Removing explicit calls to mmiowb() from driver code means that we must
now call into the generic mmiowb_spin_{lock,unlock}() functions from the
core spinlock code. In order to elide barriers following critical
sections without any I/O writes, we also hook into the asm-generic I/O
routines.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In preparation for removing all explicit mmiowb() calls from driver
code, implement a tracking system in asm-generic based loosely on the
PowerPC implementation. This allows architectures with a non-empty
mmiowb() definition to have the barrier automatically inserted in
spin_unlock() following a critical section containing an I/O write.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
While the cpuinfo.max_freq value doesn't really matter for
intel_pstate in the active mode, in the passive mode it is used by
governors as the maximum physical frequency of the CPU and the
results of governor computations generally depend on it. Also it
is made available to user space via sysfs and it should match the
current HW configuration.
For this reason, make intel_pstate update cpuinfo.max_freq for all
CPUs if it detects a global change of turbo frequency settings from
"disable" to "enable" or the other way associated with a _PPC change
notification from the platform firmware.
Note that policy_is_inactive(), cpufreq_cpu_acquire(),
cpufreq_cpu_release(), and cpufreq_set_policy() need to be made
available to it for this purpose.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759
Reported-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
The direction inversion semantics are now handled by simply
using the registers for in/out available, no need to keep
track of inversion semantics exmplicitly anymore.
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Jan Kotas <jank@cadence.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The symbol that is being used in the #if/#endif block is not the one
which is mentioned at the bottom.
Fixes: 93af53b863 ("nand: omap2: Remove horrible ifdefs to fix module probe")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
nand_device embeds a nand_ecc_req object which contains the minimum
strength and step-size required by the NAND device.
Drop the chip->ecc_{strength,step}_ds fields and use
chip->base.eccreq.{strength,step_size} instead.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
The target size can now be returned by nanddev_get_targetsize(). Get
rid of the chip->chipsize field and use this helper instead.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Now that we inherit from nand_device, we can use
nand_device->memorg.bits_per_cell instead of having our own field at
the nand_chip level.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
nanddev_mtd_max_bad_blocks() is implemented by the generic NAND layer
and is already doing what we need. Reuse this function instead of
having our own implementation.
While at it, get rid of the ->max_bb_per_die and ->blocks_per_die
fields which are now unused.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Looking at the field names it's hard to tell what ->data_buf, ->pagebuf
and ->pagebuf_bitflips are for. Clarify that by moving those fields
in a sub-struct named pagecache.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
We plan to move cache related fields to a pagecache struct in nand_chip
but some drivers access ->pagebuf directly to invalidate the cache
before they start using ->data_buf.
Let's provide an helper that returns a pointer to ->data_buf after
invalidating the cache.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
The generic NAND layer provides abstraction of NAND devices no matter
the bus that is used to communicate with the chip. Basing the raw NAND
core on this generic layer should avoid duplication of common
operations, like iterating over all pages/blocks for MTD IO/erase
operations.
In order to re-use this layer, we must first inherit from nand_device
and then initialize the nand_device struct appropriately. This patch
is taking care of the former.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Some drivers in the raw NAND framework seems to need this helper, so
let's just add it instead of open-coding the logic.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
NAND datasheets usually give the maximum number of bad blocks per LUN
and this number can be used to help upper layers decide how much blocks
they should reserve for bad block handling.
Add a max_bad_eraseblocks_per_lun to the nand_memory_organization
struct and update the NAND_MEMORG() macro (and its users) accordingly.
We also provide a default mtd->_max_bad_blocks() implementation.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Recently, for Intel platforms the "ignore_module_refcount" field
was introduced for the component driver. In order to avoid a
deadlock preventing the PCI modules from being removed
even when the card was idle, the refcounts were not incremented
for the device driver module during component probe.
However, this change introduced a nasty side effect:
the device driver module can be unloaded while a pcm stream is open.
This patch proposes to change the field to be renamed as
"module_get_upon_open". When this field is set, the module
refcount should be incremented on pcm open amd decremented
upon pcm close. This will enable modules to be removed
when no PCM playback/capture happens and prevent removal
when the component is actually in use.
Also, align with the skylake component driver with the new name.
Fixes: b450b878('ASoC: core: don't increase component module refcount
unconditionally'
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This structure is now only 4 bytes, so its more efficient
to cache a copy rather than its address.
No significant size difference in allmodconfig vmlinux.
With non-modular kernel that has all XFRM options enabled, this
series reduces vmlinux image size by ~11kb. All xfrm_mode
indirections are gone and all modes are built-in.
before (ipsec-next master):
text data bss dec filename
21071494 7233140 11104324 39408958 vmlinux.master
after this series:
21066448 7226772 11104324 39397544 vmlinux.patched
With allmodconfig kernel, the size increase is only 362 bytes,
even all the xfrm config options removed in this series are
modular.
before:
text data bss dec filename
15731286 6936912 4046908 26715106 vmlinux.master
after this series:
15731492 6937068 4046908 26715468 vmlinux
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
after previous changes, xfrm_mode contains no function pointers anymore
and all modules defining such struct contain no code except an init/exit
functions to register the xfrm_mode struct with the xfrm core.
Just place the xfrm modes core and remove the modules,
the run-time xfrm_mode register/unregister functionality is removed.
Before:
text data bss dec filename
7523 200 2364 10087 net/xfrm/xfrm_input.o
40003 628 440 41071 net/xfrm/xfrm_state.o
15730338 6937080 4046908 26714326 vmlinux
7389 200 2364 9953 net/xfrm/xfrm_input.o
40574 656 440 41670 net/xfrm/xfrm_state.o
15730084 6937068 4046908 26714060 vmlinux
The xfrm*_mode_{transport,tunnel,beet} modules are gone.
v2: replace CONFIG_INET6_XFRM_MODE_* IS_ENABLED guards with CONFIG_IPV6
ones rather than removing them.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Adds an EXPORT_SYMBOL for afinfo_get_rcu, as it will now be called from
ipv6 in case of CONFIG_IPV6=m.
This change has virtually no effect on vmlinux size, but it reduces
afinfo size and allows followup patch to make xfrm modes const.
v2: mark if (afinfo) tests as likely (Sabrina)
re-fetch afinfo according to inner_mode in xfrm_prepare_input().
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
similar to previous patch: no external module dependencies,
so we can avoid the indirection by placing this in the core.
This change removes the last indirection from xfrm_mode and the
xfrm4|6_mode_{beet,tunnel}.c modules contain (almost) no code anymore.
Before:
text data bss dec hex filename
3957 136 0 4093 ffd net/xfrm/xfrm_output.o
587 44 0 631 277 net/ipv4/xfrm4_mode_beet.o
649 32 0 681 2a9 net/ipv4/xfrm4_mode_tunnel.o
625 44 0 669 29d net/ipv6/xfrm6_mode_beet.o
599 32 0 631 277 net/ipv6/xfrm6_mode_tunnel.o
After:
text data bss dec hex filename
5359 184 0 5543 15a7 net/xfrm/xfrm_output.o
171 24 0 195 c3 net/ipv4/xfrm4_mode_beet.o
171 24 0 195 c3 net/ipv4/xfrm4_mode_tunnel.o
172 24 0 196 c4 net/ipv6/xfrm6_mode_beet.o
172 24 0 196 c4 net/ipv6/xfrm6_mode_tunnel.o
v2: fold the *encap_add functions into xfrm*_prepare_output
preserve (move) output2 comment (Sabrina)
use x->outer_mode->encap, not inner
fix a build breakage on ppc (kbuild robot)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
No external dependencies on any module, place this in the core.
Increase is about 1800 byte for xfrm_input.o.
The beet helpers get added to internal header, as they can be reused
from xfrm_output.c in the next patch (kernel contains several
copies of them in the xfrm{4,6}_mode_beet.c files).
Before:
text data bss dec filename
5578 176 2364 8118 net/xfrm/xfrm_input.o
1180 64 0 1244 net/ipv4/xfrm4_mode_beet.o
171 40 0 211 net/ipv4/xfrm4_mode_transport.o
1163 40 0 1203 net/ipv4/xfrm4_mode_tunnel.o
1083 52 0 1135 net/ipv6/xfrm6_mode_beet.o
172 40 0 212 net/ipv6/xfrm6_mode_ro.o
172 40 0 212 net/ipv6/xfrm6_mode_transport.o
1056 40 0 1096 net/ipv6/xfrm6_mode_tunnel.o
After:
text data bss dec filename
7373 200 2364 9937 net/xfrm/xfrm_input.o
587 44 0 631 net/ipv4/xfrm4_mode_beet.o
171 32 0 203 net/ipv4/xfrm4_mode_transport.o
649 32 0 681 net/ipv4/xfrm4_mode_tunnel.o
625 44 0 669 net/ipv6/xfrm6_mode_beet.o
172 32 0 204 net/ipv6/xfrm6_mode_ro.o
172 32 0 204 net/ipv6/xfrm6_mode_transport.o
599 32 0 631 net/ipv6/xfrm6_mode_tunnel.o
v2: pass inner_mode to xfrm_inner_mode_encap_remove to fix
AF_UNSPEC selector breakage (bisected by Benedict Wong)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
There are only two versions (tunnel and transport). The ip/ipv6 versions
are only differ in sizeof(iphdr) vs ipv6hdr.
Place this in the core and use x->outer_mode->encap type to call the
correct adjustment helper.
Before:
text data bss dec filename
15730311 6937008 4046908 26714227 vmlinux
After:
15730428 6937008 4046908 26714344 vmlinux
(about 117 byte increase)
v2: use family from x->outer_mode, not inner
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Same is input indirection. Only exception: we need to export
xfrm_outer_mode_output for pktgen.
Increases size of vmlinux by about 163 byte:
Before:
text data bss dec filename
15730208 6936948 4046908 26714064 vmlinux
After:
15730311 6937008 4046908 26714227 vmlinux
xfrm_inner_extract_output has no more external callers, make it static.
v2: add IS_ENABLED(IPV6) guard in xfrm6_prepare_output
add two missing breaks in xfrm_outer_mode_output (Sabrina Dubroca)
add WARN_ON_ONCE for 'call AF_INET6 related output function, but
CONFIG_IPV6=n' case.
make xfrm_inner_extract_output static
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
No need for any indirection or abstraction here, both functions
are pretty much the same and quite small, they also have no external
dependencies.
xfrm_prepare_input can then be made static.
With allmodconfig build, size increase of vmlinux is 25 byte:
Before:
text data bss dec filename
15730207 6936924 4046908 26714039 vmlinux
After:
15730208 6936948 4046908 26714064 vmlinux
v2: Fix INET_XFRM_MODE_TRANSPORT name in is-enabled test (Sabrina Dubroca)
change copied comment to refer to transport and network header,
not skb->{h,nh}, which don't exist anymore. (Sabrina)
make xfrm_prepare_input static (Eyal Birger)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This patch creates set_cs_timing SPI master optional method for
SPI masters to implement configuring CS timing if applicable.
This patch also creates spi_cs_timing accessory for SPI clients to
use for requesting SPI master controllers to configure device requested
CS setup time, hold time and inactive delay.
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This will be useful to know if we're supposed to decode ipv4 or ipv6.
While at it, make the unregister function return void, all module_exit
functions did just BUG(); there is never a point in doing error checks
if there is no way to handle such error.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
The current definition and implementation of the SEV_GET_ID command
does not provide the length of the unique ID returned by the firmware.
As per the firmware specification, the firmware may return an ID
length that is not restricted to 64 bytes as assumed by the SEV_GET_ID
command.
Introduce the SEV_GET_ID2 command to overcome with the SEV_GET_ID
limitations. Deprecate the SEV_GET_ID in the favor of SEV_GET_ID2.
At the same time update SEV API web link.
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Nathaniel McCallum <npmccallum@redhat.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Native bit_spin_locks are not tracked by lockdep.
The bit_spin_locks used for rhashtable buckets are local
to the rhashtable implementation, so there is little opportunity
for the sort of misuse that lockdep might detect.
However locks are held while a hash function or compare
function is called, and if one of these took a lock,
a misbehaviour is possible.
As it is quite easy to add lockdep support this unlikely
possibility seems to be enough justification.
So create a lockdep class for bucket bit_spin_lock and attach
through a lockdep_map in each bucket_table.
Without the 'nested' annotation in rhashtable_rehash_one(), lockdep
correctly reports a possible problem as this lock is taken
while another bucket lock (in another table) is held. This
confirms that the added support works.
With the correct nested annotation in place, lockdep reports
no problems.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch changes rhashtables to use a bit_spin_lock on BIT(1) of the
bucket pointer to lock the hash chain for that bucket.
The benefits of a bit spin_lock are:
- no need to allocate a separate array of locks.
- no need to have a configuration option to guide the
choice of the size of this array
- locking cost is often a single test-and-set in a cache line
that will have to be loaded anyway. When inserting at, or removing
from, the head of the chain, the unlock is free - writing the new
address in the bucket head implicitly clears the lock bit.
For __rhashtable_insert_fast() we ensure this always happens
when adding a new key.
- even when lockings costs 2 updates (lock and unlock), they are
in a cacheline that needs to be read anyway.
The cost of using a bit spin_lock is a little bit of code complexity,
which I think is quite manageable.
Bit spin_locks are sometimes inappropriate because they are not fair -
if multiple CPUs repeatedly contend of the same lock, one CPU can
easily be starved. This is not a credible situation with rhashtable.
Multiple CPUs may want to repeatedly add or remove objects, but they
will typically do so at different buckets, so they will attempt to
acquire different locks.
As we have more bit-locks than we previously had spinlocks (by at
least a factor of two) we can expect slightly less contention to
go with the slightly better cache behavior and reduced memory
consumption.
To enhance type checking, a new struct is introduced to represent the
pointer plus lock-bit
that is stored in the bucket-table. This is "struct rhash_lock_head"
and is empty. A pointer to this needs to be cast to either an
unsigned lock, or a "struct rhash_head *" to be useful.
Variables of this type are most often called "bkt".
Previously "pprev" would sometimes point to a bucket, and sometimes a
->next pointer in an rhash_head. As these are now different types,
pprev is NULL when it would have pointed to the bucket. In that case,
'blk' is used, together with correct locking protocol.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rather than returning a pointer to a static nulls, rht_bucket_var()
now returns NULL if the bucket doesn't exist.
This will make the next patch, which stores a bitlock in the
bucket pointer, somewhat cleaner.
This change involves introducing __rht_bucket_nested() which is
like rht_bucket_nested(), but doesn't provide the static nulls,
and changing rht_bucket_nested() to call this and possible
provide a static nulls - as is still needed for the non-var case.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull ARM SoC fixes from Olof Johansson:
"A collection of fixes from the last few weeks. Most of them are
smaller tweaks and fixes to DT and hardware descriptions for boards.
Some of the more significant ones are:
- eMMC and RGMII stability tweaks for rk3288
- DDC fixes for Rock PI 4
- Audio fixes for two TI am335x eval boards
- D_CAN clock fix for am335x
- Compilation fixes for clang
- !HOTPLUG_CPU compilation fix for one of the new platforms this
release (milbeaut)
- A revert of a gpio fix for nomadik that instead was fixed in the
gpio subsystem
- Whitespace fix for the DT JSON schema (no tabs allowed)"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (25 commits)
ARM: milbeaut: fix build with !CONFIG_HOTPLUG_CPU
ARM: iop: don't use using 64-bit DMA masks
ARM: orion: don't use using 64-bit DMA masks
Revert "ARM: dts: nomadik: Fix polarity of SPI CS"
dt-bindings: cpu: Fix JSON schema
arm/mach-at91/pm : fix possible object reference leak
ARM: dts: at91: Fix typo in ISC_D0 on PC9
ARM: dts: Fix dcan clkctrl clock for am3
reset: meson-audio-arb: Fix missing .owner setting of reset_controller_dev
dt-bindings: reset: meson-g12a: Add missing USB2 PHY resets
ARM: dts: rockchip: Remove #address/#size-cells from rk3288-veyron gpio-keys
ARM: dts: rockchip: Remove #address/#size-cells from rk3288 mipi_dsi
ARM: dts: rockchip: Fix gpu opp node names for rk3288
ARM: dts: am335x-evmsk: Correct the regulators for the audio codec
ARM: dts: am335x-evm: Correct the regulators for the audio codec
ARM: OMAP2+: add missing of_node_put after of_device_is_available
ARM: OMAP1: ams-delta: Fix broken GPIO ID allocation
arm64: dts: stratix10: add the sysmgr-syscon property from the gmac's
arm64: dts: rockchip: fix rk3328 sdmmc0 write errors
arm64: dts: rockchip: fix rk3328 rgmii high tx error rate
...
Reset controller fixes for v5.1
This tag adds missing USB PHY reset lines to the Meson G12A reset
controller header and fixes the Meson Audio ARB driver to prevent
module unloading while it is in use.
* tag 'reset-fixes-for-v5.1' of git://git.pengutronix.de/pza/linux:
reset: meson-audio-arb: Fix missing .owner setting of reset_controller_dev
dt-bindings: reset: meson-g12a: Add missing USB2 PHY resets
Signed-off-by: Olof Johansson <olof@lixom.net>
The current handling of MSR_IA32_ENERGY_PERF_BIAS in the kernel is
problematic, because it may cause changes made by user space to that
MSR (with the help of the x86_energy_perf_policy tool, for example)
to be lost every time a CPU goes offline and then back online as well
as during system-wide power management transitions into sleep states
and back into the working state.
The first problem is that if the current EPB value for a CPU going
online is 0 ('performance'), the kernel will change it to 6 ('normal')
regardless of whether or not this is the first bring-up of that CPU.
That also happens during system-wide resume from sleep states
(including, but not limited to, hibernation). However, the EPB may
have been adjusted by user space this way and the kernel should not
blindly override that setting.
The second problem is that if the platform firmware resets the EPB
values for any CPUs during system-wide resume from a sleep state,
the kernel will not restore their previous EPB values that may
have been set by user space before the preceding system-wide
suspend transition. Again, that behavior may at least be confusing
from the user space perspective.
In order to address these issues, rework the handling of
MSR_IA32_ENERGY_PERF_BIAS so that the EPB value is saved on CPU
offline and restored on CPU online as well as (for the boot CPU)
during the syscore stages of system-wide suspend and resume
transitions, respectively.
However, retain the policy by which the EPB is set to 6 ('normal')
on the first bring-up of each CPU if its initial value is 0, based
on the observation that 0 may mean 'not initialized' just as well as
'performance' in that case.
While at it, move the MSR_IA32_ENERGY_PERF_BIAS handling code into
a separate file and document it in Documentation/admin-guide.
Fixes: abe48b1082 (x86, intel, power: Initialize MSR_IA32_ENERGY_PERF_BIAS)
Fixes: b51ef52df7 (x86/cpu: Restore MSR_IA32_ENERGY_PERF_BIAS after resume)
Reported-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Remove the LM3532 backlight driver references from the ti-lmu
code as dedicated driver support is available.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
This is similar to commit e285d5bfb7 ("NFC: Fix the number of pipes")
where we changed NFC_HCI_MAX_PIPES from 127 to 128.
As the comment next to the define explains, the pipe identifier is 7
bits long. The highest possible pipe is 127, but the number of possible
pipes is 128. As the code is now, then there is potential for an
out of bounds array access:
net/nfc/nci/hci.c:297 nci_hci_cmd_received() warn: array off by one?
'ndev->hci_dev->pipes[pipe]' '0-127 == 127'
Fixes: 11f54f2286 ("NFC: nci: Add HCI over NCI protocol support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 9c225f2655 ("vfs: atomic f_pos accesses as per POSIX") added
locking for file.f_pos access and in particular made concurrent read and
write not possible - now both those functions take f_pos lock for the
whole run, and so if e.g. a read is blocked waiting for data, write will
deadlock waiting for that read to complete.
This caused regression for stream-like files where previously read and
write could run simultaneously, but after that patch could not do so
anymore. See e.g. commit 581d21a2d0 ("xenbus: fix deadlock on writes
to /proc/xen/xenbus") which fixes such regression for particular case of
/proc/xen/xenbus.
The patch that added f_pos lock in 2014 did so to guarantee POSIX thread
safety for read/write/lseek and added the locking to file descriptors of
all regular files. In 2014 that thread-safety problem was not new as it
was already discussed earlier in 2006.
However even though 2006'th version of Linus's patch was adding f_pos
locking "only for files that are marked seekable with FMODE_LSEEK (thus
avoiding the stream-like objects like pipes and sockets)", the 2014
version - the one that actually made it into the tree as 9c225f2655 -
is doing so irregardless of whether a file is seekable or not.
See
https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/https://lwn.net/Articles/180387https://lwn.net/Articles/180396
for historic context.
The reason that it did so is, probably, that there are many files that
are marked non-seekable, but e.g. their read implementation actually
depends on knowing current position to correctly handle the read. Some
examples:
kernel/power/user.c snapshot_read
fs/debugfs/file.c u32_array_read
fs/fuse/control.c fuse_conn_waiting_read + ...
drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read
arch/s390/hypfs/inode.c hypfs_read_iter
...
Despite that, many nonseekable_open users implement read and write with
pure stream semantics - they don't depend on passed ppos at all. And for
those cases where read could wait for something inside, it creates a
situation similar to xenbus - the write could be never made to go until
read is done, and read is waiting for some, potentially external, event,
for potentially unbounded time -> deadlock.
Besides xenbus, there are 14 such places in the kernel that I've found
with semantic patch (see below):
drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write()
drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write()
drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write()
drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write()
net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write()
drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write()
drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write()
drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write()
net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write()
drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write()
drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write()
drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write()
drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write()
drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write()
In addition to the cases above another regression caused by f_pos
locking is that now FUSE filesystems that implement open with
FOPEN_NONSEEKABLE flag, can no longer implement bidirectional
stream-like files - for the same reason as above e.g. read can deadlock
write locking on file.f_pos in the kernel.
FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f7 ("fuse:
implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp
in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and
write routines not depending on current position at all, and with both
read and write being potentially blocking operations:
See
https://github.com/libfuse/osspdhttps://lwn.net/Articles/308445https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510
Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as
"somewhat pipe-like files ..." with read handler not using offset.
However that test implements only read without write and cannot exercise
the deadlock scenario:
https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216
I've actually hit the read vs write deadlock for real while implementing
my FUSE filesystem where there is /head/watch file, for which open
creates separate bidirectional socket-like stream in between filesystem
and its user with both read and write being later performed
simultaneously. And there it is semantically not easy to split the
stream into two separate read-only and write-only channels:
https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169
Let's fix this regression. The plan is:
1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS -
doing so would break many in-kernel nonseekable_open users which
actually use ppos in read/write handlers.
2. Add stream_open() to kernel to open stream-like non-seekable file
descriptors. Read and write on such file descriptors would never use
nor change ppos. And with that property on stream-like files read and
write will be running without taking f_pos lock - i.e. read and write
could be running simultaneously.
3. With semantic patch search and convert to stream_open all in-kernel
nonseekable_open users for which read and write actually do not
depend on ppos and where there is no other methods in file_operations
which assume @offset access.
4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via
steam_open if that bit is present in filesystem open reply.
It was tempting to change fs/fuse/ open handler to use stream_open
instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but
grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and
write handlers
https://codesearch.debian.net/search?q=-%3Enonseekable+%3Dhttps://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481
so if we would do such a change it will break a real user.
5. Add stream_open and FOPEN_STREAM handling to stable kernels starting
from v3.14+ (the kernel where 9c225f2655 first appeared).
This will allow to patch OSSPD and other FUSE filesystems that
provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE
in their open handler and this way avoid the deadlock on all kernel
versions. This should work because fs/fuse/ ignores unknown open
flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel
that is not aware of FOPEN_STREAM will be < v3.14 where just
FOPEN_NONSEEKABLE is sufficient to implement streams without read vs
write deadlock.
This patch adds stream_open, converts /proc/xen/xenbus to it and adds
semantic patch to automatically locate in-kernel places that are either
required to be converted due to read vs write deadlock, or that are just
safe to be converted because read and write do not use ppos and there
are no other funky methods in file_operations.
Regarding semantic patch I've verified each generated change manually -
that it is correct to convert - and each other nonseekable_open instance
left - that it is either not correct to convert there, or that it is not
converted due to current stream_open.cocci limitations.
The script also does not convert files that should be valid to convert,
but that currently have .llseek = noop_llseek or generic_file_llseek for
unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures. These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time. Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.
Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
