for the debugfs subsystem.
- In debugfs_create_file(), store a pointer to the original
file_operations object in ->d_fsdata.
- Make debugfs_remove() and debugfs_remove_recursive() wait for a
SRCU grace period after the dentry has been delete()'d and before they
return to their callers.
- Introduce an intermediate file_operations object named
"debugfs_open_proxy_file_operations". It's ->open() functions checks,
under the protection of a SRCU read lock, whether the dentry is still
alive, i.e. has not been d_delete()'d and if so, tries to acquire a
reference on the owning module.
On success, it sets the file object's ->f_op to the original
file_operations and forwards the ongoing open() call to the original
->open().
- For clarity, rename the former debugfs_file_operations to
debugfs_noop_file_operations -- they are in no way canonical.
The choice of SRCU over "normal" RCU is justified by the fact, that the
former may also be used to protect ->i_private data from going away
during the execution of a file's readers and writers which may (and do)
sleep.
Finally, introduce the fs/debugfs/internal.h header containing some
declarations internal to the debugfs implementation.
Olof Johansson [Tue, 12 Apr 2016 19:35:07 +0000 (12:35 -0700)]
Merge tag 'mvebu-fixes-4.6-1' of git://git.infradead.org/linux-mvebu into fixes
mvebu fixes for 4.6 (part 1)
- fix USB adress register for Linksys Armada 388 based boards
- fix build warning in mvebu-mbus
* tag 'mvebu-fixes-4.6-1' of git://git.infradead.org/linux-mvebu:
ARM: mvebu: Correct unit address for linksys
bus: mvebu-mbus: use %pa to print phys_addr_t
Olof Johansson [Tue, 12 Apr 2016 19:32:35 +0000 (12:32 -0700)]
Merge tag 'omap-for-v4.6/fixes-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes
Fixes for omaps against v4.6-rc1. Mostly minor fixes for the newer
SoCs with few board fixes and a fix for a long time hwmod bug:
- Fix cpsw_emac0 link type for baltos-ir5221
- Fix interrupt type for TWD
- Fix edma memcpy channel allocation for am43x
- Fix am43x-epos sycntimer32k by using the correct assigned clock
- Fix interconnect barrier for dra7
- Fix a long time hwmod bug for updating sysconfig register properly
- Fix flakey booting on dm814x where USB reset needs a delay
And there is one minor change that is not strictly a fix, but is
good to have for proper hardware detection:
- Detect dra7 silicon revision 2.0 properly
* tag 'omap-for-v4.6/fixes-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: dts: am335x-baltos-ir5221: fix cpsw_emac0 link type
ARM: OMAP: Correct interrupt type for ARM TWD
ARM: DRA722: Add ID detect for Silicon Rev 2.0
ARM: dts: am43xx: fix edma memcpy channel allocation
ARM: dts: AM43x-epos: Fix clk parent for synctimer
ARM: OMAP2: Fix up interconnect barrier initialization for DRA7
ARM: OMAP2+: hwmod: Fix updating of sysconfig register
ARM: OMAP2+: Use srst_udelay for USB on dm814x
Jaegeuk Kim [Mon, 11 Apr 2016 22:51:57 +0000 (15:51 -0700)]
fscrypto: don't let data integrity writebacks fail with ENOMEM
This patch fixes the issue introduced by the ext4 crypto fix in a same manner.
For F2FS, however, we flush the pending IOs and wait for a while to acquire free
memory.
Fixes: c9af28fdd4492 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM") Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
drm/exynos: Use VIDEO_SAMSUNG_S5P_G2D=n as G2D Kconfig dependency
Commit 254d4d111ee1 ("drm/exynos: Add dependency for G2D in Kconfig") made
the DRM_EXYNOS_G2D symbol to only be selectable if the s5p-g2d V4L2 driver
is not enabled, since both use the same HW IP block.
But added the dependency as depends on !VIDEO_SAMSUNG_S5P_G2D which isn't
correct since Kconfig expressions are not boolean but tristate. So it will
only evaluate to 'n' if VIDEO_SAMSUNG_S5P_G2D=y but it will evaluate to m
if VIDEO_SAMSUNG_S5P_G2D=m.
This means that both the V4L2 and DRM drivers can be enabled if the former
is enabled as a module, which is not what we want.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Inki Dae <inki.dae@samsung.com>
Marek Szyprowski [Thu, 17 Mar 2016 06:53:12 +0000 (07:53 +0100)]
drm/exynos: fimd: fix broken dp_clock control
Commit 1feafd3afd294b03dbbedb8e8f94e0c4db526f10 ("drm/exynos: add
exynos5420 support for fimd") add support for Exynos 5420 SoC, but it
broke enabling display clock feature because of incorrect condition
check. This patch fixes it, so display is working again on platforms
requiring display clock control (i.e. Exynos5250-based SNOW platform).
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Inki Dae <inki.dae@samsung.com>
Andrzej Hajda [Tue, 15 Mar 2016 11:43:21 +0000 (12:43 +0100)]
drm/exynos: build fbdev code conditionally
Fbdev code should be compiled only if CONFIG_DRM_FBDEV_EMULATION option
is enabled. The patch fixes exynos-drm code trying to manipulate
fbdev data which is not initialized in case CONFIG_DRM_FBDEV_EMULATION
is disabled.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Signed-off-by: Inki Dae <inki.dae@samsung.com>
Andrzej Hajda [Tue, 15 Mar 2016 11:38:02 +0000 (12:38 +0100)]
drm/exynos: fix adjusted_mode pointer in exynos_plane_mode_set
exynos_plane_mode_set should use adjusted_mode from the same atomic state as
plane state. Otherwise it will result in incorrect behavior in case
crtc mode changes.
The patch fixes bug with black console framebuffer in case of command mode
panels.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Signed-off-by: Inki Dae <inki.dae@samsung.com>
projects / linux-beck.git / log